diff --git a/analysis_options.yaml b/analysis_options.yaml
index c5d8facf6bc..5c20c572edb 100644
--- a/analysis_options.yaml
+++ b/analysis_options.yaml
@@ -141,7 +141,7 @@ linter:
     - prefer_equal_for_default_values
     # - prefer_expression_function_bodies # conflicts with https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo#consider-using--for-short-functions-and-methods
     - prefer_final_fields
-    # - prefer_final_in_for_each # not yet tested
+    - prefer_final_in_for_each
     - prefer_final_locals
     # - prefer_for_elements_to_map_fromIterable # not yet tested
     - prefer_foreach
diff --git a/dev/benchmarks/macrobenchmarks/lib/src/cubic_bezier.dart b/dev/benchmarks/macrobenchmarks/lib/src/cubic_bezier.dart
index 766c69794d4..90ca20afd6d 100644
--- a/dev/benchmarks/macrobenchmarks/lib/src/cubic_bezier.dart
+++ b/dev/benchmarks/macrobenchmarks/lib/src/cubic_bezier.dart
@@ -146,7 +146,7 @@ class AnimatedBezierState extends State<AnimatedBezier>
 
     path.moveTo(100.0, 97.0);
 
-    for (Point p in pointList[0]) {
+    for (final Point p in pointList[0]) {
       path.lineTo(p.x, p.y);
     }
 
@@ -167,7 +167,7 @@ class AnimatedBezierState extends State<AnimatedBezier>
 
     bezier2Path.moveTo(0.0, 70.55);
 
-    for (Point p in pointList[1]) {
+    for (final Point p in pointList[1]) {
       bezier2Path.lineTo(p.x, p.y);
     }
 
@@ -188,7 +188,7 @@ class AnimatedBezierState extends State<AnimatedBezier>
 
     bezier3Path.moveTo(0.0, 69.48);
 
-    for (Point p in pointList[2]) {
+    for (final Point p in pointList[2]) {
       bezier3Path.lineTo(p.x, p.y);
     }
 
@@ -210,7 +210,7 @@ class AnimatedBezierState extends State<AnimatedBezier>
 
     bezier4Path.moveTo(0.0, 69.48);
 
-    for (Point p in pointList[3]) {
+    for (final Point p in pointList[3]) {
       bezier4Path.lineTo(p.x, p.y);
     }
 
@@ -221,7 +221,7 @@ class AnimatedBezierState extends State<AnimatedBezier>
   }
 
   List<PathDetail> _playReversed() {
-    for (List<Point> list in pointList) {
+    for (final List<Point> list in pointList) {
       if (list.isNotEmpty) {
         list.removeLast();
       }
@@ -232,7 +232,7 @@ class AnimatedBezierState extends State<AnimatedBezier>
 
     path.moveTo(100.0, 97.0);
 
-    for (Point point in points) {
+    for (final Point point in points) {
       path.lineTo(point.x, point.y);
     }
 
@@ -240,14 +240,14 @@ class AnimatedBezierState extends State<AnimatedBezier>
 
     bezier2Path.moveTo(0.0, 70.55);
 
-    for (Point p in pointList[1]) {
+    for (final Point p in pointList[1]) {
       bezier2Path.lineTo(p.x, p.y);
     }
 
     final Path bezier3Path = Path();
     bezier3Path.moveTo(0.0, 69.48);
 
-    for (Point p in pointList[2]) {
+    for (final Point p in pointList[2]) {
       bezier3Path.lineTo(p.x, p.y);
     }
 
@@ -255,7 +255,7 @@ class AnimatedBezierState extends State<AnimatedBezier>
 
     bezier4Path.moveTo(0.0, 69.48);
 
-    for (Point p in pointList[3]) {
+    for (final Point p in pointList[3]) {
       bezier4Path.lineTo(p.x, p.y);
     }
 
@@ -287,7 +287,7 @@ class AnimatedBezierState extends State<AnimatedBezier>
   void playAnimation() {
     isPlaying = true;
     isReversed = false;
-    for (List<Point> list in pointList) {
+    for (final List<Point> list in pointList) {
       list.clear();
     }
     controller.reset();
@@ -297,7 +297,7 @@ class AnimatedBezierState extends State<AnimatedBezier>
   void stopAnimation() {
     isPlaying = false;
     controller.stop();
-    for (List<Point> list in pointList) {
+    for (final List<Point> list in pointList) {
       list.clear();
     }
   }
diff --git a/dev/benchmarks/microbenchmarks/lib/common.dart b/dev/benchmarks/microbenchmarks/lib/common.dart
index 0fa0e8adc3a..62a08fd4675 100644
--- a/dev/benchmarks/microbenchmarks/lib/common.dart
+++ b/dev/benchmarks/microbenchmarks/lib/common.dart
@@ -51,7 +51,7 @@ class BenchmarkResultPrinter {
 
   String _printJson() {
     final Map<String, double> results = <String, double>{};
-    for (_BenchmarkResult result in _results) {
+    for (final _BenchmarkResult result in _results) {
       results[result.name] = result.value;
     }
     return json.encode(results);
@@ -59,7 +59,7 @@ class BenchmarkResultPrinter {
 
   String _printPlainText() {
     final StringBuffer buf = StringBuffer();
-    for (_BenchmarkResult result in _results) {
+    for (final _BenchmarkResult result in _results) {
       buf.writeln('${result.description}: ${result.value.toStringAsFixed(1)} ${result.unit}');
     }
     return buf.toString();
diff --git a/dev/benchmarks/microbenchmarks/lib/gestures/velocity_tracker_bench.dart b/dev/benchmarks/microbenchmarks/lib/gestures/velocity_tracker_bench.dart
index 93a4c2f6ef6..cfd1546fb10 100644
--- a/dev/benchmarks/microbenchmarks/lib/gestures/velocity_tracker_bench.dart
+++ b/dev/benchmarks/microbenchmarks/lib/gestures/velocity_tracker_bench.dart
@@ -16,7 +16,7 @@ void main() {
   print('Velocity tracker benchmark...');
   watch.start();
   for (int i = 0; i < _kNumIters; i += 1) {
-    for (PointerEvent event in velocityEventData) {
+    for (final PointerEvent event in velocityEventData) {
       if (event is PointerDownEvent || event is PointerMoveEvent)
         tracker.addPosition(event.timeStamp, event.position);
       if (event is PointerUpEvent)
diff --git a/dev/benchmarks/microbenchmarks/lib/language/sync_star_bench.dart b/dev/benchmarks/microbenchmarks/lib/language/sync_star_bench.dart
index b7572215014..dba12ac1b71 100644
--- a/dev/benchmarks/microbenchmarks/lib/language/sync_star_bench.dart
+++ b/dev/benchmarks/microbenchmarks/lib/language/sync_star_bench.dart
@@ -84,7 +84,7 @@ Iterable<int> generateIterableList() {
 
 int sumIterable(Iterable<int> values) {
   int result = 0;
-  for (int value in values) {
+  for (final int value in values) {
     result += value;
   }
   return result;
diff --git a/dev/benchmarks/microbenchmarks/lib/language/sync_star_semantics_bench.dart b/dev/benchmarks/microbenchmarks/lib/language/sync_star_semantics_bench.dart
index c5ffc2f7f61..0672841bfde 100644
--- a/dev/benchmarks/microbenchmarks/lib/language/sync_star_semantics_bench.dart
+++ b/dev/benchmarks/microbenchmarks/lib/language/sync_star_semantics_bench.dart
@@ -71,7 +71,7 @@ void main() {
 
 String consumeSpan(Iterable<InlineSpanSemanticsInformation> items) {
   String result = '';
-  for (InlineSpanSemanticsInformation span in items) {
+  for (final InlineSpanSemanticsInformation span in items) {
     result += span.text;
   }
   return result;
@@ -81,7 +81,7 @@ String consumeSpan(Iterable<InlineSpanSemanticsInformation> items) {
 Iterable<InlineSpanSemanticsInformation> combineSemanticsInfoSyncStar(List<InlineSpanSemanticsInformation> inputs) sync* {
   String workingText = '';
   String workingLabel;
-  for (InlineSpanSemanticsInformation info in inputs) {
+  for (final InlineSpanSemanticsInformation info in inputs) {
     if (info.requiresOwnNode) {
       if (workingText != null) {
         yield InlineSpanSemanticsInformation(workingText, semanticsLabel: workingLabel ?? workingText);
@@ -110,7 +110,7 @@ Iterable<InlineSpanSemanticsInformation> combineSemanticsInfoList(List<InlineSpa
   String workingText = '';
   String workingLabel;
   final List<InlineSpanSemanticsInformation> result = <InlineSpanSemanticsInformation>[];
-  for (InlineSpanSemanticsInformation info in inputs) {
+  for (final InlineSpanSemanticsInformation info in inputs) {
     if (info.requiresOwnNode) {
       if (workingText != null) {
         result.add(InlineSpanSemanticsInformation(workingText, semanticsLabel: workingLabel ?? workingText));
diff --git a/dev/bots/analyze-sample-code.dart b/dev/bots/analyze-sample-code.dart
index f4422340f7d..2957f26ccf1 100644
--- a/dev/bots/analyze-sample-code.dart
+++ b/dev/bots/analyze-sample-code.dart
@@ -193,7 +193,7 @@ class SampleChecker {
       "import 'dart:typed_data';",
       "import 'dart:ui' as ui;",
       "import 'package:flutter_test/flutter_test.dart';",
-      for (File file in _listDartFiles(Directory(_defaultFlutterPackage))) ...<String>[
+      for (final File file in _listDartFiles(Directory(_defaultFlutterPackage))) ...<String>[
         '',
         '// ${file.path}',
         "import 'package:flutter/${path.basename(file.path)}';",
@@ -214,7 +214,7 @@ class SampleChecker {
       errors = _analyze(_tempDirectory, sections, snippets);
     } finally {
       if (errors.isNotEmpty) {
-        for (String filePath in errors.keys) {
+        for (final String filePath in errors.keys) {
           errors[filePath].forEach(stderr.writeln);
         }
         stderr.writeln('\nFound ${errors.length} sample code errors.');
@@ -310,7 +310,7 @@ class SampleChecker {
     final List<Section> sections = <Section>[];
     final List<Snippet> snippets = <Snippet>[];
 
-    for (File file in _listDartFiles(_flutterPackage, recursive: true)) {
+    for (final File file in _listDartFiles(_flutterPackage, recursive: true)) {
       final String relativeFilePath = path.relative(file.path, from: _flutterPackage.path);
       final List<String> sampleLines = file.readAsLinesSync();
       final List<Section> preambleSections = <Section>[];
@@ -326,7 +326,7 @@ class SampleChecker {
       final List<String> block = <String>[];
       List<String> snippetArgs = <String>[];
       Line startLine;
-      for (String line in sampleLines) {
+      for (final String line in sampleLines) {
         lineNumber += 1;
         final String trimmedLine = line.trim();
         if (inSnippet) {
@@ -434,10 +434,10 @@ class SampleChecker {
       }
     }
     print('Found ${sections.length} sample code sections.');
-    for (Section section in sections) {
+    for (final Section section in sections) {
       sectionMap[_writeSection(section).path] = section;
     }
-    for (Snippet snippet in snippets) {
+    for (final Snippet snippet in snippets) {
       final File snippetFile = _writeSnippet(snippet);
       snippet.contents = snippetFile.readAsLinesSync();
       snippetMap[snippetFile.absolute.path] = snippet;
@@ -576,7 +576,7 @@ linter:
     );
     bool unknownAnalyzerErrors = false;
     final int headerLength = headers.length + 2;
-    for (String error in errors) {
+    for (final String error in errors) {
       final Match parts = errorPattern.matchAsPrefix(error);
       if (parts != null) {
         final String message = parts[2];
@@ -860,7 +860,7 @@ class Snippet {
   String toString() {
     final StringBuffer buf = StringBuffer('snippet ${args.join(' ')}\n');
     int count = start.line;
-    for (String line in input) {
+    for (final String line in input) {
       buf.writeln(' ${count.toString().padLeft(4, ' ')}: $line');
       count++;
     }
diff --git a/dev/bots/analyze.dart b/dev/bots/analyze.dart
index 1da04580298..f4a703c146a 100644
--- a/dev/bots/analyze.dart
+++ b/dev/bots/analyze.dart
@@ -147,11 +147,11 @@ final RegExp _grandfatheredDeprecation = RegExp(r' // ignore: flutter_deprecatio
 
 Future<void> verifyDeprecations(String workingDirectory, { int minimumMatches = 2000 }) async {
   final List<String> errors = <String>[];
-  for (File file in _allFiles(workingDirectory, 'dart', minimumMatches: minimumMatches)) {
+  for (final File file in _allFiles(workingDirectory, 'dart', minimumMatches: minimumMatches)) {
     int lineNumber = 0;
     final List<String> lines = file.readAsLinesSync();
     final List<int> linesWithDeprecations = <int>[];
-    for (String line in lines) {
+    for (final String line in lines) {
       if (line.contains(_findDeprecationPattern) &&
           !line.endsWith(_ignoreDeprecation) &&
           !line.contains(_grandfatheredDeprecation)) {
@@ -239,7 +239,7 @@ Future<void> _verifyNoMissingLicenseForExtension(String workingDirectory, String
   assert(!license.endsWith('\n'));
   final String licensePattern = license + '\n' + (trailingBlank ? '\n' : '');
   final List<String> errors = <String>[];
-  for (File file in _allFiles(workingDirectory, extension, minimumMatches: minimumMatches)) {
+  for (final File file in _allFiles(workingDirectory, extension, minimumMatches: minimumMatches)) {
     final String contents = file.readAsStringSync().replaceAll('\r\n', '\n');
     if (contents.isEmpty)
       continue; // let's not go down the /bin/true rabbit hole
@@ -270,8 +270,8 @@ Future<void> verifyNoTestImports(String workingDirectory) async {
   final List<String> errors = <String>[];
   assert("// foo\nimport 'binding_test.dart' as binding;\n'".contains(_testImportPattern));
   final List<File> dartFiles = _allFiles(path.join(workingDirectory, 'packages'), 'dart', minimumMatches: 1500).toList();
-  for (File file in dartFiles) {
-    for (String line in file.readAsLinesSync()) {
+  for (final File file in dartFiles) {
+    for (final String line in file.readAsLinesSync()) {
       final Match match = _testImportPattern.firstMatch(line);
       if (match != null && !_exemptTestImports.contains(match.group(2)))
         errors.add(file.path);
@@ -365,7 +365,7 @@ Future<void> verifyGeneratedPluginRegistrants(String flutterRoot) async {
 
   final Map<String, List<File>> packageToRegistrants = <String, List<File>>{};
 
-  for (File file in flutterRootDir.listSync(recursive: true).whereType<File>().where(_isGeneratedPluginRegistrant)) {
+  for (final File file in flutterRootDir.listSync(recursive: true).whereType<File>().where(_isGeneratedPluginRegistrant)) {
     final String package = _getPackageFor(file, flutterRootDir);
     final List<File> registrants = packageToRegistrants.putIfAbsent(package, () => <File>[]);
     registrants.add(file);
@@ -373,16 +373,16 @@ Future<void> verifyGeneratedPluginRegistrants(String flutterRoot) async {
 
   final Set<String> outOfDate = <String>{};
 
-  for (String package in packageToRegistrants.keys) {
+  for (final String package in packageToRegistrants.keys) {
     final Map<File, String> fileToContent = <File, String>{};
-    for (File f in packageToRegistrants[package]) {
+    for (final File f in packageToRegistrants[package]) {
       fileToContent[f] = f.readAsStringSync();
     }
     await runCommand(flutter, <String>['inject-plugins'],
       workingDirectory: package,
       outputMode: OutputMode.discard,
     );
-    for (File registrant in fileToContent.keys) {
+    for (final File registrant in fileToContent.keys) {
       if (registrant.readAsStringSync() != fileToContent[registrant]) {
         outOfDate.add(registrant.path);
       }
@@ -422,20 +422,20 @@ Future<void> verifyNoBadImportsInFlutter(String workingDirectory) async {
   }
   // Verify that the imports are well-ordered.
   final Map<String, Set<String>> dependencyMap = <String, Set<String>>{};
-  for (String directory in directories) {
+  for (final String directory in directories) {
     dependencyMap[directory] = _findFlutterDependencies(path.join(srcPath, directory), errors, checkForMeta: directory != 'foundation');
   }
   assert(dependencyMap['material'].contains('widgets') &&
          dependencyMap['widgets'].contains('rendering') &&
          dependencyMap['rendering'].contains('painting')); // to make sure we're convinced _findFlutterDependencies is finding some
-  for (String package in dependencyMap.keys) {
+  for (final String package in dependencyMap.keys) {
     if (dependencyMap[package].contains(package)) {
       errors.add(
         'One of the files in the $yellow$package$reset package imports that package recursively.'
       );
     }
   }
-  for (String package in dependencyMap.keys) {
+  for (final String package in dependencyMap.keys) {
     final List<String> loop = _deepSearch<String>(dependencyMap, package);
     if (loop != null) {
       errors.add(
@@ -459,7 +459,7 @@ Future<void> verifyNoBadImportsInFlutter(String workingDirectory) async {
 Future<void> verifyNoBadImportsInFlutterTools(String workingDirectory) async {
   final List<String> errors = <String>[];
   final List<File> files = _allFiles(path.join(workingDirectory, 'packages', 'flutter_tools', 'lib'), 'dart', minimumMatches: 200).toList();
-  for (File file in files) {
+  for (final File file in files) {
     if (file.readAsStringSync().contains('package:flutter_tools/')) {
       errors.add('$yellow${file.path}$reset imports flutter_tools.');
     }
@@ -535,7 +535,7 @@ Future<void> verifyNoTrailingSpaces(String workingDirectory, { int minimumMatche
     .where((File file) => path.extension(file.path) != '.jar')
     .toList();
   final List<String> problems = <String>[];
-  for (File file in files) {
+  for (final File file in files) {
     final List<String> lines = file.readAsLinesSync();
     for (int index = 0; index < lines.length; index += 1) {
       if (lines[index].endsWith(' ')) {
@@ -1004,7 +1004,7 @@ Future<void> verifyNoBinaries(String workingDirectory, { Set<Hash256> grandfathe
       .map<File>((String filename) => File(path.join(workingDirectory, filename)))
       .toList();
     final List<String> problems = <String>[];
-    for (File file in files) {
+    for (final File file in files) {
       final Uint8List bytes = file.readAsBytesSync();
       try {
         utf8.decode(bytes);
@@ -1156,7 +1156,7 @@ Set<String> _findFlutterDependencies(String srcPath, List<String> errors, { bool
   return _allFiles(srcPath, 'dart', minimumMatches: 1)
     .map<Set<String>>((File file) {
       final Set<String> result = <String>{};
-      for (String line in file.readAsLinesSync()) {
+      for (final String line in file.readAsLinesSync()) {
         Match match = _importPattern.firstMatch(line);
         if (match != null)
           result.add(match.group(2));
@@ -1180,7 +1180,7 @@ Set<String> _findFlutterDependencies(String srcPath, List<String> errors, { bool
 }
 
 List<T> _deepSearch<T>(Map<T, Set<T>> map, T start, [ Set<T> seen ]) {
-  for (T key in map[start]) {
+  for (final T key in map[start]) {
     if (key == start)
       continue; // we catch these separately
     if (seen != null && seen.contains(key))
diff --git a/dev/bots/flutter_compact_formatter.dart b/dev/bots/flutter_compact_formatter.dart
index 5a4bbf62154..0b5552c1ee1 100644
--- a/dev/bots/flutter_compact_formatter.dart
+++ b/dev/bots/flutter_compact_formatter.dart
@@ -160,7 +160,7 @@ class FlutterCompactFormatter {
   void finish() {
     final List<String> skipped = <String>[];
     final List<String> failed = <String>[];
-    for (TestResult result in _tests.values) {
+    for (final TestResult result in _tests.values) {
       switch (result.status) {
         case TestStatus.started:
           failed.add('${_red}Unexpectedly failed to complete a test!');
diff --git a/dev/bots/prepare_package.dart b/dev/bots/prepare_package.dart
index ce9bad72e67..b45bb1d6d66 100644
--- a/dev/bots/prepare_package.dart
+++ b/dev/bots/prepare_package.dart
@@ -354,7 +354,7 @@ class ArchiveCreator {
     // Create each of the templates, since they will call 'pub get' on
     // themselves when created, and this will warm the cache with their
     // dependencies too.
-    for (String template in <String>['app', 'package', 'plugin']) {
+    for (final String template in <String>['app', 'package', 'plugin']) {
       final String createName = path.join(tempDir.path, 'create_$template');
       await _runFlutter(
         <String>['create', '--template=$template', createName],
@@ -528,7 +528,7 @@ class ArchivePublisher {
     // Search for any entries with the same hash and channel and remove them.
     final List<dynamic> releases = jsonData['releases'] as List<dynamic>;
     jsonData['releases'] = <Map<String, dynamic>>[
-      for (Map<String, dynamic> entry in releases.cast<Map<String, dynamic>>())
+      for (final Map<String, dynamic> entry in releases.cast<Map<String, dynamic>>())
         if (entry['hash'] != newEntry['hash'] || entry['channel'] != newEntry['channel'])
           entry,
       newEntry,
diff --git a/dev/bots/run_command.dart b/dev/bots/run_command.dart
index 14070670576..2577433f36b 100644
--- a/dev/bots/run_command.dart
+++ b/dev/bots/run_command.dart
@@ -37,7 +37,7 @@ Stream<String> runAndGetStdout(String executable, List<String> arguments, {
 
   stderr.addStream(process.stderr);
   final Stream<String> lines = process.stdout.transform(utf8.decoder).transform(const LineSplitter());
-  await for (String line in lines)
+  await for (final String line in lines)
     yield line;
 
   final int exitCode = await process.exitCode;
diff --git a/dev/bots/test.dart b/dev/bots/test.dart
index 05fee88c753..92fd621b060 100644
--- a/dev/bots/test.dart
+++ b/dev/bots/test.dart
@@ -295,7 +295,7 @@ const List<String> _excludedExampleApplications = <String>[
 /// target app.
 Future<void> _runBuildTests() async {
   final Stream<FileSystemEntity> exampleDirectories = Directory(path.join(flutterRoot, 'examples')).list();
-  await for (FileSystemEntity fileEntity in exampleDirectories) {
+  await for (final FileSystemEntity fileEntity in exampleDirectories) {
     if (fileEntity is! Directory) {
       continue;
     }
@@ -817,7 +817,7 @@ Future<void> _runHostOnlyDeviceLabTests() async {
       last = '_last';
     }
     subshards['$subshard$last'] = () async {
-      for (ShardRunner test in sublist)
+      for (final ShardRunner test in sublist)
         await test();
     };
   }
@@ -1020,7 +1020,7 @@ Future<void> _runFromList(Map<String, ShardRunner> items, String key, String nam
     item = parts[positionInTaskName];
   }
   if (item == null) {
-    for (String currentItem in items.keys) {
+    for (final String currentItem in items.keys) {
       print('$bold$key=$currentItem$reset');
       await items[currentItem]();
       print('');
diff --git a/dev/bots/test/fake_process_manager.dart b/dev/bots/test/fake_process_manager.dart
index 521e8c25e63..04d2317225c 100644
--- a/dev/bots/test/fake_process_manager.dart
+++ b/dev/bots/test/fake_process_manager.dart
@@ -34,7 +34,7 @@ class FakeProcessManager extends Mock implements ProcessManager {
   Map<String, List<ProcessResult>> get fakeResults => _fakeResults;
   set fakeResults(Map<String, List<ProcessResult>> value) {
     _fakeResults = <String, List<ProcessResult>>{};
-    for (String key in value.keys) {
+    for (final String key in value.keys) {
       _fakeResults[key] = (value[key] ?? <ProcessResult>[ProcessResult(0, 0, '', '')]).toList();
     }
   }
@@ -46,7 +46,7 @@ class FakeProcessManager extends Mock implements ProcessManager {
   /// parameters were in the same order.
   void verifyCalls(List<String> calls) {
     int index = 0;
-    for (String call in calls) {
+    for (final String call in calls) {
       expect(call.split(' '), orderedEquals(invocations[index].positionalArguments[0] as Iterable<dynamic>));
       index++;
     }
@@ -178,7 +178,7 @@ class StringStreamConsumer implements StreamConsumer<List<int>> {
 
   @override
   Future<dynamic> close() async {
-    for (Completer<dynamic> completer in completers) {
+    for (final Completer<dynamic> completer in completers) {
       await completer.future;
     }
     completers.clear();
diff --git a/dev/bots/test/fake_process_manager_test.dart b/dev/bots/test/fake_process_manager_test.dart
index b74576c83af..6782c02d34c 100644
--- a/dev/bots/test/fake_process_manager_test.dart
+++ b/dev/bots/test/fake_process_manager_test.dart
@@ -34,7 +34,7 @@ void main() {
         ],
       };
       processManager.fakeResults = calls;
-      for (String key in calls.keys) {
+      for (final String key in calls.keys) {
         final Process process = await processManager.start(key.split(' '));
         String output = '';
         process.stdout.listen((List<int> item) {
@@ -56,7 +56,7 @@ void main() {
         ],
       };
       processManager.fakeResults = calls;
-      for (String key in calls.keys) {
+      for (final String key in calls.keys) {
         final ProcessResult result = await processManager.run(key.split(' '));
         expect(result.stdout, equals(calls[key][0].stdout));
       }
@@ -73,7 +73,7 @@ void main() {
         ],
       };
       processManager.fakeResults = calls;
-      for (String key in calls.keys) {
+      for (final String key in calls.keys) {
         final ProcessResult result = processManager.runSync(key.split(' '));
         expect(result.stdout, equals(calls[key][0].stdout));
       }
@@ -90,7 +90,7 @@ void main() {
         ],
       };
       processManager.fakeResults = calls;
-      for (String key in calls.keys) {
+      for (final String key in calls.keys) {
         final Process process = await processManager.start(key.split(' '));
         String output = '';
         process.stdout.listen((List<int> item) {
diff --git a/dev/bots/test/prepare_package_test.dart b/dev/bots/test/prepare_package_test.dart
index b7054fecae1..9f4a122fc6c 100644
--- a/dev/bots/test/prepare_package_test.dart
+++ b/dev/bots/test/prepare_package_test.dart
@@ -35,7 +35,7 @@ void main() {
       );
     }
   });
-  for (String platformName in <String>['macos', 'linux', 'windows']) {
+  for (final String platformName in <String>['macos', 'linux', 'windows']) {
     final FakePlatform platform = FakePlatform(
       operatingSystem: platformName,
       environment: <String, String>{
diff --git a/dev/bots/test/test_test.dart b/dev/bots/test/test_test.dart
index ce2e3fb7b3e..debf9ca52ed 100644
--- a/dev/bots/test/test_test.dart
+++ b/dev/bots/test/test_test.dart
@@ -27,7 +27,7 @@ void main() {
         '1.2.3+hotfix.1',
         '1.2.3+hotfix.12-pre.12',
       ];
-      for (String version in valid_versions) {
+      for (final String version in valid_versions) {
         when(file.readAsString()).thenAnswer((Invocation invocation) => Future<String>.value(version));
         expect(
           await verifyVersion(file),
@@ -47,7 +47,7 @@ void main() {
         '  1.2.3',
         '1.2.3-hotfix.1',
       ];
-      for (String version in invalid_versions) {
+      for (final String version in invalid_versions) {
         when(file.readAsString()).thenAnswer((Invocation invocation) => Future<String>.value(version));
         expect(
           await verifyVersion(file),
diff --git a/dev/bots/unpublish_package.dart b/dev/bots/unpublish_package.dart
index 3da5bf6f00e..581cd8f66c9 100644
--- a/dev/bots/unpublish_package.dart
+++ b/dev/bots/unpublish_package.dart
@@ -254,7 +254,7 @@ class ArchiveUnpublisher {
       return bDate.compareTo(aDate);
     });
     jsonData['releases'] = releases;
-    for (Channel channel in channels) {
+    for (final Channel channel in channels) {
       if (!revisionsBeingRemoved.contains(jsonData['current_release'][getChannelName(channel)])) {
         // Don't replace the current release if it's not one of the revisions we're removing.
         continue;
@@ -276,7 +276,7 @@ class ArchiveUnpublisher {
   Future<Map<Channel, Map<String, String>>> _getArchivePaths(List<Map<String, String>> releases) async {
     final Set<String> hashes = <String>{};
     final Map<Channel, Map<String, String>> paths = <Channel, Map<String, String>>{};
-    for (Map<String, String> revision in releases) {
+    for (final Map<String, String> revision in releases) {
       final String hash = revision['hash'];
       final Channel channel = fromChannelName(revision['channel']);
       hashes.add(hash);
@@ -350,9 +350,9 @@ class ArchiveUnpublisher {
   Future<void> _cloudRemoveArchive(Map<Channel, Map<String, String>> paths) async {
     final List<String> files = <String>[];
     print('${confirmed ? 'Removing' : 'Would remove'} the following release archives:');
-    for (Channel channel in paths.keys) {
+    for (final Channel channel in paths.keys) {
       final Map<String, String> hashes = paths[channel];
-      for (String hash in hashes.keys) {
+      for (final String hash in hashes.keys) {
         final String file = '$gsReleaseFolder/${hashes[hash]}';
         files.add(file);
         print('  $file');
@@ -464,7 +464,7 @@ Future<void> main(List<String> rawArguments) async {
   if (revisions.isEmpty) {
     errorExit('Invalid argument: at least one --revision must be specified.');
   }
-  for (String revision in revisions) {
+  for (final String revision in revisions) {
     if (revision.length != 40) {
       errorExit('Invalid argument: --revision "$revision" must be the entire hash, not just a prefix.');
     }
@@ -500,7 +500,7 @@ Future<void> main(List<String> rawArguments) async {
   String message;
   String stack;
   try {
-    for (PublishedPlatform platform in platforms) {
+    for (final PublishedPlatform platform in platforms) {
       final ArchiveUnpublisher publisher = ArchiveUnpublisher(
         tempDir,
         revisions.toSet(),
diff --git a/dev/customer_testing/run_tests.dart b/dev/customer_testing/run_tests.dart
index 008789206c0..62133a4fd9e 100644
--- a/dev/customer_testing/run_tests.dart
+++ b/dev/customer_testing/run_tests.dart
@@ -102,7 +102,7 @@ Future<bool> run(List<String> arguments) async {
     print('');
   }
 
-  for (File file in files) {
+  for (final File file in files) {
     if (verbose)
       print('Processing ${file.path}...');
     TestFile instructions;
@@ -127,7 +127,7 @@ Future<bool> run(List<String> arguments) async {
     try {
       bool success;
       bool showContacts = false;
-      for (String fetchCommand in instructions.fetch) {
+      for (final String fetchCommand in instructions.fetch) {
         success = await shell(fetchCommand, checkout, verbose: verbose, silentFailure: skipOnFetchFailure);
         if (!success) {
           if (skipOnFetchFailure) {
@@ -153,7 +153,7 @@ Future<bool> run(List<String> arguments) async {
         for (int iteration = 0; iteration < repeat; iteration += 1) {
           if (verbose && repeat > 1)
             print('Round ${iteration + 1} of $repeat.');
-          for (String testCommand in instructions.tests) {
+          for (final String testCommand in instructions.tests) {
             success = await shell(testCommand, tests, verbose: verbose);
             if (!success) {
               print('ERROR: One or more tests from ${path.basenameWithoutExtension(file.path)} failed.');
@@ -197,7 +197,7 @@ class TestFile {
     final List<String> fetch = <String>[];
     final List<Directory> update = <Directory>[];
     final List<String> test = <String>[];
-    for (String line in file.readAsLinesSync().map((String line) => line.trim())) {
+    for (final String line in file.readAsLinesSync().map((String line) => line.trim())) {
       if (line.isEmpty) {
         // blank line
       } else if (line.startsWith('#')) {
@@ -228,7 +228,7 @@ class TestFile {
     }
     if (contacts.isEmpty)
       throw FormatException('${errorPrefix}No contacts specified. At least one contact e-mail address must be specified.');
-    for (String email in contacts) {
+    for (final String email in contacts) {
       if (!email.contains(_email) || email.endsWith('@example.com'))
         throw FormatException('${errorPrefix}The following e-mail address appears to be an invalid e-mail address: $email');
     }
diff --git a/dev/devicelab/bin/run.dart b/dev/devicelab/bin/run.dart
index 9eaa691f399..cc2af6221c9 100644
--- a/dev/devicelab/bin/run.dart
+++ b/dev/devicelab/bin/run.dart
@@ -59,7 +59,7 @@ Future<void> main(List<String> rawArgs) async {
   final String localEngine = args['local-engine'] as String;
   final String localEngineSrcPath = args['local-engine-src-path'] as String;
 
-  for (String taskName in _taskNames) {
+  for (final String taskName in _taskNames) {
     section('Running task "$taskName"');
     final Map<String, dynamic> result = await runTask(
       taskName,
@@ -95,7 +95,7 @@ void addTasks({
   }
   // Only start skipping if user specified a task to continue from
   final String stage = args['stage'] as String;
-  for (ManifestTask task in tasks) {
+  for (final ManifestTask task in tasks) {
     final bool isQualifyingStage = stage == null || task.stage == stage;
     final bool isQualifyingHost = !(args['match-host-platform'] as bool) || task.isSupportedByHost();
     if (isQualifyingHost && isQualifyingStage) {
@@ -116,7 +116,7 @@ final ArgParser _argParser = ArgParser()
         '\n'
         'This option may be repeated to specify multiple tasks.',
     callback: (List<String> value) {
-      for (String nameOrPath in value) {
+      for (final String nameOrPath in value) {
         final List<String> fragments = path.split(nameOrPath);
         final bool isDartFile = fragments.last.endsWith('.dart');
 
diff --git a/dev/devicelab/bin/tasks/build_ios_framework_module_test.dart b/dev/devicelab/bin/tasks/build_ios_framework_module_test.dart
index 99e6c0e5a59..726ea1708dc 100644
--- a/dev/devicelab/bin/tasks/build_ios_framework_module_test.dart
+++ b/dev/devicelab/bin/tasks/build_ios_framework_module_test.dart
@@ -114,7 +114,7 @@ Future<void> main() async {
 
       section('Check profile, release builds has Dart AOT dylib');
 
-      for (String mode in <String>['Profile', 'Release']) {
+      for (final String mode in <String>['Profile', 'Release']) {
         final String appFrameworkPath = path.join(
           outputPath,
           mode,
@@ -159,7 +159,7 @@ Future<void> main() async {
 
       section("Check all modes' engine dylib");
 
-      for (String mode in <String>['Debug', 'Profile', 'Release']) {
+      for (final String mode in <String>['Debug', 'Profile', 'Release']) {
         final String engineFrameworkPath = path.join(
           outputPath,
           mode,
@@ -194,7 +194,7 @@ Future<void> main() async {
 
       section("Check all modes' engine header");
 
-      for (String mode in <String>['Debug', 'Profile', 'Release']) {
+      for (final String mode in <String>['Debug', 'Profile', 'Release']) {
         checkFileContains(
           <String>['#include "FlutterEngine.h"'],
           path.join(outputPath, mode, 'Flutter.framework', 'Headers', 'Flutter.h'),
@@ -203,7 +203,7 @@ Future<void> main() async {
 
       section("Check all modes' have plugin dylib");
 
-      for (String mode in <String>['Debug', 'Profile', 'Release']) {
+      for (final String mode in <String>['Debug', 'Profile', 'Release']) {
         final String pluginFrameworkPath = path.join(
           outputPath,
           mode,
@@ -237,7 +237,7 @@ Future<void> main() async {
 
       section("Check all modes' have generated plugin registrant");
 
-      for (String mode in <String>['Debug', 'Profile', 'Release']) {
+      for (final String mode in <String>['Debug', 'Profile', 'Release']) {
         final String registrantFrameworkPath = path.join(
           outputPath,
           mode,
diff --git a/dev/devicelab/bin/tasks/dartdocs.dart b/dev/devicelab/bin/tasks/dartdocs.dart
index 3bcaff66484..4173a7b54bd 100644
--- a/dev/devicelab/bin/tasks/dartdocs.dart
+++ b/dev/devicelab/bin/tasks/dartdocs.dart
@@ -40,7 +40,7 @@ Future<void> main() async {
         print('^ not sure what to do with that line ^');
       }
     }
-    await for (String entry in analysis.stderr.transform<String>(utf8.decoder).transform<String>(const LineSplitter())) {
+    await for (final String entry in analysis.stderr.transform<String>(utf8.decoder).transform<String>(const LineSplitter())) {
       print('analyzer stderr: $entry');
       if (entry.contains(' (ran in ') && !sawFinalLine) {
         // ignore this line once
diff --git a/dev/devicelab/bin/tasks/flutter_gallery__transition_perf_with_semantics.dart b/dev/devicelab/bin/tasks/flutter_gallery__transition_perf_with_semantics.dart
index e201e52d10c..8bf7c0a96fc 100644
--- a/dev/devicelab/bin/tasks/flutter_gallery__transition_perf_with_semantics.dart
+++ b/dev/devicelab/bin/tasks/flutter_gallery__transition_perf_with_semantics.dart
@@ -16,7 +16,7 @@ Future<void> main() async {
 
     final List<String> benchmarkScoreKeys = <String>[];
     final Map<String, dynamic> data = <String, dynamic>{};
-    for (String key in withSemantics.benchmarkScoreKeys) {
+    for (final String key in withSemantics.benchmarkScoreKeys) {
       final String deltaKey = 'delta_$key';
       data[deltaKey] = withSemantics.data[key] - withoutSemantics.data[key];
       data['semantics_$key'] = withSemantics.data[key];
diff --git a/dev/devicelab/bin/tasks/flutter_test_performance.dart b/dev/devicelab/bin/tasks/flutter_test_performance.dart
index cba5b254176..540fdb5a3e4 100644
--- a/dev/devicelab/bin/tasks/flutter_test_performance.dart
+++ b/dev/devicelab/bin/tasks/flutter_test_performance.dart
@@ -49,7 +49,7 @@ Future<int> runTest({bool coverage = false}) async {
   );
   int badLines = 0;
   TestStep step = TestStep.starting;
-  await for (String entry in analysis.stdout.transform<String>(utf8.decoder).transform<String>(const LineSplitter())) {
+  await for (final String entry in analysis.stdout.transform<String>(utf8.decoder).transform<String>(const LineSplitter())) {
     print('test stdout ($step): $entry');
     if (step == TestStep.starting && entry == 'Building flutter tool...') {
       // ignore this line
@@ -82,7 +82,7 @@ Future<int> runTest({bool coverage = false}) async {
       }
     }
   }
-  await for (String entry in analysis.stderr.transform<String>(utf8.decoder).transform<String>(const LineSplitter())) {
+  await for (final String entry in analysis.stderr.transform<String>(utf8.decoder).transform<String>(const LineSplitter())) {
     print('test stderr: $entry');
     badLines += 1;
   }
diff --git a/dev/devicelab/bin/tasks/gradle_non_android_plugin_test.dart b/dev/devicelab/bin/tasks/gradle_non_android_plugin_test.dart
index 594644fe7cf..56f9faa2649 100644
--- a/dev/devicelab/bin/tasks/gradle_non_android_plugin_test.dart
+++ b/dev/devicelab/bin/tasks/gradle_non_android_plugin_test.dart
@@ -50,7 +50,7 @@ Future<void> main() async {
       final String pubspecString = pubspecFile.readAsStringSync();
 
       final StringBuffer iosOnlyPubspec = StringBuffer();
-      for (String line in pubspecString.split('\n')) {
+      for (final String line in pubspecString.split('\n')) {
         if (line.startsWith('    androidPackage:')) {
           continue;
         }
diff --git a/dev/devicelab/bin/tasks/technical_debt__cost.dart b/dev/devicelab/bin/tasks/technical_debt__cost.dart
index c22f834d883..8f04c69a0c2 100644
--- a/dev/devicelab/bin/tasks/technical_debt__cost.dart
+++ b/dev/devicelab/bin/tasks/technical_debt__cost.dart
@@ -37,7 +37,7 @@ Future<double> findCostsForFile(File file) async {
     return 0.0;
   final bool isTest = file.path.endsWith('_test.dart');
   double total = 0.0;
-  for (String line in await file.readAsLines()) {
+  for (final String line in await file.readAsLines()) {
     if (line.contains(todoPattern))
       total += todoCost;
     if (line.contains(ignorePattern))
@@ -60,7 +60,7 @@ Future<int> findGlobalsForFile(File file) async {
   if (path.extension(file.path) != '.dart')
     return 0;
   int total = 0;
-  for (String line in await file.readAsLines()) {
+  for (final String line in await file.readAsLines()) {
     if (line.contains(globalsPattern))
       total += 1;
   }
@@ -74,7 +74,7 @@ Future<double> findCostsForRepo() async {
     workingDirectory: flutterDirectory.path,
   );
   double total = 0.0;
-  await for (String entry in git.stdout.transform<String>(utf8.decoder).transform<String>(const LineSplitter()))
+  await for (final String entry in git.stdout.transform<String>(utf8.decoder).transform<String>(const LineSplitter()))
     total += await findCostsForFile(File(path.join(flutterDirectory.path, entry)));
   final int gitExitCode = await git.exitCode;
   if (gitExitCode != 0)
@@ -89,7 +89,7 @@ Future<int> findGlobalsForTool() async {
     workingDirectory: flutterDirectory.path,
   );
   int total = 0;
-  await for (String entry in git.stdout.transform<String>(utf8.decoder).transform<String>(const LineSplitter()))
+  await for (final String entry in git.stdout.transform<String>(utf8.decoder).transform<String>(const LineSplitter()))
     total += await findGlobalsForFile(File(path.join(flutterDirectory.path, entry)));
   final int gitExitCode = await git.exitCode;
   if (gitExitCode != 0)
diff --git a/dev/devicelab/bin/tasks/uncaught_image_error_linux.dart b/dev/devicelab/bin/tasks/uncaught_image_error_linux.dart
index 7c647ff5f19..17f55c58bb4 100644
--- a/dev/devicelab/bin/tasks/uncaught_image_error_linux.dart
+++ b/dev/devicelab/bin/tasks/uncaught_image_error_linux.dart
@@ -37,7 +37,7 @@ Future<void> main() async {
         .transform(utf8.decoder)
         .transform(const LineSplitter());
 
-      await for (String line in lines) {
+      await for (final String line in lines) {
         print(line);
         if (line.contains('ERROR caught by framework')) {
           passed = true;
diff --git a/dev/devicelab/lib/framework/adb.dart b/dev/devicelab/lib/framework/adb.dart
index fa07a86ec54..ead98839590 100644
--- a/dev/devicelab/lib/framework/adb.dart
+++ b/dev/devicelab/lib/framework/adb.dart
@@ -144,7 +144,7 @@ class AndroidDeviceDiscovery implements DeviceDiscovery {
     final List<String> output = (await eval(adbPath, <String>['devices', '-l'], canFail: false))
         .trim().split('\n');
     final List<String> results = <String>[];
-    for (String line in output) {
+    for (final String line in output) {
       // Skip lines like: * daemon started successfully *
       if (line.startsWith('* daemon '))
         continue;
@@ -172,7 +172,7 @@ class AndroidDeviceDiscovery implements DeviceDiscovery {
   @override
   Future<Map<String, HealthCheckResult>> checkDevices() async {
     final Map<String, HealthCheckResult> results = <String, HealthCheckResult>{};
-    for (String deviceId in await discoverDevices()) {
+    for (final String deviceId in await discoverDevices()) {
       try {
         final AndroidDevice device = AndroidDevice(deviceId: deviceId);
         // Just a smoke test that we can read wakefulness state
@@ -432,7 +432,7 @@ class IosDeviceDiscovery implements DeviceDiscovery {
   @override
   Future<Map<String, HealthCheckResult>> checkDevices() async {
     final Map<String, HealthCheckResult> results = <String, HealthCheckResult>{};
-    for (String deviceId in await discoverDevices()) {
+    for (final String deviceId in await discoverDevices()) {
       // TODO(ianh): do a more meaningful connectivity check than just recording the ID
       results['ios-device-$deviceId'] = HealthCheckResult.success();
     }
diff --git a/dev/devicelab/lib/framework/apk_utils.dart b/dev/devicelab/lib/framework/apk_utils.dart
index 2312672448d..ed83e839687 100644
--- a/dev/devicelab/lib/framework/apk_utils.dart
+++ b/dev/devicelab/lib/framework/apk_utils.dart
@@ -191,7 +191,7 @@ Future<String> getAndroidManifest(String apk) async {
  /// Checks that the classes are contained in the APK, throws otherwise.
 Future<void> checkApkContainsClasses(File apk, List<String> classes) async {
   final ApkExtractor extractor = ApkExtractor(apk);
-  for (String className in classes) {
+  for (final String className in classes) {
     if (!(await extractor.containsClass(className))) {
       throw Exception('APK doesn\'t contain class `$className`.');
     }
diff --git a/dev/devicelab/lib/framework/framework.dart b/dev/devicelab/lib/framework/framework.dart
index e991c344852..45381ff8f96 100644
--- a/dev/devicelab/lib/framework/framework.dart
+++ b/dev/devicelab/lib/framework/framework.dart
@@ -179,7 +179,7 @@ class TaskResult {
         message = 'success' {
     const JsonEncoder prettyJson = JsonEncoder.withIndent('  ');
     if (benchmarkScoreKeys != null) {
-      for (String key in benchmarkScoreKeys) {
+      for (final String key in benchmarkScoreKeys) {
         if (!data.containsKey(key)) {
           throw 'Invalid Golem score key "$key". It does not exist in task '
               'result data ${prettyJson.convert(data)}';
diff --git a/dev/devicelab/lib/framework/manifest.dart b/dev/devicelab/lib/framework/manifest.dart
index 6263a06dbee..04b48b74eea 100644
--- a/dev/devicelab/lib/framework/manifest.dart
+++ b/dev/devicelab/lib/framework/manifest.dart
@@ -160,7 +160,7 @@ void _checkIsNotBlank(dynamic value, String variableName, String ownerName) {
 }
 
 void _checkKeys(Map<dynamic, dynamic> map, String variableName, List<String> allowedKeys) {
-  for (String key in map.keys.cast<String>()) {
+  for (final String key in map.keys.cast<String>()) {
     if (!allowedKeys.contains(key)) {
       throw ManifestError(
         'Unrecognized property "$key" in $variableName. '
diff --git a/dev/devicelab/lib/framework/running_processes.dart b/dev/devicelab/lib/framework/running_processes.dart
index e438b1814b2..cb09cf56c0a 100644
--- a/dev/devicelab/lib/framework/running_processes.dart
+++ b/dev/devicelab/lib/framework/running_processes.dart
@@ -100,7 +100,7 @@ Stream<RunningProcessInfo> windowsRunningProcesses(String processName) async* {
     print(result.stdout);
     return;
   }
-  for (RunningProcessInfo info in processPowershellOutput(result.stdout as String)) {
+  for (final RunningProcessInfo info in processPowershellOutput(result.stdout as String)) {
     yield info;
   }
 }
@@ -122,7 +122,7 @@ Iterable<RunningProcessInfo> processPowershellOutput(String output) sync* {
   int creationDateHeaderEnd;
   int commandLineHeaderStart;
   bool inTableBody = false;
-  for (String line in output.split('\n')) {
+  for (final String line in output.split('\n')) {
     if (line.startsWith('ProcessId')) {
       commandLineHeaderStart = line.indexOf('CommandLine');
       creationDateHeaderEnd = commandLineHeaderStart - 1;
@@ -191,7 +191,7 @@ Stream<RunningProcessInfo> posixRunningProcesses(
     print(result.stdout);
     return;
   }
-  for (RunningProcessInfo info in processPsOutput(result.stdout as String, processName)) {
+  for (final RunningProcessInfo info in processPsOutput(result.stdout as String, processName)) {
     yield info;
   }
 }
diff --git a/dev/devicelab/lib/framework/utils.dart b/dev/devicelab/lib/framework/utils.dart
index 9aa71be3ccb..2b54cc559b7 100644
--- a/dev/devicelab/lib/framework/utils.dart
+++ b/dev/devicelab/lib/framework/utils.dart
@@ -63,7 +63,7 @@ class HealthCheckResult {
     if (details != null && details.trim().isNotEmpty) {
       buf.writeln();
       // Indent details by 4 spaces
-      for (String line in details.trim().split('\n')) {
+      for (final String line in details.trim().split('\n')) {
         buf.writeln('    $line');
       }
     }
@@ -119,7 +119,7 @@ void recursiveCopy(Directory source, Directory target) {
   if (!target.existsSync())
     target.createSync();
 
-  for (FileSystemEntity entity in source.listSync(followLinks: false)) {
+  for (final FileSystemEntity entity in source.listSync(followLinks: false)) {
     final String name = path.basename(entity.path);
     if (entity is Directory && !entity.path.contains('.dart_tool'))
       recursiveCopy(entity, Directory(path.join(target.path, name)));
@@ -286,7 +286,7 @@ Future<void> forceQuitRunningProcesses() async {
   await Future<void>.delayed(const Duration(seconds: 1));
 
   // Whatever's left, kill it.
-  for (ProcessInfo p in _runningProcesses) {
+  for (final ProcessInfo p in _runningProcesses) {
     print('Force-quitting process:\n$p');
     if (!p.process.kill()) {
       print('Failed to force quit process');
@@ -636,7 +636,7 @@ void checkFileNotExists(String file) {
 
 /// Check that `collection` contains all entries in `values`.
 void checkCollectionContains<T>(Iterable<T> values, Iterable<T> collection) {
-  for (T value in values) {
+  for (final T value in values) {
     if (!collection.contains(value)) {
       throw TaskResult.failure('Expected to find `$value` in `${collection.toString()}`.');
     }
@@ -645,7 +645,7 @@ void checkCollectionContains<T>(Iterable<T> values, Iterable<T> collection) {
 
 /// Check that `collection` does not contain any entries in `values`
 void checkCollectionDoesNotContain<T>(Iterable<T> values, Iterable<T> collection) {
-  for (T value in values) {
+  for (final T value in values) {
     if (collection.contains(value)) {
       throw TaskResult.failure('Did not expect to find `$value` in `$collection`.');
     }
@@ -656,7 +656,7 @@ void checkCollectionDoesNotContain<T>(Iterable<T> values, Iterable<T> collection
 /// [Pattern]s, otherwise throws a [TaskResult].
 void checkFileContains(List<Pattern> patterns, String filePath) {
   final String fileContent = File(filePath).readAsStringSync();
-  for (Pattern pattern in patterns) {
+  for (final Pattern pattern in patterns) {
     if (!fileContent.contains(pattern)) {
       throw TaskResult.failure(
         'Expected to find `$pattern` in `$filePath` '
diff --git a/dev/devicelab/lib/tasks/gallery.dart b/dev/devicelab/lib/tasks/gallery.dart
index e27b9bce488..ae44b771840 100644
--- a/dev/devicelab/lib/tasks/gallery.dart
+++ b/dev/devicelab/lib/tasks/gallery.dart
@@ -50,7 +50,7 @@ class GalleryTransitionTest {
       file('${galleryDirectory.path}/build/transition_durations.timeline.json').readAsStringSync(),
     ) as Map<String, dynamic>;
     final Map<String, List<int>> transitions = <String, List<int>>{};
-    for (String key in original.keys) {
+    for (final String key in original.keys) {
       transitions[key.replaceAll('/', '')] = List<int>.from(original[key] as List<dynamic>);
     }
 
diff --git a/dev/devicelab/lib/tasks/perf_tests.dart b/dev/devicelab/lib/tasks/perf_tests.dart
index a1ad8fd14c5..7ced54f559f 100644
--- a/dev/devicelab/lib/tasks/perf_tests.dart
+++ b/dev/devicelab/lib/tasks/perf_tests.dart
@@ -386,7 +386,7 @@ class CompileTest {
 
     final RegExp metricExpression = RegExp(r'([a-zA-Z]+)\(CodeSize\)\: (\d+)');
     final Map<String, dynamic> metrics = <String, dynamic>{};
-    for (Match m in metricExpression.allMatches(compileLog)) {
+    for (final Match m in metricExpression.allMatches(compileLog)) {
       metrics[_sdkNameToMetricName(m.group(1))] = int.parse(m.group(2));
     }
     if (metrics.length != _kSdkNameToMetricNameMapping.length) {
diff --git a/dev/devicelab/lib/tasks/plugin_tests.dart b/dev/devicelab/lib/tasks/plugin_tests.dart
index ab04539bc26..cff0a7fbb9c 100644
--- a/dev/devicelab/lib/tasks/plugin_tests.dart
+++ b/dev/devicelab/lib/tasks/plugin_tests.dart
@@ -12,7 +12,7 @@ import 'package:flutter_devicelab/framework/utils.dart';
 /// Combines several TaskFunctions with trivial success value into one.
 TaskFunction combine(List<TaskFunction> tasks) {
   return () async {
-    for (TaskFunction task in tasks) {
+    for (final TaskFunction task in tasks) {
       final TaskResult result = await task();
       if (result.failed) {
         return result;
diff --git a/dev/devicelab/lib/tasks/save_catalog_screenshots.dart b/dev/devicelab/lib/tasks/save_catalog_screenshots.dart
index 062c0b49e74..214e2405096 100644
--- a/dev/devicelab/lib/tasks/save_catalog_screenshots.dart
+++ b/dev/devicelab/lib/tasks/save_catalog_screenshots.dart
@@ -120,14 +120,14 @@ Future<void> saveCatalogScreenshots({
     String prefix, // Prefix for all file names.
   }) async {
   final List<String> screenshots = <String>[
-    for (FileSystemEntity entity in directory.listSync())
+    for (final FileSystemEntity entity in directory.listSync())
       if (entity is File && entity.path.endsWith('.png'))
         entity.path,
   ];
 
   final List<String> largeNames = <String>[]; // Cloud storage names for the full res screenshots.
   final List<String> smallNames = <String>[]; // Likewise for the scaled down screenshots.
-  for (String path in screenshots) {
+  for (final String path in screenshots) {
     final String name = screenshotName(path);
     largeNames.add('$commit/$prefix$name.png');
     smallNames.add('$commit/$prefix${name}_small.png');
diff --git a/dev/devicelab/test/manifest_test.dart b/dev/devicelab/test/manifest_test.dart
index 4a642fe1985..8282a9f2491 100644
--- a/dev/devicelab/test/manifest_test.dart
+++ b/dev/devicelab/test/manifest_test.dart
@@ -19,7 +19,7 @@ void main() {
       expect(task.stage, 'devicelab');
       expect(task.requiredAgentCapabilities, <String>['linux/android']);
 
-      for (ManifestTask task in manifest.tasks) {
+      for (final ManifestTask task in manifest.tasks) {
         final File taskFile = File('bin/tasks/${task.name}.dart');
         expect(taskFile.existsSync(), true,
           reason: 'File ${taskFile.path} corresponding to manifest task "${task.name}" not found');
diff --git a/dev/devicelab/test/run_test.dart b/dev/devicelab/test/run_test.dart
index 90f43f382fc..809059001df 100644
--- a/dev/devicelab/test/run_test.dart
+++ b/dev/devicelab/test/run_test.dart
@@ -19,7 +19,7 @@ void main() {
       final ProcessResult scriptProcess = processManager.runSync(<String>[
         dart,
         'bin/run.dart',
-        for (String testName in testNames) ...<String>['-t', testName],
+        for (final String testName in testNames) ...<String>['-t', testName],
       ]);
       return scriptProcess;
     }
diff --git a/dev/integration_tests/android_semantics_testing/lib/src/common.dart b/dev/integration_tests/android_semantics_testing/lib/src/common.dart
index 06fa05f0529..79cf2f47ef4 100644
--- a/dev/integration_tests/android_semantics_testing/lib/src/common.dart
+++ b/dev/integration_tests/android_semantics_testing/lib/src/common.dart
@@ -149,7 +149,7 @@ class AndroidSemanticsNode  {
 
   /// Gets a list of [AndroidSemanticsActions] which are defined for the node.
   List<AndroidSemanticsAction> getActions() => <AndroidSemanticsAction>[
-    for (int id in (_values['actions'] as List<dynamic>).cast<int>()) AndroidSemanticsAction.deserialize(id),
+    for (final int id in (_values['actions'] as List<dynamic>).cast<int>()) AndroidSemanticsAction.deserialize(id),
   ];
 
   @override
diff --git a/dev/integration_tests/android_semantics_testing/test_driver/main_test.dart b/dev/integration_tests/android_semantics_testing/test_driver/main_test.dart
index fe759fe87d4..ef760023fb3 100644
--- a/dev/integration_tests/android_semantics_testing/test_driver/main_test.dart
+++ b/dev/integration_tests/android_semantics_testing/test_driver/main_test.dart
@@ -399,7 +399,7 @@ void main() {
           // catch up.
           await Future<void>.delayed(const Duration(milliseconds: 1500));
 
-          for (String item in popupItems) {
+          for (final String item in popupItems) {
             expect(
                 await getSemantics(find.byValueKey('$popupKeyValue.$item')),
                 hasAndroidSemantics(
@@ -423,7 +423,7 @@ void main() {
           await driver.tap(find.byValueKey(popupButtonKeyValue));
           await Future<void>.delayed(const Duration(milliseconds: 1500));
 
-          for (String item in popupItems) {
+          for (final String item in popupItems) {
             expect(
                 await getSemantics(find.byValueKey('$popupKeyValue.$item')),
                 hasAndroidSemantics(
@@ -467,7 +467,7 @@ void main() {
         try {
           await Future<void>.delayed(const Duration(milliseconds: 1500));
 
-          for (String item in popupItems) {
+          for (final String item in popupItems) {
             // There are two copies of each item, so we want to find the version
             // that is in the overlay, not the one in the dropdown.
             expect(
@@ -503,7 +503,7 @@ void main() {
           await driver.tap(find.byValueKey(dropdownButtonKeyValue));
           await Future<void>.delayed(const Duration(milliseconds: 1500));
 
-          for (String item in popupItems) {
+          for (final String item in popupItems) {
             // There are two copies of each item, so we want to find the version
             // that is in the overlay, not the one in the dropdown.
             expect(
@@ -572,7 +572,7 @@ void main() {
               ),
               reason: "Alert OK button doesn't have the right semantics");
 
-          for (String item in <String>['Title', 'Body1', 'Body2']) {
+          for (final String item in <String>['Title', 'Body1', 'Body2']) {
             expect(
                 await getSemantics(find.byValueKey('$alertKeyValue.$item')),
                 hasAndroidSemantics(
@@ -611,7 +611,7 @@ void main() {
               ),
               reason: "Alert OK button doesn't have the right semantics");
 
-          for (String item in <String>['Title', 'Body1', 'Body2']) {
+          for (final String item in <String>['Title', 'Body1', 'Body2']) {
             expect(
                 await getSemantics(find.byValueKey('$alertKeyValue.$item')),
                 hasAndroidSemantics(
diff --git a/dev/integration_tests/android_views/lib/motion_event_diff.dart b/dev/integration_tests/android_views/lib/motion_event_diff.dart
index f5f073fd480..b42d9e88157 100644
--- a/dev/integration_tests/android_views/lib/motion_event_diff.dart
+++ b/dev/integration_tests/android_views/lib/motion_event_diff.dart
@@ -122,7 +122,7 @@ void diffMaps(
         '${messagePrefix}keys (expected: ${expected.keys} actual: ${actual.keys} ');
     return;
   }
-  for (String key in expected.keys) {
+  for (final String key in expected.keys) {
     if (excludeKeys.contains(key))
       continue;
     if (doublesApproximatelyMatch(expected[key], actual[key]))
diff --git a/dev/integration_tests/android_views/lib/motion_events_page.dart b/dev/integration_tests/android_views/lib/motion_events_page.dart
index 48be7dea52e..a4b508b0a1c 100644
--- a/dev/integration_tests/android_views/lib/motion_events_page.dart
+++ b/dev/integration_tests/android_views/lib/motion_events_page.dart
@@ -123,7 +123,7 @@ class MotionEventsBodyState extends State<MotionEventsBody> {
       await channel.invokeMethod<void>('pipeFlutterViewEvents');
       await viewChannel.invokeMethod<void>('pipeTouchEvents');
       print('replaying ${recordedEvents.length} motion events');
-      for (Map<String, dynamic> event in recordedEvents.reversed) {
+      for (final Map<String, dynamic> event in recordedEvents.reversed) {
         await channel.invokeMethod<void>('synthesizeEvent', event);
       }
 
diff --git a/dev/integration_tests/channels/lib/src/test_step.dart b/dev/integration_tests/channels/lib/src/test_step.dart
index 4662d0338db..2a264671873 100644
--- a/dev/integration_tests/channels/lib/src/test_step.dart
+++ b/dev/integration_tests/channels/lib/src/test_step.dart
@@ -174,7 +174,7 @@ bool _deepEqualsList(List<dynamic> a, List<dynamic> b) {
 bool _deepEqualsMap(Map<dynamic, dynamic> a, Map<dynamic, dynamic> b) {
   if (a.length != b.length)
     return false;
-  for (dynamic key in a.keys) {
+  for (final dynamic key in a.keys) {
     if (!b.containsKey(key) || !_deepEquals(a[key], b[key]))
       return false;
   }
diff --git a/dev/manual_tests/lib/actions.dart b/dev/manual_tests/lib/actions.dart
index 16acf1ef121..2663b54c5ac 100644
--- a/dev/manual_tests/lib/actions.dart
+++ b/dev/manual_tests/lib/actions.dart
@@ -77,7 +77,7 @@ class UndoableActionDispatcher extends ActionDispatcher implements Listenable {
   /// May only be called by subclasses.
   @protected
   void notifyListeners() {
-    for (VoidCallback callback in _listeners) {
+    for (final VoidCallback callback in _listeners) {
       callback();
     }
   }
diff --git a/dev/manual_tests/lib/overlay_geometry.dart b/dev/manual_tests/lib/overlay_geometry.dart
index 54f68c7667d..a223fa44e70 100644
--- a/dev/manual_tests/lib/overlay_geometry.dart
+++ b/dev/manual_tests/lib/overlay_geometry.dart
@@ -159,7 +159,7 @@ class OverlayGeometryAppState extends State<OverlayGeometryApp> {
       setState(() {
         final double dy = markersScrollOffset - notification.metrics.extentBefore;
         markersScrollOffset = notification.metrics.extentBefore;
-        for (MarkerType type in markers.keys) {
+        for (final MarkerType type in markers.keys) {
           final Offset oldPosition = markers[type];
           markers[type] = oldPosition.translate(0.0, dy);
         }
@@ -199,7 +199,7 @@ class OverlayGeometryAppState extends State<OverlayGeometryApp> {
             ),
           ),
         ),
-        for (MarkerType type in markers.keys)
+        for (final MarkerType type in markers.keys)
           Marker(type: type, position: markers[type]),
       ],
     );
diff --git a/dev/manual_tests/lib/raw_keyboard.dart b/dev/manual_tests/lib/raw_keyboard.dart
index fabcb627733..5f78ca378b5 100644
--- a/dev/manual_tests/lib/raw_keyboard.dart
+++ b/dev/manual_tests/lib/raw_keyboard.dart
@@ -127,8 +127,8 @@ class _HardwareKeyDemoState extends State<RawKeyboardDemo> {
           if (_event.character != null) {
             dataText.add(Text('character: ${_event.character}'));
           }
-          for (ModifierKey modifier in data.modifiersPressed.keys) {
-            for (KeyboardSide side in KeyboardSide.values) {
+          for (final ModifierKey modifier in data.modifiersPressed.keys) {
+            for (final KeyboardSide side in KeyboardSide.values) {
               if (data.isModifierPressed(modifier, side: side)) {
                 dataText.add(
                   Text('${_getEnumName(side)} ${_getEnumName(modifier).replaceAll('Modifier', '')} pressed'),
diff --git a/dev/manual_tests/lib/text.dart b/dev/manual_tests/lib/text.dart
index 37b421c6d0f..3ca82aca286 100644
--- a/dev/manual_tests/lib/text.dart
+++ b/dev/manual_tests/lib/text.dart
@@ -343,7 +343,7 @@ class _FuzzerState extends State<Fuzzer> with SingleTickerProviderStateMixin {
     if (node.children == null || node.children.isEmpty)
       return 0;
     int result = 0;
-    for (TextSpan child in node.children.cast<TextSpan>())
+    for (final TextSpan child in node.children.cast<TextSpan>())
       result = math.max(result, depthOf(child));
     return result;
   }
@@ -582,7 +582,7 @@ class _UnderlinesState extends State<Underlines> {
                 child: ListBody(
                   children: <Widget>[
                     _wrap(null),
-                    for (TextDecorationStyle style in TextDecorationStyle.values) _wrap(style),
+                    for (final TextDecorationStyle style in TextDecorationStyle.values) _wrap(style),
                   ],
                 ),
               ),
@@ -675,7 +675,7 @@ class _FallbackState extends State<Fallback> {
                   child: IntrinsicWidth(
                     child: ListBody(
                       children: <Widget>[
-                        for (String font in androidFonts)
+                        for (final String font in androidFonts)
                           Text(
                             multiScript,
                             style: style.copyWith(
diff --git a/dev/snippets/lib/snippets.dart b/dev/snippets/lib/snippets.dart
index 3e955b08fbc..b21c795c36b 100644
--- a/dev/snippets/lib/snippets.dart
+++ b/dev/snippets/lib/snippets.dart
@@ -104,7 +104,7 @@ class SnippetGenerator {
     final List<String> result = <String>[];
     const HtmlEscape htmlEscape = HtmlEscape();
     String language;
-    for (_ComponentTuple injection in injections) {
+    for (final _ComponentTuple injection in injections) {
       if (!injection.name.startsWith('code')) {
         continue;
       }
@@ -152,7 +152,7 @@ class SnippetGenerator {
     final List<_ComponentTuple> components = <_ComponentTuple>[];
     String language;
     final RegExp codeStartEnd = RegExp(r'^\s*```([-\w]+|[-\w]+ ([-\w]+))?\s*$');
-    for (String line in input.split('\n')) {
+    for (final String line in input.split('\n')) {
       final Match match = codeStartEnd.firstMatch(line);
       if (match != null) { // If we saw the start or end of a code block
         inCodeBlock = !inCodeBlock;
@@ -188,7 +188,7 @@ class SnippetGenerator {
   String _addLineNumbers(String app) {
     final StringBuffer buffer = StringBuffer();
     int count = 0;
-    for (String line in app.split('\n')) {
+    for (final String line in app.split('\n')) {
       count++;
       buffer.writeln('${count.toString().padLeft(5, ' ')}: $line');
     }
diff --git a/dev/tools/dartdoc.dart b/dev/tools/dartdoc.dart
index 103697e248f..7c3a436331e 100644
--- a/dev/tools/dartdoc.dart
+++ b/dev/tools/dartdoc.dart
@@ -57,7 +57,7 @@ Future<void> main(List<String> arguments) async {
   // https://github.com/dart-lang/dartdoc/issues/1982
   buf.writeln('version: 0.0.0');
   buf.writeln('dependencies:');
-  for (String package in findPackageNames()) {
+  for (final String package in findPackageNames()) {
     buf.writeln('  $package:');
     buf.writeln('    sdk: flutter');
   }
@@ -72,7 +72,7 @@ Future<void> main(List<String> arguments) async {
   libDir.createSync();
 
   final StringBuffer contents = StringBuffer('library temp_doc;\n\n');
-  for (String libraryRef in libraryRefs()) {
+  for (final String libraryRef in libraryRefs()) {
     contents.writeln('import \'package:$libraryRef\';');
   }
   File('$kDocsRoot/lib/temp_doc.dart').writeAsStringSync(contents.toString());
@@ -313,7 +313,7 @@ void copyDirectorySync(Directory srcDir, Directory destDir, [void onFileCopied(F
   if (!destDir.existsSync())
     destDir.createSync(recursive: true);
 
-  for (FileSystemEntity entity in srcDir.listSync()) {
+  for (final FileSystemEntity entity in srcDir.listSync()) {
     final String newPath = path.join(destDir.path, path.basename(entity.path));
     if (entity is File) {
       final File newFile = File(newPath);
@@ -361,7 +361,7 @@ void sanityCheckDocs() {
     '$kPublishRoot/api/material/Tooltip-class.html',
     '$kPublishRoot/api/widgets/Widget-class.html',
   ];
-  for (String canary in canaries) {
+  for (final String canary in canaries) {
     if (!File(canary).existsSync())
       throw Exception('Missing "$canary", which probably means the documentation failed to build correctly.');
   }
@@ -470,9 +470,9 @@ List<Directory> findPackages() {
 
 /// Returns import or on-disk paths for all libraries in the Flutter SDK.
 Iterable<String> libraryRefs() sync* {
-  for (Directory dir in findPackages()) {
+  for (final Directory dir in findPackages()) {
     final String dirName = path.basename(dir.path);
-    for (FileSystemEntity file in Directory('${dir.path}/lib').listSync()) {
+    for (final FileSystemEntity file in Directory('${dir.path}/lib').listSync()) {
       if (file is File && file.path.endsWith('.dart')) {
         yield '$dirName/${path.basename(file.path)}';
       }
diff --git a/dev/tools/gen_keycodes/lib/code_gen.dart b/dev/tools/gen_keycodes/lib/code_gen.dart
index 8d7d2d25c4d..c7f006a18f8 100644
--- a/dev/tools/gen_keycodes/lib/code_gen.dart
+++ b/dev/tools/gen_keycodes/lib/code_gen.dart
@@ -20,7 +20,7 @@ class CodeGenerator {
     final StringBuffer result = StringBuffer();
     final List<String> words = input.split(RegExp(r'\s+'));
     String currentLine = words.removeAt(0);
-    for (String word in words) {
+    for (final String word in words) {
       if ((currentLine.length + word.length) < wrapWidth) {
         currentLine += ' $word';
       } else {
@@ -37,7 +37,7 @@ class CodeGenerator {
   /// Gets the generated definitions of PhysicalKeyboardKeys.
   String get physicalDefinitions {
     final StringBuffer definitions = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       final String firstComment = wrapString('Represents the location of the '
         '"${entry.commentName}" key on a generalized keyboard.');
       final String otherComments = wrapString('See the function '
@@ -73,7 +73,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
       }
     }
 
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       printKey(
         entry.flutterId,
         entry.keyLabel,
@@ -81,7 +81,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
         entry.commentName,
       );
     }
-    for (String name in Key.synonyms.keys) {
+    for (final String name in Key.synonyms.keys) {
       // Use the first item in the synonyms as a template for the ID to use.
       // It won't end up being the same value because it'll be in the pseudo-key
       // plane.
@@ -99,8 +99,8 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
 
   String get logicalSynonyms {
     final StringBuffer synonyms = StringBuffer();
-    for (String name in Key.synonyms.keys) {
-      for (String synonym in Key.synonyms[name].cast<String>()) {
+    for (final String name in Key.synonyms.keys) {
+      for (final String synonym in Key.synonyms[name].cast<String>()) {
         final String keyName = upperCamelToLowerCamel(synonym);
         synonyms.writeln('    $keyName: $name,');
       }
@@ -124,7 +124,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of USB HID codes to physical keys.
   String get predefinedHidCodeMap {
     final StringBuffer scanCodeMap = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       scanCodeMap.writeln('    ${toHex(entry.usbHidCode)}: ${entry.constantName},');
     }
     return scanCodeMap.toString().trimRight();
@@ -133,10 +133,10 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// THis generates the map of Flutter key codes to logical keys.
   String get predefinedKeyCodeMap {
     final StringBuffer keyCodeMap = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       keyCodeMap.writeln('    ${toHex(entry.flutterId, digits: 10)}: ${entry.constantName},');
     }
-    for (String entry in Key.synonyms.keys) {
+    for (final String entry in Key.synonyms.keys) {
       // Use the first item in the synonyms as a template for the ID to use.
       // It won't end up being the same value because it'll be in the pseudo-key
       // plane.
@@ -152,9 +152,9 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of GLFW number pad key codes to logical keys.
   String get glfwNumpadMap {
     final StringBuffer glfwNumpadMap = StringBuffer();
-    for (Key entry in numpadKeyData) {
+    for (final Key entry in numpadKeyData) {
       if (entry.glfwKeyCodes != null) {
-        for (int code in entry.glfwKeyCodes.cast<int>()) {
+        for (final int code in entry.glfwKeyCodes.cast<int>()) {
           glfwNumpadMap.writeln('  $code: LogicalKeyboardKey.${entry.constantName},');
         }
       }
@@ -165,9 +165,9 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of GLFW key codes to logical keys.
   String get glfwKeyCodeMap {
     final StringBuffer glfwKeyCodeMap = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       if (entry.glfwKeyCodes != null) {
-        for (int code in entry.glfwKeyCodes.cast<int>()) {
+        for (final int code in entry.glfwKeyCodes.cast<int>()) {
           glfwKeyCodeMap.writeln('  $code: LogicalKeyboardKey.${entry.constantName},');
         }
       }
@@ -178,7 +178,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of XKB USB HID codes to physical keys.
   String get xkbScanCodeMap {
     final StringBuffer xkbScanCodeMap = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       if (entry.xKbScanCode != null) {
         xkbScanCodeMap.writeln('  ${toHex(entry.xKbScanCode)}: PhysicalKeyboardKey.${entry.constantName},');
       }
@@ -189,9 +189,9 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of Android key codes to logical keys.
   String get androidKeyCodeMap {
     final StringBuffer androidKeyCodeMap = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       if (entry.androidKeyCodes != null) {
-        for (int code in entry.androidKeyCodes.cast<int>()) {
+        for (final int code in entry.androidKeyCodes.cast<int>()) {
           androidKeyCodeMap.writeln('  $code: LogicalKeyboardKey.${entry.constantName},');
         }
       }
@@ -202,9 +202,9 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of Android number pad key codes to logical keys.
   String get androidNumpadMap {
     final StringBuffer androidKeyCodeMap = StringBuffer();
-    for (Key entry in numpadKeyData) {
+    for (final Key entry in numpadKeyData) {
       if (entry.androidKeyCodes != null) {
-        for (int code in entry.androidKeyCodes.cast<int>()) {
+        for (final int code in entry.androidKeyCodes.cast<int>()) {
           androidKeyCodeMap.writeln('  $code: LogicalKeyboardKey.${entry.constantName},');
         }
       }
@@ -215,9 +215,9 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of Android scan codes to physical keys.
   String get androidScanCodeMap {
     final StringBuffer androidScanCodeMap = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       if (entry.androidScanCodes != null) {
-        for (int code in entry.androidScanCodes.cast<int>()) {
+        for (final int code in entry.androidScanCodes.cast<int>()) {
           androidScanCodeMap.writeln('  $code: PhysicalKeyboardKey.${entry.constantName},');
         }
       }
@@ -228,7 +228,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of macOS key codes to physical keys.
   String get macOsScanCodeMap {
     final StringBuffer macOsScanCodeMap = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       if (entry.macOsScanCode != null) {
         macOsScanCodeMap.writeln('  ${toHex(entry.macOsScanCode)}: PhysicalKeyboardKey.${entry.constantName},');
       }
@@ -239,7 +239,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of macOS number pad key codes to logical keys.
   String get macOsNumpadMap {
     final StringBuffer macOsNumPadMap = StringBuffer();
-    for (Key entry in numpadKeyData) {
+    for (final Key entry in numpadKeyData) {
       if (entry.macOsScanCode != null) {
         macOsNumPadMap.writeln('  ${toHex(entry.macOsScanCode)}: LogicalKeyboardKey.${entry.constantName},');
       }
@@ -249,7 +249,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
 
   String get macOsFunctionKeyMap {
     final StringBuffer macOsFunctionKeyMap = StringBuffer();
-    for (Key entry in functionKeyData) {
+    for (final Key entry in functionKeyData) {
       if (entry.macOsScanCode != null) {
         macOsFunctionKeyMap.writeln('  ${toHex(entry.macOsScanCode)}: LogicalKeyboardKey.${entry.constantName},');
       }
@@ -260,7 +260,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of Fuchsia key codes to logical keys.
   String get fuchsiaKeyCodeMap {
     final StringBuffer fuchsiaKeyCodeMap = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       if (entry.usbHidCode != null) {
         fuchsiaKeyCodeMap.writeln('  ${toHex(entry.flutterId)}: LogicalKeyboardKey.${entry.constantName},');
       }
@@ -271,7 +271,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of Fuchsia USB HID codes to physical keys.
   String get fuchsiaHidCodeMap {
     final StringBuffer fuchsiaScanCodeMap = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       if (entry.usbHidCode != null) {
         fuchsiaScanCodeMap.writeln('  ${toHex(entry.usbHidCode)}: PhysicalKeyboardKey.${entry.constantName},');
       }
@@ -282,7 +282,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of Web KeyboardEvent codes to logical keys.
   String get webLogicalKeyMap {
     final StringBuffer result = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       if (entry.name != null) {
         result.writeln("  '${entry.name}': LogicalKeyboardKey.${entry.constantName},");
       }
@@ -293,7 +293,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of Web KeyboardEvent codes to physical keys.
   String get webPhysicalKeyMap {
     final StringBuffer result = StringBuffer();
-    for (Key entry in keyData.data) {
+    for (final Key entry in keyData.data) {
       if (entry.name != null) {
         result.writeln("  '${entry.name}': PhysicalKeyboardKey.${entry.constantName},");
       }
@@ -304,7 +304,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
   /// This generates the map of Web number pad codes to logical keys.
   String get webNumpadMap {
     final StringBuffer result = StringBuffer();
-    for (Key entry in numpadKeyData) {
+    for (final Key entry in numpadKeyData) {
       if (entry.name != null) {
         result.writeln("  '${entry.name}': LogicalKeyboardKey.${entry.constantName},");
       }
@@ -359,7 +359,7 @@ $otherComments  static const LogicalKeyboardKey $constantName = LogicalKeyboardK
 
   static String _injectDictionary(String template, Map<String, String> dictionary) {
     String result = template;
-    for (String key in dictionary.keys) {
+    for (final String key in dictionary.keys) {
       result = result.replaceAll('@@@$key@@@', dictionary[key]);
     }
     return result;
diff --git a/dev/tools/gen_keycodes/lib/key_data.dart b/dev/tools/gen_keycodes/lib/key_data.dart
index 9c755a081b7..8853f73acca 100644
--- a/dev/tools/gen_keycodes/lib/key_data.dart
+++ b/dev/tools/gen_keycodes/lib/key_data.dart
@@ -53,18 +53,18 @@ class KeyData {
   /// Parses the given JSON data and populates the data structure from it.
   KeyData.fromJson(Map<String, dynamic> contentMap) {
     data = <Key>[
-      for (String key in contentMap.keys) Key.fromJsonMapEntry(key, contentMap[key] as Map<String, List<dynamic>>),
+      for (final String key in contentMap.keys) Key.fromJsonMapEntry(key, contentMap[key] as Map<String, List<dynamic>>),
     ];
   }
 
   /// Converts the data structure into a JSON structure that can be parsed by
   /// [KeyData.fromJson].
   Map<String, dynamic> toJson() {
-    for (Key entry in data) {
+    for (final Key entry in data) {
       // Android Key names
       entry.androidKeyNames = _nameToAndroidName[entry.constantName]?.cast<String>();
       if (entry.androidKeyNames != null && entry.androidKeyNames.isNotEmpty) {
-        for (String androidKeyName in entry.androidKeyNames) {
+        for (final String androidKeyName in entry.androidKeyNames) {
           if (_nameToAndroidKeyCode[androidKeyName] != null) {
             entry.androidKeyCodes ??= <int>[];
             entry.androidKeyCodes.add(_nameToAndroidKeyCode[androidKeyName]);
@@ -79,7 +79,7 @@ class KeyData {
       // GLFW key names
       entry.glfwKeyNames = _nameToGlfwName[entry.constantName]?.cast<String>();
       if (entry.glfwKeyNames != null && entry.glfwKeyNames.isNotEmpty) {
-        for (String glfwKeyName in entry.glfwKeyNames) {
+        for (final String glfwKeyName in entry.glfwKeyNames) {
           if (_nameToGlfwKeyCode[glfwKeyName] != null) {
             entry.glfwKeyCodes ??= <int>[];
             entry.glfwKeyCodes.add(_nameToGlfwKeyCode[glfwKeyName]);
@@ -89,7 +89,7 @@ class KeyData {
     }
 
     final Map<String, dynamic> outputMap = <String, dynamic>{};
-    for (Key entry in data) {
+    for (final Key entry in data) {
       outputMap[entry.constantName] = entry.toJson();
     }
     return outputMap;
@@ -178,7 +178,7 @@ class KeyData {
     headerFile = headerFile.replaceAllMapped(enumBlock, (Match match) => match.group(1));
     final RegExp enumEntry = RegExp(r'''AKEYCODE_([A-Z0-9_]+)\s*=\s*([0-9]+),?''');
     final Map<String, int> result = <String, int>{};
-    for (Match match in enumEntry.allMatches(headerFile)) {
+    for (final Match match in enumEntry.allMatches(headerFile)) {
       result[match.group(1)] = int.parse(match.group(2));
     }
     return result;
@@ -193,7 +193,7 @@ class KeyData {
     // Only get the KEY definitions, ignore the rest (mouse, joystick, etc).
     final RegExp enumEntry = RegExp(r'''define GLFW_KEY_([A-Z0-9_]+)\s*([A-Z0-9_]+),?''');
     final Map<String, dynamic> replaced = <String, dynamic>{};
-    for (Match match in enumEntry.allMatches(headerFile)) {
+    for (final Match match in enumEntry.allMatches(headerFile)) {
       replaced[match.group(1)] = int.tryParse(match.group(2)) ?? match.group(2).replaceAll('GLFW_KEY_', '');
     }
     final Map<String, int> result = <String, int>{};
diff --git a/dev/tools/java_and_objc_doc.dart b/dev/tools/java_and_objc_doc.dart
index 7f41dffeeea..2a0f8367856 100644
--- a/dev/tools/java_and_objc_doc.dart
+++ b/dev/tools/java_and_objc_doc.dart
@@ -56,7 +56,7 @@ Future<void> generateDocs(String url, String docName, String checkFile) async {
   print('Extracting $docName to ${output.path}');
   output.createSync(recursive: true);
 
-  for (ArchiveFile af in archive) {
+  for (final ArchiveFile af in archive) {
     if (!af.name.endsWith('/')) {
       final File file = File('${output.path}/${af.name}');
       file.createSync(recursive: true);
diff --git a/dev/tools/localization/bin/encode_kn_arb_files.dart b/dev/tools/localization/bin/encode_kn_arb_files.dart
index 805b9b3cd82..6477a5de990 100644
--- a/dev/tools/localization/bin/encode_kn_arb_files.dart
+++ b/dev/tools/localization/bin/encode_kn_arb_files.dart
@@ -36,7 +36,7 @@ Map<String, dynamic> loadBundle(File file) {
 }
 
 void encodeBundleTranslations(Map<String, dynamic> bundle) {
-  for (String key in bundle.keys) {
+  for (final String key in bundle.keys) {
     // The ARB file resource "attributes" for foo are called @foo. Don't need
     // to encode them.
     if (key.startsWith('@'))
@@ -54,7 +54,7 @@ void encodeBundleTranslations(Map<String, dynamic> bundle) {
 void checkEncodedTranslations(Map<String, dynamic> encodedBundle, Map<String, dynamic> bundle) {
   bool errorFound = false;
   const JsonDecoder decoder = JsonDecoder();
-  for (String key in bundle.keys) {
+  for (final String key in bundle.keys) {
     if (decoder.convert('"${encodedBundle[key]}"') != bundle[key]) {
       stderr.writeln('  encodedTranslation for $key does not match original value "${bundle[key]}"');
       errorFound = true;
@@ -67,7 +67,7 @@ void checkEncodedTranslations(Map<String, dynamic> encodedBundle, Map<String, dy
 void rewriteBundle(File file, Map<String, dynamic> bundle) {
   final StringBuffer contents = StringBuffer();
   contents.writeln('{');
-  for (String key in bundle.keys) {
+  for (final String key in bundle.keys) {
     contents.writeln('  "$key": "${bundle[key]}"${key == bundle.keys.last ? '' : ','}');
   }
   contents.writeln('}');
diff --git a/dev/tools/localization/bin/gen_date_localizations.dart b/dev/tools/localization/bin/gen_date_localizations.dart
index b9c5f725f08..5c805093fc1 100644
--- a/dev/tools/localization/bin/gen_date_localizations.dart
+++ b/dev/tools/localization/bin/gen_date_localizations.dart
@@ -167,7 +167,7 @@ Set<String> _supportedLocales() {
   final Set<String> supportedLocales = <String>{};
   final RegExp filenameRE = RegExp(r'(?:material|cupertino)_(\w+)\.arb$');
   final Directory supportedLocalesDirectory = Directory(path.join('packages', 'flutter_localizations', 'lib', 'src', 'l10n'));
-  for (FileSystemEntity entity in supportedLocalesDirectory.listSync()) {
+  for (final FileSystemEntity entity in supportedLocalesDirectory.listSync()) {
     final String filePath = entity.path;
     if (FileSystemEntity.isFileSync(filePath) && filenameRE.hasMatch(filePath))
       supportedLocales.add(filenameRE.firstMatch(filePath)[1]);
@@ -181,7 +181,7 @@ Map<String, File> _listIntlData(Directory directory) {
     .listSync()
     .whereType<File>()
     .where((File file) => file.path.endsWith('.json'));
-  for (File file in files) {
+  for (final File file in files) {
     final String locale = path.basenameWithoutExtension(file.path);
     localeFiles[locale] = file;
   }
diff --git a/dev/tools/localization/bin/gen_localizations.dart b/dev/tools/localization/bin/gen_localizations.dart
index 5b84a4a63cc..70f343c0379 100644
--- a/dev/tools/localization/bin/gen_localizations.dart
+++ b/dev/tools/localization/bin/gen_localizations.dart
@@ -87,7 +87,7 @@ String generateArbBasedLocalizationSubclasses({
   // Used to calculate if there are any corresponding countries for a given language and script.
   final Map<LocaleInfo, Set<String>> languageAndScriptToCountryCodes = <LocaleInfo, Set<String>>{};
   final Set<String> allResourceIdentifiers = <String>{};
-  for (LocaleInfo locale in localeToResources.keys.toList()..sort()) {
+  for (final LocaleInfo locale in localeToResources.keys.toList()..sort()) {
     if (locale.scriptCode != null) {
       languageToScriptCodes[locale.languageCode] ??= <String>{};
       languageToScriptCodes[locale.languageCode].add(locale.scriptCode);
@@ -129,13 +129,13 @@ String generateArbBasedLocalizationSubclasses({
   final List<String> allKeys = allResourceIdentifiers.toList()..sort();
   final List<String> languageCodes = languageToLocales.keys.toList()..sort();
   final LocaleInfo canonicalLocale = LocaleInfo.fromString('en');
-  for (String languageName in languageCodes) {
+  for (final String languageName in languageCodes) {
     final LocaleInfo languageLocale = LocaleInfo.fromString(languageName);
     output.writeln(generateClassDeclaration(languageLocale, generatedClassPrefix, baseClass));
     output.writeln(generateConstructor(languageLocale));
 
     final Map<String, String> languageResources = localeToResources[languageLocale];
-    for (String key in allKeys) {
+    for (final String key in allKeys) {
       final Map<String, dynamic> attributes = localeToResourceAttributes[canonicalLocale][key] as Map<String, dynamic>;
       output.writeln(generateGetter(key, languageResources[key], attributes, languageLocale));
     }
@@ -146,7 +146,7 @@ String generateArbBasedLocalizationSubclasses({
       scriptCodeCount = languageToScriptCodes[languageName].length;
       // Language has scriptCodes, so we need to properly fallback countries to corresponding
       // script default values before language default values.
-      for (String scriptCode in languageToScriptCodes[languageName]) {
+      for (final String scriptCode in languageToScriptCodes[languageName]) {
         final LocaleInfo scriptBaseLocale = LocaleInfo.fromString(languageName + '_' + scriptCode);
         output.writeln(generateClassDeclaration(
           scriptBaseLocale,
@@ -155,7 +155,7 @@ String generateArbBasedLocalizationSubclasses({
         ));
         output.writeln(generateConstructor(scriptBaseLocale));
         final Map<String, String> scriptResources = localeToResources[scriptBaseLocale];
-        for (String key in scriptResources.keys.toList()..sort()) {
+        for (final String key in scriptResources.keys.toList()..sort()) {
           if (languageResources[key] == scriptResources[key])
             continue;
           final Map<String, dynamic> attributes = localeToResourceAttributes[canonicalLocale][key] as Map<String, dynamic>;
@@ -164,7 +164,7 @@ String generateArbBasedLocalizationSubclasses({
         output.writeln('}');
 
         final List<LocaleInfo> localeCodes = languageToLocales[languageName]..sort();
-        for (LocaleInfo locale in localeCodes) {
+        for (final LocaleInfo locale in localeCodes) {
           if (locale.originalString == languageName)
             continue;
           if (locale.originalString == languageName + '_' + scriptCode)
@@ -179,7 +179,7 @@ String generateArbBasedLocalizationSubclasses({
           ));
           output.writeln(generateConstructor(locale));
           final Map<String, String> localeResources = localeToResources[locale];
-          for (String key in localeResources.keys) {
+          for (final String key in localeResources.keys) {
             // When script fallback contains the key, we compare to it instead of language fallback.
             if (scriptResources.containsKey(key) ? scriptResources[key] == localeResources[key] : languageResources[key] == localeResources[key])
               continue;
@@ -193,7 +193,7 @@ String generateArbBasedLocalizationSubclasses({
       // No scriptCode. Here, we do not compare against script default (because it
       // doesn't exist).
       final List<LocaleInfo> localeCodes = languageToLocales[languageName]..sort();
-      for (LocaleInfo locale in localeCodes) {
+      for (final LocaleInfo locale in localeCodes) {
         if (locale.originalString == languageName)
           continue;
         countryCodeCount += 1;
@@ -204,7 +204,7 @@ String generateArbBasedLocalizationSubclasses({
           '$generatedClassPrefix${camelCase(languageLocale)}',
         ));
         output.writeln(generateConstructor(locale));
-        for (String key in localeResources.keys) {
+        for (final String key in localeResources.keys) {
           if (languageResources[key] == localeResources[key])
             continue;
           final Map<String, dynamic> attributes = localeToResourceAttributes[canonicalLocale][key] as Map<String, dynamic>;
@@ -262,7 +262,7 @@ $supportedLocales/// {@endtemplate}
 /// [$baseClass.delegate].
 $factoryDeclaration
   switch (locale.languageCode) {''');
-  for (String language in languageToLocales.keys) {
+  for (final String language in languageToLocales.keys) {
     // Only one instance of the language.
     if (languageToLocales[language].length == 1) {
       output.writeln('''
@@ -272,7 +272,7 @@ $factoryDeclaration
       output.writeln('''
     case '$language': {
       switch (locale.countryCode) {''');
-      for (LocaleInfo locale in languageToLocales[language]) {
+      for (final LocaleInfo locale in languageToLocales[language]) {
         if (locale.originalString == language)
           continue;
         assert(locale.length > 1);
@@ -290,14 +290,14 @@ $factoryDeclaration
       output.writeln('''
     case '$language': {
       switch (locale.scriptCode) {''');
-      for (String scriptCode in languageToScriptCodes[language]) {
+      for (final String scriptCode in languageToScriptCodes[language]) {
         final LocaleInfo scriptLocale = LocaleInfo.fromString(language + '_' + scriptCode);
         output.writeln('''
         case '$scriptCode': {''');
         if (languageAndScriptToCountryCodes.containsKey(scriptLocale)) {
           output.writeln('''
           switch (locale.countryCode) {''');
-          for (LocaleInfo locale in languageToLocales[language]) {
+          for (final LocaleInfo locale in languageToLocales[language]) {
             if (locale.countryCode == null)
               continue;
             else
@@ -326,7 +326,7 @@ $factoryDeclaration
         } else {
           // Not Explicitly defined, fallback to first locale with the same language and
           // script:
-          for (LocaleInfo locale in languageToLocales[language]) {
+          for (final LocaleInfo locale in languageToLocales[language]) {
             if (locale.scriptCode != scriptCode)
               continue;
             if (languageAndScriptToCountryCodes.containsKey(scriptLocale)) {
@@ -345,7 +345,7 @@ $factoryDeclaration
       if (hasCountryCode) {
       output.writeln('''
       switch (locale.countryCode) {''');
-        for (LocaleInfo locale in languageToLocales[language]) {
+        for (final LocaleInfo locale in languageToLocales[language]) {
           if (locale.originalString == language)
             continue;
           assert(locale.length > 1);
diff --git a/dev/tools/localization/gen_l10n.dart b/dev/tools/localization/gen_l10n.dart
index 5281c44c632..c3dad4e1113 100644
--- a/dev/tools/localization/gen_l10n.dart
+++ b/dev/tools/localization/gen_l10n.dart
@@ -270,7 +270,7 @@ String generateDateFormattingLogic(Map<String, dynamic> bundle, String key) {
   final Map<String, dynamic> attributesMap = bundle['@$key'] as Map<String, dynamic>;
   if (attributesMap != null && attributesMap.containsKey('placeholders')) {
     final Map<String, dynamic> placeholders = attributesMap['placeholders'] as Map<String, dynamic>;
-    for (String placeholder in placeholders.keys) {
+    for (final String placeholder in placeholders.keys) {
       final dynamic value = placeholders[placeholder];
       if (
         value is Map<String, dynamic> &&
@@ -302,7 +302,7 @@ List<String> genIntlMethodArgs(Map<String, dynamic> bundle, String key) {
       final Map<String, dynamic> placeholders = attributesMap['placeholders'] as Map<String, dynamic>;
       if (placeholders.isNotEmpty) {
         final List<String> argumentList = <String>[];
-        for (String placeholder in placeholders.keys) {
+        for (final String placeholder in placeholders.keys) {
           final dynamic value = placeholders[placeholder];
           if (
             value is Map<String, dynamic> &&
@@ -328,7 +328,7 @@ String genSimpleMethod(Map<String, dynamic> bundle, String key) {
     String message = bundle[key] as String;
     final Map<String, dynamic> attributesMap = bundle['@$key'] as Map<String, dynamic>;
     final Map<String, dynamic> placeholders = attributesMap['placeholders'] as Map<String, dynamic>;
-    for (String placeholder in placeholders.keys) {
+    for (final String placeholder in placeholders.keys) {
       final dynamic value = placeholders[placeholder];
       if (value is Map<String, dynamic> && _isDateParameter(value)) {
         message = message.replaceAll('{$placeholder}', '\$${placeholder}String');
@@ -388,7 +388,7 @@ String genPluralMethod(Map<String, dynamic> arbBundle, String resourceId) {
   // To make it easier to parse the plurals message, temporarily replace each
   // "{placeholder}" parameter with "#placeholder#".
   String message = arbBundle[resourceId] as String;
-  for (String placeholder in placeholders)
+  for (final String placeholder in placeholders)
     message = message.replaceAll('{$placeholder}', '#$placeholder#');
 
   final Map<String, String> pluralIds = <String, String>{
@@ -406,12 +406,12 @@ String genPluralMethod(Map<String, dynamic> arbBundle, String resourceId) {
     ...genIntlMethodArgs(arbBundle, resourceId),
   ];
 
-  for (String pluralKey in pluralIds.keys) {
+  for (final String pluralKey in pluralIds.keys) {
     final RegExp expRE = RegExp('($pluralKey){([^}]+)}');
     final RegExpMatch match = expRE.firstMatch(message);
     if (match != null && match.groupCount == 2) {
       String argValue = match.group(2);
-      for (String placeholder in placeholders) {
+      for (final String placeholder in placeholders) {
         final dynamic value = placeholdersMap[placeholder];
         if (value is Map<String, dynamic> && _isDateParameter(value)) {
           argValue = argValue.replaceAll('#$placeholder#', '\$${placeholder}String');
@@ -435,7 +435,7 @@ String genSupportedLocaleProperty(Set<LocaleInfo> supportedLocales) {
   const String suffix = '),\n  ];';
 
   String resultingProperty = prefix;
-  for (LocaleInfo locale in supportedLocales) {
+  for (final LocaleInfo locale in supportedLocales) {
     final String languageCode = locale.languageCode;
     final String countryCode = locale.countryCode;
 
@@ -668,7 +668,7 @@ class LocalizationsGenerator {
       .toList();
     final List<LocaleInfo> localeInfoList = <LocaleInfo>[];
 
-    for (File file in fileSystemEntityList) {
+    for (final File file in fileSystemEntityList) {
       final String filePath = file.path;
       if (arbFilenameRE.hasMatch(filePath)) {
         final Map<String, dynamic> arbContents = json.decode(file.readAsStringSync()) as Map<String, dynamic>;
@@ -705,7 +705,7 @@ class LocalizationsGenerator {
     }));
 
     if (preferredSupportedLocales != null) {
-      for (LocaleInfo preferredLocale in preferredSupportedLocales) {
+      for (final LocaleInfo preferredLocale in preferredSupportedLocales) {
         if (!localeInfoList.contains(preferredLocale)) {
           throw L10nException(
             'The preferred supported locale, \'$preferredLocale\', cannot be '
@@ -750,7 +750,7 @@ class LocalizationsGenerator {
     }
 
     final List<String> sortedArbKeys = bundle.keys.toList()..sort();
-    for (String key in sortedArbKeys) {
+    for (final String key in sortedArbKeys) {
       if (key.startsWith('@'))
         continue;
       if (!_isValidGetterAndMethodName(key))
diff --git a/dev/tools/localization/localizations_utils.dart b/dev/tools/localization/localizations_utils.dart
index 61d830d620a..9813d4334e7 100644
--- a/dev/tools/localization/localizations_utils.dart
+++ b/dev/tools/localization/localizations_utils.dart
@@ -155,7 +155,7 @@ void loadMatchingArbsIntoBundleMaps({
   /// overwrite the existing assumed data.
   final Set<LocaleInfo> assumedLocales = <LocaleInfo>{};
 
-  for (FileSystemEntity entity in directory.listSync().toList()..sort(sortFilesByPath)) {
+  for (final FileSystemEntity entity in directory.listSync().toList()..sort(sortFilesByPath)) {
     final String entityPath = entity.path;
     if (FileSystemEntity.isFileSync(entityPath) && filenamePattern.hasMatch(entityPath)) {
       final String localeString = filenamePattern.firstMatch(entityPath)[1];
@@ -166,7 +166,7 @@ void loadMatchingArbsIntoBundleMaps({
         final Map<String, String> resources = localeToResources[locale];
         final Map<String, dynamic> attributes = localeToResourceAttributes[locale];
         final Map<String, dynamic> bundle = json.decode(file.readAsStringSync()) as Map<String, dynamic>;
-        for (String key in bundle.keys) {
+        for (final String key in bundle.keys) {
           // The ARB file resource "attributes" for foo are called @foo.
           if (key.startsWith('@'))
             attributes[key.substring(1)] = bundle[key];
@@ -270,7 +270,7 @@ const String registry = 'https://www.iana.org/assignments/language-subtag-regist
 Map<String, List<String>> _parseSection(String section) {
   final Map<String, List<String>> result = <String, List<String>>{};
   List<String> lastHeading;
-  for (String line in section.split('\n')) {
+  for (final String line in section.split('\n')) {
     if (line == '')
       continue;
     if (line.startsWith('  ')) {
@@ -304,7 +304,7 @@ Future<void> precacheLanguageAndRegionTags() async {
   final String body = (await response.cast<List<int>>().transform<String>(utf8.decoder).toList()).join('');
   client.close(force: true);
   final List<Map<String, List<String>>> sections = body.split('%%').skip(1).map<Map<String, List<String>>>(_parseSection).toList();
-  for (Map<String, List<String>> section in sections) {
+  for (final Map<String, List<String>> section in sections) {
     assert(section.containsKey('Type'), section.toString());
     final String type = section['Type'].single;
     if (type == 'language' || type == 'region' || type == 'script') {
diff --git a/dev/tools/localization/localizations_validator.dart b/dev/tools/localization/localizations_validator.dart
index 17cd9c88cee..e6f45600570 100644
--- a/dev/tools/localization/localizations_validator.dart
+++ b/dev/tools/localization/localizations_validator.dart
@@ -38,7 +38,7 @@ void validateEnglishLocalizations(File file) {
 
   final Map<String, dynamic> bundle = json.decode(file.readAsStringSync()) as Map<String, dynamic>;
 
-  for (String resourceId in bundle.keys) {
+  for (final String resourceId in bundle.keys) {
     if (resourceId.startsWith('@'))
       continue;
 
@@ -55,7 +55,7 @@ void validateEnglishLocalizations(File file) {
     errorMessages.writeln('A value was not specified for @$resourceId');
   }
 
-  for (String atResourceId in bundle.keys) {
+  for (final String atResourceId in bundle.keys) {
     if (!atResourceId.startsWith('@'))
       continue;
 
diff --git a/dev/tools/mega_gallery.dart b/dev/tools/mega_gallery.dart
index 7dcaa669cb5..c7cd9e730bd 100644
--- a/dev/tools/mega_gallery.dart
+++ b/dev/tools/mega_gallery.dart
@@ -134,7 +134,7 @@ void _copy(Directory source, Directory target) {
   if (!target.existsSync())
     target.createSync(recursive: true);
 
-  for (FileSystemEntity entity in source.listSync(followLinks: false)) {
+  for (final FileSystemEntity entity in source.listSync(followLinks: false)) {
     final String name = path.basename(entity.path);
 
     if (entity is Directory) {
@@ -165,7 +165,7 @@ class SourceStats {
 SourceStats getStatsFor(Directory dir, [SourceStats stats]) {
   stats ??= SourceStats();
 
-  for (FileSystemEntity entity in dir.listSync(recursive: false, followLinks: false)) {
+  for (final FileSystemEntity entity in dir.listSync(recursive: false, followLinks: false)) {
     final String name = path.basename(entity.path);
     if (entity is File && name.endsWith('.dart')) {
       stats.files += 1;
diff --git a/dev/tools/update_icons.dart b/dev/tools/update_icons.dart
index d5b07b06b95..7b0128ad1b0 100644
--- a/dev/tools/update_icons.dart
+++ b/dev/tools/update_icons.dart
@@ -182,7 +182,7 @@ void main(List<String> args) {
 String regenerateIconsFile(String iconData, String codepointData) {
   final StringBuffer buf = StringBuffer();
   bool generating = false;
-  for (String line in LineSplitter.split(iconData)) {
+  for (final String line in LineSplitter.split(iconData)) {
     if (!generating)
       buf.writeln(line);
     if (line.contains(kBeginGeneratedMark)) {
diff --git a/dev/tools/vitool/bin/main.dart b/dev/tools/vitool/bin/main.dart
index 29d24d2bb39..9bab9d31da3 100644
--- a/dev/tools/vitool/bin/main.dart
+++ b/dev/tools/vitool/bin/main.dart
@@ -65,7 +65,7 @@ void main(List<String> args) {
   }
 
   final List<FrameData> frames = <FrameData>[
-    for (String filePath in argResults.rest) interpretSvg(filePath),
+    for (final String filePath in argResults.rest) interpretSvg(filePath),
   ];
 
   final StringBuffer generatedSb = StringBuffer();
diff --git a/dev/tools/vitool/lib/vitool.dart b/dev/tools/vitool/lib/vitool.dart
index 52e07e5a8de..df713c2535a 100644
--- a/dev/tools/vitool/lib/vitool.dart
+++ b/dev/tools/vitool/lib/vitool.dart
@@ -59,7 +59,7 @@ class Animation {
     sb.write('const $className $varName = const $className(\n');
     sb.write('${kIndent}const Size(${size.x}, ${size.y}),\n');
     sb.write('${kIndent}const <_PathFrames>[\n');
-    for (PathAnimation path in paths)
+    for (final PathAnimation path in paths)
       sb.write(path.toDart());
     sb.write('$kIndent],\n');
     sb.write(');');
@@ -117,11 +117,11 @@ class PathAnimation {
     final StringBuffer sb = StringBuffer();
     sb.write('${kIndent * 2}const _PathFrames(\n');
     sb.write('${kIndent * 3}opacities: const <double>[\n');
-    for (double opacity in opacities)
+    for (final double opacity in opacities)
       sb.write('${kIndent * 4}$opacity,\n');
     sb.write('${kIndent * 3}],\n');
     sb.write('${kIndent * 3}commands: const <_PathCommand>[\n');
-    for (PathCommandAnimation command in commands)
+    for (final PathCommandAnimation command in commands)
       sb.write(command.toDart());
     sb.write('${kIndent * 3}],\n');
     sb.write('${kIndent * 2}),\n');
@@ -166,9 +166,9 @@ class PathCommandAnimation {
     }
     final StringBuffer sb = StringBuffer();
     sb.write('${kIndent * 4}const $dartCommandClass(\n');
-    for (List<Point<double>> pointFrames in points) {
+    for (final List<Point<double>> pointFrames in points) {
       sb.write('${kIndent * 5}const <Offset>[\n');
-      for (Point<double> point in pointFrames)
+      for (final Point<double> point in pointFrames)
         sb.write('${kIndent * 6}const Offset(${point.x}, ${point.y}),\n');
       sb.write('${kIndent * 5}],\n');
     }
@@ -201,7 +201,7 @@ FrameData interpretSvg(String svgFilePath) {
 
 List<SvgPath> _interpretSvgGroup(List<XmlNode> children, _Transform transform) {
   final List<SvgPath> paths = <SvgPath>[];
-  for (XmlNode node in children) {
+  for (final XmlNode node in children) {
     if (node.nodeType != XmlNodeType.ELEMENT)
       continue;
     final XmlElement element = node as XmlElement;
@@ -304,7 +304,7 @@ class SvgPath {
     final SvgPathCommandBuilder commandsBuilder = SvgPathCommandBuilder();
     if (!_pathCommandValidator.hasMatch(dAttr))
       throw Exception('illegal or unsupported path d expression: $dAttr');
-    for (Match match in _pathCommandMatcher.allMatches(dAttr)) {
+    for (final Match match in _pathCommandMatcher.allMatches(dAttr)) {
       final String commandType = match.group(1);
       final String pointStr = match.group(2);
       commands.add(commandsBuilder.build(commandType, parsePoints(pointStr)));
@@ -469,7 +469,7 @@ Matrix3 _parseSvgTransform(String transform) {
     throw Exception('illegal or unsupported transform: $transform');
   final Iterable<Match> matches =_transformCommand.allMatches(transform).toList().reversed;
   Matrix3 result = Matrix3.identity();
-  for (Match m in matches) {
+  for (final Match m in matches) {
     final String command = m.group(1);
     final String params = m.group(2);
     if (command == 'translate') {
diff --git a/examples/catalog/bin/sample_page.dart b/examples/catalog/bin/sample_page.dart
index 2d22885266a..852e7180afb 100644
--- a/examples/catalog/bin/sample_page.dart
+++ b/examples/catalog/bin/sample_page.dart
@@ -146,7 +146,7 @@ void generate(String commit) {
   initialize();
 
   final List<SampleInfo> samples = <SampleInfo>[];
-  for (FileSystemEntity entity in sampleDirectory.listSync()) {
+  for (final FileSystemEntity entity in sampleDirectory.listSync()) {
     if (entity is File && entity.path.endsWith('.dart')) {
       final SampleInfo sample = SampleInfo(entity, commit);
       if (sample.initialize()) // skip files that lack the Sample Catalog comment
@@ -175,7 +175,7 @@ void generate(String commit) {
   );
 
   // Write the sample app files, like animated_list.md
-  for (SampleInfo sample in samples) {
+  for (final SampleInfo sample in samples) {
     writeExpandedTemplate(
       outputFile(sample.sourceName + '.md'),
       inputFile('bin', 'sample_page.md.template').readAsStringSync(),
@@ -188,13 +188,13 @@ void generate(String commit) {
   // that feature one class. For example AnimatedList_index.md would only
   // include samples that had AnimatedList in their "Classes:" list.
   final Map<String, List<SampleInfo>> classToSamples = <String, List<SampleInfo>>{};
-  for (SampleInfo sample in samples) {
-    for (String className in sample.highlightedClasses) {
+  for (final SampleInfo sample in samples) {
+    for (final String className in sample.highlightedClasses) {
       classToSamples[className] ??= <SampleInfo>[];
       classToSamples[className].add(sample);
     }
   }
-  for (String className in classToSamples.keys) {
+  for (final String className in classToSamples.keys) {
     final Iterable<String> entries = classToSamples[className].map<String>((SampleInfo sample) {
       return expandTemplate(entryTemplate, sample.commentValues);
     });
@@ -238,7 +238,7 @@ void generate(String commit) {
 
   // For now, the website's index.json file must be updated by hand.
   logMessage('The following entries must appear in _data/catalog/widgets.json');
-  for (String className in classToSamples.keys)
+  for (final String className in classToSamples.keys)
     logMessage('"sample": "${className}_index"');
 }
 
diff --git a/examples/catalog/test/expansion_tile_sample_test.dart b/examples/catalog/test/expansion_tile_sample_test.dart
index 02b996bc918..9188652da23 100644
--- a/examples/catalog/test/expansion_tile_sample_test.dart
+++ b/examples/catalog/test/expansion_tile_sample_test.dart
@@ -13,11 +13,11 @@ void main() {
     await tester.pump();
 
     // Initially only the top level EntryItems (the "chapters") are present.
-    for (Entry chapter in expansion_tile_sample.data) {
+    for (final Entry chapter in expansion_tile_sample.data) {
       expect(find.text(chapter.title), findsOneWidget);
-      for (Entry section in chapter.children) {
+      for (final Entry section in chapter.children) {
         expect(find.text(section.title), findsNothing);
-        for (Entry item in section.children)
+        for (final Entry item in section.children)
           expect(find.text(item.title), findsNothing);
       }
     }
@@ -34,15 +34,15 @@ void main() {
 
     // Expand the chapters. Now the chapter and sections, but not the
     // items, should be present.
-    for (Entry chapter in expansion_tile_sample.data.reversed)
+    for (final Entry chapter in expansion_tile_sample.data.reversed)
       await tapEntry(chapter.title);
 
-    for (Entry chapter in expansion_tile_sample.data) {
+    for (final Entry chapter in expansion_tile_sample.data) {
       expect(find.text(chapter.title), findsOneWidget);
-      for (Entry section in chapter.children) {
+      for (final Entry section in chapter.children) {
         expect(find.text(section.title), findsOneWidget);
         await scrollUpOneEntry();
-        for (Entry item in section.children)
+        for (final Entry item in section.children)
           expect(find.text(item.title), findsNothing);
       }
       await scrollUpOneEntry();
@@ -53,8 +53,8 @@ void main() {
     await tester.pumpAndSettle();
 
     // Expand the sections. Now Widgets for all three levels should be present.
-    for (Entry chapter in expansion_tile_sample.data) {
-      for (Entry section in chapter.children) {
+    for (final Entry chapter in expansion_tile_sample.data) {
+      for (final Entry section in chapter.children) {
         await tapEntry(section.title);
         await scrollUpOneEntry();
       }
@@ -65,11 +65,11 @@ void main() {
     // Working in reverse order, so we don't need to do anymore scrolling,
     // check that everything is visible and close the sections and
     // chapters as we go up.
-    for (Entry chapter in expansion_tile_sample.data.reversed) {
+    for (final Entry chapter in expansion_tile_sample.data.reversed) {
       expect(find.text(chapter.title), findsOneWidget);
-      for (Entry section in chapter.children.reversed) {
+      for (final Entry section in chapter.children.reversed) {
         expect(find.text(section.title), findsOneWidget);
-        for (Entry item in section.children.reversed)
+        for (final Entry item in section.children.reversed)
           expect(find.text(item.title), findsOneWidget);
         await tapEntry(section.title); // close the section
       }
@@ -77,11 +77,11 @@ void main() {
     }
 
     // Finally only the top level EntryItems (the "chapters") are present.
-    for (Entry chapter in expansion_tile_sample.data) {
+    for (final Entry chapter in expansion_tile_sample.data) {
       expect(find.text(chapter.title), findsOneWidget);
-      for (Entry section in chapter.children) {
+      for (final Entry section in chapter.children) {
         expect(find.text(section.title), findsNothing);
-        for (Entry item in section.children)
+        for (final Entry item in section.children)
           expect(find.text(item.title), findsNothing);
       }
     }
diff --git a/examples/flutter_gallery/lib/demo/material/bottom_navigation_demo.dart b/examples/flutter_gallery/lib/demo/material/bottom_navigation_demo.dart
index b4faf8821d4..6c2f4a55c43 100644
--- a/examples/flutter_gallery/lib/demo/material/bottom_navigation_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/bottom_navigation_demo.dart
@@ -158,14 +158,14 @@ class _BottomNavigationDemoState extends State<BottomNavigationDemo>
 
   @override
   void dispose() {
-    for (NavigationIconView view in _navigationViews)
+    for (final NavigationIconView view in _navigationViews)
       view.controller.dispose();
     super.dispose();
   }
 
   Widget _buildTransitionsStack() {
     final List<FadeTransition> transitions = <FadeTransition>[
-      for (NavigationIconView view in _navigationViews) view.transition(_type, context),
+      for (final NavigationIconView view in _navigationViews) view.transition(_type, context),
     ];
 
     // We want to have the newly animating (fading in) views on top.
diff --git a/examples/flutter_gallery/lib/demo/material/chip_demo.dart b/examples/flutter_gallery/lib/demo/material/chip_demo.dart
index 15cd6451a6f..2ab9f9bc69e 100644
--- a/examples/flutter_gallery/lib/demo/material/chip_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/chip_demo.dart
@@ -260,7 +260,7 @@ class _ChipDemoState extends State<ChipDemo> {
 
     Set<String> allowedActions = <String>{};
     if (_selectedMaterial != null && _selectedMaterial.isNotEmpty) {
-      for (String tool in _selectedTools) {
+      for (final String tool in _selectedTools) {
         allowedActions.addAll(_toolActions[tool]);
       }
       allowedActions = allowedActions.intersection(_materialActions[_selectedMaterial]);
diff --git a/examples/flutter_gallery/lib/demo/material/data_table_demo.dart b/examples/flutter_gallery/lib/demo/material/data_table_demo.dart
index 7108f07cff9..da59408583a 100644
--- a/examples/flutter_gallery/lib/demo/material/data_table_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/data_table_demo.dart
@@ -135,7 +135,7 @@ class DessertDataSource extends DataTableSource {
   int get selectedRowCount => _selectedCount;
 
   void _selectAll(bool checked) {
-    for (Dessert dessert in _desserts)
+    for (final Dessert dessert in _desserts)
       dessert.selected = checked;
     _selectedCount = checked ? _desserts.length : 0;
     notifyListeners();
diff --git a/examples/flutter_gallery/lib/demo/shrine/expanding_bottom_sheet.dart b/examples/flutter_gallery/lib/demo/shrine/expanding_bottom_sheet.dart
index 3841d90a4e3..0e6130e459b 100644
--- a/examples/flutter_gallery/lib/demo/shrine/expanding_bottom_sheet.dart
+++ b/examples/flutter_gallery/lib/demo/shrine/expanding_bottom_sheet.dart
@@ -476,7 +476,7 @@ class _ProductThumbnailRowState extends State<ProductThumbnailRow> {
       return;
     }
 
-    for (int product in difference) {
+    for (final int product in difference) {
       if (_internalList.length < _list.length) {
         _list.remove(product);
       } else if (_internalList.length > _list.length) {
diff --git a/examples/flutter_gallery/lib/demo/video_demo.dart b/examples/flutter_gallery/lib/demo/video_demo.dart
index aa30d9a1c19..b5beb6f212b 100644
--- a/examples/flutter_gallery/lib/demo/video_demo.dart
+++ b/examples/flutter_gallery/lib/demo/video_demo.dart
@@ -294,8 +294,7 @@ class _ConnectivityOverlayState extends State<ConnectivityOverlay> {
     final Connectivity connectivity = Connectivity();
     ConnectivityResult previousResult = await connectivity.checkConnectivity();
     yield previousResult;
-    await for (ConnectivityResult result
-        in connectivity.onConnectivityChanged) {
+    await for (final ConnectivityResult result in connectivity.onConnectivityChanged) {
       if (result != previousResult) {
         yield result;
         previousResult = result;
diff --git a/examples/flutter_gallery/lib/gallery/example_code_parser.dart b/examples/flutter_gallery/lib/gallery/example_code_parser.dart
index f37f587d1b3..06e602bc8ec 100644
--- a/examples/flutter_gallery/lib/gallery/example_code_parser.dart
+++ b/examples/flutter_gallery/lib/gallery/example_code_parser.dart
@@ -27,7 +27,7 @@ Future<void> _parseExampleCode(AssetBundle bundle) async {
   List<String> codeBlock;
   String codeTag;
 
-  for (String line in lines) {
+  for (final String line in lines) {
     if (codeBlock == null) {
       // Outside a block.
       if (line.startsWith(_kStartTag)) {
diff --git a/examples/flutter_gallery/lib/gallery/syntax_highlighter.dart b/examples/flutter_gallery/lib/gallery/syntax_highlighter.dart
index a56368d7d7c..a2023b270d1 100644
--- a/examples/flutter_gallery/lib/gallery/syntax_highlighter.dart
+++ b/examples/flutter_gallery/lib/gallery/syntax_highlighter.dart
@@ -94,7 +94,7 @@ class DartSyntaxHighlighter extends SyntaxHighlighter {
       final List<TextSpan> formattedText = <TextSpan>[];
       int currentPosition = 0;
 
-      for (_HighlightSpan span in _spans) {
+      for (final _HighlightSpan span in _spans) {
         if (currentPosition != span.start)
           formattedText.add(TextSpan(text: _src.substring(currentPosition, span.start)));
 
diff --git a/examples/flutter_gallery/test/live_smoketest.dart b/examples/flutter_gallery/test/live_smoketest.dart
index cfae8d34ac1..76d6c0d81b3 100644
--- a/examples/flutter_gallery/test/live_smoketest.dart
+++ b/examples/flutter_gallery/test/live_smoketest.dart
@@ -61,10 +61,10 @@ Future<void> main() async {
     print('Starting app...');
     runApp(const GalleryApp(testMode: true));
     final _LiveWidgetController controller = _LiveWidgetController(WidgetsBinding.instance);
-    for (GalleryDemoCategory category in kAllGalleryDemoCategories) {
+    for (final GalleryDemoCategory category in kAllGalleryDemoCategories) {
       print('Tapping "${category.name}" section...');
       await controller.tap(find.text(category.name));
-      for (GalleryDemo demo in kGalleryCategoryToDemos[category]) {
+      for (final GalleryDemo demo in kGalleryCategoryToDemos[category]) {
         final Finder demoItem = find.text(demo.title);
         print('Scrolling to "${demo.title}"...');
         await controller.scrollIntoView(demoItem, alignment: 0.5);
diff --git a/examples/flutter_gallery/test/smoke_test.dart b/examples/flutter_gallery/test/smoke_test.dart
index 48ac18ba250..b91e64869bf 100644
--- a/examples/flutter_gallery/test/smoke_test.dart
+++ b/examples/flutter_gallery/test/smoke_test.dart
@@ -42,7 +42,7 @@ void verifyToStringOutput(String name, String route, String testString) {
   final List<String> lines = testString.split('\n');
   if (!testString.endsWith('\n'))
     reportToStringError(name, route, lines.length, lines, 'does not end with a line feed');
-  for (String line in lines) {
+  for (final String line in lines) {
     lineNumber += 1;
     if (line == '' && lineNumber != lines.length) {
       reportToStringError(name, route, lineNumber, lines, 'found empty line');
@@ -157,11 +157,11 @@ Future<void> smokeGallery(WidgetTester tester) async {
 
   expect(find.text(kGalleryTitle), findsOneWidget);
 
-  for (GalleryDemoCategory category in kAllGalleryDemoCategories) {
+  for (final GalleryDemoCategory category in kAllGalleryDemoCategories) {
     await Scrollable.ensureVisible(tester.element(find.text(category.name)), alignment: 0.5);
     await tester.tap(find.text(category.name));
     await tester.pumpAndSettle();
-    for (GalleryDemo demo in kGalleryCategoryToDemos[category]) {
+    for (final GalleryDemo demo in kGalleryCategoryToDemos[category]) {
       await Scrollable.ensureVisible(tester.element(find.text(demo.title)), alignment: 0.0);
       await smokeDemo(tester, demo);
       tester.binding.debugAssertNoTransientCallbacks('A transient callback was still active after running $demo');
diff --git a/examples/flutter_gallery/test_driver/transitions_perf_test.dart b/examples/flutter_gallery/test_driver/transitions_perf_test.dart
index 2fd1a188be3..0f32b944e64 100644
--- a/examples/flutter_gallery/test_driver/transitions_perf_test.dart
+++ b/examples/flutter_gallery/test_driver/transitions_perf_test.dart
@@ -69,7 +69,7 @@ Future<void> saveDurationsHistogram(List<Map<String, dynamic>> events, String ou
   int frameStart;
 
   // Save the duration of the first frame after each 'Start Transition' event.
-  for (Map<String, dynamic> event in events) {
+  for (final Map<String, dynamic> event in events) {
     final String eventName = event['name'] as String;
     if (eventName == 'Start Transition') {
       assert(startEvent == null);
@@ -143,7 +143,7 @@ Future<void> runDemos(List<String> demos, FlutterDriver driver) async {
   final SerializableFinder demoList = find.byValueKey('GalleryDemoList');
   String currentDemoCategory;
 
-  for (String demo in demos) {
+  for (final String demo in demos) {
     if (kSkippedDemos.contains(demo))
       continue;
 
diff --git a/examples/layers/raw/touch_input.dart b/examples/layers/raw/touch_input.dart
index 53aff0fe151..370c137f2fd 100644
--- a/examples/layers/raw/touch_input.dart
+++ b/examples/layers/raw/touch_input.dart
@@ -79,7 +79,7 @@ void beginFrame(Duration timeStamp) {
 void handlePointerDataPacket(ui.PointerDataPacket packet) {
   // The pointer packet contains a number of pointer movements, which we iterate
   // through and process.
-  for (ui.PointerData datum in packet.data) {
+  for (final ui.PointerData datum in packet.data) {
     if (datum.change == ui.PointerChange.down) {
       // If the pointer went down, we change the color of the circle to blue.
       color = const ui.Color(0xFF0000FF);
diff --git a/examples/layers/rendering/touch_input.dart b/examples/layers/rendering/touch_input.dart
index 149fcf16296..928fea7e3ab 100644
--- a/examples/layers/rendering/touch_input.dart
+++ b/examples/layers/rendering/touch_input.dart
@@ -94,7 +94,7 @@ class RenderDots extends RenderBox {
     canvas.drawRect(offset & size, Paint()..color = const Color(0xFFFFFFFF));
 
     // We iterate through our model and paint each dot.
-    for (Dot dot in _dots.values)
+    for (final Dot dot in _dots.values)
       dot.paint(canvas, offset);
   }
 }
diff --git a/examples/layers/widgets/custom_render_box.dart b/examples/layers/widgets/custom_render_box.dart
index 878aa646d87..ae914d1e0f3 100644
--- a/examples/layers/widgets/custom_render_box.dart
+++ b/examples/layers/widgets/custom_render_box.dart
@@ -31,7 +31,7 @@ class RenderDots extends RenderConstrainedBox {
     canvas.drawRect(offset & size, Paint()..color = const Color(0xFF0000FF));
 
     final Paint paint = Paint()..color = const Color(0xFF00FF00);
-    for (Offset point in _dots.values)
+    for (final Offset point in _dots.values)
       canvas.drawCircle(point, 50.0, paint);
 
     super.paint(context, offset);
diff --git a/examples/stocks/lib/stock_data.dart b/examples/stocks/lib/stock_data.dart
index 8451c5fe236..35a79cae52e 100644
--- a/examples/stocks/lib/stock_data.dart
+++ b/examples/stocks/lib/stock_data.dart
@@ -56,7 +56,7 @@ class StockData extends ChangeNotifier {
   bool get loading => _httpClient != null;
 
   void add(List<dynamic> data) {
-    for (List<dynamic> fields in data.cast<List<dynamic>>()) {
+    for (final List<dynamic> fields in data.cast<List<dynamic>>()) {
       final Stock stock = Stock.fromFields(fields.cast<String>());
       _symbols.add(stock.symbol);
       _stocks[stock.symbol] = stock;
diff --git a/packages/flutter/lib/src/animation/listener_helpers.dart b/packages/flutter/lib/src/animation/listener_helpers.dart
index 61203f8f3de..e8d66c7adca 100644
--- a/packages/flutter/lib/src/animation/listener_helpers.dart
+++ b/packages/flutter/lib/src/animation/listener_helpers.dart
@@ -118,7 +118,7 @@ mixin AnimationLocalListenersMixin {
   /// will not change which listeners are called during this iteration.
   void notifyListeners() {
     final List<VoidCallback> localListeners = List<VoidCallback>.from(_listeners);
-    for (VoidCallback listener in localListeners) {
+    for (final VoidCallback listener in localListeners) {
       try {
         if (_listeners.contains(listener))
           listener();
@@ -187,7 +187,7 @@ mixin AnimationLocalStatusListenersMixin {
   /// will not change which listeners are called during this iteration.
   void notifyStatusListeners(AnimationStatus status) {
     final List<AnimationStatusListener> localListeners = List<AnimationStatusListener>.from(_statusListeners);
-    for (AnimationStatusListener listener in localListeners) {
+    for (final AnimationStatusListener listener in localListeners) {
       try {
         if (_statusListeners.contains(listener))
           listener(status);
diff --git a/packages/flutter/lib/src/animation/tween_sequence.dart b/packages/flutter/lib/src/animation/tween_sequence.dart
index bb6fa5b9bf7..3d1712a239b 100644
--- a/packages/flutter/lib/src/animation/tween_sequence.dart
+++ b/packages/flutter/lib/src/animation/tween_sequence.dart
@@ -57,7 +57,7 @@ class TweenSequence<T> extends Animatable<T> {
     _items.addAll(items);
 
     double totalWeight = 0.0;
-    for (TweenSequenceItem<T> item in _items)
+    for (final TweenSequenceItem<T> item in _items)
       totalWeight += item.weight;
     assert(totalWeight > 0.0);
 
diff --git a/packages/flutter/lib/src/cupertino/date_picker.dart b/packages/flutter/lib/src/cupertino/date_picker.dart
index fab27b4057d..29c547f1032 100644
--- a/packages/flutter/lib/src/cupertino/date_picker.dart
+++ b/packages/flutter/lib/src/cupertino/date_picker.dart
@@ -1572,7 +1572,7 @@ class _CupertinoTimerPickerState extends State<CupertinoTimerPicker> {
     //   that has the biggest width.
     // - If two different 1-digit numbers are of the same width, their corresponding
     //   2 digit numbers are of the same width.
-    for (String input in numbers) {
+    for (final String input in numbers) {
       textPainter.text = TextSpan(
         text: input,
         style: textStyle,
diff --git a/packages/flutter/lib/src/cupertino/segmented_control.dart b/packages/flutter/lib/src/cupertino/segmented_control.dart
index 6a66b3d1681..fa721391734 100644
--- a/packages/flutter/lib/src/cupertino/segmented_control.dart
+++ b/packages/flutter/lib/src/cupertino/segmented_control.dart
@@ -257,13 +257,13 @@ class _SegmentedControlState<T> extends State<CupertinoSegmentedControl<T>>
 
   void _updateAnimationControllers() {
     assert(mounted, 'This should only be called after didUpdateDependencies');
-    for (AnimationController controller in _selectionControllers) {
+    for (final AnimationController controller in _selectionControllers) {
       controller.dispose();
     }
     _selectionControllers.clear();
     _childTweens.clear();
 
-    for (T key in widget.children.keys) {
+    for (final T key in widget.children.keys) {
       final AnimationController animationController = createAnimationController();
       if (widget.groupValue == key) {
         _childTweens.add(_reverseBackgroundColorTween);
@@ -294,7 +294,7 @@ class _SegmentedControlState<T> extends State<CupertinoSegmentedControl<T>>
 
     if (oldWidget.groupValue != widget.groupValue) {
       int index = 0;
-      for (T key in widget.children.keys) {
+      for (final T key in widget.children.keys) {
         if (widget.groupValue == key) {
           _childTweens[index] = _forwardBackgroundColorTween;
           _selectionControllers[index].forward();
@@ -309,7 +309,7 @@ class _SegmentedControlState<T> extends State<CupertinoSegmentedControl<T>>
 
   @override
   void dispose() {
-    for (AnimationController animationController in _selectionControllers) {
+    for (final AnimationController animationController in _selectionControllers) {
       animationController.dispose();
     }
     super.dispose();
@@ -364,7 +364,7 @@ class _SegmentedControlState<T> extends State<CupertinoSegmentedControl<T>>
     int index = 0;
     int selectedIndex;
     int pressedIndex;
-    for (T currentKey in widget.children.keys) {
+    for (final T currentKey in widget.children.keys) {
       selectedIndex = (widget.groupValue == currentKey) ? index : selectedIndex;
       pressedIndex = (_pressedKey == currentKey) ? index : pressedIndex;
 
@@ -629,7 +629,7 @@ class _RenderSegmentedControl<T> extends RenderBox
     double maxHeight = _kMinSegmentedControlHeight;
 
     double childWidth = constraints.minWidth / childCount;
-    for (RenderBox child in getChildrenAsList()) {
+    for (final RenderBox child in getChildrenAsList()) {
       childWidth = math.max(childWidth, child.getMaxIntrinsicWidth(double.infinity));
     }
     childWidth = math.min(childWidth, constraints.maxWidth / childCount);
diff --git a/packages/flutter/lib/src/cupertino/sliding_segmented_control.dart b/packages/flutter/lib/src/cupertino/sliding_segmented_control.dart
index 2456693432b..78f68c637e5 100644
--- a/packages/flutter/lib/src/cupertino/sliding_segmented_control.dart
+++ b/packages/flutter/lib/src/cupertino/sliding_segmented_control.dart
@@ -301,7 +301,7 @@ class _SegmentedControlState<T> extends State<CupertinoSlidingSegmentedControl<T
       vsync: this,
     );
 
-    for (T currentKey in widget.children.keys) {
+    for (final T currentKey in widget.children.keys) {
       _highlightControllers[currentKey] = _createHighlightAnimationController(
         isCompleted: currentKey == widget.groupValue,  // Highlight the current selection.
       );
@@ -314,7 +314,7 @@ class _SegmentedControlState<T> extends State<CupertinoSlidingSegmentedControl<T
     super.didUpdateWidget(oldWidget);
 
     // Update animation controllers.
-    for (T oldKey in oldWidget.children.keys) {
+    for (final T oldKey in oldWidget.children.keys) {
       if (!widget.children.containsKey(oldKey)) {
         _highlightControllers[oldKey].dispose();
         _pressControllers[oldKey].dispose();
@@ -324,7 +324,7 @@ class _SegmentedControlState<T> extends State<CupertinoSlidingSegmentedControl<T
       }
     }
 
-    for (T newKey in widget.children.keys) {
+    for (final T newKey in widget.children.keys) {
       if (!_highlightControllers.keys.contains(newKey)) {
         _highlightControllers[newKey] = _createHighlightAnimationController();
         _pressControllers[newKey] = _createFadeoutAnimationController();
@@ -336,11 +336,11 @@ class _SegmentedControlState<T> extends State<CupertinoSlidingSegmentedControl<T
 
   @override
   void dispose() {
-    for (AnimationController animationController in _highlightControllers.values) {
+    for (final AnimationController animationController in _highlightControllers.values) {
       animationController.dispose();
     }
 
-    for (AnimationController animationController in _pressControllers.values) {
+    for (final AnimationController animationController in _pressControllers.values) {
       animationController.dispose();
     }
 
@@ -413,7 +413,7 @@ class _SegmentedControlState<T> extends State<CupertinoSlidingSegmentedControl<T
       ]),
       builder: (BuildContext context, Widget child) {
         final List<Widget> children = <Widget>[];
-        for (T currentKey in keys) {
+        for (final T currentKey in keys) {
           final TextStyle textStyle = DefaultTextStyle.of(context).style.copyWith(
             fontWeight: _highlightTween.evaluate(_highlightControllers[currentKey]),
           );
@@ -829,7 +829,7 @@ class _RenderSegmentedControl<T> extends RenderBox
     double childWidth = (constraints.minWidth - totalSeparatorWidth) / childCount;
     double maxHeight = _kMinSegmentedControlHeight;
 
-    for (RenderBox child in getChildrenAsList()) {
+    for (final RenderBox child in getChildrenAsList()) {
       childWidth = math.max(childWidth, child.getMaxIntrinsicWidth(double.infinity) + 2 * _kSegmentMinPadding);
     }
 
@@ -999,7 +999,7 @@ class _RenderSegmentedControl<T> extends RenderBox
 
     final RRect thumbRRect = RRect.fromRectAndRadius(thumbRect.shift(offset), _kThumbRadius);
 
-    for (BoxShadow shadow in thumbShadow) {
+    for (final BoxShadow shadow in thumbShadow) {
       context.canvas.drawRRect(thumbRRect.shift(shadow.offset), shadow.toPaint());
     }
 
diff --git a/packages/flutter/lib/src/cupertino/tab_scaffold.dart b/packages/flutter/lib/src/cupertino/tab_scaffold.dart
index 5e013a98c9a..96c9b751210 100644
--- a/packages/flutter/lib/src/cupertino/tab_scaffold.dart
+++ b/packages/flutter/lib/src/cupertino/tab_scaffold.dart
@@ -523,10 +523,10 @@ class _TabSwitchingViewState extends State<_TabSwitchingView> {
 
   @override
   void dispose() {
-    for (FocusScopeNode focusScopeNode in tabFocusNodes) {
+    for (final FocusScopeNode focusScopeNode in tabFocusNodes) {
       focusScopeNode.dispose();
     }
-    for (FocusScopeNode focusScopeNode in discardedNodes) {
+    for (final FocusScopeNode focusScopeNode in discardedNodes) {
       focusScopeNode.dispose();
     }
     super.dispose();
diff --git a/packages/flutter/lib/src/cupertino/thumb_painter.dart b/packages/flutter/lib/src/cupertino/thumb_painter.dart
index 19256122b93..c5a56c1c037 100644
--- a/packages/flutter/lib/src/cupertino/thumb_painter.dart
+++ b/packages/flutter/lib/src/cupertino/thumb_painter.dart
@@ -79,7 +79,7 @@ class CupertinoThumbPainter {
       Radius.circular(rect.shortestSide / 2.0),
     );
 
-    for (BoxShadow shadow in shadows)
+    for (final BoxShadow shadow in shadows)
       canvas.drawRRect(rrect.shift(shadow.offset), shadow.toPaint());
 
     canvas.drawRRect(
diff --git a/packages/flutter/lib/src/foundation/assertions.dart b/packages/flutter/lib/src/foundation/assertions.dart
index 0c88184b337..7f4ffed2cb4 100644
--- a/packages/flutter/lib/src/foundation/assertions.dart
+++ b/packages/flutter/lib/src/foundation/assertions.dart
@@ -556,7 +556,7 @@ class FlutterError extends Error with DiagnosticableTreeMixin implements Asserti
           ErrorDescription('\nThe malformed error has ${summaries.length} summaries.'),
         ];
         int i = 1;
-        for (DiagnosticsNode summary in summaries) {
+        for (final DiagnosticsNode summary in summaries) {
           message.add(DiagnosticsProperty<DiagnosticsNode>('Summary $i', summary, expandableValue : true));
           i += 1;
         }
@@ -683,7 +683,7 @@ class FlutterError extends Error with DiagnosticableTreeMixin implements Asserti
     final RegExp packageParser = RegExp(r'^([^:]+):(.+)$');
     final List<String> result = <String>[];
     final List<String> skipped = <String>[];
-    for (String line in frames) {
+    for (final String line in frames) {
       final Match match = stackParser.firstMatch(line);
       if (match != null) {
         assert(match.groupCount == 2);
@@ -834,7 +834,7 @@ class _FlutterErrorDetailsNode extends DiagnosticableNode<FlutterErrorDetails> {
       return null;
     }
     Iterable<DiagnosticsNode> properties = builder.properties;
-    for (DiagnosticPropertiesTransformer transformer in FlutterErrorDetails.propertiesTransformers) {
+    for (final DiagnosticPropertiesTransformer transformer in FlutterErrorDetails.propertiesTransformers) {
       properties = transformer(properties);
     }
     return DiagnosticPropertiesBuilder.fromProperties(properties.toList());
diff --git a/packages/flutter/lib/src/foundation/change_notifier.dart b/packages/flutter/lib/src/foundation/change_notifier.dart
index 4174f0b05ca..3f7cac30d81 100644
--- a/packages/flutter/lib/src/foundation/change_notifier.dart
+++ b/packages/flutter/lib/src/foundation/change_notifier.dart
@@ -200,7 +200,7 @@ class ChangeNotifier implements Listenable {
     assert(_debugAssertNotDisposed());
     if (_listeners != null) {
       final List<VoidCallback> localListeners = List<VoidCallback>.from(_listeners);
-      for (VoidCallback listener in localListeners) {
+      for (final VoidCallback listener in localListeners) {
         try {
           if (_listeners.contains(listener))
             listener();
diff --git a/packages/flutter/lib/src/foundation/collections.dart b/packages/flutter/lib/src/foundation/collections.dart
index 5fabaeb7062..9caeb50017a 100644
--- a/packages/flutter/lib/src/foundation/collections.dart
+++ b/packages/flutter/lib/src/foundation/collections.dart
@@ -26,7 +26,7 @@ bool setEquals<T>(Set<T> a, Set<T> b) {
     return false;
   if (identical(a, b))
     return true;
-  for (T value in a) {
+  for (final T value in a) {
     if (!b.contains(value))
       return false;
   }
@@ -84,7 +84,7 @@ bool mapEquals<T, U>(Map<T, U> a, Map<T, U> b) {
     return false;
   if (identical(a, b))
     return true;
-  for (T key in a.keys) {
+  for (final T key in a.keys) {
     if (!b.containsKey(key) || b[key] != a[key]) {
       return false;
     }
diff --git a/packages/flutter/lib/src/foundation/consolidate_response.dart b/packages/flutter/lib/src/foundation/consolidate_response.dart
index f1f770095ad..a41d84a6e72 100644
--- a/packages/flutter/lib/src/foundation/consolidate_response.dart
+++ b/packages/flutter/lib/src/foundation/consolidate_response.dart
@@ -115,7 +115,7 @@ class _OutputBuffer extends ByteConversionSinkBase {
     }
     _bytes = Uint8List(_contentLength);
     int offset = 0;
-    for (List<int> chunk in _chunks) {
+    for (final List<int> chunk in _chunks) {
       _bytes.setRange(offset, offset + chunk.length, chunk);
       offset += chunk.length;
     }
diff --git a/packages/flutter/lib/src/foundation/diagnostics.dart b/packages/flutter/lib/src/foundation/diagnostics.dart
index 5fa29c27b6c..104532529c1 100644
--- a/packages/flutter/lib/src/foundation/diagnostics.dart
+++ b/packages/flutter/lib/src/foundation/diagnostics.dart
@@ -843,7 +843,7 @@ class _PrefixedStringBuilder {
     );
     int i = 0;
     final int length = lines.length;
-    for (String line in lines) {
+    for (final String line in lines) {
       i++;
       _writeLine(
         line,
@@ -1132,7 +1132,7 @@ class TextTreeRenderer {
       const int maxLines = 25;
       int lines = 0;
       void visitor(DiagnosticsNode node) {
-        for (DiagnosticsNode child in node.getChildren()) {
+        for (final DiagnosticsNode child in node.getChildren()) {
           if (lines < maxLines) {
             depth += 1;
             descendants.add('$prefixOtherLines${"  " * depth}$child');
@@ -2508,7 +2508,7 @@ class FlagsSummary<T> extends DiagnosticsProperty<Map<String, T>> {
   // For a null value, it is omitted unless `includeEmtpy` is true and
   // [ifEntryNull] contains a corresponding description.
   Iterable<String> _formattedValues() sync* {
-    for (MapEntry<String, T> entry in value.entries) {
+    for (final MapEntry<String, T> entry in value.entries) {
       if (entry.value != null) {
         yield entry.key;
       }
diff --git a/packages/flutter/lib/src/foundation/licenses.dart b/packages/flutter/lib/src/foundation/licenses.dart
index fcda6ac42b9..084b95440a9 100644
--- a/packages/flutter/lib/src/foundation/licenses.dart
+++ b/packages/flutter/lib/src/foundation/licenses.dart
@@ -310,7 +310,7 @@ class LicenseRegistry {
   static Stream<LicenseEntry> get licenses async* {
     if (_collectors == null)
       return;
-    for (LicenseEntryCollector collector in _collectors)
+    for (final LicenseEntryCollector collector in _collectors)
       yield* collector();
   }
 
diff --git a/packages/flutter/lib/src/gestures/arena.dart b/packages/flutter/lib/src/gestures/arena.dart
index 47046eeaa63..d59ab635ca8 100644
--- a/packages/flutter/lib/src/gestures/arena.dart
+++ b/packages/flutter/lib/src/gestures/arena.dart
@@ -256,7 +256,7 @@ class GestureArenaManager {
     assert(state.eagerWinner == null || state.eagerWinner == member);
     assert(!state.isOpen);
     _arenas.remove(pointer);
-    for (GestureArenaMember rejectedMember in state.members) {
+    for (final GestureArenaMember rejectedMember in state.members) {
       if (rejectedMember != member)
         rejectedMember.rejectGesture(pointer);
     }
diff --git a/packages/flutter/lib/src/gestures/binding.dart b/packages/flutter/lib/src/gestures/binding.dart
index 1a10df47058..55e7174e04c 100644
--- a/packages/flutter/lib/src/gestures/binding.dart
+++ b/packages/flutter/lib/src/gestures/binding.dart
@@ -193,7 +193,7 @@ mixin GestureBinding on BindingBase implements HitTestable, HitTestDispatcher, H
       }
       return;
     }
-    for (HitTestEntry entry in hitTestResult.path) {
+    for (final HitTestEntry entry in hitTestResult.path) {
       try {
         entry.target.handleEvent(event.transformed(entry.transform), entry);
       } catch (exception, stack) {
diff --git a/packages/flutter/lib/src/gestures/converter.dart b/packages/flutter/lib/src/gestures/converter.dart
index a93a262dc73..0093c26b0bf 100644
--- a/packages/flutter/lib/src/gestures/converter.dart
+++ b/packages/flutter/lib/src/gestures/converter.dart
@@ -42,7 +42,7 @@ class PointerEventConverter {
   /// from physical coordinates to logical pixels. See the discussion at
   /// [PointerEvent] for more details on the [PointerEvent] coordinate space.
   static Iterable<PointerEvent> expand(Iterable<ui.PointerData> data, double devicePixelRatio) sync* {
-    for (ui.PointerData datum in data) {
+    for (final ui.PointerData datum in data) {
       final Offset position = Offset(datum.physicalX, datum.physicalY) / devicePixelRatio;
       final Offset delta = Offset(datum.physicalDeltaX, datum.physicalDeltaY) / devicePixelRatio;
       final double radiusMinor = _toLogicalPixels(datum.radiusMinor, devicePixelRatio);
diff --git a/packages/flutter/lib/src/gestures/mouse_tracking.dart b/packages/flutter/lib/src/gestures/mouse_tracking.dart
index 563b12ba832..c8e42c125a1 100644
--- a/packages/flutter/lib/src/gestures/mouse_tracking.dart
+++ b/packages/flutter/lib/src/gestures/mouse_tracking.dart
@@ -410,7 +410,7 @@ class MouseTracker extends ChangeNotifier {
     // We can safely use `_mouseStates` here without worrying about the removed
     // state, because `targetEvent` should be null when `_mouseStates` is used.
     final Iterable<_MouseState> dirtyStates = targetEvent == null ? _mouseStates.values : <_MouseState>[targetState];
-    for (_MouseState dirtyState in dirtyStates) {
+    for (final _MouseState dirtyState in dirtyStates) {
       final LinkedHashSet<MouseTrackerAnnotation> nextAnnotations = _findAnnotations(dirtyState);
       final LinkedHashSet<MouseTrackerAnnotation> lastAnnotations = dirtyState.replaceAnnotations(nextAnnotations);
       handleUpdatedDevice(dirtyState, lastAnnotations);
diff --git a/packages/flutter/lib/src/gestures/multitap.dart b/packages/flutter/lib/src/gestures/multitap.dart
index 57e9a7b5bfd..ed31657a015 100644
--- a/packages/flutter/lib/src/gestures/multitap.dart
+++ b/packages/flutter/lib/src/gestures/multitap.dart
@@ -505,7 +505,7 @@ class MultiTapGestureRecognizer extends GestureRecognizer {
   @override
   void dispose() {
     final List<_TapGesture> localGestures = List<_TapGesture>.from(_gestureMap.values);
-    for (_TapGesture gesture in localGestures)
+    for (final _TapGesture gesture in localGestures)
       gesture.cancel();
     // Rejection of each gesture should cause it to be removed from our map
     assert(_gestureMap.isEmpty);
diff --git a/packages/flutter/lib/src/gestures/recognizer.dart b/packages/flutter/lib/src/gestures/recognizer.dart
index 3b988c1e046..af81933d47d 100644
--- a/packages/flutter/lib/src/gestures/recognizer.dart
+++ b/packages/flutter/lib/src/gestures/recognizer.dart
@@ -251,7 +251,7 @@ abstract class OneSequenceGestureRecognizer extends GestureRecognizer {
   void resolve(GestureDisposition disposition) {
     final List<GestureArenaEntry> localEntries = List<GestureArenaEntry>.from(_entries.values);
     _entries.clear();
-    for (GestureArenaEntry entry in localEntries)
+    for (final GestureArenaEntry entry in localEntries)
       entry.resolve(disposition);
   }
 
@@ -270,7 +270,7 @@ abstract class OneSequenceGestureRecognizer extends GestureRecognizer {
   @override
   void dispose() {
     resolve(GestureDisposition.rejected);
-    for (int pointer in _trackedPointers)
+    for (final int pointer in _trackedPointers)
       GestureBinding.instance.pointerRouter.removeRoute(pointer, handleEvent);
     _trackedPointers.clear();
     assert(_entries.isEmpty);
diff --git a/packages/flutter/lib/src/gestures/scale.dart b/packages/flutter/lib/src/gestures/scale.dart
index 83b996ae22d..bf5d9595741 100644
--- a/packages/flutter/lib/src/gestures/scale.dart
+++ b/packages/flutter/lib/src/gestures/scale.dart
@@ -338,7 +338,7 @@ class ScaleGestureRecognizer extends OneSequenceGestureRecognizer {
 
     // Compute the focal point
     Offset focalPoint = Offset.zero;
-    for (int pointer in _pointerLocations.keys)
+    for (final int pointer in _pointerLocations.keys)
       focalPoint += _pointerLocations[pointer];
     _currentFocalPoint = count > 0 ? focalPoint / count.toDouble() : Offset.zero;
 
@@ -348,7 +348,7 @@ class ScaleGestureRecognizer extends OneSequenceGestureRecognizer {
     double totalDeviation = 0.0;
     double totalHorizontalDeviation = 0.0;
     double totalVerticalDeviation = 0.0;
-    for (int pointer in _pointerLocations.keys) {
+    for (final int pointer in _pointerLocations.keys) {
       totalDeviation += (_currentFocalPoint - _pointerLocations[pointer]).distance;
       totalHorizontalDeviation += (_currentFocalPoint.dx - _pointerLocations[pointer].dx).abs();
       totalVerticalDeviation += (_currentFocalPoint.dy - _pointerLocations[pointer].dy).abs();
diff --git a/packages/flutter/lib/src/gestures/team.dart b/packages/flutter/lib/src/gestures/team.dart
index 2dcdd738a58..128a323ec3e 100644
--- a/packages/flutter/lib/src/gestures/team.dart
+++ b/packages/flutter/lib/src/gestures/team.dart
@@ -34,7 +34,7 @@ class _CombiningGestureArenaMember extends GestureArenaMember {
     assert(_winner != null || _members.isNotEmpty);
     _close();
     _winner ??= _owner.captain ?? _members[0];
-    for (GestureArenaMember member in _members) {
+    for (final GestureArenaMember member in _members) {
       if (member != _winner)
         member.rejectGesture(pointer);
     }
@@ -45,7 +45,7 @@ class _CombiningGestureArenaMember extends GestureArenaMember {
   void rejectGesture(int pointer) {
     assert(_pointer == pointer);
     _close();
-    for (GestureArenaMember member in _members)
+    for (final GestureArenaMember member in _members)
       member.rejectGesture(pointer);
   }
 
diff --git a/packages/flutter/lib/src/material/about.dart b/packages/flutter/lib/src/material/about.dart
index 55e7e58d332..44fc5397f8a 100644
--- a/packages/flutter/lib/src/material/about.dart
+++ b/packages/flutter/lib/src/material/about.dart
@@ -488,7 +488,7 @@ class _LicensePageState extends State<LicensePage> {
       debugFlowId = flow.id;
       return true;
     }());
-    await for (LicenseEntry license in LicenseRegistry.licenses) {
+    await for (final LicenseEntry license in LicenseRegistry.licenses) {
       if (!mounted) {
         return;
       }
@@ -523,7 +523,7 @@ class _LicensePageState extends State<LicensePage> {
             textAlign: TextAlign.center,
           ),
         ));
-        for (LicenseParagraph paragraph in paragraphs) {
+        for (final LicenseParagraph paragraph in paragraphs) {
           if (paragraph.indent == LicenseParagraph.centeredIndent) {
             _licenses.add(Padding(
               padding: const EdgeInsets.only(top: 16.0),
diff --git a/packages/flutter/lib/src/material/animated_icons/animated_icons.dart b/packages/flutter/lib/src/material/animated_icons/animated_icons.dart
index 4c7d9b1d264..97366e44cbd 100644
--- a/packages/flutter/lib/src/material/animated_icons/animated_icons.dart
+++ b/packages/flutter/lib/src/material/animated_icons/animated_icons.dart
@@ -162,7 +162,7 @@ class _AnimatedIconPainter extends CustomPainter {
     }
 
     final double clampedProgress = progress.value.clamp(0.0, 1.0) as double;
-    for (_PathFrames path in paths)
+    for (final _PathFrames path in paths)
       path.paint(canvas, color, uiPathFactory, clampedProgress);
   }
 
@@ -203,7 +203,7 @@ class _PathFrames {
       ..style = PaintingStyle.fill
       ..color = color.withOpacity(color.opacity * opacity);
     final ui.Path path = uiPathFactory();
-    for (_PathCommand command in commands)
+    for (final _PathCommand command in commands)
       command.apply(path, progress);
     canvas.drawPath(path, paint);
   }
diff --git a/packages/flutter/lib/src/material/arc.dart b/packages/flutter/lib/src/material/arc.dart
index b6bf4ab7d40..94ddec00129 100644
--- a/packages/flutter/lib/src/material/arc.dart
+++ b/packages/flutter/lib/src/material/arc.dart
@@ -199,7 +199,7 @@ typedef _KeyFunc<T> = double Function(T input);
 T _maxBy<T>(Iterable<T> input, _KeyFunc<T> keyFunc) {
   T maxValue;
   double maxKey;
-  for (T value in input) {
+  for (final T value in input) {
     final double key = keyFunc(value);
     if (maxKey == null || key > maxKey) {
       maxValue = value;
diff --git a/packages/flutter/lib/src/material/bottom_navigation_bar.dart b/packages/flutter/lib/src/material/bottom_navigation_bar.dart
index 9ea673d5902..2b6856765e6 100644
--- a/packages/flutter/lib/src/material/bottom_navigation_bar.dart
+++ b/packages/flutter/lib/src/material/bottom_navigation_bar.dart
@@ -670,9 +670,9 @@ class _BottomNavigationBarState extends State<BottomNavigationBar> with TickerPr
   static final Animatable<double> _flexTween = Tween<double>(begin: 1.0, end: 1.5);
 
   void _resetState() {
-    for (AnimationController controller in _controllers)
+    for (final AnimationController controller in _controllers)
       controller.dispose();
-    for (_Circle circle in _circles)
+    for (final _Circle circle in _circles)
       circle.dispose();
     _circles.clear();
 
@@ -708,9 +708,9 @@ class _BottomNavigationBarState extends State<BottomNavigationBar> with TickerPr
 
   @override
   void dispose() {
-    for (AnimationController controller in _controllers)
+    for (final AnimationController controller in _controllers)
       controller.dispose();
-    for (_Circle circle in _circles)
+    for (final _Circle circle in _circles)
       circle.dispose();
     super.dispose();
   }
@@ -984,7 +984,7 @@ class _RadialPainter extends CustomPainter {
 
   @override
   void paint(Canvas canvas, Size size) {
-    for (_Circle circle in circles) {
+    for (final _Circle circle in circles) {
       final Paint paint = Paint()..color = circle.color;
       final Rect rect = Rect.fromLTWH(0.0, 0.0, size.width, size.height);
       canvas.clipRect(rect);
diff --git a/packages/flutter/lib/src/material/chip.dart b/packages/flutter/lib/src/material/chip.dart
index 85b0e355612..9ac390e3ac4 100644
--- a/packages/flutter/lib/src/material/chip.dart
+++ b/packages/flutter/lib/src/material/chip.dart
@@ -216,7 +216,7 @@ abstract class DeletableChipAttributes {
   ///   ];
   ///
   ///   Iterable<Widget> get actorWidgets sync* {
-  ///     for (Actor actor in _cast) {
+  ///     for (final Actor actor in _cast) {
   ///       yield Padding(
   ///         padding: const EdgeInsets.all(4.0),
   ///         child: Chip(
@@ -1056,7 +1056,7 @@ class ChoiceChip extends StatelessWidget
 ///   List<String> _filters = <String>[];
 ///
 ///   Iterable<Widget> get actorWidgets sync* {
-///     for (ActorFilterEntry actor in _cast) {
+///     for (final ActorFilterEntry actor in _cast) {
 ///       yield Padding(
 ///         padding: const EdgeInsets.all(4.0),
 ///         child: FilterChip(
@@ -2316,7 +2316,7 @@ class _RenderChip extends RenderBox {
   @override
   void attach(PipelineOwner owner) {
     super.attach(owner);
-    for (RenderBox child in _children) {
+    for (final RenderBox child in _children) {
       child.attach(owner);
     }
   }
@@ -2324,7 +2324,7 @@ class _RenderChip extends RenderBox {
   @override
   void detach() {
     super.detach();
-    for (RenderBox child in _children) {
+    for (final RenderBox child in _children) {
       child.detach();
     }
   }
diff --git a/packages/flutter/lib/src/material/data_table.dart b/packages/flutter/lib/src/material/data_table.dart
index 3f87bfcd402..b224aa121c3 100644
--- a/packages/flutter/lib/src/material/data_table.dart
+++ b/packages/flutter/lib/src/material/data_table.dart
@@ -454,7 +454,7 @@ class DataTable extends StatelessWidget {
     if (onSelectAll != null) {
       onSelectAll(checked);
     } else {
-      for (DataRow row in rows) {
+      for (final DataRow row in rows) {
         if ((row.onSelectChanged != null) && (row.selected != checked))
           row.onSelectChanged(checked);
       }
@@ -648,7 +648,7 @@ class DataTable extends StatelessWidget {
         onCheckboxChanged: _handleSelectAll,
       );
       rowIndex = 1;
-      for (DataRow row in rows) {
+      for (final DataRow row in rows) {
         tableRows[rowIndex].children[0] = _buildCheckbox(
           color: theme.accentColor,
           checked: row.selected,
@@ -699,7 +699,7 @@ class DataTable extends StatelessWidget {
         ascending: sortAscending,
       );
       rowIndex = 1;
-      for (DataRow row in rows) {
+      for (final DataRow row in rows) {
         final DataCell cell = row.cells[dataColumnIndex];
         tableRows[rowIndex].children[displayColumnIndex] = _buildDataCell(
           context: context,
diff --git a/packages/flutter/lib/src/material/expansion_panel.dart b/packages/flutter/lib/src/material/expansion_panel.dart
index 6a8df6b1e36..3f56eb48e72 100644
--- a/packages/flutter/lib/src/material/expansion_panel.dart
+++ b/packages/flutter/lib/src/material/expansion_panel.dart
@@ -389,7 +389,7 @@ class _ExpansionPanelListState extends State<ExpansionPanelList> {
 
   bool _allIdentifiersUnique() {
     final Map<Object, bool> identifierMap = <Object, bool>{};
-    for (ExpansionPanelRadio child in widget.children.cast<ExpansionPanelRadio>()) {
+    for (final ExpansionPanelRadio child in widget.children.cast<ExpansionPanelRadio>()) {
       identifierMap[child.value] = true;
     }
     return identifierMap.length == widget.children.length;
@@ -427,7 +427,7 @@ class _ExpansionPanelListState extends State<ExpansionPanelList> {
   }
 
   ExpansionPanelRadio searchPanelByValue(List<ExpansionPanelRadio> panels, Object value)  {
-    for (ExpansionPanelRadio panel in panels) {
+    for (final ExpansionPanelRadio panel in panels) {
       if (panel.value == value)
         return panel;
     }
diff --git a/packages/flutter/lib/src/material/ink_well.dart b/packages/flutter/lib/src/material/ink_well.dart
index 647484218cb..4fb38dbbac1 100644
--- a/packages/flutter/lib/src/material/ink_well.dart
+++ b/packages/flutter/lib/src/material/ink_well.dart
@@ -737,12 +737,12 @@ class _InkResponseState<T extends InkResponse> extends State<T> with AutomaticKe
     if (_splashes != null) {
       final Set<InteractiveInkFeature> splashes = _splashes;
       _splashes = null;
-      for (InteractiveInkFeature splash in splashes)
+      for (final InteractiveInkFeature splash in splashes)
         splash.dispose();
       _currentSplash = null;
     }
     assert(_currentSplash == null);
-    for (_HighlightType highlight in _highlights.keys) {
+    for (final _HighlightType highlight in _highlights.keys) {
       _highlights[highlight]?.dispose();
       _highlights[highlight] = null;
     }
@@ -768,7 +768,7 @@ class _InkResponseState<T extends InkResponse> extends State<T> with AutomaticKe
   Widget build(BuildContext context) {
     assert(widget.debugCheckContext(context));
     super.build(context); // See AutomaticKeepAliveClientMixin.
-    for (_HighlightType type in _highlights.keys) {
+    for (final _HighlightType type in _highlights.keys) {
       _highlights[type]?.color = getHighlightColorForType(type);
     }
     _currentSplash?.color = widget.splashColor ?? Theme.of(context).splashColor;
diff --git a/packages/flutter/lib/src/material/input_decorator.dart b/packages/flutter/lib/src/material/input_decorator.dart
index 1ce7920716b..e868c6a69ef 100644
--- a/packages/flutter/lib/src/material/input_decorator.dart
+++ b/packages/flutter/lib/src/material/input_decorator.dart
@@ -805,14 +805,14 @@ class _RenderDecoration extends RenderBox {
   @override
   void attach(PipelineOwner owner) {
     super.attach(owner);
-    for (RenderBox child in _children)
+    for (final RenderBox child in _children)
       child.attach(owner);
   }
 
   @override
   void detach() {
     super.detach();
-    for (RenderBox child in _children)
+    for (final RenderBox child in _children)
       child.detach();
   }
 
@@ -1199,7 +1199,7 @@ class _RenderDecoration extends RenderBox {
 
   double _lineHeight(double width, List<RenderBox> boxes) {
     double height = 0.0;
-    for (RenderBox box in boxes) {
+    for (final RenderBox box in boxes) {
       if (box == null)
         continue;
       height = math.max(_minHeight(box, width), height);
@@ -1448,7 +1448,7 @@ class _RenderDecoration extends RenderBox {
   @override
   bool hitTestChildren(BoxHitTestResult result, { @required Offset position }) {
     assert(position != null);
-    for (RenderBox child in _children) {
+    for (final RenderBox child in _children) {
       // TODO(hansmuller): label must be handled specially since we've transformed it
       final Offset offset = _boxParentData(child).offset;
       final bool isHit = result.addWithPaintOffset(
diff --git a/packages/flutter/lib/src/material/list_tile.dart b/packages/flutter/lib/src/material/list_tile.dart
index 93836a277b6..80eadc38d62 100644
--- a/packages/flutter/lib/src/material/list_tile.dart
+++ b/packages/flutter/lib/src/material/list_tile.dart
@@ -1209,14 +1209,14 @@ class _RenderListTile extends RenderBox {
   @override
   void attach(PipelineOwner owner) {
     super.attach(owner);
-    for (RenderBox child in _children)
+    for (final RenderBox child in _children)
       child.attach(owner);
   }
 
   @override
   void detach() {
     super.detach();
-    for (RenderBox child in _children)
+    for (final RenderBox child in _children)
       child.detach();
   }
 
@@ -1479,7 +1479,7 @@ class _RenderListTile extends RenderBox {
   @override
   bool hitTestChildren(BoxHitTestResult result, { @required Offset position }) {
     assert(position != null);
-    for (RenderBox child in _children) {
+    for (final RenderBox child in _children) {
       final BoxParentData parentData = child.parentData as BoxParentData;
       final bool isHit = result.addWithPaintOffset(
         offset: parentData.offset,
diff --git a/packages/flutter/lib/src/material/material.dart b/packages/flutter/lib/src/material/material.dart
index 679542476b1..39f3d2aad59 100644
--- a/packages/flutter/lib/src/material/material.dart
+++ b/packages/flutter/lib/src/material/material.dart
@@ -524,7 +524,7 @@ class _RenderInkFeatures extends RenderProxyBox implements MaterialInkController
       canvas.save();
       canvas.translate(offset.dx, offset.dy);
       canvas.clipRect(Offset.zero & size);
-      for (InkFeature inkFeature in _inkFeatures)
+      for (final InkFeature inkFeature in _inkFeatures)
         inkFeature._paint(canvas);
       canvas.restore();
     }
diff --git a/packages/flutter/lib/src/material/mergeable_material.dart b/packages/flutter/lib/src/material/mergeable_material.dart
index b87251f193a..e60d5fabf6e 100644
--- a/packages/flutter/lib/src/material/mergeable_material.dart
+++ b/packages/flutter/lib/src/material/mergeable_material.dart
@@ -204,7 +204,7 @@ class _MergeableMaterialState extends State<MergeableMaterial> with TickerProvid
 
   @override
   void dispose() {
-    for (MergeableMaterialItem child in _children) {
+    for (final MergeableMaterialItem child in _children) {
       if (child is MaterialGap)
         _animationTuples[child.key].controller.dispose();
     }
@@ -687,7 +687,7 @@ class _RenderMergeableMaterialListBody extends RenderListBody {
   List<BoxShadow> boxShadows;
 
   void _paintShadows(Canvas canvas, Rect rect) {
-    for (BoxShadow boxShadow in boxShadows) {
+    for (final BoxShadow boxShadow in boxShadows) {
       final Paint paint = boxShadow.toPaint();
       // TODO(dragostis): Right now, we are only interpolating the border radii
       // of the visible Material slices, not the shadows; they are not getting
diff --git a/packages/flutter/lib/src/material/scaffold.dart b/packages/flutter/lib/src/material/scaffold.dart
index 5a3f2c76dbf..e1b86781f3a 100644
--- a/packages/flutter/lib/src/material/scaffold.dart
+++ b/packages/flutter/lib/src/material/scaffold.dart
@@ -2113,7 +2113,7 @@ class ScaffoldState extends State<Scaffold> with TickerProviderStateMixin {
     _snackBarTimer?.cancel();
     _snackBarTimer = null;
     _geometryNotifier.dispose();
-    for (_StandardBottomSheet bottomSheet in _dismissedBottomSheets) {
+    for (final _StandardBottomSheet bottomSheet in _dismissedBottomSheets) {
       bottomSheet.animationController?.dispose();
     }
     if (_currentBottomSheet != null) {
diff --git a/packages/flutter/lib/src/material/tabs.dart b/packages/flutter/lib/src/material/tabs.dart
index cc159d04aa7..740c08530fa 100644
--- a/packages/flutter/lib/src/material/tabs.dart
+++ b/packages/flutter/lib/src/material/tabs.dart
@@ -750,7 +750,7 @@ class TabBar extends StatefulWidget implements PreferredSizeWidget {
   /// [AppBar] uses this size to compute its own preferred size.
   @override
   Size get preferredSize {
-    for (Widget item in tabs) {
+    for (final Widget item in tabs) {
       if (item is Tab) {
         final Tab tab = item;
         if (tab.text != null && tab.icon != null)
diff --git a/packages/flutter/lib/src/material/time_picker.dart b/packages/flutter/lib/src/material/time_picker.dart
index b02f6917a1f..d6ddd703035 100644
--- a/packages/flutter/lib/src/material/time_picker.dart
+++ b/packages/flutter/lib/src/material/time_picker.dart
@@ -685,7 +685,7 @@ class _TimePickerHeaderLayout extends MultiChildLayoutDelegate {
 
   void _positionPivoted(double width, double y, Map<_TimePickerHeaderId, Size> childSizes, List<_TimePickerHeaderFragment> fragments, int pivotIndex) {
     double tailWidth = childSizes[fragments[pivotIndex].layoutId].width / 2.0;
-    for (_TimePickerHeaderFragment fragment in fragments.skip(pivotIndex + 1)) {
+    for (final _TimePickerHeaderFragment fragment in fragments.skip(pivotIndex + 1)) {
       tailWidth += childSizes[fragment.layoutId].width + fragment.startMargin;
     }
 
@@ -703,7 +703,7 @@ class _TimePickerHeaderLayout extends MultiChildLayoutDelegate {
   void _positionPiece(double width, double centeredAroundY, Map<_TimePickerHeaderId, Size> childSizes, List<_TimePickerHeaderFragment> fragments) {
     double pieceWidth = 0.0;
     double nextMargin = 0.0;
-    for (_TimePickerHeaderFragment fragment in fragments) {
+    for (final _TimePickerHeaderFragment fragment in fragments) {
       final Size childSize = childSizes[fragment.layoutId];
       pieceWidth += childSize.width + nextMargin;
       // Delay application of margin until next element because margin of the
@@ -927,7 +927,7 @@ class _DialPainter extends CustomPainter {
       final double labelThetaIncrement = -_kTwoPi / labels.length;
       double labelTheta = math.pi / 2.0;
 
-      for (_TappableLabel label in labels) {
+      for (final _TappableLabel label in labels) {
         final TextPainter labelPainter = label.painter;
         final Offset labelOffset = Offset(-labelPainter.width / 2.0, -labelPainter.height / 2.0);
         labelPainter.paint(canvas, getOffsetForTheta(labelTheta, ring) + labelOffset);
@@ -1339,7 +1339,7 @@ class _DialState extends State<_Dial> with SingleTickerProviderStateMixin {
   }
 
   List<_TappableLabel> _build24HourInnerRing(TextTheme textTheme) => <_TappableLabel>[
-    for (TimeOfDay timeOfDay in _amHours)
+    for (final TimeOfDay timeOfDay in _amHours)
       _buildTappableLabel(
         textTheme,
         timeOfDay.hour,
@@ -1351,7 +1351,7 @@ class _DialState extends State<_Dial> with SingleTickerProviderStateMixin {
   ];
 
   List<_TappableLabel> _build24HourOuterRing(TextTheme textTheme) => <_TappableLabel>[
-    for (TimeOfDay timeOfDay in _pmHours)
+    for (final TimeOfDay timeOfDay in _pmHours)
       _buildTappableLabel(
         textTheme,
         timeOfDay.hour,
@@ -1363,7 +1363,7 @@ class _DialState extends State<_Dial> with SingleTickerProviderStateMixin {
   ];
 
   List<_TappableLabel> _build12HourOuterRing(TextTheme textTheme) => <_TappableLabel>[
-    for (TimeOfDay timeOfDay in _amHours)
+    for (final TimeOfDay timeOfDay in _amHours)
       _buildTappableLabel(
         textTheme,
         timeOfDay.hour,
@@ -1391,7 +1391,7 @@ class _DialState extends State<_Dial> with SingleTickerProviderStateMixin {
     ];
 
     return <_TappableLabel>[
-      for (TimeOfDay timeOfDay in _minuteMarkerValues)
+      for (final TimeOfDay timeOfDay in _minuteMarkerValues)
         _buildTappableLabel(
           textTheme,
           timeOfDay.minute,
diff --git a/packages/flutter/lib/src/painting/binding.dart b/packages/flutter/lib/src/painting/binding.dart
index 8adac804f89..cbdb882dbca 100644
--- a/packages/flutter/lib/src/painting/binding.dart
+++ b/packages/flutter/lib/src/painting/binding.dart
@@ -128,7 +128,7 @@ class _SystemFontsNotifier extends Listenable {
   final Set<VoidCallback> _systemFontsCallbacks = <VoidCallback>{};
 
   void notifyListeners () {
-    for (VoidCallback callback in _systemFontsCallbacks) {
+    for (final VoidCallback callback in _systemFontsCallbacks) {
       callback();
     }
   }
diff --git a/packages/flutter/lib/src/painting/borders.dart b/packages/flutter/lib/src/painting/borders.dart
index 5725e3e3816..f5517c89a81 100644
--- a/packages/flutter/lib/src/painting/borders.dart
+++ b/packages/flutter/lib/src/painting/borders.dart
@@ -603,7 +603,7 @@ class _CompoundBorder extends ShapeBorder {
 
   @override
   void paint(Canvas canvas, Rect rect, { TextDirection textDirection }) {
-    for (ShapeBorder border in borders) {
+    for (final ShapeBorder border in borders) {
       border.paint(canvas, rect, textDirection: textDirection);
       rect = border.dimensions.resolve(textDirection).deflateRect(rect);
     }
diff --git a/packages/flutter/lib/src/painting/box_decoration.dart b/packages/flutter/lib/src/painting/box_decoration.dart
index bb3b7b43530..95ec70f3f4c 100644
--- a/packages/flutter/lib/src/painting/box_decoration.dart
+++ b/packages/flutter/lib/src/painting/box_decoration.dart
@@ -433,7 +433,7 @@ class _BoxDecorationPainter extends BoxPainter {
   void _paintShadows(Canvas canvas, Rect rect, TextDirection textDirection) {
     if (_decoration.boxShadow == null)
       return;
-    for (BoxShadow boxShadow in _decoration.boxShadow) {
+    for (final BoxShadow boxShadow in _decoration.boxShadow) {
       final Paint paint = boxShadow.toPaint();
       final Rect bounds = rect.shift(boxShadow.offset).inflate(boxShadow.spreadRadius);
       _paintBox(canvas, bounds, paint, textDirection);
diff --git a/packages/flutter/lib/src/painting/decoration_image.dart b/packages/flutter/lib/src/painting/decoration_image.dart
index 69b35971635..e7dfe173c71 100644
--- a/packages/flutter/lib/src/painting/decoration_image.dart
+++ b/packages/flutter/lib/src/painting/decoration_image.dart
@@ -443,14 +443,14 @@ void paintImage({
     if (repeat == ImageRepeat.noRepeat) {
       canvas.drawImageRect(image, sourceRect, destinationRect, paint);
     } else {
-      for (Rect tileRect in _generateImageTileRects(rect, destinationRect, repeat))
+      for (final Rect tileRect in _generateImageTileRects(rect, destinationRect, repeat))
         canvas.drawImageRect(image, sourceRect, tileRect, paint);
     }
   } else {
     if (repeat == ImageRepeat.noRepeat) {
       canvas.drawImageNine(image, centerSlice, destinationRect, paint);
     } else {
-      for (Rect tileRect in _generateImageTileRects(rect, destinationRect, repeat))
+      for (final Rect tileRect in _generateImageTileRects(rect, destinationRect, repeat))
         canvas.drawImageNine(image, centerSlice, tileRect, paint);
     }
   }
diff --git a/packages/flutter/lib/src/painting/image_resolution.dart b/packages/flutter/lib/src/painting/image_resolution.dart
index fcc0bd7179f..17e6eb811ec 100644
--- a/packages/flutter/lib/src/painting/image_resolution.dart
+++ b/packages/flutter/lib/src/painting/image_resolution.dart
@@ -233,7 +233,7 @@ class AssetImage extends AssetBundleImageProvider {
       return main;
     // TODO(ianh): Consider moving this parsing logic into _manifestParser.
     final SplayTreeMap<double, String> mapping = SplayTreeMap<double, String>();
-    for (String candidate in candidates)
+    for (final String candidate in candidates)
       mapping[_parseScale(candidate)] = candidate;
     // TODO(ianh): implement support for config.locale, config.textDirection,
     // config.size, config.platform (then document this over in the Image.asset
diff --git a/packages/flutter/lib/src/painting/image_stream.dart b/packages/flutter/lib/src/painting/image_stream.dart
index 82e62a773d9..4b062f99c03 100644
--- a/packages/flutter/lib/src/painting/image_stream.dart
+++ b/packages/flutter/lib/src/painting/image_stream.dart
@@ -402,7 +402,7 @@ abstract class ImageStreamCompleter extends Diagnosticable {
     // Make a copy to allow for concurrent modification.
     final List<ImageStreamListener> localListeners =
         List<ImageStreamListener>.from(_listeners);
-    for (ImageStreamListener listener in localListeners) {
+    for (final ImageStreamListener listener in localListeners) {
       try {
         listener.onImage(image, false);
       } catch (exception, stack) {
@@ -469,7 +469,7 @@ abstract class ImageStreamCompleter extends Diagnosticable {
     if (localErrorListeners.isEmpty) {
       FlutterError.reportError(_currentError);
     } else {
-      for (ImageErrorListener errorListener in localErrorListeners) {
+      for (final ImageErrorListener errorListener in localErrorListeners) {
         try {
           errorListener(exception, stack);
         } catch (exception, stack) {
@@ -604,7 +604,7 @@ class MultiFrameImageStreamCompleter extends ImageStreamCompleter {
                 .map<ImageChunkListener>((ImageStreamListener listener) => listener.onChunk)
                 .where((ImageChunkListener chunkListener) => chunkListener != null)
                 .toList();
-            for (ImageChunkListener listener in localListeners) {
+            for (final ImageChunkListener listener in localListeners) {
               listener(event);
             }
           }
diff --git a/packages/flutter/lib/src/painting/shader_warm_up.dart b/packages/flutter/lib/src/painting/shader_warm_up.dart
index 608534f1ced..420f334588c 100644
--- a/packages/flutter/lib/src/painting/shader_warm_up.dart
+++ b/packages/flutter/lib/src/painting/shader_warm_up.dart
@@ -171,7 +171,7 @@ class DefaultShaderWarmUp extends ShaderWarmUp {
     // Warm up path stroke and fill shaders.
     for (int i = 0; i < paths.length; i += 1) {
       canvas.save();
-      for (ui.Paint paint in paints) {
+      for (final ui.Paint paint in paints) {
         canvas.drawPath(paths[i], paint);
         canvas.translate(drawCallSpacing, 0.0);
       }
@@ -202,7 +202,7 @@ class DefaultShaderWarmUp extends ShaderWarmUp {
     //
     // Add an integral or fractional translation to trigger Skia's non-AA or AA
     // optimizations (as did before in normal FillRectOp in rrect clip cases).
-    for (double fraction in <double>[0.0, 0.5]) {
+    for (final double fraction in <double>[0.0, 0.5]) {
       canvas
         ..save()
         ..translate(fraction, fraction)
diff --git a/packages/flutter/lib/src/painting/text_span.dart b/packages/flutter/lib/src/painting/text_span.dart
index 93d49d02a05..d4ea24918a8 100644
--- a/packages/flutter/lib/src/painting/text_span.dart
+++ b/packages/flutter/lib/src/painting/text_span.dart
@@ -206,7 +206,7 @@ class TextSpan extends InlineSpan {
     if (text != null)
       builder.addText(text);
     if (children != null) {
-      for (InlineSpan child in children) {
+      for (final InlineSpan child in children) {
         assert(child != null);
         child.build(
           builder,
@@ -231,7 +231,7 @@ class TextSpan extends InlineSpan {
         return false;
     }
     if (children != null) {
-      for (InlineSpan child in children) {
+      for (final InlineSpan child in children) {
         if (!child.visitChildren(visitor))
           return false;
       }
@@ -256,7 +256,7 @@ class TextSpan extends InlineSpan {
         return false;
     }
     if (children != null) {
-      for (InlineSpan child in children) {
+      for (final InlineSpan child in children) {
         assert(
           child is TextSpan,
           'visitTextSpan is deprecated. Use visitChildren to support InlineSpans',
@@ -300,7 +300,7 @@ class TextSpan extends InlineSpan {
       buffer.write(text);
     }
     if (children != null) {
-      for (InlineSpan child in children) {
+      for (final InlineSpan child in children) {
         child.computeToPlainText(buffer,
           includeSemanticsLabels: includeSemanticsLabels,
           includePlaceholders: includePlaceholders,
@@ -320,7 +320,7 @@ class TextSpan extends InlineSpan {
       ));
     }
     if (children != null) {
-      for (InlineSpan child in children) {
+      for (final InlineSpan child in children) {
         child.computeSemanticsInformation(collector);
       }
     }
@@ -364,7 +364,7 @@ class TextSpan extends InlineSpan {
   bool debugAssertIsValid() {
     assert(() {
       if (children != null) {
-        for (InlineSpan child in children) {
+        for (final InlineSpan child in children) {
           if (child == null) {
             throw FlutterError.fromParts(<DiagnosticsNode>[
               ErrorSummary('TextSpan contains a null child.'),
diff --git a/packages/flutter/lib/src/rendering/custom_paint.dart b/packages/flutter/lib/src/rendering/custom_paint.dart
index 59ed8cdbd13..e3cc975a91d 100644
--- a/packages/flutter/lib/src/rendering/custom_paint.dart
+++ b/packages/flutter/lib/src/rendering/custom_paint.dart
@@ -790,7 +790,7 @@ class RenderCustomPaint extends RenderProxyBox {
     }
 
     assert(() {
-      for (SemanticsNode node in newChildren) {
+      for (final SemanticsNode node in newChildren) {
         assert(node != null);
       }
       return true;
diff --git a/packages/flutter/lib/src/rendering/debug_overflow_indicator.dart b/packages/flutter/lib/src/rendering/debug_overflow_indicator.dart
index 7911b0a0a31..8ec25e13041 100644
--- a/packages/flutter/lib/src/rendering/debug_overflow_indicator.dart
+++ b/packages/flutter/lib/src/rendering/debug_overflow_indicator.dart
@@ -282,7 +282,7 @@ mixin DebugOverflowIndicatorMixin on RenderObject {
     }
 
     final List<_OverflowRegionData> overflowRegions = _calculateOverflowRegions(overflow, containerRect);
-    for (_OverflowRegionData region in overflowRegions) {
+    for (final _OverflowRegionData region in overflowRegions) {
       context.canvas.drawRect(region.rect.shift(offset), _indicatorPaint);
       final TextSpan textSpan = _indicatorLabel[region.side.index].text as TextSpan;
       if (textSpan?.text != region.label) {
diff --git a/packages/flutter/lib/src/rendering/editable.dart b/packages/flutter/lib/src/rendering/editable.dart
index 79765ba981f..1b89c0e7830 100644
--- a/packages/flutter/lib/src/rendering/editable.dart
+++ b/packages/flutter/lib/src/rendering/editable.dart
@@ -1908,7 +1908,7 @@ class RenderEditable extends RenderBox with RelayoutWhenSystemFontsChangeMixin {
       'Last width ($_textLayoutLastMinWidth, $_textLayoutLastMaxWidth) not the same as max width constraint (${constraints.minWidth}, ${constraints.maxWidth}).');
     assert(_selectionRects != null);
     final Paint paint = Paint()..color = _selectionColor;
-    for (ui.TextBox box in _selectionRects)
+    for (final ui.TextBox box in _selectionRects)
       canvas.drawRect(box.toRect().shift(effectiveOffset), paint);
   }
 
diff --git a/packages/flutter/lib/src/rendering/flow.dart b/packages/flutter/lib/src/rendering/flow.dart
index b2a7d458a57..533e5d890f0 100644
--- a/packages/flutter/lib/src/rendering/flow.dart
+++ b/packages/flutter/lib/src/rendering/flow.dart
@@ -352,7 +352,7 @@ class RenderFlow extends RenderBox
     _lastPaintOrder.clear();
     _paintingContext = context;
     _paintingOffset = offset;
-    for (RenderBox child in _randomAccessChildren) {
+    for (final RenderBox child in _randomAccessChildren) {
       final FlowParentData childParentData = child.parentData as FlowParentData;
       childParentData._transform = null;
     }
diff --git a/packages/flutter/lib/src/rendering/layer.dart b/packages/flutter/lib/src/rendering/layer.dart
index 4a32715465b..5b4f2730358 100644
--- a/packages/flutter/lib/src/rendering/layer.dart
+++ b/packages/flutter/lib/src/rendering/layer.dart
@@ -70,7 +70,7 @@ class AnnotationResult<T> {
   ///
   /// It is similar to [entries] but does not contain other information.
   Iterable<T> get annotations sync* {
-    for (AnnotationEntry<T> entry in _entries)
+    for (final AnnotationEntry<T> entry in _entries)
       yield entry.annotation;
   }
 }
@@ -804,7 +804,7 @@ class ContainerLayer extends Layer {
       // PhysicalModelLayers. If we don't, we'll end up adding duplicate layers
       // or continuing to render stale outlines.
       if (temporaryLayers != null) {
-        for (PictureLayer temporaryLayer in temporaryLayers) {
+        for (final PictureLayer temporaryLayer in temporaryLayers) {
           temporaryLayer.remove();
         }
       }
diff --git a/packages/flutter/lib/src/rendering/object.dart b/packages/flutter/lib/src/rendering/object.dart
index 1da7a3bed36..3476119123e 100644
--- a/packages/flutter/lib/src/rendering/object.dart
+++ b/packages/flutter/lib/src/rendering/object.dart
@@ -883,7 +883,7 @@ class PipelineOwner {
       while (_nodesNeedingLayout.isNotEmpty) {
         final List<RenderObject> dirtyNodes = _nodesNeedingLayout;
         _nodesNeedingLayout = <RenderObject>[];
-        for (RenderObject node in dirtyNodes..sort((RenderObject a, RenderObject b) => a.depth - b.depth)) {
+        for (final RenderObject node in dirtyNodes..sort((RenderObject a, RenderObject b) => a.depth - b.depth)) {
           if (node._needsLayout && node.owner == this)
             node._layoutWithoutResize();
         }
@@ -935,7 +935,7 @@ class PipelineOwner {
       Timeline.startSync('Compositing bits');
     }
     _nodesNeedingCompositingBitsUpdate.sort((RenderObject a, RenderObject b) => a.depth - b.depth);
-    for (RenderObject node in _nodesNeedingCompositingBitsUpdate) {
+    for (final RenderObject node in _nodesNeedingCompositingBitsUpdate) {
       if (node._needsCompositingBitsUpdate && node.owner == this)
         node._updateCompositingBits();
     }
@@ -974,7 +974,7 @@ class PipelineOwner {
       final List<RenderObject> dirtyNodes = _nodesNeedingPaint;
       _nodesNeedingPaint = <RenderObject>[];
       // Sort the dirty nodes in reverse order (deepest first).
-      for (RenderObject node in dirtyNodes..sort((RenderObject a, RenderObject b) => b.depth - a.depth)) {
+      for (final RenderObject node in dirtyNodes..sort((RenderObject a, RenderObject b) => b.depth - a.depth)) {
         assert(node._layer != null);
         if (node._needsPaint && node.owner == this) {
           if (node._layer.attached) {
@@ -1079,7 +1079,7 @@ class PipelineOwner {
       final List<RenderObject> nodesToProcess = _nodesNeedingSemantics.toList()
         ..sort((RenderObject a, RenderObject b) => a.depth - b.depth);
       _nodesNeedingSemantics.clear();
-      for (RenderObject node in nodesToProcess) {
+      for (final RenderObject node in nodesToProcess) {
         if (node._needsSemanticsUpdate && node.owner == this)
           node._updateSemantics();
       }
@@ -2625,7 +2625,7 @@ abstract class RenderObject extends AbstractNode with DiagnosticableTreeMixin im
           dropSemanticsOfPreviousSiblings = true;
       }
       // Figure out which child fragments are to be made explicit.
-      for (_InterestingSemanticsFragment fragment in parentFragment.interestingFragments) {
+      for (final _InterestingSemanticsFragment fragment in parentFragment.interestingFragments) {
         fragments.add(fragment);
         fragment.addAncestor(this);
         fragment.addTags(config.tagsForChildren);
@@ -2637,7 +2637,7 @@ abstract class RenderObject extends AbstractNode with DiagnosticableTreeMixin im
           continue;
         if (!config.isCompatibleWith(fragment.config))
           toBeMarkedExplicit.add(fragment);
-        for (_InterestingSemanticsFragment siblingFragment in fragments.sublist(0, fragments.length - 1)) {
+        for (final _InterestingSemanticsFragment siblingFragment in fragments.sublist(0, fragments.length - 1)) {
           if (!fragment.config.isCompatibleWith(siblingFragment.config)) {
             toBeMarkedExplicit.add(fragment);
             toBeMarkedExplicit.add(siblingFragment);
@@ -2650,7 +2650,7 @@ abstract class RenderObject extends AbstractNode with DiagnosticableTreeMixin im
       return _AbortingSemanticsFragment(owner: this);
     }
 
-    for (_InterestingSemanticsFragment fragment in toBeMarkedExplicit)
+    for (final _InterestingSemanticsFragment fragment in toBeMarkedExplicit)
       fragment.markAsExplicit();
 
     _needsSemanticsUpdate = false;
@@ -3601,7 +3601,7 @@ class _SwitchableSemanticsFragment extends _InterestingSemanticsFragment {
   Iterable<SemanticsNode> compileChildren({ Rect parentSemanticsClipRect, Rect parentPaintClipRect, double elevationAdjustment }) sync* {
     if (!_isExplicit) {
       owner._semantics = null;
-      for (_InterestingSemanticsFragment fragment in _children) {
+      for (final _InterestingSemanticsFragment fragment in _children) {
         assert(_ancestorChain.first == fragment._ancestorChain.last);
         fragment._ancestorChain.addAll(_ancestorChain.sublist(1));
         yield* fragment.compileChildren(
@@ -3671,7 +3671,7 @@ class _SwitchableSemanticsFragment extends _InterestingSemanticsFragment {
 
   @override
   void addAll(Iterable<_InterestingSemanticsFragment> fragments) {
-    for (_InterestingSemanticsFragment fragment in fragments) {
+    for (final _InterestingSemanticsFragment fragment in fragments) {
       _children.add(fragment);
       if (fragment.config == null)
         continue;
diff --git a/packages/flutter/lib/src/rendering/paragraph.dart b/packages/flutter/lib/src/rendering/paragraph.dart
index b62cdd03e1d..5e9d800a994 100644
--- a/packages/flutter/lib/src/rendering/paragraph.dart
+++ b/packages/flutter/lib/src/rendering/paragraph.dart
@@ -333,7 +333,7 @@ class RenderParagraph extends RenderBox
   // alignments that require the baseline (baseline, aboveBaseline,
   // belowBaseline).
   bool _canComputeIntrinsics() {
-    for (PlaceholderSpan span in _placeholderSpans) {
+    for (final PlaceholderSpan span in _placeholderSpans) {
       switch (span.alignment) {
         case ui.PlaceholderAlignment.baseline:
         case ui.PlaceholderAlignment.aboveBaseline:
@@ -781,7 +781,7 @@ class RenderParagraph extends RenderBox
     final List<InlineSpanSemanticsInformation> combined = <InlineSpanSemanticsInformation>[];
     String workingText = '';
     String workingLabel;
-    for (InlineSpanSemanticsInformation info in _semanticsInfo) {
+    for (final InlineSpanSemanticsInformation info in _semanticsInfo) {
       if (info.requiresOwnNode) {
         if (workingText != null) {
           combined.add(InlineSpanSemanticsInformation(
@@ -823,7 +823,7 @@ class RenderParagraph extends RenderBox
       config.isSemanticBoundary = true;
     } else {
       final StringBuffer buffer = StringBuffer();
-      for (InlineSpanSemanticsInformation info in _semanticsInfo) {
+      for (final InlineSpanSemanticsInformation info in _semanticsInfo) {
         buffer.write(info.semanticsLabel ?? info.text);
       }
       config.label = buffer.toString();
@@ -841,7 +841,7 @@ class RenderParagraph extends RenderBox
     int start = 0;
     int placeholderIndex = 0;
     RenderBox child = firstChild;
-    for (InlineSpanSemanticsInformation info in _combineSemanticsInfo()) {
+    for (final InlineSpanSemanticsInformation info in _combineSemanticsInfo()) {
       final TextDirection initialDirection = currentDirection;
       final TextSelection selection = TextSelection(
         baseOffset: start,
@@ -853,7 +853,7 @@ class RenderParagraph extends RenderBox
       }
       Rect rect = rects.first.toRect();
       currentDirection = rects.first.direction;
-      for (ui.TextBox textBox in rects.skip(1)) {
+      for (final ui.TextBox textBox in rects.skip(1)) {
         rect = rect.expandToInclude(textBox.toRect());
         currentDirection = textBox.direction;
       }
diff --git a/packages/flutter/lib/src/rendering/platform_view.dart b/packages/flutter/lib/src/rendering/platform_view.dart
index 90d62fcfdf0..76f6835c970 100644
--- a/packages/flutter/lib/src/rendering/platform_view.dart
+++ b/packages/flutter/lib/src/rendering/platform_view.dart
@@ -417,7 +417,7 @@ class _UiKitViewGestureRecognizer extends OneSequenceGestureRecognizer {
   @override
   void addAllowedPointer(PointerDownEvent event) {
     startTrackingPointer(event.pointer, event.transform);
-    for (OneSequenceGestureRecognizer recognizer in _gestureRecognizers) {
+    for (final OneSequenceGestureRecognizer recognizer in _gestureRecognizers) {
       recognizer.addPointer(event);
     }
   }
@@ -493,7 +493,7 @@ class _PlatformViewGestureRecognizer extends OneSequenceGestureRecognizer {
   @override
   void addAllowedPointer(PointerDownEvent event) {
     startTrackingPointer(event.pointer, event.transform);
-    for (OneSequenceGestureRecognizer recognizer in _gestureRecognizers) {
+    for (final OneSequenceGestureRecognizer recognizer in _gestureRecognizers) {
       recognizer.addPointer(event);
     }
   }
diff --git a/packages/flutter/lib/src/rendering/sliver_multi_box_adaptor.dart b/packages/flutter/lib/src/rendering/sliver_multi_box_adaptor.dart
index becf10eeed9..037b342dcfe 100644
--- a/packages/flutter/lib/src/rendering/sliver_multi_box_adaptor.dart
+++ b/packages/flutter/lib/src/rendering/sliver_multi_box_adaptor.dart
@@ -375,14 +375,14 @@ abstract class RenderSliverMultiBoxAdaptor extends RenderSliver
   @override
   void attach(PipelineOwner owner) {
     super.attach(owner);
-    for (RenderBox child in _keepAliveBucket.values)
+    for (final RenderBox child in _keepAliveBucket.values)
       child.attach(owner);
   }
 
   @override
   void detach() {
     super.detach();
-    for (RenderBox child in _keepAliveBucket.values)
+    for (final RenderBox child in _keepAliveBucket.values)
       child.detach();
   }
 
@@ -683,7 +683,7 @@ abstract class RenderSliverMultiBoxAdaptor extends RenderSliver
     }
     if (_keepAliveBucket.isNotEmpty) {
       final List<int> indices = _keepAliveBucket.keys.toList()..sort();
-      for (int index in indices) {
+      for (final int index in indices) {
         children.add(_keepAliveBucket[index].toDiagnosticsNode(
           name: 'child with index $index (kept alive but not laid out)',
           style: DiagnosticsTreeStyle.offstage,
diff --git a/packages/flutter/lib/src/rendering/table.dart b/packages/flutter/lib/src/rendering/table.dart
index 12913ae3691..e0316f5aa19 100644
--- a/packages/flutter/lib/src/rendering/table.dart
+++ b/packages/flutter/lib/src/rendering/table.dart
@@ -96,7 +96,7 @@ class IntrinsicColumnWidth extends TableColumnWidth {
   @override
   double minIntrinsicWidth(Iterable<RenderBox> cells, double containerWidth) {
     double result = 0.0;
-    for (RenderBox cell in cells)
+    for (final RenderBox cell in cells)
       result = math.max(result, cell.getMinIntrinsicWidth(double.infinity));
     return result;
   }
@@ -104,7 +104,7 @@ class IntrinsicColumnWidth extends TableColumnWidth {
   @override
   double maxIntrinsicWidth(Iterable<RenderBox> cells, double containerWidth) {
     double result = 0.0;
-    for (RenderBox cell in cells)
+    for (final RenderBox cell in cells)
       result = math.max(result, cell.getMaxIntrinsicWidth(double.infinity));
     return result;
   }
@@ -527,7 +527,7 @@ class RenderTable extends RenderBox {
       return;
     _rowDecorations = value;
     if (_rowDecorationPainters != null) {
-      for (BoxPainter painter in _rowDecorationPainters)
+      for (final BoxPainter painter in _rowDecorationPainters)
         painter?.dispose();
     }
     _rowDecorationPainters = _rowDecorations != null ? List<BoxPainter>(_rowDecorations.length) : null;
@@ -592,7 +592,7 @@ class RenderTable extends RenderBox {
         assert(_rows == 0);
         return;
       }
-      for (RenderBox oldChild in _children) {
+      for (final RenderBox oldChild in _children) {
         if (oldChild != null)
           dropChild(oldChild);
       }
@@ -645,7 +645,7 @@ class RenderTable extends RenderBox {
       setFlatChildren(0, null);
       return;
     }
-    for (RenderBox oldChild in _children) {
+    for (final RenderBox oldChild in _children) {
       if (oldChild != null)
         dropChild(oldChild);
     }
@@ -664,7 +664,7 @@ class RenderTable extends RenderBox {
     assert(_children.length == rows * columns);
     _rows += 1;
     _children.addAll(cells);
-    for (RenderBox cell in cells) {
+    for (final RenderBox cell in cells) {
       if (cell != null)
         adoptChild(cell);
     }
@@ -695,7 +695,7 @@ class RenderTable extends RenderBox {
   @override
   void attach(PipelineOwner owner) {
     super.attach(owner);
-    for (RenderBox child in _children)
+    for (final RenderBox child in _children)
       child?.attach(owner);
   }
 
@@ -703,18 +703,18 @@ class RenderTable extends RenderBox {
   void detach() {
     super.detach();
     if (_rowDecorationPainters != null) {
-      for (BoxPainter painter in _rowDecorationPainters)
+      for (final BoxPainter painter in _rowDecorationPainters)
         painter?.dispose();
       _rowDecorationPainters = List<BoxPainter>(_rowDecorations.length);
     }
-    for (RenderBox child in _children)
+    for (final RenderBox child in _children)
       child?.detach();
   }
 
   @override
   void visitChildren(RenderObjectVisitor visitor) {
     assert(_children.length == rows * columns);
-    for (RenderBox child in _children) {
+    for (final RenderBox child in _children) {
       if (child != null)
         visitor(child);
     }
diff --git a/packages/flutter/lib/src/rendering/table_border.dart b/packages/flutter/lib/src/rendering/table_border.dart
index a277440f84f..7fa011862a5 100644
--- a/packages/flutter/lib/src/rendering/table_border.dart
+++ b/packages/flutter/lib/src/rendering/table_border.dart
@@ -226,7 +226,7 @@ class TableBorder {
               ..strokeWidth = verticalInside.width
               ..style = PaintingStyle.stroke;
             path.reset();
-            for (double x in columns) {
+            for (final double x in columns) {
               path.moveTo(rect.left + x, rect.top);
               path.lineTo(rect.left + x, rect.bottom);
             }
@@ -245,7 +245,7 @@ class TableBorder {
               ..strokeWidth = horizontalInside.width
               ..style = PaintingStyle.stroke;
             path.reset();
-            for (double y in rows) {
+            for (final double y in rows) {
               path.moveTo(rect.left, rect.top + y);
               path.lineTo(rect.right, rect.top + y);
             }
diff --git a/packages/flutter/lib/src/rendering/viewport.dart b/packages/flutter/lib/src/rendering/viewport.dart
index 7ce0996daef..809b3210d0e 100644
--- a/packages/flutter/lib/src/rendering/viewport.dart
+++ b/packages/flutter/lib/src/rendering/viewport.dart
@@ -581,7 +581,7 @@ abstract class RenderViewportBase<ParentDataClass extends ContainerParentDataMix
   }
 
   void _paintContents(PaintingContext context, Offset offset) {
-    for (RenderSliver child in childrenInPaintOrder) {
+    for (final RenderSliver child in childrenInPaintOrder) {
       if (child.geometry.visible)
         context.paintChild(child, offset + paintOffsetOf(child));
     }
@@ -631,7 +631,7 @@ abstract class RenderViewportBase<ParentDataClass extends ContainerParentDataMix
     assert(mainAxisPosition != null);
     assert(crossAxisPosition != null);
     final SliverHitTestResult sliverResult = SliverHitTestResult.wrap(result);
-    for (RenderSliver child in childrenInHitTestOrder) {
+    for (final RenderSliver child in childrenInHitTestOrder) {
       if (!child.geometry.visible) {
         continue;
       }
diff --git a/packages/flutter/lib/src/scheduler/binding.dart b/packages/flutter/lib/src/scheduler/binding.dart
index 17983c5db97..05ad7c5d111 100644
--- a/packages/flutter/lib/src/scheduler/binding.dart
+++ b/packages/flutter/lib/src/scheduler/binding.dart
@@ -209,7 +209,7 @@ mixin SchedulerBinding on BindingBase, ServicesBinding {
     if (!kReleaseMode) {
       int frameNumber = 0;
       addTimingsCallback((List<FrameTiming> timings) {
-        for (FrameTiming frameTiming in timings) {
+        for (final FrameTiming frameTiming in timings) {
           frameNumber += 1;
           _profileFramePostEvent(frameNumber, frameTiming);
         }
@@ -249,7 +249,7 @@ mixin SchedulerBinding on BindingBase, ServicesBinding {
   void _executeTimingsCallbacks(List<FrameTiming> timings) {
     final List<TimingsCallback> clonedCallbacks =
         List<TimingsCallback>.from(_timingsCallbacks);
-    for (TimingsCallback callback in clonedCallbacks) {
+    for (final TimingsCallback callback in clonedCallbacks) {
       try {
         if (_timingsCallbacks.contains(callback)) {
           callback(timings);
@@ -582,7 +582,7 @@ mixin SchedulerBinding on BindingBase, ServicesBinding {
                 'The stack traces for when they were registered are as follows:'
               );
             }
-            for (int id in callbacks.keys) {
+            for (final int id in callbacks.keys) {
               final _FrameCallbackEntry entry = callbacks[id];
               yield DiagnosticsStackTrace('── callback $id ──', entry.debugStack, showSeparator: false);
             }
@@ -1043,7 +1043,7 @@ mixin SchedulerBinding on BindingBase, ServicesBinding {
     try {
       // PERSISTENT FRAME CALLBACKS
       _schedulerPhase = SchedulerPhase.persistentCallbacks;
-      for (FrameCallback callback in _persistentCallbacks)
+      for (final FrameCallback callback in _persistentCallbacks)
         _invokeFrameCallback(callback, _currentFrameTimeStamp);
 
       // POST-FRAME CALLBACKS
@@ -1051,7 +1051,7 @@ mixin SchedulerBinding on BindingBase, ServicesBinding {
       final List<FrameCallback> localPostFrameCallbacks =
           List<FrameCallback>.from(_postFrameCallbacks);
       _postFrameCallbacks.clear();
-      for (FrameCallback callback in localPostFrameCallbacks)
+      for (final FrameCallback callback in localPostFrameCallbacks)
         _invokeFrameCallback(callback, _currentFrameTimeStamp);
     } finally {
       _schedulerPhase = SchedulerPhase.idle;
diff --git a/packages/flutter/lib/src/semantics/semantics.dart b/packages/flutter/lib/src/semantics/semantics.dart
index 3d17560698b..5831864fada 100644
--- a/packages/flutter/lib/src/semantics/semantics.dart
+++ b/packages/flutter/lib/src/semantics/semantics.dart
@@ -386,7 +386,7 @@ class SemanticsData extends Diagnosticable {
     properties.add(DoubleProperty('elevation', elevation, defaultValue: 0.0));
     properties.add(DoubleProperty('thickness', thickness, defaultValue: 0.0));
     final List<String> actionSummary = <String>[
-      for (SemanticsAction action in SemanticsAction.values.values)
+      for (final SemanticsAction action in SemanticsAction.values.values)
         if ((actions & action.index) != 0)
           describeEnum(action),
     ];
@@ -397,7 +397,7 @@ class SemanticsData extends Diagnosticable {
     properties.add(IterableProperty<String>('customActions', customSemanticsActionSummary, ifEmpty: null));
 
     final List<String> flagSummary = <String>[
-      for (SemanticsFlag flag in SemanticsFlag.values.values)
+      for (final SemanticsFlag flag in SemanticsFlag.values.values)
         if ((flags & flag.index) != 0)
           describeEnum(flag),
     ];
@@ -1397,25 +1397,25 @@ class SemanticsNode extends AbstractNode with DiagnosticableTreeMixin {
     }());
     assert(() {
       final Set<SemanticsNode> seenChildren = <SemanticsNode>{};
-      for (SemanticsNode child in newChildren)
+      for (final SemanticsNode child in newChildren)
         assert(seenChildren.add(child)); // check for duplicate adds
       return true;
     }());
 
     // The goal of this function is updating sawChange.
     if (_children != null) {
-      for (SemanticsNode child in _children)
+      for (final SemanticsNode child in _children)
         child._dead = true;
     }
     if (newChildren != null) {
-      for (SemanticsNode child in newChildren) {
+      for (final SemanticsNode child in newChildren) {
         assert(!child.isInvisible, 'Child $child is invisible and should not be added as a child of $this.');
         child._dead = false;
       }
     }
     bool sawChange = false;
     if (_children != null) {
-      for (SemanticsNode child in _children) {
+      for (final SemanticsNode child in _children) {
         if (child._dead) {
           if (child.parent == this) {
             // we might have already had our child stolen from us by
@@ -1427,7 +1427,7 @@ class SemanticsNode extends AbstractNode with DiagnosticableTreeMixin {
       }
     }
     if (newChildren != null) {
-      for (SemanticsNode child in newChildren) {
+      for (final SemanticsNode child in newChildren) {
         if (child.parent != this) {
           if (child.parent != null) {
             // we're rebuilding the tree from the bottom up, so it's possible
@@ -1473,7 +1473,7 @@ class SemanticsNode extends AbstractNode with DiagnosticableTreeMixin {
   /// returns false.
   void visitChildren(SemanticsNodeVisitor visitor) {
     if (_children != null) {
-      for (SemanticsNode child in _children) {
+      for (final SemanticsNode child in _children) {
         if (!visitor(child))
           return;
       }
@@ -1487,7 +1487,7 @@ class SemanticsNode extends AbstractNode with DiagnosticableTreeMixin {
   /// returned true, otherwise returns false.
   bool _visitDescendants(SemanticsNodeVisitor visitor) {
     if (_children != null) {
-      for (SemanticsNode child in _children) {
+      for (final SemanticsNode child in _children) {
         if (!visitor(child) || !child._visitDescendants(visitor))
           return false;
       }
@@ -1519,7 +1519,7 @@ class SemanticsNode extends AbstractNode with DiagnosticableTreeMixin {
       _markDirty();
     }
     if (_children != null) {
-      for (SemanticsNode child in _children)
+      for (final SemanticsNode child in _children)
         child.attach(owner);
     }
   }
@@ -1533,7 +1533,7 @@ class SemanticsNode extends AbstractNode with DiagnosticableTreeMixin {
     super.detach();
     assert(owner == null);
     if (_children != null) {
-      for (SemanticsNode child in _children) {
+      for (final SemanticsNode child in _children) {
         // The list of children may be stale and may contain nodes that have
         // been assigned to a different parent.
         if (child.parent == this)
@@ -1910,7 +1910,7 @@ class SemanticsNode extends AbstractNode with DiagnosticableTreeMixin {
     final double elevation = _elevation;
     double thickness = _thickness;
     final Set<int> customSemanticsActionIds = <int>{};
-    for (CustomSemanticsAction action in _customSemanticsActions.keys)
+    for (final CustomSemanticsAction action in _customSemanticsActions.keys)
       customSemanticsActionIds.add(CustomSemanticsAction.getIdentifier(action));
     if (hintOverrides != null) {
       if (hintOverrides.onTapHint != null) {
@@ -1955,7 +1955,7 @@ class SemanticsNode extends AbstractNode with DiagnosticableTreeMixin {
           mergedTags.addAll(node.tags);
         }
         if (node._customSemanticsActions != null) {
-          for (CustomSemanticsAction action in _customSemanticsActions.keys)
+          for (final CustomSemanticsAction action in _customSemanticsActions.keys)
             customSemanticsActionIds.add(CustomSemanticsAction.getIdentifier(action));
         }
         if (node.hintOverrides != null) {
@@ -2356,7 +2356,7 @@ class _SemanticsSortGroup extends Comparable<_SemanticsSortGroup> {
   /// then sorts them using [sortedWithinKnot].
   List<SemanticsNode> sortedWithinVerticalGroup() {
     final List<_BoxEdge> edges = <_BoxEdge>[];
-    for (SemanticsNode child in nodes) {
+    for (final SemanticsNode child in nodes) {
       // Using a small delta to shrink child rects removes overlapping cases.
       final Rect childRect = child.rect.deflate(0.1);
       edges.add(_BoxEdge(
@@ -2375,7 +2375,7 @@ class _SemanticsSortGroup extends Comparable<_SemanticsSortGroup> {
     List<_SemanticsSortGroup> horizontalGroups = <_SemanticsSortGroup>[];
     _SemanticsSortGroup group;
     int depth = 0;
-    for (_BoxEdge edge in edges) {
+    for (final _BoxEdge edge in edges) {
       if (edge.isLeadingEdge) {
         depth += 1;
         group ??= _SemanticsSortGroup(
@@ -2424,10 +2424,10 @@ class _SemanticsSortGroup extends Comparable<_SemanticsSortGroup> {
     }
     final Map<int, SemanticsNode> nodeMap = <int, SemanticsNode>{};
     final Map<int, int> edges = <int, int>{};
-    for (SemanticsNode node in nodes) {
+    for (final SemanticsNode node in nodes) {
       nodeMap[node.id] = node;
       final Offset center = _pointInParentCoordinates(node, node.rect.center);
-      for (SemanticsNode nextNode in nodes) {
+      for (final SemanticsNode nextNode in nodes) {
         if (identical(node, nextNode) || edges[nextNode.id] == node.id) {
           // Skip self or when we've already established that the next node
           // points to current node.
@@ -2499,7 +2499,7 @@ Offset _pointInParentCoordinates(SemanticsNode node, Offset point) {
 /// For an illustration of the algorithm see http://bit.ly/flutter-default-traversal.
 List<SemanticsNode> _childrenInDefaultOrder(List<SemanticsNode> children, TextDirection textDirection) {
   final List<_BoxEdge> edges = <_BoxEdge>[];
-  for (SemanticsNode child in children) {
+  for (final SemanticsNode child in children) {
     assert(child.rect.isFinite);
     // Using a small delta to shrink child rects removes overlapping cases.
     final Rect childRect = child.rect.deflate(0.1);
@@ -2519,7 +2519,7 @@ List<SemanticsNode> _childrenInDefaultOrder(List<SemanticsNode> children, TextDi
   final List<_SemanticsSortGroup> verticalGroups = <_SemanticsSortGroup>[];
   _SemanticsSortGroup group;
   int depth = 0;
-  for (_BoxEdge edge in edges) {
+  for (final _BoxEdge edge in edges) {
     if (edge.isLeadingEdge) {
       depth += 1;
       group ??= _SemanticsSortGroup(
@@ -2616,7 +2616,7 @@ class SemanticsOwner extends ChangeNotifier {
       _detachedNodes.clear();
       localDirtyNodes.sort((SemanticsNode a, SemanticsNode b) => a.depth - b.depth);
       visitedNodes.addAll(localDirtyNodes);
-      for (SemanticsNode node in localDirtyNodes) {
+      for (final SemanticsNode node in localDirtyNodes) {
         assert(node._dirty);
         assert(node.parent == null || !node.parent.isPartOfNodeMerging || node.isMergedIntoParent);
         if (node.isPartOfNodeMerging) {
@@ -2629,7 +2629,7 @@ class SemanticsOwner extends ChangeNotifier {
     }
     visitedNodes.sort((SemanticsNode a, SemanticsNode b) => a.depth - b.depth);
     final ui.SemanticsUpdateBuilder builder = ui.SemanticsUpdateBuilder();
-    for (SemanticsNode node in visitedNodes) {
+    for (final SemanticsNode node in visitedNodes) {
       assert(node.parent?._dirty != true); // could be null (no parent) or false (not dirty)
       // The _serialize() method marks the node as not dirty, and
       // recurses through the tree to do a deep serialization of all
@@ -2645,7 +2645,7 @@ class SemanticsOwner extends ChangeNotifier {
         node._addToUpdate(builder, customSemanticsActionIds);
     }
     _dirtyNodes.clear();
-    for (int actionId in customSemanticsActionIds) {
+    for (final int actionId in customSemanticsActionIds) {
       final CustomSemanticsAction action = CustomSemanticsAction.getAction(actionId);
       builder.updateCustomAction(id: actionId, label: action.label, hint: action.hint, overrideId: action.action?.index ?? -1);
     }
@@ -2710,7 +2710,7 @@ class SemanticsOwner extends ChangeNotifier {
       return result?._actions[action];
     }
     if (node.hasChildren) {
-      for (SemanticsNode child in node._children.reversed) {
+      for (final SemanticsNode child in node._children.reversed) {
         final _SemanticsActionHandler handler = _getSemanticsActionHandlerForPosition(child, position, action);
         if (handler != null)
           return handler;
diff --git a/packages/flutter/lib/src/semantics/semantics_event.dart b/packages/flutter/lib/src/semantics/semantics_event.dart
index 657c4d4183a..71b96b7d773 100644
--- a/packages/flutter/lib/src/semantics/semantics_event.dart
+++ b/packages/flutter/lib/src/semantics/semantics_event.dart
@@ -46,7 +46,7 @@ abstract class SemanticsEvent {
     final List<String> pairs = <String>[];
     final Map<String, dynamic> dataMap = getDataMap();
     final List<String> sortedKeys = dataMap.keys.toList()..sort();
-    for (String key in sortedKeys)
+    for (final String key in sortedKeys)
       pairs.add('$key: ${dataMap[key]}');
     return '$runtimeType(${pairs.join(', ')})';
   }
diff --git a/packages/flutter/lib/src/services/binding.dart b/packages/flutter/lib/src/services/binding.dart
index cd1b7e60432..88a320e0713 100644
--- a/packages/flutter/lib/src/services/binding.dart
+++ b/packages/flutter/lib/src/services/binding.dart
@@ -101,7 +101,7 @@ mixin ServicesBinding on BindingBase {
     final String _licenseSeparator = '\n' + ('-' * 80) + '\n';
     final List<LicenseEntry> result = <LicenseEntry>[];
     final List<String> licenses = rawLicenses.split(_licenseSeparator);
-    for (String license in licenses) {
+    for (final String license in licenses) {
       final int split = license.indexOf('\n\n');
       if (split >= 0) {
         result.add(LicenseEntryWithLineBreaks(
diff --git a/packages/flutter/lib/src/services/keyboard_key.dart b/packages/flutter/lib/src/services/keyboard_key.dart
index c9eb338f245..3c8e0b3897b 100644
--- a/packages/flutter/lib/src/services/keyboard_key.dart
+++ b/packages/flutter/lib/src/services/keyboard_key.dart
@@ -246,7 +246,7 @@ class LogicalKeyboardKey extends KeyboardKey {
   /// [control], so that the question "is any control key down?" can be asked.
   static Set<LogicalKeyboardKey> collapseSynonyms(Set<LogicalKeyboardKey> input) {
     final Set<LogicalKeyboardKey> result = <LogicalKeyboardKey>{};
-    for (LogicalKeyboardKey key in input) {
+    for (final LogicalKeyboardKey key in input) {
       final LogicalKeyboardKey synonym = _synonyms[key];
       result.add(synonym ?? key);
     }
diff --git a/packages/flutter/lib/src/services/platform_channel.dart b/packages/flutter/lib/src/services/platform_channel.dart
index 978e16ec951..3a32f36eec9 100644
--- a/packages/flutter/lib/src/services/platform_channel.dart
+++ b/packages/flutter/lib/src/services/platform_channel.dart
@@ -289,7 +289,7 @@ class MethodChannel {
   ///   } else if ([@"getSongs" isEqualToString:call.method]) {
   ///     NSArray* items = [BWPlayApi items];
   ///     NSMutableArray* json = [NSMutableArray arrayWithCapacity:items.count];
-  ///     for (BWPlayItem* item in items) {
+  ///     for (final BWPlayItem* item in items) {
   ///       [json addObject:@{@"id":item.itemId, @"title":item.name, @"artist":item.artist}];
   ///     }
   ///     result(json);
diff --git a/packages/flutter/lib/src/services/platform_views.dart b/packages/flutter/lib/src/services/platform_views.dart
index 70022fc750c..646d4e692bb 100644
--- a/packages/flutter/lib/src/services/platform_views.dart
+++ b/packages/flutter/lib/src/services/platform_views.dart
@@ -633,7 +633,7 @@ class AndroidViewController {
     }
     _textureId = await SystemChannels.platform_views.invokeMethod('create', args);
     _state = _AndroidViewState.created;
-    for (PlatformViewCreatedCallback callback in _platformViewCreatedCallbacks) {
+    for (final PlatformViewCreatedCallback callback in _platformViewCreatedCallbacks) {
       callback(id);
     }
   }
diff --git a/packages/flutter/lib/src/services/raw_keyboard.dart b/packages/flutter/lib/src/services/raw_keyboard.dart
index 6d3969d3c18..3a841c0712c 100644
--- a/packages/flutter/lib/src/services/raw_keyboard.dart
+++ b/packages/flutter/lib/src/services/raw_keyboard.dart
@@ -165,7 +165,7 @@ abstract class RawKeyEventData {
   /// event, and the keyboard side or sides that the key was on.
   Map<ModifierKey, KeyboardSide> get modifiersPressed {
     final Map<ModifierKey, KeyboardSide> result = <ModifierKey, KeyboardSide>{};
-    for (ModifierKey key in ModifierKey.values) {
+    for (final ModifierKey key in ModifierKey.values) {
       if (isModifierPressed(key)) {
         result[key] = getModifierSide(key);
       }
@@ -523,7 +523,7 @@ class RawKeyboard {
     if (_listeners.isEmpty) {
       return;
     }
-    for (ValueChanged<RawKeyEvent> listener in List<ValueChanged<RawKeyEvent>>.from(_listeners)) {
+    for (final ValueChanged<RawKeyEvent> listener in List<ValueChanged<RawKeyEvent>>.from(_listeners)) {
       if (_listeners.contains(listener)) {
         listener(event);
       }
@@ -575,7 +575,7 @@ class RawKeyboard {
   void _synchronizeModifiers(RawKeyEvent event) {
     final Map<ModifierKey, KeyboardSide> modifiersPressed = event.data.modifiersPressed;
     final Set<LogicalKeyboardKey> modifierKeys = <LogicalKeyboardKey>{};
-    for (ModifierKey key in modifiersPressed.keys) {
+    for (final ModifierKey key in modifiersPressed.keys) {
       final Set<LogicalKeyboardKey> mappedKeys = _modifierKeyMap[_ModifierSidePair(key, modifiersPressed[key])];
       assert(mappedKeys != null,
         'Platform key support for ${Platform.operatingSystem} is '
diff --git a/packages/flutter/lib/src/services/system_chrome.dart b/packages/flutter/lib/src/services/system_chrome.dart
index b20413acf62..ebd7bfe1599 100644
--- a/packages/flutter/lib/src/services/system_chrome.dart
+++ b/packages/flutter/lib/src/services/system_chrome.dart
@@ -207,7 +207,7 @@ class SystemUiOverlayStyle {
 }
 
 List<String> _stringify(List<dynamic> list) => <String>[
-  for (dynamic item in list) item.toString(),
+  for (final dynamic item in list) item.toString(),
 ];
 
 /// Controls specific aspects of the operating system's graphical interface and
diff --git a/packages/flutter/lib/src/widgets/animated_list.dart b/packages/flutter/lib/src/widgets/animated_list.dart
index a9477beccdd..6298411c474 100644
--- a/packages/flutter/lib/src/widgets/animated_list.dart
+++ b/packages/flutter/lib/src/widgets/animated_list.dart
@@ -828,7 +828,7 @@ class SliverAnimatedListState extends State<SliverAnimatedList> with TickerProvi
 
   @override
   void dispose() {
-    for (_ActiveItem item in _incomingItems.followedBy(_outgoingItems)) {
+    for (final _ActiveItem item in _incomingItems.followedBy(_outgoingItems)) {
       item.controller.dispose();
     }
     super.dispose();
@@ -852,7 +852,7 @@ class SliverAnimatedListState extends State<SliverAnimatedList> with TickerProvi
 
   int _indexToItemIndex(int index) {
     int itemIndex = index;
-    for (_ActiveItem item in _outgoingItems) {
+    for (final _ActiveItem item in _outgoingItems) {
       if (item.itemIndex <= itemIndex)
         itemIndex += 1;
       else
@@ -863,7 +863,7 @@ class SliverAnimatedListState extends State<SliverAnimatedList> with TickerProvi
 
   int _itemIndexToIndex(int itemIndex) {
     int index = itemIndex;
-    for (_ActiveItem item in _outgoingItems) {
+    for (final _ActiveItem item in _outgoingItems) {
       assert(item.itemIndex != itemIndex);
       if (item.itemIndex < itemIndex)
         index -= 1;
@@ -892,11 +892,11 @@ class SliverAnimatedListState extends State<SliverAnimatedList> with TickerProvi
 
     // Increment the incoming and outgoing item indices to account
     // for the insertion.
-    for (_ActiveItem item in _incomingItems) {
+    for (final _ActiveItem item in _incomingItems) {
       if (item.itemIndex >= itemIndex)
         item.itemIndex += 1;
     }
-    for (_ActiveItem item in _outgoingItems) {
+    for (final _ActiveItem item in _outgoingItems) {
       if (item.itemIndex >= itemIndex)
         item.itemIndex += 1;
     }
@@ -956,11 +956,11 @@ class SliverAnimatedListState extends State<SliverAnimatedList> with TickerProvi
 
       // Decrement the incoming and outgoing item indices to account
       // for the removal.
-      for (_ActiveItem item in _incomingItems) {
+      for (final _ActiveItem item in _incomingItems) {
         if (item.itemIndex > outgoingItem.itemIndex)
           item.itemIndex -= 1;
       }
-      for (_ActiveItem item in _outgoingItems) {
+      for (final _ActiveItem item in _outgoingItems) {
         if (item.itemIndex > outgoingItem.itemIndex)
           item.itemIndex -= 1;
       }
diff --git a/packages/flutter/lib/src/widgets/animated_switcher.dart b/packages/flutter/lib/src/widgets/animated_switcher.dart
index 4c29e4a99a1..10d1c5037c3 100644
--- a/packages/flutter/lib/src/widgets/animated_switcher.dart
+++ b/packages/flutter/lib/src/widgets/animated_switcher.dart
@@ -425,7 +425,7 @@ class _AnimatedSwitcherState extends State<AnimatedSwitcher> with TickerProvider
   void dispose() {
     if (_currentEntry != null)
       _currentEntry.controller.dispose();
-    for (_ChildEntry entry in _outgoingEntries)
+    for (final _ChildEntry entry in _outgoingEntries)
       entry.controller.dispose();
     super.dispose();
   }
diff --git a/packages/flutter/lib/src/widgets/app.dart b/packages/flutter/lib/src/widgets/app.dart
index bd3ce0f33d7..7c29768f7c4 100644
--- a/packages/flutter/lib/src/widgets/app.dart
+++ b/packages/flutter/lib/src/widgets/app.dart
@@ -1110,7 +1110,7 @@ class _WidgetsAppState extends State<WidgetsApp> with WidgetsBindingObserver {
     final Map<String, Locale> languageAndScriptLocales = HashMap<String, Locale>();
     final Map<String, Locale> languageLocales = HashMap<String, Locale>();
     final Map<String, Locale> countryLocales = HashMap<String, Locale>();
-    for (Locale locale in supportedLocales) {
+    for (final Locale locale in supportedLocales) {
       allSupportedLocales['${locale.languageCode}_${locale.scriptCode}_${locale.countryCode}'] ??= locale;
       languageAndScriptLocales['${locale.languageCode}_${locale.scriptCode}'] ??= locale;
       languageAndCountryLocales['${locale.languageCode}_${locale.countryCode}'] ??= locale;
@@ -1209,7 +1209,7 @@ class _WidgetsAppState extends State<WidgetsApp> with WidgetsBindingObserver {
     assert(() {
       final Set<Type> unsupportedTypes =
         _localizationsDelegates.map<Type>((LocalizationsDelegate<dynamic> delegate) => delegate.type).toSet();
-      for (LocalizationsDelegate<dynamic> delegate in _localizationsDelegates) {
+      for (final LocalizationsDelegate<dynamic> delegate in _localizationsDelegates) {
         if (!unsupportedTypes.contains(delegate.type))
           continue;
         if (delegate.isSupported(appLocale))
@@ -1230,7 +1230,7 @@ class _WidgetsAppState extends State<WidgetsApp> with WidgetsBindingObserver {
         'Warning: This application\'s locale, $appLocale, is not supported by all of its\n'
         'localization delegates.'
       );
-      for (Type unsupportedType in unsupportedTypes) {
+      for (final Type unsupportedType in unsupportedTypes) {
         // Currently the Cupertino library only provides english localizations.
         // Remove this when https://github.com/flutter/flutter/issues/23847
         // is fixed.
diff --git a/packages/flutter/lib/src/widgets/automatic_keep_alive.dart b/packages/flutter/lib/src/widgets/automatic_keep_alive.dart
index aafc4417d08..5d61d0b0e66 100644
--- a/packages/flutter/lib/src/widgets/automatic_keep_alive.dart
+++ b/packages/flutter/lib/src/widgets/automatic_keep_alive.dart
@@ -66,7 +66,7 @@ class _AutomaticKeepAliveState extends State<AutomaticKeepAlive> {
   @override
   void dispose() {
     if (_handles != null) {
-      for (Listenable handle in _handles.keys)
+      for (final Listenable handle in _handles.keys)
         handle.removeListener(_handles[handle]);
     }
     super.dispose();
diff --git a/packages/flutter/lib/src/widgets/basic.dart b/packages/flutter/lib/src/widgets/basic.dart
index a1143b93070..eb236eb0ca0 100644
--- a/packages/flutter/lib/src/widgets/basic.dart
+++ b/packages/flutter/lib/src/widgets/basic.dart
@@ -6784,7 +6784,7 @@ class KeyedSubtree extends StatelessWidget {
 
     final List<Widget> itemsWithUniqueKeys = <Widget>[];
     int itemIndex = baseIndex;
-    for (Widget item in items) {
+    for (final Widget item in items) {
       itemsWithUniqueKeys.add(KeyedSubtree.wrap(item, itemIndex));
       itemIndex += 1;
     }
diff --git a/packages/flutter/lib/src/widgets/binding.dart b/packages/flutter/lib/src/widgets/binding.dart
index 1fba2f54799..995cb3ea891 100644
--- a/packages/flutter/lib/src/widgets/binding.dart
+++ b/packages/flutter/lib/src/widgets/binding.dart
@@ -447,28 +447,28 @@ mixin WidgetsBinding on BindingBase, ServicesBinding, SchedulerBinding, GestureB
   @override
   void handleMetricsChanged() {
     super.handleMetricsChanged();
-    for (WidgetsBindingObserver observer in _observers)
+    for (final WidgetsBindingObserver observer in _observers)
       observer.didChangeMetrics();
   }
 
   @override
   void handleTextScaleFactorChanged() {
     super.handleTextScaleFactorChanged();
-    for (WidgetsBindingObserver observer in _observers)
+    for (final WidgetsBindingObserver observer in _observers)
       observer.didChangeTextScaleFactor();
   }
 
   @override
   void handlePlatformBrightnessChanged() {
     super.handlePlatformBrightnessChanged();
-    for (WidgetsBindingObserver observer in _observers)
+    for (final WidgetsBindingObserver observer in _observers)
       observer.didChangePlatformBrightness();
   }
 
   @override
   void handleAccessibilityFeaturesChanged() {
     super.handleAccessibilityFeaturesChanged();
-    for (WidgetsBindingObserver observer in _observers)
+    for (final WidgetsBindingObserver observer in _observers)
       observer.didChangeAccessibilityFeatures();
   }
 
@@ -492,7 +492,7 @@ mixin WidgetsBinding on BindingBase, ServicesBinding, SchedulerBinding, GestureB
   @protected
   @mustCallSuper
   void dispatchLocalesChanged(List<Locale> locales) {
-    for (WidgetsBindingObserver observer in _observers)
+    for (final WidgetsBindingObserver observer in _observers)
       observer.didChangeLocales(locales);
   }
 
@@ -505,7 +505,7 @@ mixin WidgetsBinding on BindingBase, ServicesBinding, SchedulerBinding, GestureB
   @protected
   @mustCallSuper
   void dispatchAccessibilityFeaturesChanged() {
-    for (WidgetsBindingObserver observer in _observers)
+    for (final WidgetsBindingObserver observer in _observers)
       observer.didChangeAccessibilityFeatures();
   }
 
@@ -525,7 +525,7 @@ mixin WidgetsBinding on BindingBase, ServicesBinding, SchedulerBinding, GestureB
   /// [SystemChannels.navigation].
   @protected
   Future<void> handlePopRoute() async {
-    for (WidgetsBindingObserver observer in List<WidgetsBindingObserver>.from(_observers)) {
+    for (final WidgetsBindingObserver observer in List<WidgetsBindingObserver>.from(_observers)) {
       if (await observer.didPopRoute())
         return;
     }
@@ -545,7 +545,7 @@ mixin WidgetsBinding on BindingBase, ServicesBinding, SchedulerBinding, GestureB
   @protected
   @mustCallSuper
   Future<void> handlePushRoute(String route) async {
-    for (WidgetsBindingObserver observer in List<WidgetsBindingObserver>.from(_observers)) {
+    for (final WidgetsBindingObserver observer in List<WidgetsBindingObserver>.from(_observers)) {
       if (await observer.didPushRoute(route))
         return;
     }
@@ -564,7 +564,7 @@ mixin WidgetsBinding on BindingBase, ServicesBinding, SchedulerBinding, GestureB
   @override
   void handleAppLifecycleStateChanged(AppLifecycleState state) {
     super.handleAppLifecycleStateChanged(state);
-    for (WidgetsBindingObserver observer in _observers)
+    for (final WidgetsBindingObserver observer in _observers)
       observer.didChangeAppLifecycleState(state);
   }
 
@@ -577,7 +577,7 @@ mixin WidgetsBinding on BindingBase, ServicesBinding, SchedulerBinding, GestureB
   /// This method exposes the `memoryPressure` notification from
   /// [SystemChannels.system].
   void handleMemoryPressure() {
-    for (WidgetsBindingObserver observer in _observers)
+    for (final WidgetsBindingObserver observer in _observers)
       observer.didHaveMemoryPressure();
   }
 
diff --git a/packages/flutter/lib/src/widgets/debug.dart b/packages/flutter/lib/src/widgets/debug.dart
index 2c334c00b50..79a8746fe96 100644
--- a/packages/flutter/lib/src/widgets/debug.dart
+++ b/packages/flutter/lib/src/widgets/debug.dart
@@ -108,7 +108,7 @@ bool debugHighlightDeprecatedWidgets = false;
 
 Key _firstNonUniqueKey(Iterable<Widget> widgets) {
   final Set<Key> keySet = HashSet<Key>();
-  for (Widget widget in widgets) {
+  for (final Widget widget in widgets) {
     assert(widget != null);
     if (widget.key == null)
       continue;
diff --git a/packages/flutter/lib/src/widgets/drag_target.dart b/packages/flutter/lib/src/widgets/drag_target.dart
index 1365be2e646..78d1261aaef 100644
--- a/packages/flutter/lib/src/widgets/drag_target.dart
+++ b/packages/flutter/lib/src/widgets/drag_target.dart
@@ -669,7 +669,7 @@ class _DragAvatar<T> extends Drag {
   Iterable<_DragTargetState<T>> _getDragTargets(Iterable<HitTestEntry> path) sync* {
     // Look for the RenderBoxes that corresponds to the hit target (the hit target
     // widgets build RenderMetaData boxes for us for this purpose).
-    for (HitTestEntry entry in path) {
+    for (final HitTestEntry entry in path) {
       final HitTestTarget target = entry.target;
       if (target is RenderMetaData) {
         final dynamic metaData = target.metaData;
diff --git a/packages/flutter/lib/src/widgets/editable_text.dart b/packages/flutter/lib/src/widgets/editable_text.dart
index 54e2f14fccb..8188fb62930 100644
--- a/packages/flutter/lib/src/widgets/editable_text.dart
+++ b/packages/flutter/lib/src/widgets/editable_text.dart
@@ -1618,7 +1618,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
   void _formatAndSetValue(TextEditingValue value) {
     final bool textChanged = _value?.text != value?.text;
     if (textChanged && widget.inputFormatters != null && widget.inputFormatters.isNotEmpty) {
-      for (TextInputFormatter formatter in widget.inputFormatters)
+      for (final TextInputFormatter formatter in widget.inputFormatters)
         value = formatter.formatEditUpdate(_value, value);
       _value = value;
       _updateRemoteEditingValueIfNeeded();
diff --git a/packages/flutter/lib/src/widgets/focus_manager.dart b/packages/flutter/lib/src/widgets/focus_manager.dart
index e5d9a000847..2942c7c4fd9 100644
--- a/packages/flutter/lib/src/widgets/focus_manager.dart
+++ b/packages/flutter/lib/src/widgets/focus_manager.dart
@@ -24,7 +24,7 @@ bool _focusDebug(String message, [Iterable<String> details]) {
   if (_kDebugFocus) {
     debugPrint('FOCUS: $message');
     if (details != null && details.isNotEmpty) {
-      for (String detail in details) {
+      for (final String detail in details) {
         debugPrint('    $detail');
       }
     }
@@ -507,7 +507,7 @@ class FocusNode with DiagnosticableTreeMixin, ChangeNotifier {
   Iterable<FocusNode> get descendants {
     if (_descendants == null) {
       final List<FocusNode> result = <FocusNode>[];
-      for (FocusNode child in _children) {
+      for (final FocusNode child in _children) {
         result.addAll(child.descendants);
         result.add(child);
       }
@@ -732,7 +732,7 @@ class FocusNode with DiagnosticableTreeMixin, ChangeNotifier {
 
     node._parent = null;
     _children.remove(node);
-    for (FocusNode ancestor in ancestors) {
+    for (final FocusNode ancestor in ancestors) {
       ancestor._descendants = null;
     }
     _descendants = null;
@@ -741,7 +741,7 @@ class FocusNode with DiagnosticableTreeMixin, ChangeNotifier {
 
   void _updateManager(FocusManager manager) {
     _manager = manager;
-    for (FocusNode descendant in descendants) {
+    for (final FocusNode descendant in descendants) {
       descendant._manager = manager;
       descendant._ancestors = null;
     }
@@ -766,7 +766,7 @@ class FocusNode with DiagnosticableTreeMixin, ChangeNotifier {
     child._parent = this;
     child._ancestors = null;
     child._updateManager(_manager);
-    for (FocusNode ancestor in child.ancestors) {
+    for (final FocusNode ancestor in child.ancestors) {
       ancestor._descendants = null;
     }
     if (hadFocus) {
@@ -869,7 +869,7 @@ class FocusNode with DiagnosticableTreeMixin, ChangeNotifier {
   /// child in that scope is removed, the previous focus returns.
   void _setAsFocusedChild() {
     FocusNode scopeFocus = this;
-    for (FocusScopeNode ancestor in ancestors.whereType<FocusScopeNode>()) {
+    for (final FocusScopeNode ancestor in ancestors.whereType<FocusScopeNode>()) {
       assert(scopeFocus != ancestor, 'Somehow made a loop by setting focusedChild to its scope.');
       assert(_focusDebug('Setting $scopeFocus as focused child for scope:', <String>[ancestor.toString()]));
       // Remove it anywhere in the focused child history.
@@ -1258,7 +1258,7 @@ class FocusManager with DiagnosticableTreeMixin {
       return;
     }
     final List<ValueChanged<FocusHighlightMode>> localListeners = List<ValueChanged<FocusHighlightMode>>.from(_listeners);
-    for (ValueChanged<FocusHighlightMode> listener in localListeners) {
+    for (final ValueChanged<FocusHighlightMode> listener in localListeners) {
       try {
         if (_listeners.contains(listener)) {
           listener(_highlightMode);
@@ -1322,7 +1322,7 @@ class FocusManager with DiagnosticableTreeMixin {
       return;
     }
     bool handled = false;
-    for (FocusNode node in <FocusNode>[_primaryFocus, ..._primaryFocus.ancestors]) {
+    for (final FocusNode node in <FocusNode>[_primaryFocus, ..._primaryFocus.ancestors]) {
       if (node.onKey != null && node.onKey(node, event)) {
         assert(_focusDebug('Node $node handled key event $event.'));
         handled = true;
@@ -1409,7 +1409,7 @@ class FocusManager with DiagnosticableTreeMixin {
       }
     }
     assert(_focusDebug('Notifying ${_dirtyNodes.length} dirty nodes:', _dirtyNodes.toList().map<String>((FocusNode node) => node.toString())));
-    for (FocusNode node in _dirtyNodes) {
+    for (final FocusNode node in _dirtyNodes) {
       node._notify();
     }
     _dirtyNodes.clear();
diff --git a/packages/flutter/lib/src/widgets/focus_traversal.dart b/packages/flutter/lib/src/widgets/focus_traversal.dart
index 09be0f533e8..c88ed395531 100644
--- a/packages/flutter/lib/src/widgets/focus_traversal.dart
+++ b/packages/flutter/lib/src/widgets/focus_traversal.dart
@@ -618,7 +618,7 @@ class WidgetOrderFocusTraversalPolicy extends FocusTraversalPolicy with Directio
     FocusNode firstNode;
     FocusNode lastNode;
     bool visit(FocusNode node) {
-      for (FocusNode visited in node.traversalChildren) {
+      for (final FocusNode visited in node.traversalChildren) {
         firstNode ??= visited;
         if (!visit(visited)) {
           return false;
@@ -750,7 +750,7 @@ class ReadingOrderTraversalPolicy extends FocusTraversalPolicy with DirectionalF
     }
 
     final List<_SortData> data = <_SortData>[
-      for (FocusNode node in nodes) _SortData(node),
+      for (final FocusNode node in nodes) _SortData(node),
     ];
 
     // Pick the initial widget as the one that is leftmost in the band of the
@@ -800,7 +800,7 @@ class ReadingOrderTraversalPolicy extends FocusTraversalPolicy with DirectionalF
 
     final Iterable<FocusNode> maybeFlipped = forward ? sortedNodes : sortedNodes.reversed;
     FocusNode previousNode;
-    for (FocusNode node in maybeFlipped) {
+    for (final FocusNode node in maybeFlipped) {
       if (previousNode == focusedChild) {
         _focusAndEnsureVisible(
           node,
diff --git a/packages/flutter/lib/src/widgets/form.dart b/packages/flutter/lib/src/widgets/form.dart
index 1d8d94ca8dd..9b71f4b99a3 100644
--- a/packages/flutter/lib/src/widgets/form.dart
+++ b/packages/flutter/lib/src/widgets/form.dart
@@ -177,7 +177,7 @@ class FormState extends State<Form> {
 
   /// Saves every [FormField] that is a descendant of this [Form].
   void save() {
-    for (FormFieldState<dynamic> field in _fields)
+    for (final FormFieldState<dynamic> field in _fields)
       field.save();
   }
 
@@ -189,7 +189,7 @@ class FormState extends State<Form> {
   /// If the form's [Form.autovalidate] property is true, the fields will all be
   /// revalidated after being reset.
   void reset() {
-    for (FormFieldState<dynamic> field in _fields)
+    for (final FormFieldState<dynamic> field in _fields)
       field.reset();
     _fieldDidChange();
   }
@@ -205,7 +205,7 @@ class FormState extends State<Form> {
 
   bool _validate() {
     bool hasError = false;
-    for (FormFieldState<dynamic> field in _fields)
+    for (final FormFieldState<dynamic> field in _fields)
       hasError = !field.validate() || hasError;
     return !hasError;
   }
diff --git a/packages/flutter/lib/src/widgets/framework.dart b/packages/flutter/lib/src/widgets/framework.dart
index 47f3d56d154..000a1ce1da5 100644
--- a/packages/flutter/lib/src/widgets/framework.dart
+++ b/packages/flutter/lib/src/widgets/framework.dart
@@ -206,7 +206,7 @@ abstract class GlobalKey<T extends State<StatefulWidget>> extends Key {
   static void _debugVerifyIllFatedPopulation() {
     assert(() {
       Map<GlobalKey, Set<Element>> duplicates;
-      for (Element element in _debugIllFatedElements) {
+      for (final Element element in _debugIllFatedElements) {
         if (element._debugLifecycleState != _ElementLifecycle.defunct) {
           assert(element != null);
           assert(element.widget != null);
@@ -224,7 +224,7 @@ abstract class GlobalKey<T extends State<StatefulWidget>> extends Key {
       if (duplicates != null) {
         final List<DiagnosticsNode> information = <DiagnosticsNode>[];
         information.add(ErrorSummary('Multiple widgets used the same GlobalKey.'));
-        for (GlobalKey key in duplicates.keys) {
+        for (final GlobalKey key in duplicates.keys) {
           final Set<Element> elements = duplicates[key];
           // TODO(jacobr): this will omit the '- ' before each widget name and
           // use the more standard whitespace style instead. Please let me know
@@ -1501,7 +1501,7 @@ abstract class ParentDataWidget<T extends RenderObjectWidget> extends ProxyWidge
         '$runtimeType widgets must be placed directly inside $T widgets.\n'
         '$description has a $T ancestor, but there are other widgets between them:'
       );
-      for (Widget ancestor in badAncestors) {
+      for (final Widget ancestor in badAncestors) {
         if (ancestor.runtimeType == runtimeType) {
           yield ErrorDescription('- $ancestor (this is a different $runtimeType than the one with the problem)');
         } else {
@@ -2551,7 +2551,7 @@ class BuildOwner {
         return true;
       }());
     } finally {
-      for (Element element in _dirtyElements) {
+      for (final Element element in _dirtyElements) {
         assert(element._inDirtyList);
         element._inDirtyList = false;
       }
@@ -2606,13 +2606,13 @@ class BuildOwner {
           if (_debugElementsThatWillNeedToBeRebuiltDueToGlobalKeyShenanigans != null &&
               _debugElementsThatWillNeedToBeRebuiltDueToGlobalKeyShenanigans.isNotEmpty) {
             final Set<GlobalKey> keys = HashSet<GlobalKey>();
-            for (Element element in _debugElementsThatWillNeedToBeRebuiltDueToGlobalKeyShenanigans.keys) {
+            for (final Element element in _debugElementsThatWillNeedToBeRebuiltDueToGlobalKeyShenanigans.keys) {
               if (element._debugLifecycleState != _ElementLifecycle.defunct)
                 keys.addAll(_debugElementsThatWillNeedToBeRebuiltDueToGlobalKeyShenanigans[element]);
             }
             if (keys.isNotEmpty) {
               final Map<String, int> keyStringCount = HashMap<String, int>();
-              for (String key in keys.map<String>((GlobalKey key) => key.toString())) {
+              for (final String key in keys.map<String>((GlobalKey key) => key.toString())) {
                 if (keyStringCount.containsKey(key)) {
                   keyStringCount[key] += 1;
                 } else {
@@ -2629,7 +2629,7 @@ class BuildOwner {
               });
               final Iterable<Element> elements = _debugElementsThatWillNeedToBeRebuiltDueToGlobalKeyShenanigans.keys;
               final Map<String, int> elementStringCount = HashMap<String, int>();
-              for (String element in elements.map<String>((Element element) => element.toString())) {
+              for (final String element in elements.map<String>((Element element) => element.toString())) {
                 if (elementStringCount.containsKey(element)) {
                   elementStringCount[element] += 1;
                 } else {
@@ -3402,7 +3402,7 @@ abstract class Element extends DiagnosticableTree implements BuildContext {
     assert(depth != null);
     assert(_active);
     if (_dependencies != null && _dependencies.isNotEmpty) {
-      for (InheritedElement dependency in _dependencies)
+      for (final InheritedElement dependency in _dependencies)
         dependency._dependents.remove(this);
       // For expediency, we don't actually clear the list here, even though it's
       // no longer representative of what we are registered with. If we never
@@ -4914,7 +4914,7 @@ class InheritedElement extends ProxyElement {
   @override
   void notifyClients(InheritedWidget oldWidget) {
     assert(_debugCheckOwnerBuildTargetExists('notifyClients'));
-    for (Element dependent in _dependents.keys) {
+    for (final Element dependent in _dependents.keys) {
       assert(() {
         // check that it really is our descendant
         Element ancestor = dependent._parent;
@@ -5329,7 +5329,7 @@ abstract class RenderObjectElement extends Element {
 
     // Clean up any of the remaining middle nodes from the old list.
     if (haveOldChildren && oldKeyedChildren.isNotEmpty) {
-      for (Element oldChild in oldKeyedChildren.values) {
+      for (final Element oldChild in oldKeyedChildren.values) {
         if (forgottenChildren == null || !forgottenChildren.contains(oldChild))
           deactivateChild(oldChild);
       }
@@ -5612,7 +5612,7 @@ class MultiChildRenderObjectElement extends RenderObjectElement {
 
   @override
   void visitChildren(ElementVisitor visitor) {
-    for (Element child in _children) {
+    for (final Element child in _children) {
       if (!_forgottenChildren.contains(child))
         visitor(child);
     }
diff --git a/packages/flutter/lib/src/widgets/gesture_detector.dart b/packages/flutter/lib/src/widgets/gesture_detector.dart
index c8e04ea1e32..9febee15d26 100644
--- a/packages/flutter/lib/src/widgets/gesture_detector.dart
+++ b/packages/flutter/lib/src/widgets/gesture_detector.dart
@@ -990,7 +990,7 @@ class RawGestureDetectorState extends State<RawGestureDetector> {
 
   @override
   void dispose() {
-    for (GestureRecognizer recognizer in _recognizers.values)
+    for (final GestureRecognizer recognizer in _recognizers.values)
       recognizer.dispose();
     _recognizers = null;
     super.dispose();
@@ -1000,7 +1000,7 @@ class RawGestureDetectorState extends State<RawGestureDetector> {
     assert(_recognizers != null);
     final Map<Type, GestureRecognizer> oldRecognizers = _recognizers;
     _recognizers = <Type, GestureRecognizer>{};
-    for (Type type in gestures.keys) {
+    for (final Type type in gestures.keys) {
       assert(gestures[type] != null);
       assert(gestures[type]._debugAssertTypeMatches(type));
       assert(!_recognizers.containsKey(type));
@@ -1008,7 +1008,7 @@ class RawGestureDetectorState extends State<RawGestureDetector> {
       assert(_recognizers[type].runtimeType == type, 'GestureRecognizerFactory of type $type created a GestureRecognizer of type ${_recognizers[type].runtimeType}. The GestureRecognizerFactory must be specialized with the type of the class that it returns from its constructor method.');
       gestures[type].initializer(_recognizers[type]);
     }
-    for (Type type in oldRecognizers.keys) {
+    for (final Type type in oldRecognizers.keys) {
       if (!_recognizers.containsKey(type))
         oldRecognizers[type].dispose();
     }
@@ -1016,7 +1016,7 @@ class RawGestureDetectorState extends State<RawGestureDetector> {
 
   void _handlePointerDown(PointerDownEvent event) {
     assert(_recognizers != null);
-    for (GestureRecognizer recognizer in _recognizers.values)
+    for (final GestureRecognizer recognizer in _recognizers.values)
       recognizer.addPointer(event);
   }
 
diff --git a/packages/flutter/lib/src/widgets/heroes.dart b/packages/flutter/lib/src/widgets/heroes.dart
index 2629cd5dc30..7253e7bbf99 100644
--- a/packages/flutter/lib/src/widgets/heroes.dart
+++ b/packages/flutter/lib/src/widgets/heroes.dart
@@ -755,7 +755,7 @@ class HeroController extends NavigatorObserver {
 
     // Treat these invalidated flights as dismissed. Calling _handleAnimationUpdate
     // will also remove the flight from _flights.
-    for (_HeroFlight flight in invalidFlights) {
+    for (final _HeroFlight flight in invalidFlights) {
       flight._handleAnimationUpdate(AnimationStatus.dismissed);
     }
   }
@@ -834,7 +834,7 @@ class HeroController extends NavigatorObserver {
     // animation value back to what it was before it was "moved" offstage.
     to.offstage = false;
 
-    for (Object tag in fromHeroes.keys) {
+    for (final Object tag in fromHeroes.keys) {
       if (toHeroes[tag] != null) {
         final HeroFlightShuttleBuilder fromShuttleBuilder = fromHeroes[tag].widget.flightShuttleBuilder;
         final HeroFlightShuttleBuilder toShuttleBuilder = toHeroes[tag].widget.flightShuttleBuilder;
@@ -866,7 +866,7 @@ class HeroController extends NavigatorObserver {
 
     // If the from hero is gone, the flight won't start and the to hero needs to
     // be put on stage again.
-    for (Object tag in toHeroes.keys) {
+    for (final Object tag in toHeroes.keys) {
       if (fromHeroes[tag] == null)
         toHeroes[tag].ensurePlaceholderIsHidden();
     }
diff --git a/packages/flutter/lib/src/widgets/inherited_model.dart b/packages/flutter/lib/src/widgets/inherited_model.dart
index a04b8700115..e4c7efe3cb7 100644
--- a/packages/flutter/lib/src/widgets/inherited_model.dart
+++ b/packages/flutter/lib/src/widgets/inherited_model.dart
@@ -170,7 +170,7 @@ abstract class InheritedModel<T> extends InheritedWidget {
     }
 
     final InheritedElement lastModel = models.last;
-    for (InheritedElement model in models) {
+    for (final InheritedElement model in models) {
       final T value = context.dependOnInheritedElement(model, aspect: aspect) as T;
       if (model == lastModel)
         return value;
diff --git a/packages/flutter/lib/src/widgets/inherited_theme.dart b/packages/flutter/lib/src/widgets/inherited_theme.dart
index ecae20ab22b..dd2a29c4d21 100644
--- a/packages/flutter/lib/src/widgets/inherited_theme.dart
+++ b/packages/flutter/lib/src/widgets/inherited_theme.dart
@@ -147,7 +147,7 @@ class _CaptureAll extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     Widget wrappedChild = child;
-    for (InheritedTheme theme in themes)
+    for (final InheritedTheme theme in themes)
       wrappedChild = theme.wrap(context, wrappedChild);
     return wrappedChild;
   }
diff --git a/packages/flutter/lib/src/widgets/list_wheel_scroll_view.dart b/packages/flutter/lib/src/widgets/list_wheel_scroll_view.dart
index b88d1962a27..bced3d08ace 100644
--- a/packages/flutter/lib/src/widgets/list_wheel_scroll_view.dart
+++ b/packages/flutter/lib/src/widgets/list_wheel_scroll_view.dart
@@ -265,7 +265,7 @@ class FixedExtentScrollController extends ScrollController {
     }
 
     await Future.wait<void>(<Future<void>>[
-      for (_FixedExtentScrollPosition position in positions.cast<_FixedExtentScrollPosition>())
+      for (final _FixedExtentScrollPosition position in positions.cast<_FixedExtentScrollPosition>())
         position.animateTo(
           itemIndex * position.itemExtent,
           duration: duration,
@@ -279,7 +279,7 @@ class FixedExtentScrollController extends ScrollController {
   /// Jumps the item index position from its current value to the given value,
   /// without animation, and without checking if the new value is in range.
   void jumpToItem(int itemIndex) {
-    for (_FixedExtentScrollPosition position in positions.cast<_FixedExtentScrollPosition>()) {
+    for (final _FixedExtentScrollPosition position in positions.cast<_FixedExtentScrollPosition>()) {
       position.jumpTo(itemIndex * position.itemExtent);
     }
   }
diff --git a/packages/flutter/lib/src/widgets/localizations.dart b/packages/flutter/lib/src/widgets/localizations.dart
index 5ae0b6e7ebd..8dae00dd5f7 100644
--- a/packages/flutter/lib/src/widgets/localizations.dart
+++ b/packages/flutter/lib/src/widgets/localizations.dart
@@ -47,14 +47,14 @@ Future<Map<Type, dynamic>> _loadAll(Locale locale, Iterable<LocalizationsDelegat
   // locale.languageCode.
   final Set<Type> types = <Type>{};
   final List<LocalizationsDelegate<dynamic>> delegates = <LocalizationsDelegate<dynamic>>[];
-  for (LocalizationsDelegate<dynamic> delegate in allDelegates) {
+  for (final LocalizationsDelegate<dynamic> delegate in allDelegates) {
     if (!types.contains(delegate.type) && delegate.isSupported(locale)) {
       types.add(delegate.type);
       delegates.add(delegate);
     }
   }
 
-  for (LocalizationsDelegate<dynamic> delegate in delegates) {
+  for (final LocalizationsDelegate<dynamic> delegate in delegates) {
     final Future<dynamic> inputValue = delegate.load(locale);
     dynamic completedValue;
     final Future<dynamic> futureValue = inputValue.then<dynamic>((dynamic value) {
diff --git a/packages/flutter/lib/src/widgets/navigator.dart b/packages/flutter/lib/src/widgets/navigator.dart
index 344249fec6f..39484aaba85 100644
--- a/packages/flutter/lib/src/widgets/navigator.dart
+++ b/packages/flutter/lib/src/widgets/navigator.dart
@@ -1521,7 +1521,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
   @override
   void initState() {
     super.initState();
-    for (NavigatorObserver observer in widget.observers) {
+    for (final NavigatorObserver observer in widget.observers) {
       assert(observer.navigator == null);
       observer._navigator = this;
     }
@@ -1535,7 +1535,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
       final List<String> routeParts = initialRouteName.split('/');
       if (initialRouteName.isNotEmpty) {
         String routeName = '';
-        for (String part in routeParts) {
+        for (final String part in routeParts) {
           routeName += '/$part';
           plannedInitialRoutes.add(_routeNamed<dynamic>(routeName, allowNull: true, arguments: null));
         }
@@ -1564,7 +1564,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
       route ??= _routeNamed<Object>(Navigator.defaultRouteName, arguments: null);
       push(route);
     }
-    for (Route<dynamic> route in _history)
+    for (final Route<dynamic> route in _history)
       _initialOverlayEntries.addAll(route.overlayEntries);
   }
 
@@ -1572,14 +1572,14 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
   void didUpdateWidget(Navigator oldWidget) {
     super.didUpdateWidget(oldWidget);
     if (oldWidget.observers != widget.observers) {
-      for (NavigatorObserver observer in oldWidget.observers)
+      for (final NavigatorObserver observer in oldWidget.observers)
         observer._navigator = null;
-      for (NavigatorObserver observer in widget.observers) {
+      for (final NavigatorObserver observer in widget.observers) {
         assert(observer.navigator == null);
         observer._navigator = this;
       }
     }
-    for (Route<dynamic> route in _history)
+    for (final Route<dynamic> route in _history)
       route.changedExternalState();
   }
 
@@ -1590,10 +1590,10 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
       _debugLocked = true;
       return true;
     }());
-    for (NavigatorObserver observer in widget.observers)
+    for (final NavigatorObserver observer in widget.observers)
       observer._navigator = null;
     final List<Route<dynamic>> doomed = _poppedRoutes.toList()..addAll(_history);
-    for (Route<dynamic> route in doomed)
+    for (final Route<dynamic> route in doomed)
       route.dispose();
     _poppedRoutes.clear();
     _history.clear();
@@ -1609,7 +1609,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
   OverlayState get overlay => _overlayKey.currentState;
 
   OverlayEntry get _currentOverlayEntry {
-    for (Route<dynamic> route in _history.reversed) {
+    for (final Route<dynamic> route in _history.reversed) {
       if (route.overlayEntries.isNotEmpty)
         return route.overlayEntries.last;
     }
@@ -1796,7 +1796,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
       oldRoute.didChangeNext(route);
       route.didChangePrevious(oldRoute);
     }
-    for (NavigatorObserver observer in widget.observers)
+    for (final NavigatorObserver observer in widget.observers)
       observer.didPush(route, oldRoute);
     RouteNotificationMessages.maybeNotifyRouteChange(_routePushedMethod, route, oldRoute);
     assert(() {
@@ -1896,7 +1896,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
       _history[index - 1].didChangeNext(newRoute);
       newRoute.didChangePrevious(_history[index - 1]);
     }
-    for (NavigatorObserver observer in widget.observers)
+    for (final NavigatorObserver observer in widget.observers)
       observer.didReplace(newRoute: newRoute, oldRoute: oldRoute);
     RouteNotificationMessages.maybeNotifyRouteChange(_routeReplacedMethod, newRoute, oldRoute);
     assert(() {
@@ -1956,8 +1956,8 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
 
     newRoute.didPush().whenCompleteOrCancel(() {
       if (mounted) {
-        for (Route<dynamic> removedRoute in removedRoutes) {
-          for (NavigatorObserver observer in widget.observers)
+        for (final Route<dynamic> removedRoute in removedRoutes) {
+          for (final NavigatorObserver observer in widget.observers)
             observer.didRemove(removedRoute, newPrecedingRoute);
           removedRoute.dispose();
         }
@@ -1969,7 +1969,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
 
     // Notify for newRoute
     newRoute.didChangeNext(null);
-    for (NavigatorObserver observer in widget.observers)
+    for (final NavigatorObserver observer in widget.observers)
       observer.didPush(newRoute, precedingRoute);
 
     assert(() {
@@ -2020,7 +2020,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
       _history[index - 1].didChangeNext(newRoute);
       newRoute.didChangePrevious(_history[index - 1]);
     }
-    for (NavigatorObserver observer in widget.observers)
+    for (final NavigatorObserver observer in widget.observers)
       observer.didReplace(newRoute: newRoute, oldRoute: oldRoute);
     RouteNotificationMessages.maybeNotifyRouteChange(_routeReplacedMethod, newRoute, oldRoute);
     oldRoute.dispose();
@@ -2132,7 +2132,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
         if (route._navigator != null)
           _poppedRoutes.add(route);
         _history.last.didPopNext(route);
-        for (NavigatorObserver observer in widget.observers)
+        for (final NavigatorObserver observer in widget.observers)
           observer.didPop(route, _history.last);
         RouteNotificationMessages.maybeNotifyRouteChange(_routePoppedMethod, route, _history.last);
       } else {
@@ -2190,7 +2190,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
     _history.removeAt(index);
     previousRoute?.didChangeNext(nextRoute);
     nextRoute?.didChangePrevious(previousRoute);
-    for (NavigatorObserver observer in widget.observers)
+    for (final NavigatorObserver observer in widget.observers)
       observer.didRemove(route, previousRoute);
     route.dispose();
     assert(() {
@@ -2281,7 +2281,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
       // Don't operate the _history list since the gesture may be canceled.
       // In case of a back swipe, the gesture controller will call .pop() itself.
 
-      for (NavigatorObserver observer in widget.observers)
+      for (final NavigatorObserver observer in widget.observers)
         observer.didStartUserGesture(route, previousRoute);
     }
   }
@@ -2294,7 +2294,7 @@ class NavigatorState extends State<Navigator> with TickerProviderStateMixin {
     assert(_userGesturesInProgress > 0);
     _userGesturesInProgress -= 1;
     if (_userGesturesInProgress == 0) {
-      for (NavigatorObserver observer in widget.observers)
+      for (final NavigatorObserver observer in widget.observers)
         observer.didStopUserGesture();
     }
   }
diff --git a/packages/flutter/lib/src/widgets/nested_scroll_view.dart b/packages/flutter/lib/src/widgets/nested_scroll_view.dart
index 213f85c6d67..f7397dfa527 100644
--- a/packages/flutter/lib/src/widgets/nested_scroll_view.dart
+++ b/packages/flutter/lib/src/widgets/nested_scroll_view.dart
@@ -497,7 +497,7 @@ class _NestedScrollCoordinator implements ScrollActivityDelegate, ScrollHoldCont
   }
 
   bool get hasScrolledBody {
-    for (_NestedScrollPosition position in _innerPositions) {
+    for (final _NestedScrollPosition position in _innerPositions) {
       assert(position.minScrollExtent != null && position.pixels != null);
       if (position.pixels > position.minScrollExtent) {
         return true;
@@ -520,7 +520,7 @@ class _NestedScrollCoordinator implements ScrollActivityDelegate, ScrollHoldCont
       return;
     _userScrollDirection = value;
     _outerPosition.didUpdateScrollDirection(value);
-    for (_NestedScrollPosition position in _innerPositions)
+    for (final _NestedScrollPosition position in _innerPositions)
       position.didUpdateScrollDirection(value);
   }
 
@@ -529,7 +529,7 @@ class _NestedScrollCoordinator implements ScrollActivityDelegate, ScrollHoldCont
   void beginActivity(ScrollActivity newOuterActivity, _NestedScrollActivityGetter innerActivityGetter) {
     _outerPosition.beginActivity(newOuterActivity);
     bool scrolling = newOuterActivity.isScrolling;
-    for (_NestedScrollPosition position in _innerPositions) {
+    for (final _NestedScrollPosition position in _innerPositions) {
       final ScrollActivity newInnerActivity = innerActivityGetter(position);
       position.beginActivity(newInnerActivity);
       scrolling = scrolling && newInnerActivity.isScrolling;
@@ -574,7 +574,7 @@ class _NestedScrollCoordinator implements ScrollActivityDelegate, ScrollHoldCont
     // are heading towards.
     _NestedScrollPosition innerPosition;
     if (velocity != 0.0) {
-      for (_NestedScrollPosition position in _innerPositions) {
+      for (final _NestedScrollPosition position in _innerPositions) {
         if (innerPosition != null) {
           if (velocity > 0.0) {
             if (innerPosition.pixels < position.pixels)
@@ -707,7 +707,7 @@ class _NestedScrollCoordinator implements ScrollActivityDelegate, ScrollHoldCont
     if (!_outerPosition.haveDimensions)
       return;
     double maxInnerExtent = 0.0;
-    for (_NestedScrollPosition position in _innerPositions) {
+    for (final _NestedScrollPosition position in _innerPositions) {
       if (!position.haveDimensions)
         return;
       maxInnerExtent = math.max(maxInnerExtent, position.maxScrollExtent - position.minScrollExtent);
@@ -744,7 +744,7 @@ class _NestedScrollCoordinator implements ScrollActivityDelegate, ScrollHoldCont
   void jumpTo(double to) {
     goIdle();
     _outerPosition.localJumpTo(nestOffset(to, _outerPosition));
-    for (_NestedScrollPosition position in _innerPositions)
+    for (final _NestedScrollPosition position in _innerPositions)
       position.localJumpTo(nestOffset(to, position));
     goBallistic(0.0);
   }
@@ -799,7 +799,7 @@ class _NestedScrollCoordinator implements ScrollActivityDelegate, ScrollHoldCont
       // different levels of overscroll.
       final double innerDelta = _outerPosition.applyClampedDragUpdate(delta);
       if (innerDelta != 0.0) {
-        for (_NestedScrollPosition position in _innerPositions)
+        for (final _NestedScrollPosition position in _innerPositions)
           position.applyFullDragUpdate(innerDelta);
       }
     } else {
@@ -808,7 +808,7 @@ class _NestedScrollCoordinator implements ScrollActivityDelegate, ScrollHoldCont
       double outerDelta = 0.0; // it will go positive if it changes
       final List<double> overscrolls = <double>[];
       final List<_NestedScrollPosition> innerPositions = _innerPositions.toList();
-      for (_NestedScrollPosition position in innerPositions) {
+      for (final _NestedScrollPosition position in innerPositions) {
         final double overscroll = position.applyClampedDragUpdate(delta);
         outerDelta = math.max(outerDelta, overscroll);
         overscrolls.add(overscroll);
diff --git a/packages/flutter/lib/src/widgets/overlay.dart b/packages/flutter/lib/src/widgets/overlay.dart
index 39b7e57e4b9..ec6bc13c30b 100644
--- a/packages/flutter/lib/src/widgets/overlay.dart
+++ b/packages/flutter/lib/src/widgets/overlay.dart
@@ -337,7 +337,7 @@ class OverlayState extends State<Overlay> with TickerProviderStateMixin {
     );
     if (entries.isEmpty)
       return;
-    for (OverlayEntry entry in entries) {
+    for (final OverlayEntry entry in entries) {
       assert(entry._overlay == null);
       entry._overlay = this;
     }
@@ -390,7 +390,7 @@ class OverlayState extends State<Overlay> with TickerProviderStateMixin {
     if (listEquals(_entries, newEntriesList))
       return;
     final LinkedHashSet<OverlayEntry> old = LinkedHashSet<OverlayEntry>.from(_entries);
-    for (OverlayEntry entry in newEntriesList) {
+    for (final OverlayEntry entry in newEntriesList) {
       entry._overlay ??= this;
     }
     setState(() {
@@ -561,7 +561,7 @@ class _TheatreElement extends RenderObjectElement {
   void visitChildren(ElementVisitor visitor) {
     if (_onstage != null)
       visitor(_onstage);
-    for (Element child in _offstage) {
+    for (final Element child in _offstage) {
       if (!_forgottenOffstageChildren.contains(child))
         visitor(child);
     }
diff --git a/packages/flutter/lib/src/widgets/routes.dart b/packages/flutter/lib/src/widgets/routes.dart
index 850b30b8daa..18ba06c7500 100644
--- a/packages/flutter/lib/src/widgets/routes.dart
+++ b/packages/flutter/lib/src/widgets/routes.dart
@@ -68,7 +68,7 @@ abstract class OverlayRoute<T> extends Route<T> {
 
   @override
   void dispose() {
-    for (OverlayEntry entry in _overlayEntries)
+    for (final OverlayEntry entry in _overlayEntries)
       entry.remove();
     _overlayEntries.clear();
     super.dispose();
@@ -1131,7 +1131,7 @@ abstract class ModalRoute<T> extends TransitionRoute<T> with LocalHistoryRoute<T
   Future<RoutePopDisposition> willPop() async {
     final _ModalScopeState<T> scope = _scopeKey.currentState;
     assert(scope != null);
-    for (WillPopCallback callback in List<WillPopCallback>.from(_willPopCallbacks)) {
+    for (final WillPopCallback callback in List<WillPopCallback>.from(_willPopCallbacks)) {
       if (!await callback())
         return RoutePopDisposition.doNotPop;
     }
@@ -1446,7 +1446,7 @@ class RouteObserver<R extends Route<dynamic>> extends NavigatorObserver {
   /// subscribed to multiple types, this will unregister it (once) from each type.
   void unsubscribe(RouteAware routeAware) {
     assert(routeAware != null);
-    for (R route in _listeners.keys) {
+    for (final R route in _listeners.keys) {
       final Set<RouteAware> subscribers = _listeners[route];
       subscribers?.remove(routeAware);
     }
@@ -1458,7 +1458,7 @@ class RouteObserver<R extends Route<dynamic>> extends NavigatorObserver {
       final List<RouteAware> previousSubscribers = _listeners[previousRoute]?.toList();
 
       if (previousSubscribers != null) {
-        for (RouteAware routeAware in previousSubscribers) {
+        for (final RouteAware routeAware in previousSubscribers) {
           routeAware.didPopNext();
         }
       }
@@ -1466,7 +1466,7 @@ class RouteObserver<R extends Route<dynamic>> extends NavigatorObserver {
       final List<RouteAware> subscribers = _listeners[route]?.toList();
 
       if (subscribers != null) {
-        for (RouteAware routeAware in subscribers) {
+        for (final RouteAware routeAware in subscribers) {
           routeAware.didPop();
         }
       }
@@ -1479,7 +1479,7 @@ class RouteObserver<R extends Route<dynamic>> extends NavigatorObserver {
       final Set<RouteAware> previousSubscribers = _listeners[previousRoute];
 
       if (previousSubscribers != null) {
-        for (RouteAware routeAware in previousSubscribers) {
+        for (final RouteAware routeAware in previousSubscribers) {
           routeAware.didPushNext();
         }
       }
diff --git a/packages/flutter/lib/src/widgets/scroll_controller.dart b/packages/flutter/lib/src/widgets/scroll_controller.dart
index 88fdb31a3aa..35c1b1f06e1 100644
--- a/packages/flutter/lib/src/widgets/scroll_controller.dart
+++ b/packages/flutter/lib/src/widgets/scroll_controller.dart
@@ -168,7 +168,7 @@ class ScrollController extends ChangeNotifier {
   /// value was out of range.
   void jumpTo(double value) {
     assert(_positions.isNotEmpty, 'ScrollController not attached to any scroll views.');
-    for (ScrollPosition position in List<ScrollPosition>.from(_positions))
+    for (final ScrollPosition position in List<ScrollPosition>.from(_positions))
       position.jumpTo(value);
   }
 
@@ -194,7 +194,7 @@ class ScrollController extends ChangeNotifier {
 
   @override
   void dispose() {
-    for (ScrollPosition position in _positions)
+    for (final ScrollPosition position in _positions)
       position.removeListener(notifyListeners);
     super.dispose();
   }
@@ -367,7 +367,7 @@ class TrackingScrollController extends ScrollController {
 
   @override
   void dispose() {
-    for (ScrollPosition position in positions) {
+    for (final ScrollPosition position in positions) {
       assert(_positionToListener.containsKey(position));
       position.removeListener(_positionToListener[position]);
     }
diff --git a/packages/flutter/lib/src/widgets/scrollable.dart b/packages/flutter/lib/src/widgets/scrollable.dart
index 193d8be22e6..cbf6de687f2 100644
--- a/packages/flutter/lib/src/widgets/scrollable.dart
+++ b/packages/flutter/lib/src/widgets/scrollable.dart
@@ -763,7 +763,7 @@ class _RenderScrollSemantics extends RenderProxyBox {
     int firstVisibleIndex;
     final List<SemanticsNode> excluded = <SemanticsNode>[_innerNode];
     final List<SemanticsNode> included = <SemanticsNode>[];
-    for (SemanticsNode child in children) {
+    for (final SemanticsNode child in children) {
       assert(child.isTagged(RenderViewport.useTwoPaneSemantics));
       if (child.isTagged(RenderViewport.excludeFromScrolling)) {
         excluded.add(child);
diff --git a/packages/flutter/lib/src/widgets/shortcuts.dart b/packages/flutter/lib/src/widgets/shortcuts.dart
index f34e0f611d0..351ef1137b1 100644
--- a/packages/flutter/lib/src/widgets/shortcuts.dart
+++ b/packages/flutter/lib/src/widgets/shortcuts.dart
@@ -196,7 +196,7 @@ class ShortcutManager extends ChangeNotifier with DiagnosticableMixin {
       // have synonyms in the map.  This is for things like left and right shift
       // keys mapping to just the "shift" pseudo-key.
       final Set<LogicalKeyboardKey> pseudoKeys = <LogicalKeyboardKey>{};
-      for (LogicalKeyboardKey setKey in keySet.keys) {
+      for (final LogicalKeyboardKey setKey in keySet.keys) {
         final Set<LogicalKeyboardKey> synonyms = setKey.synonyms;
         if (synonyms.isNotEmpty) {
           // There currently aren't any synonyms that match more than one key.
diff --git a/packages/flutter/lib/src/widgets/sliver.dart b/packages/flutter/lib/src/widgets/sliver.dart
index 9b4a89ce167..92fe47f9a69 100644
--- a/packages/flutter/lib/src/widgets/sliver.dart
+++ b/packages/flutter/lib/src/widgets/sliver.dart
@@ -1229,7 +1229,7 @@ class SliverMultiBoxAdaptorElement extends RenderObjectElement implements Render
         }
       }
 
-      for (int index in _childElements.keys.toList()) {
+      for (final int index in _childElements.keys.toList()) {
         final Key key = _childElements[index].widget.key;
         final int newIndex = key == null ? null : widget.delegate.findIndexByKey(key);
         if (newIndex != null && newIndex != index) {
diff --git a/packages/flutter/lib/src/widgets/table.dart b/packages/flutter/lib/src/widgets/table.dart
index 3eec4b717d6..965a70a06df 100644
--- a/packages/flutter/lib/src/widgets/table.dart
+++ b/packages/flutter/lib/src/widgets/table.dart
@@ -285,7 +285,7 @@ class _TableElement extends RenderObjectElement {
   @override
   void update(Table newWidget) {
     final Map<LocalKey, List<Element>> oldKeyedRows = <LocalKey, List<Element>>{};
-    for (_TableElementRow row in _children) {
+    for (final _TableElementRow row in _children) {
       if (row.key != null) {
         oldKeyedRows[row.key] = row.children;
       }
@@ -293,7 +293,7 @@ class _TableElement extends RenderObjectElement {
     final Iterator<_TableElementRow> oldUnkeyedRows = _children.where((_TableElementRow row) => row.key == null).iterator;
     final List<_TableElementRow> newChildren = <_TableElementRow>[];
     final Set<List<Element>> taken = <List<Element>>{};
-    for (TableRow row in newWidget.children) {
+    for (final TableRow row in newWidget.children) {
       List<Element> oldChildren;
       if (row.key != null && oldKeyedRows.containsKey(row.key)) {
         oldChildren = oldKeyedRows[row.key];
@@ -310,7 +310,7 @@ class _TableElement extends RenderObjectElement {
     }
     while (oldUnkeyedRows.moveNext())
       updateChildren(oldUnkeyedRows.current.children, const <Widget>[], forgottenChildren: _forgottenChildren);
-    for (List<Element> oldChildren in oldKeyedRows.values.where((List<Element> list) => !taken.contains(list)))
+    for (final List<Element> oldChildren in oldKeyedRows.values.where((List<Element> list) => !taken.contains(list)))
       updateChildren(oldChildren, const <Widget>[], forgottenChildren: _forgottenChildren);
 
     _children = newChildren;
@@ -335,7 +335,7 @@ class _TableElement extends RenderObjectElement {
 
   @override
   void visitChildren(ElementVisitor visitor) {
-    for (Element child in _children.expand<Element>((_TableElementRow row) => row.children)) {
+    for (final Element child in _children.expand<Element>((_TableElementRow row) => row.children)) {
       if (!_forgottenChildren.contains(child))
         visitor(child);
     }
diff --git a/packages/flutter/lib/src/widgets/ticker_provider.dart b/packages/flutter/lib/src/widgets/ticker_provider.dart
index 392ac563c90..65a825431ac 100644
--- a/packages/flutter/lib/src/widgets/ticker_provider.dart
+++ b/packages/flutter/lib/src/widgets/ticker_provider.dart
@@ -180,7 +180,7 @@ mixin TickerProviderStateMixin<T extends StatefulWidget> on State<T> implements
   void dispose() {
     assert(() {
       if (_tickers != null) {
-        for (Ticker ticker in _tickers) {
+        for (final Ticker ticker in _tickers) {
           if (ticker.isActive) {
             throw FlutterError.fromParts(<DiagnosticsNode>[
               ErrorSummary('$this was disposed with an active Ticker.'),
@@ -208,7 +208,7 @@ mixin TickerProviderStateMixin<T extends StatefulWidget> on State<T> implements
   void didChangeDependencies() {
     final bool muted = !TickerMode.of(context);
     if (_tickers != null) {
-      for (Ticker ticker in _tickers) {
+      for (final Ticker ticker in _tickers) {
         ticker.muted = muted;
       }
     }
diff --git a/packages/flutter/lib/src/widgets/widget_inspector.dart b/packages/flutter/lib/src/widgets/widget_inspector.dart
index cff08a15a80..d113c750e92 100644
--- a/packages/flutter/lib/src/widgets/widget_inspector.dart
+++ b/packages/flutter/lib/src/widgets/widget_inspector.dart
@@ -1440,7 +1440,7 @@ mixin WidgetInspectorService {
       // https://github.com/flutter/flutter/issues/32660 is fixed.
       return !file.contains('packages/flutter/');
     }
-    for (String directory in _pubRootDirectories) {
+    for (final String directory in _pubRootDirectories) {
       if (file.startsWith(directory)) {
         return true;
       }
@@ -1573,7 +1573,7 @@ mixin WidgetInspectorService {
     InspectorSerializationDelegate delegate,
   ) {
     final List<DiagnosticsNode> children = <DiagnosticsNode>[
-      for (DiagnosticsNode child in nodes)
+      for (final DiagnosticsNode child in nodes)
         if (!delegate.summaryTree || _shouldShowInSummaryTree(child))
           child
         else
@@ -1781,7 +1781,7 @@ mixin WidgetInspectorService {
     Element current = selection?.currentElement;
     if (current != null && !_isValueCreatedByLocalProject(current)) {
       Element firstLocal;
-      for (Element candidate in current.debugGetDiagnosticChain()) {
+      for (final Element candidate in current.debugGetDiagnosticChain()) {
         if (_isValueCreatedByLocalProject(candidate)) {
           firstLocal = candidate;
           break;
@@ -2003,7 +2003,7 @@ class _ElementLocationStatsTracker {
     // trigger significant additional memory allocations. Avoiding memory
     // allocations is important to minimize the impact this class has on cpu
     // and memory performance of the running app.
-    for (_LocationCount entry in active) {
+    for (final _LocationCount entry in active) {
       entry.reset();
     }
     active.clear();
@@ -2014,7 +2014,7 @@ class _ElementLocationStatsTracker {
   Map<String, dynamic> exportToJson(Duration startTime) {
     final List<int> events = List<int>.filled(active.length * 2, 0);
     int j = 0;
-    for (_LocationCount stat in active) {
+    for (final _LocationCount stat in active) {
       events[j++] = stat.id;
       events[j++] = stat.count;
     }
@@ -2027,7 +2027,7 @@ class _ElementLocationStatsTracker {
     if (newLocations.isNotEmpty) {
       // Add all newly used location ids to the JSON.
       final Map<String, List<int>> locationsJson = <String, List<int>>{};
-      for (_LocationCount entry in newLocations) {
+      for (final _LocationCount entry in newLocations) {
         final _Location location = entry.location;
         final List<int> jsonForFile = locationsJson.putIfAbsent(
           location.file,
@@ -2537,7 +2537,7 @@ class _InspectorOverlayLayer extends Layer {
 
     final RenderObject selected = selection.current;
     final List<_TransformedRect> candidates = <_TransformedRect>[];
-    for (RenderObject candidate in selection.candidates) {
+    for (final RenderObject candidate in selection.candidates) {
       if (candidate == selected || !candidate.attached)
         continue;
       candidates.add(_TransformedRect(candidate));
@@ -2584,7 +2584,7 @@ class _InspectorOverlayLayer extends Layer {
     // Show all other candidate possibly selected elements. This helps selecting
     // render objects by selecting the edge of the bounding box shows all
     // elements the user could toggle the selection between.
-    for (_TransformedRect transformedRect in state.candidates) {
+    for (final _TransformedRect transformedRect in state.candidates) {
       canvas
         ..save()
         ..transform(transformedRect.transform.storage)
@@ -2767,7 +2767,7 @@ bool _isDebugCreator(DiagnosticsNode node) => node is DiagnosticsDebugCreator;
 Iterable<DiagnosticsNode> transformDebugCreator(Iterable<DiagnosticsNode> properties) sync* {
   final List<DiagnosticsNode> pending = <DiagnosticsNode>[];
   bool foundStackTrace = false;
-  for (DiagnosticsNode node in properties) {
+  for (final DiagnosticsNode node in properties) {
     if (!foundStackTrace && node is DiagnosticsStackTrace)
       foundStackTrace = true;
     if (_isDebugCreator(node)) {
diff --git a/packages/flutter/test/foundation/diagnostics_json_test.dart b/packages/flutter/test/foundation/diagnostics_json_test.dart
index e03599490f3..4a52f77cd83 100644
--- a/packages/flutter/test/foundation/diagnostics_json_test.dart
+++ b/packages/flutter/test/foundation/diagnostics_json_test.dart
@@ -247,7 +247,7 @@ class TestTree extends Object with DiagnosticableTreeMixin {
 
   @override
   List<DiagnosticsNode> debugDescribeChildren() => <DiagnosticsNode>[
-    for (TestTree child in children)
+    for (final TestTree child in children)
       child.toDiagnosticsNode(
         name: 'child ${child.name}',
         style: child.style,
diff --git a/packages/flutter/test/foundation/diagnostics_test.dart b/packages/flutter/test/foundation/diagnostics_test.dart
index 09246b79c35..2ab97c8be9d 100644
--- a/packages/flutter/test/foundation/diagnostics_test.dart
+++ b/packages/flutter/test/foundation/diagnostics_test.dart
@@ -23,7 +23,7 @@ class TestTree extends Object with DiagnosticableTreeMixin {
 
   @override
   List<DiagnosticsNode> debugDescribeChildren() => <DiagnosticsNode>[
-    for (TestTree child in children)
+    for (final TestTree child in children)
       child.toDiagnosticsNode(
         name: 'child ${child.name}',
         style: child.style,
diff --git a/packages/flutter/test/gestures/gesture_binding_test.dart b/packages/flutter/test/gestures/gesture_binding_test.dart
index 1bd207d86de..41574f10728 100644
--- a/packages/flutter/test/gestures/gesture_binding_test.dart
+++ b/packages/flutter/test/gestures/gesture_binding_test.dart
@@ -205,7 +205,7 @@ void main() {
 
   test('Should synthesize kPrimaryButton for stylus', () {
     final Offset location = const Offset(10.0, 10.0) * ui.window.devicePixelRatio;
-    for (PointerDeviceKind kind in <PointerDeviceKind>[
+    for (final PointerDeviceKind kind in <PointerDeviceKind>[
       PointerDeviceKind.stylus,
       PointerDeviceKind.invertedStylus,
     ]) {
@@ -268,7 +268,7 @@ void main() {
 
   test('Should not synthesize kPrimaryButton for mouse', () {
     final Offset location = const Offset(10.0, 10.0) * ui.window.devicePixelRatio;
-    for (PointerDeviceKind kind in <PointerDeviceKind>[
+    for (final PointerDeviceKind kind in <PointerDeviceKind>[
       PointerDeviceKind.mouse,
     ]) {
       final ui.PointerDataPacket packet = ui.PointerDataPacket(
diff --git a/packages/flutter/test/gestures/velocity_tracker_test.dart b/packages/flutter/test/gestures/velocity_tracker_test.dart
index b1e4c320041..803286738e5 100644
--- a/packages/flutter/test/gestures/velocity_tracker_test.dart
+++ b/packages/flutter/test/gestures/velocity_tracker_test.dart
@@ -38,7 +38,7 @@ void main() {
   test('Velocity tracker gives expected results', () {
     final VelocityTracker tracker = VelocityTracker();
     int i = 0;
-    for (PointerEvent event in velocityEventData) {
+    for (final PointerEvent event in velocityEventData) {
       if (event is PointerDownEvent || event is PointerMoveEvent)
         tracker.addPosition(event.timeStamp, event.position);
       if (event is PointerUpEvent) {
@@ -63,7 +63,7 @@ void main() {
   test('Interrupted velocity estimation', () {
     // Regression test for https://github.com/flutter/flutter/pull/7510
     final VelocityTracker tracker = VelocityTracker();
-    for (PointerEvent event in interruptedVelocityEventData) {
+    for (final PointerEvent event in interruptedVelocityEventData) {
       if (event is PointerDownEvent || event is PointerMoveEvent)
         tracker.addPosition(event.timeStamp, event.position);
       if (event is PointerUpEvent) {
diff --git a/packages/flutter/test/material/colors_test.dart b/packages/flutter/test/material/colors_test.dart
index d0e4209c047..a9f33bbcb53 100644
--- a/packages/flutter/test/material/colors_test.dart
+++ b/packages/flutter/test/material/colors_test.dart
@@ -53,31 +53,31 @@ void main() {
   });
 
   test('Colors swatches do not contain duplicates', () {
-    for (MaterialColor color in Colors.primaries)
+    for (final MaterialColor color in Colors.primaries)
       expect(primaryKeys.map<Color>((int key) => color[key]).toSet().length, primaryKeys.length);
 
     expect(primaryKeys.map<Color>((int key) => Colors.grey[key]).toSet().length, primaryKeys.length);
 
-    for (MaterialAccentColor color in Colors.accents)
+    for (final MaterialAccentColor color in Colors.accents)
       expect(accentKeys.map<Color>((int key) => color[key]).toSet().length, accentKeys.length);
   });
 
   test('All color swatch colors are opaque and equal their primary color', () {
-    for (MaterialColor color in Colors.primaries) {
+    for (final MaterialColor color in Colors.primaries) {
       expect(color.value, color.shade500.value);
-      for (int key in primaryKeys) {
+      for (final int key in primaryKeys) {
         expect(color[key].alpha, 0xFF);
       }
     }
 
     expect(Colors.grey.value, Colors.grey.shade500.value);
-    for (int key in primaryKeys) {
+    for (final int key in primaryKeys) {
       expect(Colors.grey[key].alpha, 0xFF);
     }
 
-    for (MaterialAccentColor color in Colors.accents) {
+    for (final MaterialAccentColor color in Colors.accents) {
       expect(color.value, color.shade200.value);
-      for (int key in accentKeys) {
+      for (final int key in accentKeys) {
         expect(color[key].alpha, 0xFF);
       }
     }
diff --git a/packages/flutter/test/material/date_picker_test.dart b/packages/flutter/test/material/date_picker_test.dart
index b2cd46b8c45..7b683c8db7c 100644
--- a/packages/flutter/test/material/date_picker_test.dart
+++ b/packages/flutter/test/material/date_picker_test.dart
@@ -742,7 +742,7 @@ void _tests() {
 
     // Initial chevron animation state should be dismissed
     // An AlwaysStoppedAnimation is also found and is ignored
-    for (RenderAnimatedOpacity renderer in chevronRenderers) {
+    for (final RenderAnimatedOpacity renderer in chevronRenderers) {
       expect(renderer.opacity.value, equals(1.0));
       expect(renderer.opacity.status, equals(AnimationStatus.dismissed));
     }
@@ -751,7 +751,7 @@ void _tests() {
     final TestGesture gesture = await tester.startGesture(const Offset(100.0, 100.0));
     await gesture.moveBy(const Offset(50.0, 100.0));
     await tester.pumpAndSettle();
-    for (RenderAnimatedOpacity renderer in chevronRenderers) {
+    for (final RenderAnimatedOpacity renderer in chevronRenderers) {
       expect(renderer.opacity.value, equals(0.0));
       expect(renderer.opacity.status, equals(AnimationStatus.completed));
     }
@@ -759,7 +759,7 @@ void _tests() {
     // Release the drag and test for the opacity to return to original value
     await gesture.up();
     await tester.pumpAndSettle();
-    for (RenderAnimatedOpacity renderer in chevronRenderers) {
+    for (final RenderAnimatedOpacity renderer in chevronRenderers) {
       expect(renderer.opacity.value, equals(1.0));
       expect(renderer.opacity.status, equals(AnimationStatus.dismissed));
     }
diff --git a/packages/flutter/test/material/dropdown_form_field_test.dart b/packages/flutter/test/material/dropdown_form_field_test.dart
index ef98d30f587..5ad34d7d8b1 100644
--- a/packages/flutter/test/material/dropdown_form_field_test.dart
+++ b/packages/flutter/test/material/dropdown_form_field_test.dart
@@ -264,7 +264,7 @@ void main() {
     final double menuItemHeight = itemBoxesHeight.reduce(math.max);
     expect(menuItemHeight, greaterThanOrEqualTo(buttonBox.size.height));
 
-    for (RenderBox itemBox in itemBoxes) {
+    for (final RenderBox itemBox in itemBoxes) {
       expect(itemBox.attached, isTrue);
       final Offset buttonBoxCenter = buttonBox.size.center(buttonBox.localToGlobal(Offset.zero));
       final Offset itemBoxCenter = itemBox.size.center(itemBox.localToGlobal(Offset.zero));
diff --git a/packages/flutter/test/material/dropdown_test.dart b/packages/flutter/test/material/dropdown_test.dart
index b8c6e81d04a..795822c42c4 100644
--- a/packages/flutter/test/material/dropdown_test.dart
+++ b/packages/flutter/test/material/dropdown_test.dart
@@ -447,7 +447,7 @@ void main() {
     await tester.pump(const Duration(seconds: 1)); // finish the menu animation
   });
 
-  for (TextDirection textDirection in TextDirection.values) {
+  for (final TextDirection textDirection in TextDirection.values) {
     testWidgets('Dropdown button aligns selected menu item ($textDirection)', (WidgetTester tester) async {
       final Key buttonKey = UniqueKey();
       const String value = 'two';
@@ -471,7 +471,7 @@ void main() {
       // have the same origin and height as the dropdown button.
       final List<RenderBox> itemBoxes = tester.renderObjectList<RenderBox>(find.byKey(const ValueKey<String>('two'))).toList();
       expect(itemBoxes.length, equals(2));
-      for (RenderBox itemBox in itemBoxes) {
+      for (final RenderBox itemBox in itemBoxes) {
         assert(itemBox.attached);
         assert(textDirection != null);
         switch (textDirection) {
@@ -664,7 +664,7 @@ void main() {
     final double menuItemHeight = itemBoxes.map<double>((RenderBox box) => box.size.height).reduce(math.max);
     expect(menuItemHeight, greaterThan(buttonBox.size.height));
 
-    for (RenderBox itemBox in itemBoxes) {
+    for (final RenderBox itemBox in itemBoxes) {
       assert(itemBox.attached);
       final Offset buttonBoxCenter = buttonBox.size.center(buttonBox.localToGlobal(Offset.zero));
       final Offset itemBoxCenter = itemBox.size.center(itemBox.localToGlobal(Offset.zero));
diff --git a/packages/flutter/test/material/floating_action_button_location_test.dart b/packages/flutter/test/material/floating_action_button_location_test.dart
index e898bb5dbb9..264e7197b9b 100644
--- a/packages/flutter/test/material/floating_action_button_location_test.dart
+++ b/packages/flutter/test/material/floating_action_button_location_test.dart
@@ -137,9 +137,9 @@ void main() {
               && currentRotations != null && currentRotations.isNotEmpty
               && previousRect != null && currentRect != null) {
             final List<double> deltas = <double>[];
-            for (double currentRotation in currentRotations) {
+            for (final double currentRotation in currentRotations) {
               double minDelta;
-              for (double previousRotation in previousRotations) {
+              for (final double previousRotation in previousRotations) {
                 final double delta = (previousRotation - currentRotation).abs();
                 minDelta ??= delta;
                 minDelta = min(delta, minDelta);
diff --git a/packages/flutter/test/material/material_test.dart b/packages/flutter/test/material/material_test.dart
index a862fd4d304..c48b3b7911d 100644
--- a/packages/flutter/test/material/material_test.dart
+++ b/packages/flutter/test/material/material_test.dart
@@ -251,7 +251,7 @@ void main() {
         ElevationColor(24.0, Color(0xFF20362B)),
       ];
 
-      for (ElevationColor test in elevationColors) {
+      for (final ElevationColor test in elevationColors) {
         await tester.pumpWidget(
             Theme(
               data: ThemeData(
diff --git a/packages/flutter/test/material/page_selector_test.dart b/packages/flutter/test/material/page_selector_test.dart
index 43be2d76c8c..35e24dc375c 100644
--- a/packages/flutter/test/material/page_selector_test.dart
+++ b/packages/flutter/test/material/page_selector_test.dart
@@ -212,7 +212,7 @@ void main() {
     ).evaluate();
 
     // Indicators get an 8 pixel margin, 16 + 8 = 24.
-    for (Element indicatorElement in indicatorElements)
+    for (final Element indicatorElement in indicatorElements)
       expect(indicatorElement.size, const Size(24.0, 24.0));
 
     expect(tester.getSize(find.byType(TabPageSelector)).height, 24.0);
diff --git a/packages/flutter/test/material/reorderable_list_test.dart b/packages/flutter/test/material/reorderable_list_test.dart
index 8ae34726122..94568e84a96 100644
--- a/packages/flutter/test/material/reorderable_list_test.dart
+++ b/packages/flutter/test/material/reorderable_list_test.dart
@@ -316,7 +316,7 @@ void main() {
         testWidgets('Provides the correct accessibility actions in LTR and RTL modes', (WidgetTester tester) async {
           // The a11y actions for a vertical list are the same in LTR and RTL modes.
           final SemanticsHandle handle = tester.ensureSemantics();
-          for (TextDirection direction in TextDirection.values) {
+          for (final TextDirection direction in TextDirection.values) {
             await tester.pumpWidget(build());
 
             // The first item can be moved down or to the end.
diff --git a/packages/flutter/test/material/theme_data_test.dart b/packages/flutter/test/material/theme_data_test.dart
index fbad907149a..041ed51daf5 100644
--- a/packages/flutter/test/material/theme_data_test.dart
+++ b/packages/flutter/test/material/theme_data_test.dart
@@ -21,7 +21,7 @@ void main() {
   });
 
   test('Defaults to the default typography for the platform', () {
-    for (TargetPlatform platform in TargetPlatform.values) {
+    for (final TargetPlatform platform in TargetPlatform.values) {
       final ThemeData theme = ThemeData(platform: platform);
       final Typography typography = Typography(platform: platform);
       expect(theme.textTheme, typography.black.apply(decoration: TextDecoration.none),
diff --git a/packages/flutter/test/material/theme_test.dart b/packages/flutter/test/material/theme_test.dart
index dd9513c1754..837ec1aaa86 100644
--- a/packages/flutter/test/material/theme_test.dart
+++ b/packages/flutter/test/material/theme_test.dart
@@ -148,7 +148,7 @@ void main() {
     await tester.tap(find.byKey(dropdownMenuButtonKey));
     await tester.pump(const Duration(seconds: 1));
 
-    for (Element item in tester.elementList(find.text('menuItem')))
+    for (final Element item in tester.elementList(find.text('menuItem')))
       expect(Theme.of(item).brightness, equals(Brightness.light));
   });
 
@@ -390,8 +390,8 @@ void main() {
       ];
     }
 
-    for (TextTheme textTheme in <TextTheme>[theme.textTheme, theme.primaryTextTheme, theme.accentTextTheme]) {
-      for (TextStyle style in extractStyles(textTheme).map<TextStyle>((TextStyle style) => _TextStyleProxy(style))) {
+    for (final TextTheme textTheme in <TextTheme>[theme.textTheme, theme.primaryTextTheme, theme.accentTextTheme]) {
+      for (final TextStyle style in extractStyles(textTheme).map<TextStyle>((TextStyle style) => _TextStyleProxy(style))) {
         expect(style.inherit, false);
         expect(style.color, isNotNull);
         expect(style.fontFamily, isNotNull);
diff --git a/packages/flutter/test/material/time_picker_test.dart b/packages/flutter/test/material/time_picker_test.dart
index 4be6efdcc19..d5a4d439cb7 100644
--- a/packages/flutter/test/material/time_picker_test.dart
+++ b/packages/flutter/test/material/time_picker_test.dart
@@ -734,7 +734,7 @@ class _CustomPainterSemanticsTester {
     final PaintPattern expectedLabels = paints;
     int i = 0;
 
-    for (_SemanticsNodeExpectation expectation in expectedNodes) {
+    for (final _SemanticsNodeExpectation expectation in expectedNodes) {
       expect(semantics, includesNodeWith(value: expectation.label));
       final Iterable<SemanticsNode> dialLabelNodes = semantics
           .nodesWith(value: expectation.label)
diff --git a/packages/flutter/test/material/typography_test.dart b/packages/flutter/test/material/typography_test.dart
index c4c642d9365..726f2c4de99 100644
--- a/packages/flutter/test/material/typography_test.dart
+++ b/packages/flutter/test/material/typography_test.dart
@@ -8,7 +8,7 @@ import 'package:flutter_test/flutter_test.dart';
 
 void main() {
   test('Typography is defined for all target platforms', () {
-    for (TargetPlatform platform in TargetPlatform.values) {
+    for (final TargetPlatform platform in TargetPlatform.values) {
       final Typography typography = Typography(platform: platform);
       expect(typography, isNotNull, reason: 'null typography for $platform');
       expect(typography.black, isNotNull, reason: 'null black typography for $platform');
@@ -32,7 +32,7 @@ void main() {
     }, 'Uses SF Text font');
 
     final Typography typography = Typography(platform: TargetPlatform.iOS);
-    for (TextTheme textTheme in <TextTheme>[typography.black, typography.white]) {
+    for (final TextTheme textTheme in <TextTheme>[typography.black, typography.white]) {
       expect(textTheme.display4, isDisplayFont);
       expect(textTheme.display3, isDisplayFont);
       expect(textTheme.display2, isDisplayFont);
diff --git a/packages/flutter/test/painting/alignment_test.dart b/packages/flutter/test/painting/alignment_test.dart
index fd487f2ff9b..15691d677f8 100644
--- a/packages/flutter/test/painting/alignment_test.dart
+++ b/packages/flutter/test/painting/alignment_test.dart
@@ -57,14 +57,14 @@ void main() {
     expect(topEnd * 1.0, topEnd);
     expect(topLeft * 1.0, topLeft);
     expect(topRight * 1.0, topRight);
-    for (double n in numbers) {
+    for (final double n in numbers) {
       expect((topStart * n).add(topStart), topStart * (n + 1.0));
       expect((topEnd * n).add(topEnd), topEnd * (n + 1.0));
-      for (double m in numbers)
+      for (final double m in numbers)
         expect((topStart * n).add(topStart * m), topStart * (n + m));
     }
     expect(topStart + topStart + topStart, topStart * 3.0); // without using "add"
-    for (TextDirection x in TextDirection.values) {
+    for (final TextDirection x in TextDirection.values) {
       expect((topEnd * 0.0).add(topRight * 0.0).resolve(x), center.add(center).resolve(x));
       expect((topEnd * 0.0).add(topLeft).resolve(x), center.add(topLeft).resolve(x));
       expect(((topEnd * 0.0).resolve(x)).add(topLeft.resolve(x)), (center.resolve(x)).add(topLeft.resolve(x)));
@@ -107,7 +107,7 @@ void main() {
     final AlignmentGeometry mixed2 = const Alignment(70.0, 110.0).add(const AlignmentDirectional(130.0, 170.0));
     final AlignmentGeometry mixed3 = const Alignment(25.0, 42.5).add(const AlignmentDirectional(55.0, 80.0));
 
-    for (TextDirection direction in TextDirection.values) {
+    for (final TextDirection direction in TextDirection.values) {
       expect(AlignmentGeometry.lerp(mixed1, mixed2, 0.0).resolve(direction), mixed1.resolve(direction));
       expect(AlignmentGeometry.lerp(mixed1, mixed2, 1.0).resolve(direction), mixed2.resolve(direction));
       expect(AlignmentGeometry.lerp(mixed1, mixed2, 0.25).resolve(direction), mixed3.resolve(direction));
@@ -150,17 +150,17 @@ void main() {
 
     final List<double> times = <double>[ 0.25, 0.5, 0.75 ];
 
-    for (TextDirection direction in TextDirection.values) {
+    for (final TextDirection direction in TextDirection.values) {
       final Alignment defaultValue = AlignmentDirectional.center.resolve(direction);
-      for (AlignmentGeometry a in offsets) {
+      for (final AlignmentGeometry a in offsets) {
         final Alignment resolvedA = a?.resolve(direction) ?? defaultValue;
-        for (AlignmentGeometry b in offsets) {
+        for (final AlignmentGeometry b in offsets) {
           final Alignment resolvedB = b?.resolve(direction) ?? defaultValue;
           approxExpect(Alignment.lerp(resolvedA, resolvedB, 0.0), resolvedA);
           approxExpect(Alignment.lerp(resolvedA, resolvedB, 1.0), resolvedB);
           approxExpect((AlignmentGeometry.lerp(a, b, 0.0) ?? defaultValue).resolve(direction), resolvedA);
           approxExpect((AlignmentGeometry.lerp(a, b, 1.0) ?? defaultValue).resolve(direction), resolvedB);
-          for (double t in times) {
+          for (final double t in times) {
             assert(t > 0.0);
             assert(t < 1.0);
             final Alignment value = (AlignmentGeometry.lerp(a, b, t) ?? defaultValue).resolve(direction);
@@ -191,7 +191,7 @@ void main() {
     expect(const AlignmentDirectional(1.0, 2.0) / 2.0, const AlignmentDirectional(0.5, 1.0));
     expect(const AlignmentDirectional(1.0, 2.0) % 2.0, const AlignmentDirectional(1.0, 0.0));
     expect(const AlignmentDirectional(1.0, 2.0) ~/ 2.0, const AlignmentDirectional(0.0, 1.0));
-    for (TextDirection direction in TextDirection.values) {
+    for (final TextDirection direction in TextDirection.values) {
       expect(Alignment.center.add(const AlignmentDirectional(1.0, 2.0) * 2.0).resolve(direction), const AlignmentDirectional(2.0, 4.0).resolve(direction));
       expect(Alignment.center.add(const AlignmentDirectional(1.0, 2.0) / 2.0).resolve(direction), const AlignmentDirectional(0.5, 1.0).resolve(direction));
       expect(Alignment.center.add(const AlignmentDirectional(1.0, 2.0) % 2.0).resolve(direction), const AlignmentDirectional(1.0, 0.0).resolve(direction));
diff --git a/packages/flutter/test/painting/decoration_test.dart b/packages/flutter/test/painting/decoration_test.dart
index b869fee1c71..1e1b6613793 100644
--- a/packages/flutter/test/painting/decoration_test.dart
+++ b/packages/flutter/test/painting/decoration_test.dart
@@ -521,7 +521,7 @@ void main() {
       BoxFit.scaleDown,
     ];
 
-    for (BoxFit boxFit in boxFits) {
+    for (final BoxFit boxFit in boxFits) {
       final TestCanvas canvas = TestCanvas(<Invocation>[]);
 
       const Rect outputRect = Rect.fromLTWH(30.0, 30.0, 250.0, 250.0);
diff --git a/packages/flutter/test/painting/gradient_test.dart b/packages/flutter/test/painting/gradient_test.dart
index d47a1646c13..41bd3e74f73 100644
--- a/packages/flutter/test/painting/gradient_test.dart
+++ b/packages/flutter/test/painting/gradient_test.dart
@@ -814,13 +814,13 @@ void main() {
     }
 
     testWidgets('Gradients - 45 degrees', (WidgetTester tester) async {
-      for (Gradient gradient in gradients45) {
+      for (final Gradient gradient in gradients45) {
         await runTest(tester, gradient, 45);
       }
     }, skip: isBrowser); // TODO(yjbanov): web does not support golden tests yet: https://github.com/flutter/flutter/issues/40297
 
     testWidgets('Gradients - 90 degrees', (WidgetTester tester) async {
-      for (Gradient gradient in gradients90) {
+      for (final Gradient gradient in gradients90) {
         await runTest(tester, gradient, 90);
       }
     }, skip: isBrowser); // TODO(yjbanov): web does not support golden tests yet: https://github.com/flutter/flutter/issues/40297
diff --git a/packages/flutter/test/painting/text_painter_test.dart b/packages/flutter/test/painting/text_painter_test.dart
index e7063eac5d3..e2996f090fc 100644
--- a/packages/flutter/test/painting/text_painter_test.dart
+++ b/packages/flutter/test/painting/text_painter_test.dart
@@ -749,7 +749,7 @@ void main() {
     // be removed when it is no longer useful.
     if (lines[1].hardBreak == true) {
       print('LineMetrics called: ${lines.length}');
-      for (ui.LineMetrics line in lines) {
+      for (final ui.LineMetrics line in lines) {
         print('${line.lineNumber}: ${line.hardBreak}');
       }
     }
diff --git a/packages/flutter/test/rendering/annotated_region_test.dart b/packages/flutter/test/rendering/annotated_region_test.dart
index 29dc34b91b5..81f696d7f48 100644
--- a/packages/flutter/test/rendering/annotated_region_test.dart
+++ b/packages/flutter/test/rendering/annotated_region_test.dart
@@ -16,7 +16,7 @@ void main() {
         OffsetLayer(offset: const Offset(0.0, 200.0)),
       ];
       int i = 0;
-      for (OffsetLayer layer in layers) {
+      for (final OffsetLayer layer in layers) {
         layer.append(AnnotatedRegionLayer<int>(i, size: const Size(200.0, 100.0)));
         containerLayer.append(layer);
         i += 1;
@@ -35,7 +35,7 @@ void main() {
         ClipRectLayer(clipRect: const Rect.fromLTRB(0.0, 200.0, 100.0, 300.0)),
       ];
       int i = 0;
-      for (ClipRectLayer layer in layers) {
+      for (final ClipRectLayer layer in layers) {
         layer.append(AnnotatedRegionLayer<int>(i));
         containerLayer.append(layer);
         i += 1;
@@ -55,7 +55,7 @@ void main() {
         ClipRRectLayer(clipRRect: RRect.fromLTRBR(0.0, 200.0, 100.0, 300.0, const Radius.circular(4.0))),
       ];
       int i = 0;
-      for (ClipRRectLayer layer in layers) {
+      for (final ClipRRectLayer layer in layers) {
         layer.append(AnnotatedRegionLayer<int>(i));
         containerLayer.append(layer);
         i += 1;
@@ -80,7 +80,7 @@ void main() {
         OffsetLayer(offset: const Offset(0.0, 200.0)),
       ];
       int i = 0;
-      for (OffsetLayer layer in layers) {
+      for (final OffsetLayer layer in layers) {
         final AnnotatedRegionLayer<int> annotatedRegionLayer = AnnotatedRegionLayer<int>(i, size: const Size(100.0, 100.0));
         layer.append(annotatedRegionLayer);
         transformLayer.append(layer);
@@ -145,7 +145,7 @@ void main() {
         OffsetLayer(offset: const Offset(0.0, 200.0)),
       ];
       int i = 0;
-      for (OffsetLayer layer in layers) {
+      for (final OffsetLayer layer in layers) {
         layer.append(AnnotatedRegionLayer<int>(i, size: const Size(200.0, 100.0)));
         containerLayer.append(layer);
         i += 1;
@@ -164,7 +164,7 @@ void main() {
         ClipRectLayer(clipRect: const Rect.fromLTRB(0.0, 200.0, 100.0, 300.0)),
       ];
       int i = 0;
-      for (ClipRectLayer layer in layers) {
+      for (final ClipRectLayer layer in layers) {
         layer.append(AnnotatedRegionLayer<int>(i));
         containerLayer.append(layer);
         i += 1;
@@ -184,7 +184,7 @@ void main() {
         ClipRRectLayer(clipRRect: RRect.fromLTRBR(0.0, 200.0, 100.0, 300.0, const Radius.circular(4.0))),
       ];
       int i = 0;
-      for (ClipRRectLayer layer in layers) {
+      for (final ClipRRectLayer layer in layers) {
         layer.append(AnnotatedRegionLayer<int>(i));
         containerLayer.append(layer);
         i += 1;
@@ -209,7 +209,7 @@ void main() {
         OffsetLayer(offset: const Offset(0.0, 200.0)),
       ];
       int i = 0;
-      for (OffsetLayer layer in layers) {
+      for (final OffsetLayer layer in layers) {
         final AnnotatedRegionLayer<int> annotatedRegionLayer = AnnotatedRegionLayer<int>(i, size: const Size(100.0, 100.0));
         layer.append(annotatedRegionLayer);
         transformLayer.append(layer);
@@ -231,7 +231,7 @@ void main() {
         AnnotatedRegionLayer<int>(index++, size: const Size(100.0, 100.0)),
         AnnotatedRegionLayer<int>(index++, size: const Size(100.0, 100.0)),
       ];
-      for (ContainerLayer layer in layers) {
+      for (final ContainerLayer layer in layers) {
         final AnnotatedRegionLayer<int> annotatedRegionLayer = AnnotatedRegionLayer<int>(index++, size: const Size(100.0, 100.0));
         layer.append(annotatedRegionLayer);
         parent.append(layer);
diff --git a/packages/flutter/test/rendering/layer_annotations_test.dart b/packages/flutter/test/rendering/layer_annotations_test.dart
index e89da636751..b3bd5d1adbf 100644
--- a/packages/flutter/test/rendering/layer_annotations_test.dart
+++ b/packages/flutter/test/rendering/layer_annotations_test.dart
@@ -674,7 +674,7 @@ class _Layers {
     assert(!_assigned);
     _assigned = true;
     if (children != null) {
-      for (Object child in children) {
+      for (final Object child in children) {
         Layer layer;
         if (child is Layer) {
           layer = child;
diff --git a/packages/flutter/test/rendering/layers_test.dart b/packages/flutter/test/rendering/layers_test.dart
index e57b76b5c30..231e15c455e 100644
--- a/packages/flutter/test/rendering/layers_test.dart
+++ b/packages/flutter/test/rendering/layers_test.dart
@@ -113,15 +113,15 @@ void main() {
     b.append(f);
     c.append(g);
 
-    for (ContainerLayer layer in allLayers) {
+    for (final ContainerLayer layer in allLayers) {
       expect(layer.debugSubtreeNeedsAddToScene, true);
     }
 
-    for (ContainerLayer layer in allLayers) {
+    for (final ContainerLayer layer in allLayers) {
       layer.debugMarkClean();
     }
 
-    for (ContainerLayer layer in allLayers) {
+    for (final ContainerLayer layer in allLayers) {
       expect(layer.debugSubtreeNeedsAddToScene, false);
     }
 
@@ -148,7 +148,7 @@ void main() {
     expect(g.debugSubtreeNeedsAddToScene, true);
 
     a.buildScene(SceneBuilder());
-    for (ContainerLayer layer in allLayers) {
+    for (final ContainerLayer layer in allLayers) {
       expect(layer.debugSubtreeNeedsAddToScene, false);
     }
   });
diff --git a/packages/flutter/test/rendering/mock_canvas.dart b/packages/flutter/test/rendering/mock_canvas.dart
index 345187ef11d..869db0484f8 100644
--- a/packages/flutter/test/rendering/mock_canvas.dart
+++ b/packages/flutter/test/rendering/mock_canvas.dart
@@ -456,10 +456,10 @@ class _PathMatcher extends Matcher {
     }
     final Path path = object as Path;
     final List<String> errors = <String>[
-      for (Offset offset in includes)
+      for (final Offset offset in includes)
         if (!path.contains(offset))
           'Offset $offset should be inside the path, but is not.',
-      for (Offset offset in excludes)
+      for (final Offset offset in excludes)
         if (path.contains(offset))
           'Offset $offset should be outside the path, but is not.',
     ];
@@ -546,7 +546,7 @@ abstract class _TestRecordingCanvasMatcher extends Matcher {
     if (!result) {
       if (canvas.invocations.isNotEmpty) {
         description.write('The complete display list was:');
-        for (RecordedInvocation call in canvas.invocations)
+        for (final RecordedInvocation call in canvas.invocations)
           description.write('\n  * $call');
       }
       matchState[this] = '$prefixMessage\n$description';
@@ -583,7 +583,7 @@ class _TestRecordingCanvasPaintsCountMatcher extends _TestRecordingCanvasMatcher
   @override
   bool _evaluatePredicates(Iterable<RecordedInvocation> calls, StringBuffer description) {
     int count = 0;
-    for (RecordedInvocation call in calls) {
+    for (final RecordedInvocation call in calls) {
       if (call.invocation.isMethod && call.invocation.memberName == _methodName) {
         count++;
       }
@@ -651,7 +651,7 @@ class _TestRecordingCanvasPaintsAssertionMatcher extends Matcher {
     if (!result) {
       if (canvas.invocations.isNotEmpty) {
         description.write('The complete display list was:');
-        for (RecordedInvocation call in canvas.invocations)
+        for (final RecordedInvocation call in canvas.invocations)
           description.write('\n  * $call');
       }
       matchState[this] = '$prefixMessage\n$description';
@@ -1159,13 +1159,13 @@ class _PathPaintPredicate extends _DrawCommandPaintPredicate {
     super.verifyArguments(arguments);
     final Path pathArgument = arguments[0] as Path;
     if (includes != null) {
-      for (Offset offset in includes) {
+      for (final Offset offset in includes) {
         if (!pathArgument.contains(offset))
           throw 'It called $methodName with a path that unexpectedly did not contain $offset.';
       }
     }
     if (excludes != null) {
-      for (Offset offset in excludes) {
+      for (final Offset offset in excludes) {
         if (pathArgument.contains(offset))
           throw 'It called $methodName with a path that unexpectedly contained $offset.';
       }
@@ -1243,13 +1243,13 @@ class _ShadowPredicate extends _PaintPredicate {
       throw 'It called $methodName with ${arguments.length} arguments; expected 4.';
     final Path pathArgument = arguments[0] as Path;
     if (includes != null) {
-      for (Offset offset in includes) {
+      for (final Offset offset in includes) {
         if (!pathArgument.contains(offset))
           throw 'It called $methodName with a path that unexpectedly did not contain $offset.';
       }
     }
     if (excludes != null) {
-      for (Offset offset in excludes) {
+      for (final Offset offset in excludes) {
         if (pathArgument.contains(offset))
           throw 'It called $methodName with a path that unexpectedly contained $offset.';
       }
diff --git a/packages/flutter/test/rendering/slivers_helpers_test.dart b/packages/flutter/test/rendering/slivers_helpers_test.dart
index 9b30daccc88..5d942522097 100644
--- a/packages/flutter/test/rendering/slivers_helpers_test.dart
+++ b/packages/flutter/test/rendering/slivers_helpers_test.dart
@@ -8,7 +8,7 @@ import 'package:flutter_test/flutter_test.dart';
 void main() {
   test('applyGrowthDirectionToAxisDirection produces expected AxisDirection', () {
     expect(AxisDirection.values.length, 4);
-    for (AxisDirection axisDirection in AxisDirection.values) {
+    for (final AxisDirection axisDirection in AxisDirection.values) {
       expect(applyGrowthDirectionToAxisDirection(axisDirection, GrowthDirection.forward), axisDirection);
     }
     expect(applyGrowthDirectionToAxisDirection(AxisDirection.up, GrowthDirection.reverse), AxisDirection.down);
diff --git a/packages/flutter/test/rendering/table_test.dart b/packages/flutter/test/rendering/table_test.dart
index b8ac8db4d4e..0d082e1365f 100644
--- a/packages/flutter/test/rendering/table_test.dart
+++ b/packages/flutter/test/rendering/table_test.dart
@@ -55,7 +55,7 @@ void main() {
     layout(table, constraints: const BoxConstraints.tightFor(width: 100.0));
 
     const double expectedWidth = 100.0 / 6;
-    for (RenderBox child in children) {
+    for (final RenderBox child in children) {
       expect(child.size.width, moreOrLessEquals(expectedWidth));
     }
   });
diff --git a/packages/flutter/test/semantics/semantics_test.dart b/packages/flutter/test/semantics/semantics_test.dart
index c3884828c74..527c336514e 100644
--- a/packages/flutter/test/semantics/semantics_test.dart
+++ b/packages/flutter/test/semantics/semantics_test.dart
@@ -264,7 +264,7 @@ void main() {
     final List<int> expectedResults = <int>[0, -1, 1, 0];
     assert(tests.length == expectedResults.length);
     final List<int> results = <int>[
-      for (List<SemanticsSortKey> tuple in tests) tuple[0].compareTo(tuple[1]),
+      for (final List<SemanticsSortKey> tuple in tests) tuple[0].compareTo(tuple[1]),
     ];
     expect(results, orderedEquals(expectedResults));
   });
@@ -279,7 +279,7 @@ void main() {
     final List<int> expectedResults = <int>[0, -1, 1, 0];
     assert(tests.length == expectedResults.length);
     final List<int> results = <int>[
-      for (List<SemanticsSortKey> tuple in tests) tuple[0].compareTo(tuple[1]),
+      for (final List<SemanticsSortKey> tuple in tests) tuple[0].compareTo(tuple[1]),
     ];
     expect(results, orderedEquals(expectedResults));
   });
diff --git a/packages/flutter/test/services/font_loader_test.dart b/packages/flutter/test/services/font_loader_test.dart
index c0242e7e172..029d7e76b5b 100644
--- a/packages/flutter/test/services/font_loader_test.dart
+++ b/packages/flutter/test/services/font_loader_test.dart
@@ -29,7 +29,7 @@ void main() {
       Uint8List.fromList(<int>[200]),
     ];
 
-    for (Uint8List asset in expectedAssets) {
+    for (final Uint8List asset in expectedAssets) {
       tfl.addFont(Future<ByteData>.value(ByteData.view(asset.buffer)));
     }
     await tfl.load();
diff --git a/packages/flutter/test/services/raw_keyboard_test.dart b/packages/flutter/test/services/raw_keyboard_test.dart
index 6c9dce864af..066ace86869 100644
--- a/packages/flutter/test/services/raw_keyboard_test.dart
+++ b/packages/flutter/test/services/raw_keyboard_test.dart
@@ -15,7 +15,7 @@ class _ModifierCheck {
 void main() {
   group('RawKeyboard', () {
     testWidgets('keysPressed is maintained', (WidgetTester tester) async {
-      for (String platform in <String>['linux', 'android', 'macos', 'fuchsia']) {
+      for (final String platform in <String>['linux', 'android', 'macos', 'fuchsia']) {
         RawKeyboard.instance.clearKeysPressed();
         expect(RawKeyboard.instance.keysPressed, isEmpty, reason: 'on $platform');
         await simulateKeyDownEvent(LogicalKeyboardKey.shiftLeft, platform: platform);
@@ -224,7 +224,7 @@ void main() {
     };
 
     test('modifier keys are recognized individually', () {
-      for (int modifier in modifierTests.keys) {
+      for (final int modifier in modifierTests.keys) {
         final RawKeyEvent event = RawKeyEvent.fromMessage(<String, dynamic>{
           'type': 'keydown',
           'keymap': 'android',
@@ -237,7 +237,7 @@ void main() {
           'deviceId': 1,
         });
         final RawKeyEventDataAndroid data = event.data as RawKeyEventDataAndroid;
-        for (ModifierKey key in ModifierKey.values) {
+        for (final ModifierKey key in ModifierKey.values) {
           if (modifierTests[modifier].key == key) {
             expect(
               data.isModifierPressed(key, side: modifierTests[modifier].side),
@@ -256,7 +256,7 @@ void main() {
       }
     });
     test('modifier keys are recognized when combined', () {
-      for (int modifier in modifierTests.keys) {
+      for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataAndroid.modifierFunction) {
           // No need to combine function key with itself.
           continue;
@@ -273,7 +273,7 @@ void main() {
           'deviceId': 1,
         });
         final RawKeyEventDataAndroid data = event.data as RawKeyEventDataAndroid;
-        for (ModifierKey key in ModifierKey.values) {
+        for (final ModifierKey key in ModifierKey.values) {
           if (modifierTests[modifier].key == key || key == ModifierKey.functionModifier) {
             expect(
               data.isModifierPressed(key, side: modifierTests[modifier].side),
@@ -454,7 +454,7 @@ void main() {
     };
 
     test('modifier keys are recognized individually', () {
-      for (int modifier in modifierTests.keys) {
+      for (final int modifier in modifierTests.keys) {
         final RawKeyEvent event = RawKeyEvent.fromMessage(<String, dynamic>{
           'type': 'keydown',
           'keymap': 'fuchsia',
@@ -463,7 +463,7 @@ void main() {
           'modifiers': modifier,
         });
         final RawKeyEventDataFuchsia data = event.data as RawKeyEventDataFuchsia;
-        for (ModifierKey key in ModifierKey.values) {
+        for (final ModifierKey key in ModifierKey.values) {
           if (modifierTests[modifier].key == key) {
             expect(
               data.isModifierPressed(key, side: modifierTests[modifier].side),
@@ -481,7 +481,7 @@ void main() {
       }
     });
     test('modifier keys are recognized when combined', () {
-      for (int modifier in modifierTests.keys) {
+      for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataFuchsia.modifierCapsLock) {
           // No need to combine caps lock key with itself.
           continue;
@@ -494,7 +494,7 @@ void main() {
           'modifiers': modifier | RawKeyEventDataFuchsia.modifierCapsLock,
         });
         final RawKeyEventDataFuchsia data = event.data as RawKeyEventDataFuchsia;
-        for (ModifierKey key in ModifierKey.values) {
+        for (final ModifierKey key in ModifierKey.values) {
           if (modifierTests[modifier].key == key || key == ModifierKey.capsLockModifier) {
             expect(
               data.isModifierPressed(key, side: modifierTests[modifier].side),
@@ -571,7 +571,7 @@ void main() {
     };
 
     test('modifier keys are recognized individually', () {
-      for (int modifier in modifierTests.keys) {
+      for (final int modifier in modifierTests.keys) {
         final RawKeyEvent event = RawKeyEvent.fromMessage(<String, dynamic>{
           'type': 'keydown',
           'keymap': 'macos',
@@ -581,7 +581,7 @@ void main() {
           'modifiers': modifier,
         });
         final RawKeyEventDataMacOs data = event.data as RawKeyEventDataMacOs;
-        for (ModifierKey key in ModifierKey.values) {
+        for (final ModifierKey key in ModifierKey.values) {
           if (modifierTests[modifier].key == key) {
             expect(
               data.isModifierPressed(key, side: modifierTests[modifier].side),
@@ -600,7 +600,7 @@ void main() {
       }
     });
     test('modifier keys are recognized when combined', () {
-      for (int modifier in modifierTests.keys) {
+      for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataMacOs.modifierCapsLock) {
           // No need to combine caps lock key with itself.
           continue;
@@ -615,7 +615,7 @@ void main() {
           'modifiers': modifier | RawKeyEventDataMacOs.modifierCapsLock,
         });
         final RawKeyEventDataMacOs data = event.data as RawKeyEventDataMacOs;
-        for (ModifierKey key in ModifierKey.values) {
+        for (final ModifierKey key in ModifierKey.values) {
           if (modifierTests[modifier].key == key || key == ModifierKey.capsLockModifier) {
             expect(
               data.isModifierPressed(key, side: modifierTests[modifier].side),
@@ -731,9 +731,9 @@ void main() {
     }
 
     test('modifier keys are recognized individually', () {
-      for (int modifier in modifierTests.keys) {
-        for (bool isDown in <bool>[true, false]) {
-          for (bool isLeft in <bool>[true, false]) {
+      for (final int modifier in modifierTests.keys) {
+        for (final bool isDown in <bool>[true, false]) {
+          for (final bool isLeft in <bool>[true, false]) {
             final RawKeyEvent event = RawKeyEvent.fromMessage(<String, dynamic>{
               'type': isDown ? 'keydown' : 'keyup',
               'keymap': 'linux',
@@ -745,7 +745,7 @@ void main() {
               'modifiers': isDown ? 0 : modifier,
             });
             final RawKeyEventDataLinux data = event.data as RawKeyEventDataLinux;
-            for (ModifierKey key in ModifierKey.values) {
+            for (final ModifierKey key in ModifierKey.values) {
               if (modifierTests[modifier].key == key) {
                 expect(
                   data.isModifierPressed(key, side: modifierTests[modifier].side),
@@ -766,7 +766,7 @@ void main() {
       }
     });
     test('modifier keys are recognized when combined', () {
-      for (int modifier in modifierTests.keys) {
+      for (final int modifier in modifierTests.keys) {
         if (modifier == GLFWKeyHelper.modifierControl) {
           // No need to combine CTRL key with itself.
           continue;
@@ -781,7 +781,7 @@ void main() {
           'modifiers': modifier | GLFWKeyHelper.modifierControl,
         });
         final RawKeyEventDataLinux data = event.data as RawKeyEventDataLinux;
-        for (ModifierKey key in ModifierKey.values) {
+        for (final ModifierKey key in ModifierKey.values) {
           if (modifierTests[modifier].key == key || key == ModifierKey.controlModifier) {
             expect(
               data.isModifierPressed(key, side: modifierTests[modifier].side),
@@ -894,7 +894,7 @@ void main() {
     };
 
     test('modifier keys are recognized individually', () {
-      for (int modifier in modifierTests.keys) {
+      for (final int modifier in modifierTests.keys) {
         final RawKeyEvent event = RawKeyEvent.fromMessage(<String, dynamic>{
           'type': 'keydown',
           'keymap': 'web',
@@ -903,7 +903,7 @@ void main() {
           'metaState': modifier,
         });
         final RawKeyEventDataWeb data = event.data as RawKeyEventDataWeb;
-        for (ModifierKey key in ModifierKey.values) {
+        for (final ModifierKey key in ModifierKey.values) {
           if (modifierTests[modifier] == key) {
             expect(
               data.isModifierPressed(key),
@@ -921,7 +921,7 @@ void main() {
       }
     });
     test('modifier keys are recognized when combined', () {
-      for (int modifier in modifierTests.keys) {
+      for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataWeb.modifierMeta) {
           // No need to combine meta key with itself.
           continue;
@@ -934,7 +934,7 @@ void main() {
           'metaState': modifier | RawKeyEventDataWeb.modifierMeta,
         });
         final RawKeyEventDataWeb data = event.data as RawKeyEventDataWeb;
-        for (ModifierKey key in ModifierKey.values) {
+        for (final ModifierKey key in ModifierKey.values) {
           if (modifierTests[modifier] == key || key == ModifierKey.metaModifier) {
             expect(
               data.isModifierPressed(key),
diff --git a/packages/flutter/test/widgets/animated_switcher_test.dart b/packages/flutter/test/widgets/animated_switcher_test.dart
index b6db226b469..38648528829 100644
--- a/packages/flutter/test/widgets/animated_switcher_test.dart
+++ b/packages/flutter/test/widgets/animated_switcher_test.dart
@@ -261,7 +261,7 @@ void main() {
     );
 
     expect(find.byType(Column), findsOneWidget);
-    for (Widget child in foundChildren) {
+    for (final Widget child in foundChildren) {
       expect(child, isInstanceOf<KeyedSubtree>());
     }
 
@@ -279,7 +279,7 @@ void main() {
     );
     await tester.pump(const Duration(milliseconds: 50));
 
-    for (Widget child in foundChildren) {
+    for (final Widget child in foundChildren) {
       expect(child, isInstanceOf<KeyedSubtree>());
       expect(
         find.descendant(of: find.byWidget(child), matching: find.byType(SizeTransition)),
@@ -429,7 +429,7 @@ void main() {
     await tester.pump(const Duration(milliseconds: 10));
 
     expect(foundChildren.length, equals(3));
-    for (Widget child in foundChildren) {
+    for (final Widget child in foundChildren) {
       expect(child, isInstanceOf<KeyedSubtree>());
       expect(
         find.descendant(of: find.byWidget(child), matching: find.byType(FadeTransition)),
@@ -459,7 +459,7 @@ void main() {
     await tester.pump(const Duration(milliseconds: 10));
 
     expect(foundChildren.length, equals(3));
-    for (Widget child in foundChildren) {
+    for (final Widget child in foundChildren) {
       expect(child, isInstanceOf<KeyedSubtree>());
       expect(
         find.descendant(of: find.byWidget(child), matching: find.byType(ScaleTransition)),
diff --git a/packages/flutter/test/widgets/build_scope_test.dart b/packages/flutter/test/widgets/build_scope_test.dart
index 5ab5d2c1992..f17d2926110 100644
--- a/packages/flutter/test/widgets/build_scope_test.dart
+++ b/packages/flutter/test/widgets/build_scope_test.dart
@@ -210,12 +210,12 @@ void main() {
     middle = part2;
     await tester.pumpWidget(part1);
 
-    for (StatefulWrapperState state in tester.stateList<StatefulWrapperState>(find.byType(StatefulWrapper))) {
+    for (final StatefulWrapperState state in tester.stateList<StatefulWrapperState>(find.byType(StatefulWrapper))) {
       expect(state.built, isNotNull);
       state.oldBuilt = state.built;
       state.trigger();
     }
-    for (StateSetter setState in setStates)
+    for (final StateSetter setState in setStates)
       setState(() { });
 
     StatefulWrapperState.buildId = 0;
@@ -223,7 +223,7 @@ void main() {
     didMiddle = false;
     await tester.pumpWidget(part2);
 
-    for (StatefulWrapperState state in tester.stateList<StatefulWrapperState>(find.byType(StatefulWrapper))) {
+    for (final StatefulWrapperState state in tester.stateList<StatefulWrapperState>(find.byType(StatefulWrapper))) {
       expect(state.built, isNotNull);
       expect(state.built, isNot(equals(state.oldBuilt)));
     }
diff --git a/packages/flutter/test/widgets/custom_painter_test.dart b/packages/flutter/test/widgets/custom_painter_test.dart
index 85e2dde4da9..abdd4adeaad 100644
--- a/packages/flutter/test/widgets/custom_painter_test.dart
+++ b/packages/flutter/test/widgets/custom_painter_test.dart
@@ -374,7 +374,7 @@ void _defineTests() {
     // Do the actions work?
     final SemanticsOwner semanticsOwner = tester.binding.pipelineOwner.semanticsOwner;
     int expectedLength = 1;
-    for (SemanticsAction action in allActions) {
+    for (final SemanticsAction action in allActions) {
       switch (action) {
         case SemanticsAction.moveCursorBackwardByCharacter:
         case SemanticsAction.moveCursorForwardByCharacter:
@@ -716,7 +716,7 @@ class _DiffTester {
           TestSemantics.rootChild(
             rect: TestSemantics.fullScreen,
             children: <TestSemantics>[
-              for (String label in labels)
+              for (final String label in labels)
                 TestSemantics(
                   rect: const Rect.fromLTRB(1.0, 1.0, 2.0, 2.0),
                   label: label,
@@ -783,7 +783,7 @@ class _SemanticsDiffTest extends CustomPainter {
 
   List<CustomPainterSemantics> buildSemantics(Size size) {
     final List<CustomPainterSemantics> semantics = <CustomPainterSemantics>[];
-    for (String label in data) {
+    for (final String label in data) {
       Key key;
       if (label.endsWith('-k')) {
         key = ValueKey<String>(label);
diff --git a/packages/flutter/test/widgets/draggable_scrollable_sheet_test.dart b/packages/flutter/test/widgets/draggable_scrollable_sheet_test.dart
index 16ec930e852..db35bf8a0ec 100644
--- a/packages/flutter/test/widgets/draggable_scrollable_sheet_test.dart
+++ b/packages/flutter/test/widgets/draggable_scrollable_sheet_test.dart
@@ -82,7 +82,7 @@ void main() {
     expect(tester.getRect(find.byKey(key)), const Rect.fromLTRB(0.0, 325.0, 800.0, 600.0));
   });
 
-  for (TargetPlatform platform in TargetPlatform.values) {
+  for (final TargetPlatform platform in TargetPlatform.values) {
     group('$platform Scroll Physics', () {
       debugDefaultTargetPlatformOverride = platform;
 
diff --git a/packages/flutter/test/widgets/editable_text_test.dart b/packages/flutter/test/widgets/editable_text_test.dart
index 638d47f3cc5..34af7e7d6dd 100644
--- a/packages/flutter/test/widgets/editable_text_test.dart
+++ b/packages/flutter/test/widgets/editable_text_test.dart
@@ -3180,7 +3180,7 @@ void main() {
           platform == 'macos' ? LogicalKeyboardKey.metaLeft : LogicalKeyboardKey.altLeft,
           platform: platform);
     }
-    for (LogicalKeyboardKey key in keys) {
+    for (final LogicalKeyboardKey key in keys) {
       await tester.sendKeyEvent(key, platform: platform);
       await tester.pump();
     }
@@ -4039,7 +4039,7 @@ void main() {
     final List<String> logOrder = <String>['TextInput.setClient', 'TextInput.show', 'TextInput.setEditableSizeAndTransform', 'TextInput.setStyle', 'TextInput.setEditingState', 'TextInput.setEditingState', 'TextInput.show'];
     expect(tester.testTextInput.log.length, 7);
     int index = 0;
-    for (MethodCall m in tester.testTextInput.log) {
+    for (final MethodCall m in tester.testTextInput.log) {
       expect(m.method, logOrder[index]);
       index++;
     }
@@ -4083,7 +4083,7 @@ void main() {
     ];
     expect(tester.testTextInput.log.length, logOrder.length);
     int index = 0;
-    for (MethodCall m in tester.testTextInput.log) {
+    for (final MethodCall m in tester.testTextInput.log) {
       expect(m.method, logOrder[index]);
       index++;
     }
@@ -4131,7 +4131,7 @@ void main() {
     ];
     expect(tester.testTextInput.log.length, logOrder.length);
     int index = 0;
-    for (MethodCall m in tester.testTextInput.log) {
+    for (final MethodCall m in tester.testTextInput.log) {
       expect(m.method, logOrder[index]);
       index++;
     }
diff --git a/packages/flutter/test/widgets/fade_in_image_test.dart b/packages/flutter/test/widgets/fade_in_image_test.dart
index b2f06788321..5b3b100ea57 100644
--- a/packages/flutter/test/widgets/fade_in_image_test.dart
+++ b/packages/flutter/test/widgets/fade_in_image_test.dart
@@ -78,7 +78,7 @@ FadeInImageParts findFadeInImage(WidgetTester tester) {
   final List<FadeInImageElements> elements = <FadeInImageElements>[];
   final Iterable<Element> rawImageElements = tester.elementList(find.byType(RawImage));
   ComponentElement fadeInImageElement;
-  for (Element rawImageElement in rawImageElements) {
+  for (final Element rawImageElement in rawImageElements) {
     Element fadeTransitionElement;
     rawImageElement.visitAncestorElements((Element ancestor) {
       if (ancestor.widget is FadeTransition) {
diff --git a/packages/flutter/test/widgets/fitted_box_test.dart b/packages/flutter/test/widgets/fitted_box_test.dart
index 721d28cf759..0469a5aa7b8 100644
--- a/packages/flutter/test/widgets/fitted_box_test.dart
+++ b/packages/flutter/test/widgets/fitted_box_test.dart
@@ -407,10 +407,10 @@ void main() {
 
   testWidgets('FittedBox layers - none - clip', (WidgetTester tester) async {
     final List<double> values = <double>[10.0, 50.0, 100.0];
-    for (double a in values) {
-      for (double b in values) {
-        for (double c in values) {
-          for (double d in values) {
+    for (final double a in values) {
+      for (final double b in values) {
+        for (final double c in values) {
+          for (final double d in values) {
             await tester.pumpWidget(
               Center(
                 child: SizedBox(
diff --git a/packages/flutter/test/widgets/grid_view_layout_test.dart b/packages/flutter/test/widgets/grid_view_layout_test.dart
index f3d22433a4d..5486a9fbd0b 100644
--- a/packages/flutter/test/widgets/grid_view_layout_test.dart
+++ b/packages/flutter/test/widgets/grid_view_layout_test.dart
@@ -32,7 +32,7 @@ void main() {
 
     expect(tester.renderObjectList<RenderBox>(find.byType(DecoratedBox)), hasLength(4));
 
-    for (RenderBox box in tester.renderObjectList<RenderBox>(find.byType(DecoratedBox))) {
+    for (final RenderBox box in tester.renderObjectList<RenderBox>(find.byType(DecoratedBox))) {
       expect(box.size.width, equals(100.0), reason: 'child width');
       expect(box.size.height, equals(100.0), reason: 'child height');
     }
@@ -59,7 +59,7 @@ void main() {
       ),
     );
 
-    for (RenderBox box in tester.renderObjectList<RenderBox>(find.byType(DecoratedBox))) {
+    for (final RenderBox box in tester.renderObjectList<RenderBox>(find.byType(DecoratedBox))) {
       expect(box.size.width, equals(50.0), reason: 'child width');
       expect(box.size.height, equals(50.0), reason: 'child height');
     }
diff --git a/packages/flutter/test/widgets/image_test.dart b/packages/flutter/test/widgets/image_test.dart
index 4a7a9538e81..db2d5e74565 100644
--- a/packages/flutter/test/widgets/image_test.dart
+++ b/packages/flutter/test/widgets/image_test.dart
@@ -1240,7 +1240,7 @@ class TestImageStreamCompleter extends ImageStreamCompleter {
       _currentImage = imageInfo;
     }
     final List<ImageStreamListener> localListeners = listeners.toList();
-    for (ImageStreamListener listener in localListeners) {
+    for (final ImageStreamListener listener in localListeners) {
       if (imageInfo != null) {
         listener.onImage(imageInfo, false);
       }
diff --git a/packages/flutter/test/widgets/linked_scroll_view_test.dart b/packages/flutter/test/widgets/linked_scroll_view_test.dart
index 7517cbf0039..e8f41291aa1 100644
--- a/packages/flutter/test/widgets/linked_scroll_view_test.dart
+++ b/packages/flutter/test/widgets/linked_scroll_view_test.dart
@@ -84,7 +84,7 @@ class LinkedScrollController extends ScrollController {
 
   Iterable<LinkedScrollActivity> link(LinkedScrollPosition driver) sync* {
     assert(hasClients);
-    for (LinkedScrollPosition position in positions.cast<LinkedScrollPosition>())
+    for (final LinkedScrollPosition position in positions.cast<LinkedScrollPosition>())
       yield position.link(driver);
   }
 
@@ -129,12 +129,12 @@ class LinkedScrollPosition extends ScrollPositionWithSingleContext {
     if (newActivity == null)
       return;
     if (_beforeActivities != null) {
-      for (LinkedScrollActivity activity in _beforeActivities)
+      for (final LinkedScrollActivity activity in _beforeActivities)
         activity.unlink(this);
       _beforeActivities.clear();
     }
     if (_afterActivities != null) {
-      for (LinkedScrollActivity activity in _afterActivities)
+      for (final LinkedScrollActivity activity in _afterActivities)
         activity.unlink(this);
       _afterActivities.clear();
     }
@@ -154,7 +154,7 @@ class LinkedScrollPosition extends ScrollPositionWithSingleContext {
       final double delta = value - minScrollExtent;
       _beforeActivities ??= HashSet<LinkedScrollActivity>();
       _beforeActivities.addAll(owner.linkWithBefore(this));
-      for (LinkedScrollActivity activity in _beforeActivities)
+      for (final LinkedScrollActivity activity in _beforeActivities)
         beforeOverscroll = math.min(activity.moveBy(delta), beforeOverscroll);
       assert(beforeOverscroll <= 0.0);
     }
@@ -164,7 +164,7 @@ class LinkedScrollPosition extends ScrollPositionWithSingleContext {
       final double delta = value - maxScrollExtent;
       _afterActivities ??= HashSet<LinkedScrollActivity>();
       _afterActivities.addAll(owner.linkWithAfter(this));
-      for (LinkedScrollActivity activity in _afterActivities)
+      for (final LinkedScrollActivity activity in _afterActivities)
         afterOverscroll = math.max(activity.moveBy(delta), afterOverscroll);
       assert(afterOverscroll >= 0.0);
     }
@@ -239,7 +239,7 @@ class LinkedScrollActivity extends ScrollActivity {
   double moveBy(double delta) {
     assert(drivers.isNotEmpty);
     ScrollDirection commonDirection;
-    for (LinkedScrollPosition driver in drivers) {
+    for (final LinkedScrollPosition driver in drivers) {
       commonDirection ??= driver.userScrollDirection;
       if (driver.userScrollDirection != commonDirection)
         commonDirection = ScrollDirection.idle;
@@ -250,7 +250,7 @@ class LinkedScrollActivity extends ScrollActivity {
 
   @override
   void dispose() {
-    for (LinkedScrollPosition driver in drivers)
+    for (final LinkedScrollPosition driver in drivers)
       driver.unlink(this);
     super.dispose();
   }
diff --git a/packages/flutter/test/widgets/list_view_builder_test.dart b/packages/flutter/test/widgets/list_view_builder_test.dart
index c90aa74f264..8dae1238be8 100644
--- a/packages/flutter/test/widgets/list_view_builder_test.dart
+++ b/packages/flutter/test/widgets/list_view_builder_test.dart
@@ -299,7 +299,7 @@ void main() {
 
     // ListView's height is 600, so items i0-i5 and s0-s4 fit.
     await tester.pumpWidget(buildFrame(itemCount: 25));
-    for (String s in <String>['i0', 's0', 'i1', 's1', 'i2', 's2', 'i3', 's3', 'i4', 's4', 'i5'])
+    for (final String s in <String>['i0', 's0', 'i1', 's1', 'i2', 's2', 'i3', 's3', 'i4', 's4', 'i5'])
       expect(find.text(s), findsOneWidget);
     expect(find.text('s5'), findsNothing);
     expect(find.text('i6'), findsNothing);
@@ -307,10 +307,10 @@ void main() {
 }
 
 void check({ List<int> visible = const <int>[], List<int> hidden = const <int>[] }) {
-  for (int i in visible) {
+  for (final int i in visible) {
     expect(find.text('$i'), findsOneWidget);
   }
-  for (int i in hidden) {
+  for (final int i in hidden) {
     expect(find.text('$i'), findsNothing);
   }
 }
diff --git a/packages/flutter/test/widgets/multichild_test.dart b/packages/flutter/test/widgets/multichild_test.dart
index 0b0e9cd3583..fe6242a6681 100644
--- a/packages/flutter/test/widgets/multichild_test.dart
+++ b/packages/flutter/test/widgets/multichild_test.dart
@@ -17,7 +17,7 @@ void checkTree(WidgetTester tester, List<BoxDecoration> expectedDecorations) {
   final RenderStack renderObject = element.renderObject as RenderStack;
   try {
     RenderObject child = renderObject.firstChild;
-    for (BoxDecoration decoration in expectedDecorations) {
+    for (final BoxDecoration decoration in expectedDecorations) {
       expect(child is RenderDecoratedBox, isTrue);
       final RenderDecoratedBox decoratedBox = child as RenderDecoratedBox;
       expect(decoratedBox.decoration, equals(decoration));
diff --git a/packages/flutter/test/widgets/page_view_test.dart b/packages/flutter/test/widgets/page_view_test.dart
index 405ee458c44..f48c62c2c38 100644
--- a/packages/flutter/test/widgets/page_view_test.dart
+++ b/packages/flutter/test/widgets/page_view_test.dart
@@ -663,7 +663,7 @@ void main() {
       await tester.pumpWidget(build());
 
       // The first 3 items should be visible and tappable.
-      for (int index in visiblePages) {
+      for (final int index in visiblePages) {
         expect(find.text(index.toString()), findsOneWidget);
         // The center of page 2's x-coordinate is 800, so we have to manually
         // offset it a bit to make sure the tap lands within the screen.
@@ -676,7 +676,7 @@ void main() {
       await tester.pump();
       // The last 3 items should be visible and tappable.
       visiblePages = const <int> [17, 18, 19];
-      for (int index in visiblePages) {
+      for (final int index in visiblePages) {
         expect(find.text('$index'), findsOneWidget);
         await tester.tap(find.text('$index'));
         expect(tappedIndex, index);
diff --git a/packages/flutter/test/widgets/parent_data_test.dart b/packages/flutter/test/widgets/parent_data_test.dart
index f53377257c2..4b450a44d3d 100644
--- a/packages/flutter/test/widgets/parent_data_test.dart
+++ b/packages/flutter/test/widgets/parent_data_test.dart
@@ -26,7 +26,7 @@ void checkTree(WidgetTester tester, List<TestParentData> expectedParentData) {
   final RenderStack renderObject = element.renderObject as RenderStack;
   try {
     RenderObject child = renderObject.firstChild;
-    for (TestParentData expected in expectedParentData) {
+    for (final TestParentData expected in expectedParentData) {
       expect(child is RenderDecoratedBox, isTrue);
       final RenderDecoratedBox decoratedBox = child as RenderDecoratedBox;
       expect(decoratedBox.parentData is StackParentData, isTrue);
diff --git a/packages/flutter/test/widgets/routes_test.dart b/packages/flutter/test/widgets/routes_test.dart
index 02b8d9cc636..32bde1e1a17 100644
--- a/packages/flutter/test/widgets/routes_test.dart
+++ b/packages/flutter/test/widgets/routes_test.dart
@@ -82,7 +82,7 @@ class TestRoute extends Route<String> with LocalHistoryRoute<String> {
   @override
   void dispose() {
     log('dispose');
-    for (OverlayEntry entry in _entries)
+    for (final OverlayEntry entry in _entries)
       entry.remove();
     _entries.clear();
     routes.remove(this);
diff --git a/packages/flutter/test/widgets/scrollbar_test.dart b/packages/flutter/test/widgets/scrollbar_test.dart
index f0809b78017..0ad1a7eb6e0 100644
--- a/packages/flutter/test/widgets/scrollbar_test.dart
+++ b/packages/flutter/test/widgets/scrollbar_test.dart
@@ -123,7 +123,7 @@ void main() {
       ];
 
       double lastCoefficient;
-      for (ScrollMetrics metrics in metricsList) {
+      for (final ScrollMetrics metrics in metricsList) {
         painter.update(metrics, metrics.axisDirection);
         painter.paint(testCanvas, size);
 
@@ -154,7 +154,7 @@ void main() {
       const double minLen = 0;
 
       const List<double> margins = <double> [-10, 1, viewportDimension/2 - 0.01];
-      for(double margin in margins) {
+      for (final double margin in margins) {
         painter = _buildPainter(
           mainAxisMargin: margin,
           minLength: minLen,
@@ -194,14 +194,14 @@ void main() {
       const Size size = Size(600, viewportDimension);
       const double margin = 4;
 
-      for(TextDirection textDirection in TextDirection.values) {
+      for (final TextDirection textDirection in TextDirection.values) {
         painter = _buildPainter(
           crossAxisMargin: margin,
           scrollMetrics: startingMetrics,
           textDirection: textDirection,
         );
 
-        for(AxisDirection direction in AxisDirection.values) {
+        for (final AxisDirection direction in AxisDirection.values) {
           painter.update(
             startingMetrics.copyWith(axisDirection: direction),
             direction,
@@ -454,7 +454,7 @@ void main() {
         viewportDimension: size.height,
       );
 
-      for(double minLength in <double> [_kMinThumbExtent, double.infinity]) {
+      for (final double minLength in <double>[_kMinThumbExtent, double.infinity]) {
         // Disregard `minLength` and `minOverscrollLength` to keep
         // scroll direction correct, if needed
         painter = _buildPainter(
@@ -471,7 +471,7 @@ void main() {
 
         Rect previousRect;
 
-        for(ScrollMetrics metrics in metricsList) {
+        for (final ScrollMetrics metrics in metricsList) {
           painter.update(metrics, metrics.axisDirection);
           painter.paint(testCanvas, size);
           final Rect rect = captureRect();
diff --git a/packages/flutter/test/widgets/semantics_test.dart b/packages/flutter/test/widgets/semantics_test.dart
index 8073c7bc65e..2803695d0d2 100644
--- a/packages/flutter/test/widgets/semantics_test.dart
+++ b/packages/flutter/test/widgets/semantics_test.dart
@@ -436,7 +436,7 @@ void main() {
     // Do the actions work?
     final SemanticsOwner semanticsOwner = tester.binding.pipelineOwner.semanticsOwner;
     int expectedLength = 1;
-    for (SemanticsAction action in allActions) {
+    for (final SemanticsAction action in allActions) {
       switch (action) {
         case SemanticsAction.moveCursorBackwardByCharacter:
         case SemanticsAction.moveCursorForwardByCharacter:
diff --git a/packages/flutter/test/widgets/semantics_tester.dart b/packages/flutter/test/widgets/semantics_tester.dart
index 3a518db405e..dc3d2e71ee4 100644
--- a/packages/flutter/test/widgets/semantics_tester.dart
+++ b/packages/flutter/test/widgets/semantics_tester.dart
@@ -380,7 +380,7 @@ class TestSemantics {
     if (thickness != null)
       buf.writeln('$indent  thickness: $thickness,');
     buf.writeln('$indent  children: <TestSemantics>[');
-    for (TestSemantics child in children) {
+    for (final TestSemantics child in children) {
       buf.writeln('${child.toString(indentAmount + 2)},');
     }
     buf.writeln('$indent  ],');
diff --git a/packages/flutter/test/widgets/semantics_tester_generateTestSemanticsExpressionForCurrentSemanticsTree_test.dart b/packages/flutter/test/widgets/semantics_tester_generateTestSemanticsExpressionForCurrentSemanticsTree_test.dart
index f5f599a6399..b94bb2d5cd4 100644
--- a/packages/flutter/test/widgets/semantics_tester_generateTestSemanticsExpressionForCurrentSemanticsTree_test.dart
+++ b/packages/flutter/test/widgets/semantics_tester_generateTestSemanticsExpressionForCurrentSemanticsTree_test.dart
@@ -62,7 +62,7 @@ void _tests() {
       .trim() + ',';
 
     File findThisTestFile(Directory directory) {
-      for (FileSystemEntity entity in directory.listSync()) {
+      for (final FileSystemEntity entity in directory.listSync()) {
         if (entity is Directory) {
           final File childSearch = findThisTestFile(entity);
           if (childSearch != null) {
diff --git a/packages/flutter/test/widgets/semantics_traversal_test.dart b/packages/flutter/test/widgets/semantics_traversal_test.dart
index 9e4578bee9e..b7ee4d06d7d 100644
--- a/packages/flutter/test/widgets/semantics_traversal_test.dart
+++ b/packages/flutter/test/widgets/semantics_traversal_test.dart
@@ -66,7 +66,7 @@ void main() {
   // │ B │
   // └───┘
   testTraversal('Semantics traverses vertically top-to-bottom', (TraversalTester tester) async {
-    for (TextDirection textDirection in TextDirection.values) {
+    for (final TextDirection textDirection in TextDirection.values) {
       await tester.test(
         textDirection: textDirection,
         children: <String, Rect>{
diff --git a/packages/flutter/test/widgets/shadow_test.dart b/packages/flutter/test/widgets/shadow_test.dart
index f95f7537ac0..95a1ca97ecc 100644
--- a/packages/flutter/test/widgets/shadow_test.dart
+++ b/packages/flutter/test/widgets/shadow_test.dart
@@ -56,7 +56,7 @@ void main() {
         ),
       );
     }
-    for (int elevation in kElevationToShadow.keys) {
+    for (final int elevation in kElevationToShadow.keys) {
       await tester.pumpWidget(build(elevation));
       await expectLater(
         find.byType(Container),
@@ -120,7 +120,7 @@ void main() {
         ),
       );
     }
-    for (int elevation in kElevationToShadow.keys) {
+    for (final int elevation in kElevationToShadow.keys) {
       await tester.pumpWidget(build(elevation.toDouble()));
       await expectLater(
         find.byType(Container),
diff --git a/packages/flutter/test/widgets/widget_inspector_test.dart b/packages/flutter/test/widgets/widget_inspector_test.dart
index 638757ddcbd..70c18dcc436 100644
--- a/packages/flutter/test/widgets/widget_inspector_test.dart
+++ b/packages/flutter/test/widgets/widget_inspector_test.dart
@@ -1260,7 +1260,7 @@ class TestWidgetInspectorService extends Object with WidgetInspectorService {
         final List<Object> propertiesJson = childJson['properties'] as List<Object>;
         final DiagnosticsNode diagnosticsNode = service.toObject(childJson['objectId'] as String) as DiagnosticsNode;
         final List<DiagnosticsNode> expectedProperties = diagnosticsNode.getProperties();
-        for (Map<String, Object> propertyJson in propertiesJson.cast<Map<String, Object>>()) {
+        for (final Map<String, Object> propertyJson in propertiesJson.cast<Map<String, Object>>()) {
           final Object property = service.toObject(propertyJson['objectId'] as String);
           expect(property, isInstanceOf<DiagnosticsNode>());
           expect(expectedProperties, contains(property));
@@ -1296,12 +1296,12 @@ class TestWidgetInspectorService extends Object with WidgetInspectorService {
         expect(service.toObject(childJson['valueId'] as String), equals(children[i].value));
         expect(service.toObject(childJson['objectId'] as String), isInstanceOf<DiagnosticsNode>());
         final List<Object> propertiesJson = childJson['properties'] as List<Object>;
-        for (Map<String, Object> propertyJson in propertiesJson.cast<Map<String, Object>>()) {
+        for (final Map<String, Object> propertyJson in propertiesJson.cast<Map<String, Object>>()) {
           expect(propertyJson, isNot(contains('children')));
         }
         final DiagnosticsNode diagnosticsNode = service.toObject(childJson['objectId'] as String) as DiagnosticsNode;
         final List<DiagnosticsNode> expectedProperties = diagnosticsNode.getProperties();
-        for (Map<String, Object> propertyJson in propertiesJson.cast<Map<String, Object>>()) {
+        for (final Map<String, Object> propertyJson in propertiesJson.cast<Map<String, Object>>()) {
           final Object property = service.toObject(propertyJson['objectId'] as String);
           expect(property, isInstanceOf<DiagnosticsNode>());
           expect(expectedProperties, contains(property));
@@ -1313,9 +1313,9 @@ class TestWidgetInspectorService extends Object with WidgetInspectorService {
         <String, String>{'arg': id, 'objectGroup': group, 'subtreeDepth': '3'},
       ) as Map<String, Object>;
       final List<Object> deepChildrenJson = deepSubtreeJson['children'] as List<Object>;
-      for(Map<String, Object> childJson in deepChildrenJson.cast<Map<String, Object>>()) {
+      for (final Map<String, Object> childJson in deepChildrenJson.cast<Map<String, Object>>()) {
         final List<Object> propertiesJson = childJson['properties'] as List<Object>;
-        for (Map<String, Object> propertyJson in propertiesJson.cast<Map<String, Object>>()) {
+        for (final Map<String, Object> propertyJson in propertiesJson.cast<Map<String, Object>>()) {
           expect(propertyJson, contains('children'));
         }
       }
@@ -2584,7 +2584,7 @@ class TestWidgetInspectorService extends Object with WidgetInspectorService {
 
       final List<Map<String, Object>> appBars = <Map<String, Object>>[];
       void visitChildren(List<dynamic> children) {
-        for (Map<String, Object> child in children.cast<Map<String, Object>>()) {
+        for (final Map<String, Object> child in children.cast<Map<String, Object>>()) {
           if (child['description'] == 'AppBar') {
             appBars.add(child);
           }
diff --git a/packages/flutter_driver/lib/src/common/wait.dart b/packages/flutter_driver/lib/src/common/wait.dart
index d5ba23d4704..b8f5f0e0067 100644
--- a/packages/flutter_driver/lib/src/common/wait.dart
+++ b/packages/flutter_driver/lib/src/common/wait.dart
@@ -251,7 +251,7 @@ class CombinedCondition extends SerializableWaitCondition {
     }
 
     final List<SerializableWaitCondition> conditions = <SerializableWaitCondition>[];
-    for (Map<String, dynamic> condition in json.decode(jsonMap['conditions'])) {
+    for (final Map<String, dynamic> condition in json.decode(jsonMap['conditions'])) {
       conditions.add(_deserialize(condition.cast<String, String>()));
     }
     return CombinedCondition(conditions);
diff --git a/packages/flutter_driver/lib/src/driver/vmservice_driver.dart b/packages/flutter_driver/lib/src/driver/vmservice_driver.dart
index 8db6af8a95b..2a421a076d2 100644
--- a/packages/flutter_driver/lib/src/driver/vmservice_driver.dart
+++ b/packages/flutter_driver/lib/src/driver/vmservice_driver.dart
@@ -416,7 +416,7 @@ class VMServiceFlutterDriver extends FlutterDriver {
 
   Future<bool> _isPrecompiledMode() async {
     final List<Map<String, dynamic>> flags = await getVmFlags();
-    for(Map<String, dynamic> flag in flags) {
+    for(final Map<String, dynamic> flag in flags) {
       if (flag['name'] == 'precompiled_mode') {
         return flag['valueAsString'] == 'true';
       }
diff --git a/packages/flutter_driver/lib/src/driver/web_driver.dart b/packages/flutter_driver/lib/src/driver/web_driver.dart
index 9059ecf6d1f..ba772a38674 100644
--- a/packages/flutter_driver/lib/src/driver/web_driver.dart
+++ b/packages/flutter_driver/lib/src/driver/web_driver.dart
@@ -123,7 +123,7 @@ class WebFlutterDriver extends FlutterDriver {
     _checkBrowserSupportsTimeline();
 
     final List<Map<String, dynamic>> events = <Map<String, dynamic>>[];
-    for (sync_io.LogEntry entry in _connection.logs) {
+    for (final sync_io.LogEntry entry in _connection.logs) {
       if (_startTime.isBefore(entry.timestamp)) {
         final Map<String, dynamic> data = jsonDecode(entry.message)['message'] as Map<String, dynamic>;
         if (data['method'] == 'Tracing.dataCollected') {
diff --git a/packages/flutter_driver/lib/src/extension/wait_conditions.dart b/packages/flutter_driver/lib/src/extension/wait_conditions.dart
index 336d48ceda8..fa7dac00329 100644
--- a/packages/flutter_driver/lib/src/extension/wait_conditions.dart
+++ b/packages/flutter_driver/lib/src/extension/wait_conditions.dart
@@ -185,7 +185,7 @@ class _InternalCombinedCondition implements WaitCondition {
   @override
   Future<void> wait() async {
     while (!condition) {
-      for (WaitCondition condition in conditions) {
+      for (final WaitCondition condition in conditions) {
         assert (condition != null);
         await condition.wait();
       }
diff --git a/packages/flutter_driver/test/src/real_tests/timeline_summary_test.dart b/packages/flutter_driver/test/src/real_tests/timeline_summary_test.dart
index 77c4950641c..6e2c00f5275 100644
--- a/packages/flutter_driver/test/src/real_tests/timeline_summary_test.dart
+++ b/packages/flutter_driver/test/src/real_tests/timeline_summary_test.dart
@@ -47,7 +47,7 @@ void main() {
     List<Map<String, dynamic>> rasterizeTimeSequenceInMillis(List<int> sequence) {
       final List<Map<String, dynamic>> result = <Map<String, dynamic>>[];
       int t = 0;
-      for (int duration in sequence) {
+      for (final int duration in sequence) {
         result.add(begin(t));
         t += duration * 1000;
         result.add(end(t));
diff --git a/packages/flutter_goldens/lib/flutter_goldens.dart b/packages/flutter_goldens/lib/flutter_goldens.dart
index 574ed7d2442..6ffe4a743b7 100644
--- a/packages/flutter_goldens/lib/flutter_goldens.dart
+++ b/packages/flutter_goldens/lib/flutter_goldens.dart
@@ -506,7 +506,7 @@ class FlutterLocalFileComparator extends FlutterGoldenFileComparator with LocalC
 
     ComparisonResult result;
     final Map<String, ComparisonResult> failureDiffs = <String, ComparisonResult>{};
-    for (String expectation in testExpectations) {
+    for (final String expectation in testExpectations) {
       final List<int> goldenBytes = await skiaClient.getImageBytes(expectation);
 
       result = GoldenFileComparator.compareLists(
@@ -520,7 +520,7 @@ class FlutterLocalFileComparator extends FlutterGoldenFileComparator with LocalC
       failureDiffs[expectation] = result;
     }
 
-    for (MapEntry<String, ComparisonResult> entry in failureDiffs.entries) {
+    for (final MapEntry<String, ComparisonResult> entry in failureDiffs.entries) {
       if (await skiaClient.isValidDigestForExpectation(entry.key, golden.path))
         generateFailureOutput(entry.value, golden, basedir, key: entry.key);
     }
diff --git a/packages/flutter_localizations/test/cupertino/translations_test.dart b/packages/flutter_localizations/test/cupertino/translations_test.dart
index 81c18274c55..d13974eb2cf 100644
--- a/packages/flutter_localizations/test/cupertino/translations_test.dart
+++ b/packages/flutter_localizations/test/cupertino/translations_test.dart
@@ -7,7 +7,7 @@ import 'package:flutter_localizations/flutter_localizations.dart';
 import 'package:flutter_test/flutter_test.dart';
 
 void main() {
-  for (String language in kCupertinoSupportedLanguages) {
+  for (final String language in kCupertinoSupportedLanguages) {
     testWidgets('translations exist for $language', (WidgetTester tester) async {
       final Locale locale = Locale(language);
 
diff --git a/packages/flutter_localizations/test/material/date_picker_test.dart b/packages/flutter_localizations/test/material/date_picker_test.dart
index 99d8074d395..3563f174555 100644
--- a/packages/flutter_localizations/test/material/date_picker_test.dart
+++ b/packages/flutter_localizations/test/material/date_picker_test.dart
@@ -51,7 +51,7 @@ void main() {
       },
     };
 
-    for (Locale locale in testLocales.keys) {
+    for (final Locale locale in testLocales.keys) {
       testWidgets('shows dates for $locale', (WidgetTester tester) async {
         final List<String> expectedDaysOfWeek = testLocales[locale]['expectedDaysOfWeek'] as List<String>;
         final List<String> expectedDaysOfMonth = testLocales[locale]['expectedDaysOfMonth'] as List<String>;
@@ -70,12 +70,12 @@ void main() {
 
         expect(find.text(expectedMonthYearHeader), findsOneWidget);
 
-        for (String dayOfWeek in expectedDaysOfWeek) {
+        for (final String dayOfWeek in expectedDaysOfWeek) {
           expect(find.text(dayOfWeek), findsWidgets);
         }
 
         Offset previousCellOffset;
-        for (String dayOfMonth in expectedDaysOfMonth) {
+        for (final String dayOfMonth in expectedDaysOfMonth) {
           final Finder dayCell = find.descendant(of: find.byType(GridView), matching: find.text(dayOfMonth));
           expect(dayCell, findsOneWidget);
 
diff --git a/packages/flutter_localizations/test/material/time_picker_test.dart b/packages/flutter_localizations/test/material/time_picker_test.dart
index a4bbc7dcd82..597e2412f96 100644
--- a/packages/flutter_localizations/test/material/time_picker_test.dart
+++ b/packages/flutter_localizations/test/material/time_picker_test.dart
@@ -68,7 +68,7 @@ void main() {
       const Locale('zh', 'ZH'): const <String>['period', 'hour', 'string :', 'minute'], //'ah:mm'
     };
 
-    for (Locale locale in locales.keys) {
+    for (final Locale locale in locales.keys) {
       final Offset center = await startPicker(tester, (TimeOfDay time) { }, locale: locale);
       final List<String> actual = <String>[];
       tester.element(find.byType(CustomMultiChildLayout)).visitChildren((Element child) {
@@ -114,7 +114,7 @@ void main() {
       Locale('en', 'GB'), // HH
       Locale('es', 'ES'), // H
     ];
-    for (Locale locale in locales) {
+    for (final Locale locale in locales) {
       // Tap along the segment stretching from the center to the edge at
       // 12:00 AM position. There are two rings. At ~70% mark, the ring
       // switches between inner ring and outer ring.
diff --git a/packages/flutter_localizations/test/material/translations_test.dart b/packages/flutter_localizations/test/material/translations_test.dart
index 782131b6239..fa2c9468e99 100644
--- a/packages/flutter_localizations/test/material/translations_test.dart
+++ b/packages/flutter_localizations/test/material/translations_test.dart
@@ -7,7 +7,7 @@ import 'package:flutter_localizations/flutter_localizations.dart';
 import 'package:flutter_test/flutter_test.dart';
 
 void main() {
-  for (String language in kMaterialSupportedLanguages) {
+  for (final String language in kMaterialSupportedLanguages) {
     testWidgets('translations exist for $language', (WidgetTester tester) async {
       final Locale locale = Locale(language);
 
diff --git a/packages/flutter_test/lib/src/accessibility.dart b/packages/flutter_test/lib/src/accessibility.dart
index 12c617ca4ef..2af0d543f3b 100644
--- a/packages/flutter_test/lib/src/accessibility.dart
+++ b/packages/flutter_test/lib/src/accessibility.dart
@@ -215,7 +215,7 @@ class MinimumTextContrastGuideline extends AccessibilityGuideline {
         children.add(child);
         return true;
       });
-      for (SemanticsNode child in children) {
+      for (final SemanticsNode child in children) {
         result += await evaluateNode(child);
       }
       if (_shouldSkipNode(data)) {
@@ -348,7 +348,7 @@ class MinimumTextContrastGuideline extends AccessibilityGuideline {
 class _ContrastReport {
   factory _ContrastReport(List<int> colors) {
     final Map<int, int> colorHistogram = <int, int>{};
-    for (int color in colors) {
+    for (final int color in colors) {
       colorHistogram[color] = (colorHistogram[color] ?? 0) + 1;
     }
     if (colorHistogram.length == 1) {
@@ -358,7 +358,7 @@ class _ContrastReport {
     // to determine the lighter and darker color, partition the colors
     // by lightness and then choose the mode from each group.
     double averageLightness = 0.0;
-    for (int color in colorHistogram.keys) {
+    for (final int color in colorHistogram.keys) {
       final HSLColor hslColor = HSLColor.fromColor(Color(color));
       averageLightness += hslColor.lightness * colorHistogram[color];
     }
@@ -369,7 +369,7 @@ class _ContrastReport {
     int lightCount = 0;
     int darkCount = 0;
     // Find the most frequently occurring light and dark color.
-    for (MapEntry<int, int> entry in colorHistogram.entries) {
+    for (final MapEntry<int, int> entry in colorHistogram.entries) {
       final HSLColor color = HSLColor.fromColor(Color(entry.key));
       final int count = entry.value;
       if (color.lightness <= averageLightness && count > darkCount) {
diff --git a/packages/flutter_test/lib/src/binding.dart b/packages/flutter_test/lib/src/binding.dart
index 32c91c085ec..fbdfab562c2 100644
--- a/packages/flutter_test/lib/src/binding.dart
+++ b/packages/flutter_test/lib/src/binding.dart
@@ -1119,7 +1119,7 @@ class AutomatedTestWidgetsFlutterBinding extends TestWidgetsFlutterBinding {
       }
 
       debugPrint('Pending timers:');
-      for (String timerInfo in _currentFakeAsync.pendingTimersDebugInfo) {
+      for (final String timerInfo in _currentFakeAsync.pendingTimersDebugInfo) {
         final int firstLineEnd = timerInfo.indexOf('\n');
         assert(firstLineEnd != -1);
 
@@ -1657,7 +1657,7 @@ class _LiveTestRenderView extends RenderView {
         ..strokeWidth = radius / 10.0
         ..style = PaintingStyle.stroke;
       bool dirty = false;
-      for (int pointer in _pointers.keys) {
+      for (final int pointer in _pointers.keys) {
         final _LiveTestPointerRecord record = _pointers[pointer];
         paint.color = record.color.withOpacity(record.decay < 0 ? (record.decay / (_kPointerDecay - 1)) : 1.0);
         canvas.drawPath(path.shift(record.position), paint);
diff --git a/packages/flutter_test/lib/src/event_simulation.dart b/packages/flutter_test/lib/src/event_simulation.dart
index 63b62f41726..11cdaea68ec 100644
--- a/packages/flutter_test/lib/src/event_simulation.dart
+++ b/packages/flutter_test/lib/src/event_simulation.dart
@@ -57,7 +57,7 @@ class KeyEventSimulator {
         map = kLinuxToPhysicalKey;
         break;
     }
-    for (int code in map.keys) {
+    for (final int code in map.keys) {
       if (key.debugName == map[code].debugName) {
         scanCode = code;
         break;
@@ -84,7 +84,7 @@ class KeyEventSimulator {
         map = kGlfwToLogicalKey;
         break;
     }
-    for (int code in map.keys) {
+    for (final int code in map.keys) {
       if (key.debugName == map[code].debugName) {
         keyCode = code;
         break;
diff --git a/packages/flutter_test/lib/src/finders.dart b/packages/flutter_test/lib/src/finders.dart
index d6d8de60a57..a95c3af2e18 100644
--- a/packages/flutter_test/lib/src/finders.dart
+++ b/packages/flutter_test/lib/src/finders.dart
@@ -719,7 +719,7 @@ class _AncestorFinder extends Finder {
   @override
   Iterable<Element> get allCandidates {
     final List<Element> candidates = <Element>[];
-    for (Element root in descendant.evaluate()) {
+    for (final Element root in descendant.evaluate()) {
       final List<Element> ancestors = <Element>[];
       if (matchRoot)
         ancestors.add(root);
diff --git a/packages/flutter_test/lib/src/matchers.dart b/packages/flutter_test/lib/src/matchers.dart
index 866e3d08a06..529774ba835 100644
--- a/packages/flutter_test/lib/src/matchers.dart
+++ b/packages/flutter_test/lib/src/matchers.dart
@@ -1184,7 +1184,7 @@ class _IsMethodCall extends Matcher {
   bool _deepEqualsMap(Map<dynamic, dynamic> a, Map<dynamic, dynamic> b) {
     if (a.length != b.length)
       return false;
-    for (dynamic key in a.keys) {
+    for (final dynamic key in a.keys) {
       if (!b.containsKey(key) || !_deepEquals(a[key], b[key]))
         return false;
     }
@@ -1782,7 +1782,7 @@ class _MatchesSemanticsData extends Matcher {
       description.add(' with custom hints: $hintOverrides');
     if (children != null) {
       description.add(' with children:\n');
-      for (_MatchesSemanticsData child in children.cast<_MatchesSemanticsData>())
+      for (final _MatchesSemanticsData child in children.cast<_MatchesSemanticsData>())
         child.describe(description);
     }
     return description;
@@ -1824,11 +1824,11 @@ class _MatchesSemanticsData extends Matcher {
       return failWithDescription(matchState, 'maxValueLength was: ${data.maxValueLength}');
     if (actions != null) {
       int actionBits = 0;
-      for (SemanticsAction action in actions)
+      for (final SemanticsAction action in actions)
         actionBits |= action.index;
       if (actionBits != data.actions) {
         final List<String> actionSummary = <String>[
-          for (SemanticsAction action in SemanticsAction.values.values)
+          for (final SemanticsAction action in SemanticsAction.values.values)
             if ((data.actions & action.index) != 0)
               describeEnum(action),
         ];
@@ -1858,11 +1858,11 @@ class _MatchesSemanticsData extends Matcher {
     }
     if (flags != null) {
       int flagBits = 0;
-      for (SemanticsFlag flag in flags)
+      for (final SemanticsFlag flag in flags)
         flagBits |= flag.index;
       if (flagBits != data.flags) {
         final List<String> flagSummary = <String>[
-          for (SemanticsFlag flag in SemanticsFlag.values.values)
+          for (final SemanticsFlag flag in SemanticsFlag.values.values)
             if ((data.flags & flag.index) != 0)
               describeEnum(flag),
         ];
diff --git a/packages/flutter_test/lib/src/test_async_utils.dart b/packages/flutter_test/lib/src/test_async_utils.dart
index 9c507331474..9f8100e179b 100644
--- a/packages/flutter_test/lib/src/test_async_utils.dart
+++ b/packages/flutter_test/lib/src/test_async_utils.dart
@@ -274,7 +274,7 @@ class TestAsyncUtils {
         ErrorSummary('Asynchronous call to guarded function leaked.'),
         ErrorHint('You must use "await" with all Future-returning test APIs.')
       ];
-      for (_AsyncScope scope in _scopeStack) {
+      for (final _AsyncScope scope in _scopeStack) {
         final _StackEntry guarder = _findResponsibleMethod(scope.creationStack, 'guard', information);
         if (guarder != null) {
           information.add(ErrorDescription(
diff --git a/packages/flutter_test/lib/src/test_compat.dart b/packages/flutter_test/lib/src/test_compat.dart
index c4f5496a340..f157a370d70 100644
--- a/packages/flutter_test/lib/src/test_compat.dart
+++ b/packages/flutter_test/lib/src/test_compat.dart
@@ -54,7 +54,7 @@ Future<void> _runGroup(Suite suiteConfig, Group group, List<Group> parents, _Rep
       setUpAllSucceeded = liveTest.state.result.isPassing;
     }
     if (setUpAllSucceeded) {
-      for (GroupEntry entry in group.entries) {
+      for (final GroupEntry entry in group.entries) {
         if (entry is Group) {
           await _runGroup(suiteConfig, entry, parents, reporter);
         } else if (entry.metadata.skip) {
@@ -502,7 +502,7 @@ String _prefixLines(String text, String prefix, { String first, String last, Str
   }
   final StringBuffer buffer = StringBuffer('$first${lines.first}\n');
   // Write out all but the first and last lines with [prefix].
-  for (String line in lines.skip(1).take(lines.length - 2)) {
+  for (final String line in lines.skip(1).take(lines.length - 2)) {
     buffer.writeln('$prefix$line');
   }
   buffer.write('$last${lines.last}');
diff --git a/packages/flutter_test/lib/src/widget_tester.dart b/packages/flutter_test/lib/src/widget_tester.dart
index 49760cf2c89..afac83bdb83 100644
--- a/packages/flutter_test/lib/src/widget_tester.dart
+++ b/packages/flutter_test/lib/src/widget_tester.dart
@@ -117,7 +117,7 @@ void testWidgets(
   assert(variant.values.isNotEmpty, 'There must be at least on value to test in the testing variant');
   final TestWidgetsFlutterBinding binding = TestWidgetsFlutterBinding.ensureInitialized() as TestWidgetsFlutterBinding;
   final WidgetTester tester = WidgetTester._(binding);
-  for (dynamic value in variant.values) {
+  for (final dynamic value in variant.values) {
     final String variationDescription = variant.describeValue(value);
     final String combinedDescription = variationDescription.isNotEmpty ? '$description ($variationDescription)' : description;
     test(
@@ -629,7 +629,7 @@ class WidgetTester extends WidgetController implements HitTestDispatcher, Ticker
       int numberOfTypes = 0;
       int totalNumber = 0;
       debugPrint('Some possible finders for the widgets at ${binding.globalToLocal(event.position)}:');
-      for (Element element in candidates) {
+      for (final Element element in candidates) {
         if (totalNumber > 13) // an arbitrary number of finders that feels useful without being overwhelming
           break;
         totalNumber += 1; // optimistically assume we'll be able to describe it
@@ -755,7 +755,7 @@ class WidgetTester extends WidgetController implements HitTestDispatcher, Ticker
   void verifyTickersWereDisposed([ String when = 'when none should have been' ]) {
     assert(when != null);
     if (_tickers != null) {
-      for (Ticker ticker in _tickers) {
+      for (final Ticker ticker in _tickers) {
         if (ticker.isActive) {
           throw FlutterError.fromParts(<DiagnosticsNode>[
             ErrorSummary('A Ticker was active $when.'),
diff --git a/packages/flutter_test/test/event_simulation_test.dart b/packages/flutter_test/test/event_simulation_test.dart
index f4d74ad221c..91fefce391a 100644
--- a/packages/flutter_test/test/event_simulation_test.dart
+++ b/packages/flutter_test/test/event_simulation_test.dart
@@ -25,7 +25,7 @@ void main() {
     focusNode.requestFocus();
     await tester.idle();
 
-    for (String platform in platforms) {
+    for (final String platform in platforms) {
       await tester.sendKeyEvent(LogicalKeyboardKey.shiftLeft, platform: platform);
       await tester.sendKeyEvent(LogicalKeyboardKey.shift, platform: platform);
       await tester.sendKeyDownEvent(LogicalKeyboardKey.keyA, platform: platform);
diff --git a/packages/flutter_test/test/matchers_test.dart b/packages/flutter_test/test/matchers_test.dart
index ecd0f18b3e7..79af0619813 100644
--- a/packages/flutter_test/test/matchers_test.dart
+++ b/packages/flutter_test/test/matchers_test.dart
@@ -530,9 +530,9 @@ void main() {
       int actions = 0;
       int flags = 0;
       const CustomSemanticsAction action = CustomSemanticsAction(label: 'test');
-      for (int index in SemanticsAction.values.keys)
+      for (final int index in SemanticsAction.values.keys)
         actions |= index;
-      for (int index in SemanticsFlag.values.keys)
+      for (final int index in SemanticsFlag.values.keys)
         // TODO(mdebbar): Remove this if after https://github.com/flutter/engine/pull/9894
         if (SemanticsFlag.values[index] != SemanticsFlag.isMultiline)
           flags |= index;
diff --git a/packages/flutter_test/test/test_config/config_test_utils.dart b/packages/flutter_test/test/test_config/config_test_utils.dart
index 31d2c3e2c74..a7397a81166 100644
--- a/packages/flutter_test/test/test_config/config_test_utils.dart
+++ b/packages/flutter_test/test/test_config/config_test_utils.dart
@@ -20,7 +20,7 @@ void testConfig(
 
   test(description, () {
     expect(actualStringValue, expectedStringValue);
-    for (Type key in otherExpectedValues.keys) {
+    for (final Type key in otherExpectedValues.keys) {
       expect(otherActualValues[key], otherExpectedValues[key]);
     }
   });
diff --git a/packages/flutter_tools/bin/fuchsia_asset_builder.dart b/packages/flutter_tools/bin/fuchsia_asset_builder.dart
index 5e980aa3339..dd75c654bbc 100644
--- a/packages/flutter_tools/bin/fuchsia_asset_builder.dart
+++ b/packages/flutter_tools/bin/fuchsia_asset_builder.dart
@@ -86,7 +86,7 @@ Future<void> writeFuchsiaManifest(AssetBundle assets, String outputBase, String
   await destFile.create(recursive: true);
   final libfs.IOSink outFile = destFile.openWrite();
 
-  for (String path in assets.entries.keys) {
+  for (final String path in assets.entries.keys) {
     outFile.write('data/$componentName/$path=$outputBase/$path\n');
   }
   await outFile.flush();
diff --git a/packages/flutter_tools/bin/fuchsia_tester.dart b/packages/flutter_tools/bin/fuchsia_tester.dart
index b23d98022e1..0e60a9619e6 100644
--- a/packages/flutter_tools/bin/fuchsia_tester.dart
+++ b/packages/flutter_tools/bin/fuchsia_tester.dart
@@ -105,7 +105,7 @@ Future<void> run(List<String> args) async {
     final Directory sdkRootDest =
         globals.fs.directory(globals.artifacts.getArtifactPath(Artifact.flutterPatchedSdkPath));
     sdkRootDest.createSync(recursive: true);
-    for (FileSystemEntity artifact in sdkRootSrc.listSync()) {
+    for (final FileSystemEntity artifact in sdkRootSrc.listSync()) {
       globals.fs.link(sdkRootDest.childFile(artifact.basename).path).createSync(artifact.path);
     }
     // TODO(tvolkert): Remove once flutter_tester no longer looks for this.
@@ -136,7 +136,7 @@ Future<void> run(List<String> args) async {
     final Map<String, String> tests = <String, String>{};
     final List<Map<String, dynamic>> jsonList = List<Map<String, dynamic>>.from(
       (json.decode(globals.fs.file(argResults[_kOptionTests]).readAsStringSync()) as List<dynamic>).cast<Map<String, dynamic>>());
-    for (Map<String, dynamic> map in jsonList) {
+    for (final Map<String, dynamic> map in jsonList) {
       final String source = globals.fs.file(map['source']).resolveSymbolicLinksSync();
       final String dill = globals.fs.file(map['dill']).resolveSymbolicLinksSync();
       tests[source] = dill;
diff --git a/packages/flutter_tools/lib/src/android/android_builder.dart b/packages/flutter_tools/lib/src/android/android_builder.dart
index 17b5d5dc6c7..40ddbd65633 100644
--- a/packages/flutter_tools/lib/src/android/android_builder.dart
+++ b/packages/flutter_tools/lib/src/android/android_builder.dart
@@ -68,7 +68,7 @@ class _AndroidBuilderImpl extends AndroidBuilder {
         // Module projects artifacts are located in `build/host`.
         outputDirectory = outputDirectory.childDirectory('host');
       }
-      for (AndroidBuildInfo androidBuildInfo in androidBuildInfo) {
+      for (final AndroidBuildInfo androidBuildInfo in androidBuildInfo) {
         await buildGradleAar(
           project: project,
           androidBuildInfo: androidBuildInfo,
diff --git a/packages/flutter_tools/lib/src/android/android_device.dart b/packages/flutter_tools/lib/src/android/android_device.dart
index 3b8d6b58bdf..384e3b09eb0 100644
--- a/packages/flutter_tools/lib/src/android/android_device.dart
+++ b/packages/flutter_tools/lib/src/android/android_device.dart
@@ -732,7 +732,7 @@ class AndroidDevice extends Device {
 Map<String, String> parseAdbDeviceProperties(String str) {
   final Map<String, String> properties = <String, String>{};
   final RegExp propertyExp = RegExp(r'\[(.*?)\]: \[(.*?)\]');
-  for (Match match in propertyExp.allMatches(str)) {
+  for (final Match match in propertyExp.allMatches(str)) {
     properties[match.group(1)] = match.group(2);
   }
   return properties;
@@ -932,7 +932,7 @@ void parseADBDeviceOutput(
     return;
   }
 
-  for (String line in text.trim().split('\n')) {
+  for (final String line in text.trim().split('\n')) {
     // Skip lines like: * daemon started successfully *
     if (line.startsWith('* daemon ')) {
       continue;
@@ -958,7 +958,7 @@ void parseADBDeviceOutput(
       final Map<String, String> info = <String, String>{};
       if (rest != null && rest.isNotEmpty) {
         rest = rest.trim();
-        for (String data in rest.split(' ')) {
+        for (final String data in rest.split(' ')) {
           if (data.contains(':')) {
             final List<String> fields = data.split(':');
             info[fields[0]] = fields[1];
@@ -1165,7 +1165,7 @@ class _AndroidDevicePortForwarder extends DevicePortForwarder {
     }
 
     final List<String> lines = LineSplitter.split(stdout).toList();
-    for (String line in lines) {
+    for (final String line in lines) {
       if (!line.startsWith(device.id)) {
         continue;
       }
@@ -1260,7 +1260,7 @@ class _AndroidDevicePortForwarder extends DevicePortForwarder {
 
   @override
   Future<void> dispose() async {
-    for (ForwardedPort port in forwardedPorts) {
+    for (final ForwardedPort port in forwardedPorts) {
       await unforward(port);
     }
   }
diff --git a/packages/flutter_tools/lib/src/android/android_emulator.dart b/packages/flutter_tools/lib/src/android/android_emulator.dart
index 5a7a04eb292..b7c0557d200 100644
--- a/packages/flutter_tools/lib/src/android/android_emulator.dart
+++ b/packages/flutter_tools/lib/src/android/android_emulator.dart
@@ -85,7 +85,7 @@ List<AndroidEmulator> getEmulatorAvds() {
 /// Parse the given `emulator -list-avds` output in [text], and fill out the given list
 /// of emulators by reading information from the relevant ini files.
 void extractEmulatorAvdInfo(String text, List<AndroidEmulator> emulators) {
-  for (String id in text.trim().split('\n').where((String l) => l != '')) {
+  for (final String id in text.trim().split('\n').where((String l) => l != '')) {
     emulators.add(_loadEmulatorInfo(id));
   }
 }
@@ -125,7 +125,7 @@ Map<String, String> parseIniLines(List<String> contents) {
       // Split into name/value
       .map<List<String>>((String l) => l.split('='));
 
-  for (List<String> property in properties) {
+  for (final List<String> property in properties) {
     results[property[0].trim()] = property[1].trim();
   }
 
diff --git a/packages/flutter_tools/lib/src/android/android_sdk.dart b/packages/flutter_tools/lib/src/android/android_sdk.dart
index 7c4ab747cf0..50fc605fee3 100644
--- a/packages/flutter_tools/lib/src/android/android_sdk.dart
+++ b/packages/flutter_tools/lib/src/android/android_sdk.dart
@@ -215,7 +215,7 @@ class AndroidNdk {
           .map<String>((String line) => line.trim())
           .where((String line) => line.isNotEmpty);
       final Map<String, String> properties = <String, String>{};
-      for (String line in propertiesFileLines) {
+      for (final String line in propertiesFileLines) {
         final List<String> parts = line.split(' = ');
         if (parts.length == 2) {
           properties[parts[0]] = parts[1];
diff --git a/packages/flutter_tools/lib/src/android/android_studio.dart b/packages/flutter_tools/lib/src/android/android_studio.dart
index 32014e265f4..f7ebfb42877 100644
--- a/packages/flutter_tools/lib/src/android/android_studio.dart
+++ b/packages/flutter_tools/lib/src/android/android_studio.dart
@@ -183,7 +183,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
             .directory(path)
             .listSync(followLinks: false)
             .whereType<Directory>();
-        for (Directory directory in directories) {
+        for (final Directory directory in directories) {
           final String name = directory.basename;
           // An exact match, or something like 'Android Studio 3.0 Preview.app'.
           if (name.startsWith('Android Studio') && name.endsWith('.app')) {
@@ -236,7 +236,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
     // Read all $HOME/.AndroidStudio*/system/.home files. There may be several
     // pointing to the same installation, so we grab only the latest one.
     if (homeDirPath != null && globals.fs.directory(homeDirPath).existsSync()) {
-      for (FileSystemEntity entity in globals.fs.directory(homeDirPath).listSync(followLinks: false)) {
+      for (final FileSystemEntity entity in globals.fs.directory(homeDirPath).listSync(followLinks: false)) {
         if (entity is Directory && entity.basename.startsWith('.AndroidStudio')) {
           final AndroidStudio studio = AndroidStudio.fromHomeDot(entity);
           if (studio != null && !_hasStudioAt(studio.directory, newerThan: studio.version)) {
diff --git a/packages/flutter_tools/lib/src/android/gradle.dart b/packages/flutter_tools/lib/src/android/gradle.dart
index 676599a8fd6..82364a1595f 100644
--- a/packages/flutter_tools/lib/src/android/gradle.dart
+++ b/packages/flutter_tools/lib/src/android/gradle.dart
@@ -116,7 +116,7 @@ bool _isSupportedVersion(AndroidProject project) {
   if (!appGradle.existsSync()) {
     return false;
   }
-  for (String line in appGradle.readAsLinesSync()) {
+  for (final String line in appGradle.readAsLinesSync()) {
     if (line.contains(RegExp(r'apply from: .*/flutter.gradle')) ||
         line.contains("def flutterPluginVersion = 'managed'")) {
       return true;
@@ -184,7 +184,7 @@ void createSettingsAarGradle(Directory androidDirectory) {
   existingVariants.add(settingsAarContent);
 
   bool exactMatch = false;
-  for (String fileContentVariant in existingVariants) {
+  for (final String fileContentVariant in existingVariants) {
     if (currentFileContent.trim() == fileContentVariant.trim()) {
       exactMatch = true;
       break;
@@ -465,7 +465,7 @@ Future<void> buildGradleApp({
   final File apkShaFile = apkDirectory.childFile('app.apk.sha1');
   apkShaFile.writeAsStringSync(_calculateSha(apkFiles.first));
 
-  for (File apkFile in apkFiles) {
+  for (final File apkFile in apkFiles) {
     final String appSize = (buildInfo.mode == BuildMode.debug)
       ? '' // Don't display the size when building a debug variant.
       : ' (${getSizeAsMB(apkFile.lengthSync())})';
@@ -618,7 +618,7 @@ ${globals.terminal.bolden('Consuming the Module')}
 
     dependencies {''');
 
-  for (String buildMode in buildModes) {
+  for (final String buildMode in buildModes) {
     globals.printStatus('''
       ${buildMode}Implementation '$androidPackage:flutter_$buildMode:$buildNumber''');
   }
@@ -647,7 +647,7 @@ ${globals.terminal.bolden('Consuming the Module')}
 
 String _hex(List<int> bytes) {
   final StringBuffer result = StringBuffer();
-  for (int part in bytes) {
+  for (final int part in bytes) {
     result.write('${part < 16 ? '0' : ''}${part.toRadixString(16)}');
   }
   return result.toString();
@@ -707,7 +707,7 @@ Future<void> buildPluginsAsAar(
     return;
   }
   final List<String> plugins = flutterPluginFile.readAsStringSync().split('\n');
-  for (String plugin in plugins) {
+  for (final String plugin in plugins) {
     final List<String> pluginParts = plugin.split('=');
     if (pluginParts.length != 2) {
       continue;
@@ -882,7 +882,7 @@ String _getLocalArtifactVersion(String pomPath) {
   }
   final Iterable<xml.XmlElement> project = document.findElements('project');
   assert(project.isNotEmpty);
-  for (xml.XmlElement versionElement in document.findAllElements('version')) {
+  for (final xml.XmlElement versionElement in document.findAllElements('version')) {
     if (versionElement.parent == project.first) {
       return versionElement.text;
     }
@@ -919,7 +919,7 @@ Directory _getLocalEngineRepo({
       'flutter_embedding_$buildMode.pom',
     )
   );
-  for (String artifact in const <String>['pom', 'jar']) {
+  for (final String artifact in const <String>['pom', 'jar']) {
     // The Android embedding artifacts.
     _createSymlink(
       globals.fs.path.join(
diff --git a/packages/flutter_tools/lib/src/android/gradle_errors.dart b/packages/flutter_tools/lib/src/android/gradle_errors.dart
index be2c00aa1df..9d5e63ba4e1 100644
--- a/packages/flutter_tools/lib/src/android/gradle_errors.dart
+++ b/packages/flutter_tools/lib/src/android/gradle_errors.dart
@@ -283,7 +283,7 @@ final GradleHandledError flavorUndefinedHandler = GradleHandledError(
     );
     // Extract build types and product flavors.
     final Set<String> variants = <String>{};
-    for (String task in tasksRunResult.stdout.split('\n')) {
+    for (final String task in tasksRunResult.stdout.split('\n')) {
       final Match match = _assembleTaskPattern.matchAsPrefix(task);
       if (match != null) {
         final String variant = match.group(1).toLowerCase();
diff --git a/packages/flutter_tools/lib/src/aot.dart b/packages/flutter_tools/lib/src/aot.dart
index bbf4c0e96b6..976eb09d228 100644
--- a/packages/flutter_tools/lib/src/aot.dart
+++ b/packages/flutter_tools/lib/src/aot.dart
@@ -89,7 +89,7 @@ class AotBuilder {
       if (platform == TargetPlatform.ios) {
         // Determine which iOS architectures to build for.
         final Map<DarwinArch, String> iosBuilds = <DarwinArch, String>{};
-        for (DarwinArch arch in iosBuildArchs) {
+        for (final DarwinArch arch in iosBuildArchs) {
           iosBuilds[arch] = globals.fs.path.join(outputPath, getNameForDarwinArch(arch));
         }
 
@@ -224,7 +224,7 @@ class AotBuilder {
     ));
     status?.stop();
     if (!result.success) {
-      for (ExceptionMeasurement measurement in result.exceptions.values) {
+      for (final ExceptionMeasurement measurement in result.exceptions.values) {
         globals.printError('Target ${measurement.target} failed: ${measurement.exception}',
           stackTrace: measurement.fatal
             ? measurement.stackTrace
diff --git a/packages/flutter_tools/lib/src/application_package.dart b/packages/flutter_tools/lib/src/application_package.dart
index 27625a3d26f..034f02d2fda 100644
--- a/packages/flutter_tools/lib/src/application_package.dart
+++ b/packages/flutter_tools/lib/src/application_package.dart
@@ -213,16 +213,16 @@ class AndroidApk extends ApplicationPackage {
     final String packageId = manifests.first.getAttribute('package');
 
     String launchActivity;
-    for (xml.XmlElement activity in document.findAllElements('activity')) {
+    for (final xml.XmlElement activity in document.findAllElements('activity')) {
       final String enabled = activity.getAttribute('android:enabled');
       if (enabled != null && enabled == 'false') {
         continue;
       }
 
-      for (xml.XmlElement element in activity.findElements('intent-filter')) {
+      for (final xml.XmlElement element in activity.findElements('intent-filter')) {
         String actionName = '';
         String categoryName = '';
-        for (xml.XmlNode node in element.children) {
+        for (final xml.XmlNode node in element.children) {
           if (node is! xml.XmlElement) {
             continue;
           }
@@ -511,7 +511,7 @@ class ApkManifestData {
   static bool isAttributeWithValuePresent(_Element baseElement,
       String childElement, String attributeName, String attributeValue) {
     final Iterable<_Element> allElements = baseElement.allElements(childElement);
-    for (_Element oneElement in allElements) {
+    for (final _Element oneElement in allElements) {
       final String elementAttributeValue = oneElement
           ?.firstAttribute(attributeName)
           ?.value;
@@ -535,7 +535,7 @@ class ApkManifestData {
     final _Element manifest = _Element.fromLine(lines[manifestLine], null);
     _Element currentElement = manifest;
 
-    for (String line in lines.skip(manifestLine)) {
+    for (final String line in lines.skip(manifestLine)) {
       final String trimLine = line.trimLeft();
       final int level = line.length - trimLine.length;
 
@@ -564,7 +564,7 @@ class ApkManifestData {
     final Iterable<_Element> activities = application.allElements('activity');
 
     _Element launchActivity;
-    for (_Element activity in activities) {
+    for (final _Element activity in activities) {
       final _Attribute enabled = activity.firstAttribute('android:enabled');
       final Iterable<_Element> intentFilters = activity.allElements('intent-filter');
       final bool isEnabledByDefault = enabled == null;
@@ -573,7 +573,7 @@ class ApkManifestData {
         continue;
       }
 
-      for (_Element element in intentFilters) {
+      for (final _Element element in intentFilters) {
         final bool isMainAction = isAttributeWithValuePresent(
             element, 'action', 'android:name', '"android.intent.action.MAIN"');
         if (!isMainAction) {
diff --git a/packages/flutter_tools/lib/src/artifacts.dart b/packages/flutter_tools/lib/src/artifacts.dart
index 60f6ef697ac..e9d7c46172c 100644
--- a/packages/flutter_tools/lib/src/artifacts.dart
+++ b/packages/flutter_tools/lib/src/artifacts.dart
@@ -509,7 +509,7 @@ class LocalEngineArtifacts extends Artifacts {
   String _genSnapshotPath() {
     const List<String> clangDirs = <String>['.', 'clang_x64', 'clang_x86', 'clang_i386'];
     final String genSnapshotName = _artifactToFileName(Artifact.genSnapshot);
-    for (String clangDir in clangDirs) {
+    for (final String clangDir in clangDirs) {
       final String genSnapshotPath = globals.fs.path.join(engineOutPath, clangDir, genSnapshotName);
       if (globals.processManager.canRun(genSnapshotPath)) {
         return genSnapshotPath;
diff --git a/packages/flutter_tools/lib/src/asset.dart b/packages/flutter_tools/lib/src/asset.dart
index 3c151c949fb..d1a47064a81 100644
--- a/packages/flutter_tools/lib/src/asset.dart
+++ b/packages/flutter_tools/lib/src/asset.dart
@@ -89,11 +89,11 @@ class _ManifestAssetBundle implements AssetBundle {
       return true;
     }
 
-    for (Directory directory in _wildcardDirectories.values) {
+    for (final Directory directory in _wildcardDirectories.values) {
       if (!directory.existsSync()) {
         return true; // directory was deleted.
       }
-      for (File file in directory.listSync().whereType<File>()) {
+      for (final File file in directory.listSync().whereType<File>()) {
         final DateTime dateTime = file.statSync().modified;
         if (dateTime == null) {
           continue;
@@ -166,7 +166,7 @@ class _ManifestAssetBundle implements AssetBundle {
     );
 
     // Add fonts and assets from packages.
-    for (String packageName in packageMap.map.keys) {
+    for (final String packageName in packageMap.map.keys) {
       final Uri package = packageMap.map[packageName];
       if (package != null && package.scheme == 'file') {
         final String packageManifestPath = globals.fs.path.fromUri(package.resolve('../pubspec.yaml'));
@@ -204,7 +204,7 @@ class _ManifestAssetBundle implements AssetBundle {
 
     // Save the contents of each image, image variant, and font
     // asset in entries.
-    for (_Asset asset in assetVariants.keys) {
+    for (final _Asset asset in assetVariants.keys) {
       if (!asset.assetFileExists && assetVariants[asset].isEmpty) {
         globals.printStatus('Error detected in pubspec.yaml:', emphasis: true);
         globals.printError('No file or variants found for $asset.\n');
@@ -220,7 +220,7 @@ class _ManifestAssetBundle implements AssetBundle {
         assert(!assetVariants[asset].contains(asset));
         assetVariants[asset].insert(0, asset);
       }
-      for (_Asset variant in assetVariants[asset]) {
+      for (final _Asset variant in assetVariants[asset]) {
         assert(variant.assetFileExists);
         entries[variant.entryUri.path] ??= DevFSFileContent(variant.assetFile);
       }
@@ -230,13 +230,13 @@ class _ManifestAssetBundle implements AssetBundle {
       if (flutterManifest.usesMaterialDesign && includeDefaultFonts)
         ..._getMaterialAssets(_fontSetMaterial),
     ];
-    for (_Asset asset in materialAssets) {
+    for (final _Asset asset in materialAssets) {
       assert(asset.assetFileExists);
       entries[asset.entryUri.path] ??= DevFSFileContent(asset.assetFile);
     }
 
     // Update wildcard directories we we can detect changes in them.
-    for (Uri uri in wildcardDirectories) {
+    for (final Uri uri in wildcardDirectories) {
       _wildcardDirectories[uri] ??= globals.fs.directory(uri);
     }
 
@@ -321,8 +321,8 @@ List<Map<String, dynamic>> _getMaterialFonts(String fontSet) {
 List<_Asset> _getMaterialAssets(String fontSet) {
   final List<_Asset> result = <_Asset>[];
 
-  for (Map<String, dynamic> family in _getMaterialFonts(fontSet)) {
-    for (Map<dynamic, dynamic> font in family['fonts']) {
+  for (final Map<String, dynamic> family in _getMaterialFonts(fontSet)) {
+    for (final Map<dynamic, dynamic> font in family['fonts']) {
       final Uri entryUri = globals.fs.path.toUri(font['asset'] as String);
       result.add(_Asset(
         baseDir: globals.fs.path.join(Cache.flutterRoot, 'bin', 'cache', 'artifacts', 'material_fonts'),
@@ -358,7 +358,7 @@ DevFSContent _obtainLicenses(
   // sources, and might need to include a license for each one.)
   final Map<String, Set<String>> packageLicenses = <String, Set<String>>{};
   final Set<String> allPackages = <String>{};
-  for (String packageName in packageMap.map.keys) {
+  for (final String packageName in packageMap.map.keys) {
     final Uri package = packageMap.map[packageName];
     if (package == null || package.scheme != 'file') {
       continue;
@@ -369,7 +369,7 @@ DevFSContent _obtainLicenses(
     }
     final List<String> rawLicenses =
         file.readAsStringSync().split(_licenseSeparator);
-    for (String rawLicense in rawLicenses) {
+    for (final String rawLicense in rawLicenses) {
       List<String> packageNames;
       String licenseText;
       if (rawLicenses.length > 1) {
@@ -421,9 +421,9 @@ DevFSContent _createAssetManifest(Map<_Asset, List<_Asset>> assetVariants) {
       .keys.toList()
     ..sort(_byBasename);
 
-  for (_Asset main in sortedKeys) {
+  for (final _Asset main in sortedKeys) {
     jsonObject[main.entryUri.path] = <String>[
-      for (_Asset variant in assetVariants[main])
+      for (final _Asset variant in assetVariants[main])
         variant.entryUri.path,
     ];
   }
@@ -458,9 +458,9 @@ List<Font> _parsePackageFonts(
   PackageMap packageMap,
 ) {
   final List<Font> packageFonts = <Font>[];
-  for (Font font in manifest.fonts) {
+  for (final Font font in manifest.fonts) {
     final List<FontAsset> packageFontAssets = <FontAsset>[];
-    for (FontAsset fontAsset in font.fontAssets) {
+    for (final FontAsset fontAsset in font.fontAssets) {
       final Uri assetUri = fontAsset.assetUri;
       if (assetUri.pathSegments.first == 'packages' &&
           !globals.fs.isFileSync(globals.fs.path.fromUri(packageMap.map[packageName].resolve('../${assetUri.path}')))) {
@@ -513,7 +513,7 @@ class _AssetDirectoryCache {
 
     if (_cache[directory] == null) {
       final List<String> paths = <String>[];
-      for (FileSystemEntity entity in globals.fs.directory(directory).listSync(recursive: true)) {
+      for (final FileSystemEntity entity in globals.fs.directory(directory).listSync(recursive: true)) {
         final String path = entity.path;
         if (globals.fs.isFileSync(path) && !_excluded.any((String exclude) => path.startsWith(exclude))) {
           paths.add(path);
@@ -521,7 +521,7 @@ class _AssetDirectoryCache {
       }
 
       final Map<String, List<String>> variants = <String, List<String>>{};
-      for (String path in paths) {
+      for (final String path in paths) {
         final String variantName = globals.fs.path.basename(path);
         if (directory == globals.fs.path.dirname(path)) {
           continue;
@@ -572,7 +572,7 @@ Map<_Asset, List<_Asset>> _parseAssets(
   final Map<_Asset, List<_Asset>> result = <_Asset, List<_Asset>>{};
 
   final _AssetDirectoryCache cache = _AssetDirectoryCache(excludeDirs);
-  for (Uri assetUri in flutterManifest.assets) {
+  for (final Uri assetUri in flutterManifest.assets) {
     if (assetUri.toString().endsWith('/')) {
       wildcardDirectories.add(assetUri);
       _parseAssetsFromFolder(packageMap, flutterManifest, assetBase,
@@ -586,8 +586,8 @@ Map<_Asset, List<_Asset>> _parseAssets(
   }
 
   // Add assets referenced in the fonts section of the manifest.
-  for (Font font in flutterManifest.fonts) {
-    for (FontAsset fontAsset in font.fontAssets) {
+  for (final Font font in flutterManifest.fonts) {
+    for (final FontAsset fontAsset in font.fontAssets) {
       final _Asset baseAsset = _resolveAsset(
         packageMap,
         assetBase,
@@ -626,7 +626,7 @@ void _parseAssetsFromFolder(
 
   final List<FileSystemEntity> lister = globals.fs.directory(directoryPath).listSync();
 
-  for (FileSystemEntity entity in lister) {
+  for (final FileSystemEntity entity in lister) {
     if (entity is File) {
       final String relativePath = globals.fs.path.relative(entity.path, from: assetBase);
 
@@ -655,7 +655,7 @@ void _parseAssetFromFile(
     packageName,
   );
   final List<_Asset> variants = <_Asset>[];
-  for (String path in cache.variantsFor(asset.assetFile.path)) {
+  for (final String path in cache.variantsFor(asset.assetFile.path)) {
     final String relativePath = globals.fs.path.relative(path, from: asset.baseDir);
     final Uri relativeUri = globals.fs.path.toUri(relativePath);
     final Uri entryUri = asset.symbolicPrefixUri == null
diff --git a/packages/flutter_tools/lib/src/base/build.dart b/packages/flutter_tools/lib/src/base/build.dart
index 9d5c8fce23a..15e7bc9e625 100644
--- a/packages/flutter_tools/lib/src/base/build.dart
+++ b/packages/flutter_tools/lib/src/base/build.dart
@@ -185,7 +185,7 @@ class AOTSnapshotter {
     final bool stripSymbols = platform == TargetPlatform.ios && buildMode == BuildMode.release && bitcode;
     if (stripSymbols) {
       final IOSink sink = globals.fs.file('$assembly.stripped.S').openWrite();
-      for (String line in globals.fs.file(assembly).readAsLinesSync()) {
+      for (final String line in globals.fs.file(assembly).readAsLinesSync()) {
         if (line.startsWith('.section __DWARF')) {
           break;
         }
diff --git a/packages/flutter_tools/lib/src/base/file_system.dart b/packages/flutter_tools/lib/src/base/file_system.dart
index 4100d778083..6e3ccce7b23 100644
--- a/packages/flutter_tools/lib/src/base/file_system.dart
+++ b/packages/flutter_tools/lib/src/base/file_system.dart
@@ -42,7 +42,7 @@ void copyDirectorySync(
     destDir.createSync(recursive: true);
   }
 
-  for (FileSystemEntity entity in srcDir.listSync()) {
+  for (final FileSystemEntity entity in srcDir.listSync()) {
     final String newPath = destDir.fileSystem.path.join(destDir.path, entity.basename);
     if (entity is File) {
       final File newFile = destDir.fileSystem.file(newPath);
diff --git a/packages/flutter_tools/lib/src/base/fingerprint.dart b/packages/flutter_tools/lib/src/base/fingerprint.dart
index 5fc0b2fb2d4..9ef80c7380f 100644
--- a/packages/flutter_tools/lib/src/base/fingerprint.dart
+++ b/packages/flutter_tools/lib/src/base/fingerprint.dart
@@ -87,7 +87,7 @@ class Fingerprinter {
   List<String> _getPaths() {
     final Set<String> paths = <String>{
       ..._paths,
-      for (String depfilePath in _depfilePaths)
+      for (final String depfilePath in _depfilePaths)
         ...readDepfile(depfilePath),
     };
     final FingerprintPathFilter filter = _pathFilter ?? (String path) => true;
@@ -108,7 +108,7 @@ class Fingerprint {
     }
 
     _checksums = <String, String>{};
-    for (File file in files) {
+    for (final File file in files) {
       final List<int> bytes = file.readAsBytesSync();
       _checksums[file.path] = md5.convert(bytes).toString();
     }
diff --git a/packages/flutter_tools/lib/src/base/net.dart b/packages/flutter_tools/lib/src/base/net.dart
index 150e1a100fe..38fa19ccf67 100644
--- a/packages/flutter_tools/lib/src/base/net.dart
+++ b/packages/flutter_tools/lib/src/base/net.dart
@@ -187,7 +187,7 @@ class _MemoryIOSink implements IOSink {
   @override
   void writeAll(Iterable<dynamic> objects, [ String separator = '' ]) {
     bool addSeparator = false;
-    for (dynamic object in objects) {
+    for (final dynamic object in objects) {
       if (addSeparator) {
         write(separator);
       }
diff --git a/packages/flutter_tools/lib/src/base/os.dart b/packages/flutter_tools/lib/src/base/os.dart
index f07c75839f4..b0cd1d4d53e 100644
--- a/packages/flutter_tools/lib/src/base/os.dart
+++ b/packages/flutter_tools/lib/src/base/os.dart
@@ -248,7 +248,7 @@ class _WindowsUtils extends OperatingSystemUtils {
   @override
   void zip(Directory data, File zipFile) {
     final Archive archive = Archive();
-    for (FileSystemEntity entity in data.listSync(recursive: true)) {
+    for (final FileSystemEntity entity in data.listSync(recursive: true)) {
       if (entity is! File) {
         continue;
       }
@@ -299,7 +299,7 @@ class _WindowsUtils extends OperatingSystemUtils {
   }
 
   void _unpackArchive(Archive archive, Directory targetDirectory) {
-    for (ArchiveFile archiveFile in archive.files) {
+    for (final ArchiveFile archiveFile in archive.files) {
       // The archive package doesn't correctly set isFile.
       if (!archiveFile.isFile || archiveFile.name.endsWith('/')) {
         continue;
diff --git a/packages/flutter_tools/lib/src/base/process.dart b/packages/flutter_tools/lib/src/base/process.dart
index e2e612863a2..fb634e8dc62 100644
--- a/packages/flutter_tools/lib/src/base/process.dart
+++ b/packages/flutter_tools/lib/src/base/process.dart
@@ -78,11 +78,11 @@ Future<void> runShutdownHooks() async {
   globals.printTrace('Running shutdown hooks');
   _shutdownHooksRunning = true;
   try {
-    for (ShutdownStage stage in _shutdownHooks.keys.toList()..sort()) {
+    for (final ShutdownStage stage in _shutdownHooks.keys.toList()..sort()) {
       globals.printTrace('Shutdown hook priority ${stage.priority}');
       final List<ShutdownHook> hooks = _shutdownHooks.remove(stage);
       final List<Future<dynamic>> futures = <Future<dynamic>>[];
-      for (ShutdownHook shutdownHook in hooks) {
+      for (final ShutdownHook shutdownHook in hooks) {
         final FutureOr<dynamic> result = shutdownHook();
         if (result is Future<dynamic>) {
           futures.add(result);
diff --git a/packages/flutter_tools/lib/src/base/signals.dart b/packages/flutter_tools/lib/src/base/signals.dart
index 3899d4f3a91..28b9e67e866 100644
--- a/packages/flutter_tools/lib/src/base/signals.dart
+++ b/packages/flutter_tools/lib/src/base/signals.dart
@@ -114,7 +114,7 @@ class _DefaultSignals implements Signals {
   }
 
   Future<void> _handleSignal(ProcessSignal s) async {
-    for (SignalHandler handler in _handlersList[s]) {
+    for (final SignalHandler handler in _handlersList[s]) {
       try {
         await asyncGuard<void>(() async => handler(s));
       } catch (e) {
diff --git a/packages/flutter_tools/lib/src/base/utils.dart b/packages/flutter_tools/lib/src/base/utils.dart
index 0cfcc72fed3..b246d1016e6 100644
--- a/packages/flutter_tools/lib/src/base/utils.dart
+++ b/packages/flutter_tools/lib/src/base/utils.dart
@@ -319,7 +319,7 @@ String wrapText(String text, { int columnWidth, int hangingIndent, int indent, b
   hangingIndent ??= 0;
   final List<String> splitText = text.split('\n');
   final List<String> result = <String>[];
-  for (String line in splitText) {
+  for (final String line in splitText) {
     String trimmedText = line.trimLeft();
     final String leadingWhitespace = line.substring(0, line.length - trimmedText.length);
     List<String> notIndented;
@@ -433,7 +433,7 @@ List<String> _wrapTextAsLines(String text, { int start = 0, int columnWidth, boo
     final RegExp characterOrCode = RegExp('(\u001b\[[0-9;]*m|.)', multiLine: true);
     List<_AnsiRun> result = <_AnsiRun>[];
     final StringBuffer current = StringBuffer();
-    for (Match match in characterOrCode.allMatches(input)) {
+    for (final Match match in characterOrCode.allMatches(input)) {
       current.write(match[0]);
       if (match[0].length < 4) {
         // This is a regular character, write it out.
@@ -461,7 +461,7 @@ List<String> _wrapTextAsLines(String text, { int start = 0, int columnWidth, boo
 
   final List<String> result = <String>[];
   final int effectiveLength = max(columnWidth - start, kMinColumnWidth);
-  for (String line in text.split('\n')) {
+  for (final String line in text.split('\n')) {
     // If the line is short enough, even with ANSI codes, then we can just add
     // add it and move on.
     if (line.length <= effectiveLength || !shouldWrap) {
diff --git a/packages/flutter_tools/lib/src/base/version.dart b/packages/flutter_tools/lib/src/base/version.dart
index 5e794354367..e89772c463e 100644
--- a/packages/flutter_tools/lib/src/base/version.dart
+++ b/packages/flutter_tools/lib/src/base/version.dart
@@ -52,7 +52,7 @@ class Version implements Comparable<Version> {
   /// This is the highest-numbered stable version.
   static Version primary(List<Version> versions) {
     Version primary;
-    for (Version version in versions) {
+    for (final Version version in versions) {
       if (primary == null || (version > primary)) {
         primary = version;
       }
diff --git a/packages/flutter_tools/lib/src/build_runner/build_runner.dart b/packages/flutter_tools/lib/src/build_runner/build_runner.dart
index 082605f07a0..0a9334ed791 100644
--- a/packages/flutter_tools/lib/src/build_runner/build_runner.dart
+++ b/packages/flutter_tools/lib/src/build_runner/build_runner.dart
@@ -78,7 +78,7 @@ class BuildRunner extends CodeGenerator {
       stringBuffer.writeln('dependencies:');
       final YamlMap builders = flutterProject.builders;
       if (builders != null) {
-        for (String name in builders.keys.cast<String>()) {
+        for (final String name in builders.keys.cast<String>()) {
           final Object node = builders[name];
           // For relative paths, make sure it is accounted for
           // parent directories.
diff --git a/packages/flutter_tools/lib/src/build_runner/web_compilation_delegate.dart b/packages/flutter_tools/lib/src/build_runner/web_compilation_delegate.dart
index de5f20d416a..df9c642a4e8 100644
--- a/packages/flutter_tools/lib/src/build_runner/web_compilation_delegate.dart
+++ b/packages/flutter_tools/lib/src/build_runner/web_compilation_delegate.dart
@@ -60,7 +60,7 @@ class BuildRunnerWebCompilationProxy extends WebCompilationProxy {
     );
     client.startBuild();
     bool success = true;
-    await for (BuildResults results in client.buildResults) {
+    await for (final BuildResults results in client.buildResults) {
       final BuildResult result = results.results.firstWhere((BuildResult result) {
         return result.target == 'web';
       });
@@ -81,7 +81,7 @@ class BuildRunnerWebCompilationProxy extends WebCompilationProxy {
       final Iterable<Directory> childDirectories = rootDirectory
         .listSync()
         .whereType<Directory>();
-      for (Directory childDirectory in childDirectories) {
+      for (final Directory childDirectory in childDirectories) {
         final String path = globals.fs.path.join(testOutputDir, 'packages',
             globals.fs.path.basename(childDirectory.path));
         copyDirectorySync(childDirectory.childDirectory('lib'), globals.fs.directory(path));
@@ -135,7 +135,7 @@ class MultirootFileBasedAssetReader extends core.FileBasedAssetReader {
   Stream<AssetId> findAssets(Glob glob, {String package}) async* {
     if (package == null || packageGraph.root.name == package) {
       final String generatedRoot = globals.fs.path.join(generatedDirectory.path, packageGraph.root.name);
-      await for (io.FileSystemEntity entity in glob.list(followLinks: true, root: packageGraph.root.path)) {
+      await for (final io.FileSystemEntity entity in glob.list(followLinks: true, root: packageGraph.root.path)) {
         if (entity is io.File && _isNotHidden(entity) && !globals.fs.path.isWithin(generatedRoot, entity.path)) {
           yield _fileToAssetId(entity, packageGraph.root);
         }
@@ -143,7 +143,7 @@ class MultirootFileBasedAssetReader extends core.FileBasedAssetReader {
       if (!globals.fs.isDirectorySync(generatedRoot)) {
         return;
       }
-      await for (io.FileSystemEntity entity in glob.list(followLinks: true, root: generatedRoot)) {
+      await for (final io.FileSystemEntity entity in glob.list(followLinks: true, root: generatedRoot)) {
         if (entity is io.File && _isNotHidden(entity)) {
           yield _fileToAssetId(entity, packageGraph.root, globals.fs.path.relative(generatedRoot), true);
         }
diff --git a/packages/flutter_tools/lib/src/build_runner/web_fs.dart b/packages/flutter_tools/lib/src/build_runner/web_fs.dart
index 1e9c0bd5c68..f4c97b68958 100644
--- a/packages/flutter_tools/lib/src/build_runner/web_fs.dart
+++ b/packages/flutter_tools/lib/src/build_runner/web_fs.dart
@@ -154,7 +154,7 @@ class WebFs {
       return true;
     }
     _client.startBuild();
-    await for (BuildResults results in _client.buildResults) {
+    await for (final BuildResults results in _client.buildResults) {
       final BuildResult result = results.results.firstWhere((BuildResult result) {
         return result.target == kBuildTargetName;
       });
@@ -367,7 +367,7 @@ class ReleaseAssetServer extends AssetServer {
   @override
   Future<Response> handle(Request request) async {
     Uri fileUri;
-    for (Uri uri in _searchPaths) {
+    for (final Uri uri in _searchPaths) {
       final Uri potential = uri.resolve(request.url.path);
       if (potential == null || !globals.fs.isFileSync(potential.toFilePath())) {
         continue;
@@ -445,7 +445,7 @@ class DebugAssetServer extends AssetServer {
           final Archive archive = TarDecoder().decodeBytes(dart2jsArchive.readAsBytesSync());
           partFiles = globals.fs.systemTempDirectory.createTempSync('flutter_tool.')
             ..createSync();
-          for (ArchiveFile file in archive) {
+          for (final ArchiveFile file in archive) {
             partFiles.childFile(file.name).writeAsBytesSync(file.content as List<int>);
           }
         }
@@ -664,7 +664,7 @@ class BuildDaemonCreator {
       '--define', 'flutter_tools:shell=initializePlatform=$initializePlatform',
       // The following will cause build runner to only build tests that were requested.
       if (testTargets != null && testTargets.hasBuildFilters)
-        for (String buildFilter in testTargets.buildFilters)
+        for (final String buildFilter in testTargets.buildFilters)
           '--build-filter=$buildFilter',
     ];
 
diff --git a/packages/flutter_tools/lib/src/build_system/build_system.dart b/packages/flutter_tools/lib/src/build_system/build_system.dart
index 1f67a56a76a..6f4f85a8f43 100644
--- a/packages/flutter_tools/lib/src/build_system/build_system.dart
+++ b/packages/flutter_tools/lib/src/build_system/build_system.dart
@@ -138,7 +138,7 @@ abstract class Target {
       inputsFiles.sources,
       outputFiles.sources,
       <Node>[
-        for (Target target in dependencies) target._toNode(environment),
+        for (final Target target in dependencies) target._toNode(environment),
       ],
       environment,
       inputsFiles.containsNewDepfile,
@@ -160,11 +160,11 @@ abstract class Target {
   ) {
     final File stamp = _findStampFile(environment);
     final List<String> inputPaths = <String>[];
-    for (File input in inputs) {
+    for (final File input in inputs) {
       inputPaths.add(input.path);
     }
     final List<String> outputPaths = <String>[];
-    for (File output in outputs) {
+    for (final File output in outputs) {
       outputPaths.add(output.path);
     }
     final Map<String, Object> result = <String, Object>{
@@ -207,13 +207,13 @@ abstract class Target {
     return <String, Object>{
       'name': name,
       'dependencies': <String>[
-        for (Target target in dependencies) target.name,
+        for (final Target target in dependencies) target.name,
       ],
       'inputs': <String>[
-        for (File file in resolveInputs(environment).sources) file.path,
+        for (final File file in resolveInputs(environment).sources) file.path,
       ],
       'outputs': <String>[
-        for (File file in resolveOutputs(environment).sources) file.path,
+        for (final File file in resolveOutputs(environment).sources) file.path,
       ],
       'stamp': _findStampFile(environment).absolute.path,
     };
@@ -229,7 +229,7 @@ abstract class Target {
     List<String> depfiles, Environment environment, { bool implicit = true, bool inputs = true,
   }) {
     final SourceVisitor collector = SourceVisitor(environment, inputs);
-    for (Source source in config) {
+    for (final Source source in config) {
       source.accept(collector);
     }
     depfiles.forEach(collector.visitDepfile);
@@ -292,7 +292,7 @@ class Environment {
     String buildPrefix;
     final List<String> keys = defines.keys.toList()..sort();
     final StringBuffer buffer = StringBuffer();
-    for (String key in keys) {
+    for (final String key in keys) {
       buffer.write(key);
       buffer.write(defines[key]);
     }
@@ -502,10 +502,10 @@ class _BuildInstance {
     // these files are included as both inputs and outputs then it isn't
     // possible to construct a DAG describing the build.
     void updateGraph() {
-      for (File output in node.outputs) {
+      for (final File output in node.outputs) {
         outputFiles[output.path] = output;
       }
-      for (File input in node.inputs) {
+      for (final File input in node.inputs) {
         final String resolvedPath = input.absolute.path;
         if (outputFiles.containsKey(resolvedPath)) {
           continue;
@@ -550,7 +550,7 @@ class _BuildInstance {
 
       // Delete outputs from previous stages that are no longer a part of the
       // build.
-      for (String previousOutput in node.previousOutputs) {
+      for (final String previousOutput in node.previousOutputs) {
         if (outputFiles.containsKey(previousOutput)) {
           continue;
         }
@@ -614,7 +614,7 @@ void checkCycles(Target initial) {
     }
     visited.add(target);
     stack.add(target);
-    for (Target dependency in target.dependencies) {
+    for (final Target dependency in target.dependencies) {
       checkInternal(dependency, visited, stack);
     }
     stack.remove(target);
@@ -627,7 +627,7 @@ void verifyOutputDirectories(List<File> outputs, Environment environment, Target
   final String buildDirectory = environment.buildDir.resolveSymbolicLinksSync();
   final String projectDirectory = environment.projectDir.resolveSymbolicLinksSync();
   final List<File> missingOutputs = <File>[];
-  for (File sourceFile in outputs) {
+  for (final File sourceFile in outputs) {
     if (!sourceFile.existsSync()) {
       missingOutputs.add(sourceFile);
       continue;
@@ -733,13 +733,13 @@ class Node {
     FileHashStore fileHashStore,
   ) async {
     final Set<String> currentOutputPaths = <String>{
-      for (File file in outputs) file.path,
+      for (final File file in outputs) file.path,
     };
     // For each input, first determine if we've already computed the hash
     // for it. Then collect it to be sent off for hashing as a group.
     final List<File> sourcesToHash = <File>[];
     final List<File> missingInputs = <File>[];
-    for (File file in inputs) {
+    for (final File file in inputs) {
       if (!file.existsSync()) {
         missingInputs.add(file);
         continue;
@@ -760,7 +760,7 @@ class Node {
 
     // For each output, first determine if we've already computed the hash
     // for it. Then collect it to be sent off for hashing as a group.
-    for (String previousOutput in previousOutputs) {
+    for (final String previousOutput in previousOutputs) {
       // output paths changed.
       if (!currentOutputPaths.contains(previousOutput)) {
         _dirty = true;
diff --git a/packages/flutter_tools/lib/src/build_system/depfile.dart b/packages/flutter_tools/lib/src/build_system/depfile.dart
index 6e777af6bac..6ae60212b6e 100644
--- a/packages/flutter_tools/lib/src/build_system/depfile.dart
+++ b/packages/flutter_tools/lib/src/build_system/depfile.dart
@@ -31,7 +31,7 @@ class Depfile {
   /// file must be manually specified.
   factory Depfile.parseDart2js(File file, File output) {
     final List<File> inputs = <File>[];
-    for (String rawUri in file.readAsLinesSync()) {
+    for (final String rawUri in file.readAsLinesSync()) {
       if (rawUri.trim().isEmpty) {
         continue;
       }
@@ -72,7 +72,7 @@ class Depfile {
   }
 
   void _writeFilesToBuffer(List<File> files, StringBuffer buffer) {
-    for (File outputFile in files) {
+    for (final File outputFile in files) {
       if (globals.platform.isWindows) {
         // Paths in a depfile have to be escaped on windows.
         final String escapedPath = outputFile.path.replaceAll(r'\', r'\\');
diff --git a/packages/flutter_tools/lib/src/build_system/file_hash_store.dart b/packages/flutter_tools/lib/src/build_system/file_hash_store.dart
index 72925ee2e44..0879c7b3d98 100644
--- a/packages/flutter_tools/lib/src/build_system/file_hash_store.dart
+++ b/packages/flutter_tools/lib/src/build_system/file_hash_store.dart
@@ -24,7 +24,7 @@ class FileStorage {
     final int version = json['version'] as int;
     final List<Map<String, Object>> rawCachedFiles = (json['files'] as List<dynamic>).cast<Map<String, Object>>();
     final List<FileHash> cachedFiles = <FileHash>[
-      for (Map<String, Object> rawFile in rawCachedFiles) FileHash.fromJson(rawFile),
+      for (final Map<String, Object> rawFile in rawCachedFiles) FileHash.fromJson(rawFile),
     ];
     return FileStorage(version, cachedFiles);
   }
@@ -36,7 +36,7 @@ class FileStorage {
     final Map<String, Object> json = <String, Object>{
       'version': version,
       'files': <Object>[
-        for (FileHash file in files) file.toJson(),
+        for (final FileHash file in files) file.toJson(),
       ],
     };
     return utf8.encode(jsonEncode(json));
@@ -118,7 +118,7 @@ class FileHashStore {
       cacheFile.deleteSync();
       return;
     }
-    for (FileHash fileHash in fileStorage.files) {
+    for (final FileHash fileHash in fileStorage.files) {
       previousHashes[fileHash.path] = fileHash.hash;
     }
     globals.printTrace('Done initializing file store');
@@ -132,7 +132,7 @@ class FileHashStore {
       cacheFile.createSync(recursive: true);
     }
     final List<FileHash> fileHashes = <FileHash>[];
-    for (MapEntry<String, String> entry in currentHashes.entries) {
+    for (final MapEntry<String, String> entry in currentHashes.entries) {
       fileHashes.add(FileHash(entry.key, entry.value));
     }
     final FileStorage fileStorage = FileStorage(
@@ -158,7 +158,7 @@ class FileHashStore {
     final List<File> dirty = <File>[];
     final Pool openFiles = Pool(kMaxOpenFiles);
     await Future.wait(<Future<void>>[
-       for (File file in files) _hashFile(file, dirty, openFiles)
+       for (final File file in files) _hashFile(file, dirty, openFiles)
     ]);
     return dirty;
   }
diff --git a/packages/flutter_tools/lib/src/build_system/source.dart b/packages/flutter_tools/lib/src/build_system/source.dart
index eb35f959a65..e0df5cb4ed1 100644
--- a/packages/flutter_tools/lib/src/build_system/source.dart
+++ b/packages/flutter_tools/lib/src/build_system/source.dart
@@ -146,7 +146,7 @@ class SourceVisitor implements ResolvedFiles {
     if (!globals.fs.directory(filePath).existsSync()) {
       throw Exception('$filePath does not exist!');
     }
-    for (FileSystemEntity entity in globals.fs.directory(filePath).listSync()) {
+    for (final FileSystemEntity entity in globals.fs.directory(filePath).listSync()) {
       final String filename = globals.fs.path.basename(entity.path);
       if (wildcardSegments.isEmpty) {
         sources.add(globals.fs.file(entity.absolute));
diff --git a/packages/flutter_tools/lib/src/build_system/targets/ios.dart b/packages/flutter_tools/lib/src/build_system/targets/ios.dart
index 1d9152af0a0..032e270c694 100644
--- a/packages/flutter_tools/lib/src/build_system/targets/ios.dart
+++ b/packages/flutter_tools/lib/src/build_system/targets/ios.dart
@@ -59,7 +59,7 @@ abstract class AotAssemblyBase extends Target {
       // If we're building multiple iOS archs the binaries need to be lipo'd
       // together.
       final List<Future<int>> pending = <Future<int>>[];
-      for (DarwinArch iosArch in iosArchs) {
+      for (final DarwinArch iosArch in iosArchs) {
         pending.add(snapshotter.build(
           platform: targetPlatform,
           buildMode: buildMode,
diff --git a/packages/flutter_tools/lib/src/build_system/targets/linux.dart b/packages/flutter_tools/lib/src/build_system/targets/linux.dart
index 706b788472d..8375ecd9b75 100644
--- a/packages/flutter_tools/lib/src/build_system/targets/linux.dart
+++ b/packages/flutter_tools/lib/src/build_system/targets/linux.dart
@@ -59,7 +59,7 @@ class UnpackLinuxDebug extends Target {
     );
     // The native linux artifacts are composed of 6 files and a directory (listed above)
     // which need to be copied to the target directory.
-    for (String artifact in _kLinuxArtifacts) {
+    for (final String artifact in _kLinuxArtifacts) {
       final String entityPath = globals.fs.path.join(basePath, artifact);
       // If this artifact is a file, just copy the source over.
       if (globals.fs.isFileSync(entityPath)) {
@@ -79,7 +79,7 @@ class UnpackLinuxDebug extends Target {
       }
       // If the artifact is the directory cpp_client_wrapper, recursively
       // copy every file from it.
-      for (File input in globals.fs.directory(entityPath)
+      for (final File input in globals.fs.directory(entityPath)
           .listSync(recursive: true)
           .whereType<File>()) {
         final String outputPath = globals.fs.path.join(
diff --git a/packages/flutter_tools/lib/src/build_system/targets/web.dart b/packages/flutter_tools/lib/src/build_system/targets/web.dart
index 97e0a00350f..00d9f634935 100644
--- a/packages/flutter_tools/lib/src/build_system/targets/web.dart
+++ b/packages/flutter_tools/lib/src/build_system/targets/web.dart
@@ -170,7 +170,7 @@ class Dart2JSTarget extends Target {
         '-Ddart.vm.profile=true'
       else
         '-Ddart.vm.product=true',
-      for (String dartDefine in parseDartDefines(environment))
+      for (final String dartDefine in parseDartDefines(environment))
         '-D$dartDefine',
       environment.buildDir.childFile('main.dart').path,
     ]);
@@ -224,7 +224,7 @@ class WebReleaseBundle extends Target {
 
   @override
   Future<void> build(Environment environment) async {
-    for (File outputFile in environment.buildDir.listSync(recursive: true).whereType<File>()) {
+    for (final File outputFile in environment.buildDir.listSync(recursive: true).whereType<File>()) {
       if (!globals.fs.path.basename(outputFile.path).contains('main.dart.js')) {
         continue;
       }
diff --git a/packages/flutter_tools/lib/src/build_system/targets/windows.dart b/packages/flutter_tools/lib/src/build_system/targets/windows.dart
index 5b05aa13d93..ce1ee7b6045 100644
--- a/packages/flutter_tools/lib/src/build_system/targets/windows.dart
+++ b/packages/flutter_tools/lib/src/build_system/targets/windows.dart
@@ -41,7 +41,7 @@ class UnpackWindows extends Target {
   Future<void> build(Environment environment) async {
     // This path needs to match the prefix in the rule below.
     final String basePath = globals.artifacts.getArtifactPath(Artifact.windowsDesktopPath);
-    for (File input in globals.fs.directory(basePath)
+    for (final File input in globals.fs.directory(basePath)
         .listSync(recursive: true)
         .whereType<File>()) {
       final String outputPath = globals.fs.path.join(
diff --git a/packages/flutter_tools/lib/src/bundle.dart b/packages/flutter_tools/lib/src/bundle.dart
index 2a3c9382fb0..b49658704c1 100644
--- a/packages/flutter_tools/lib/src/bundle.dart
+++ b/packages/flutter_tools/lib/src/bundle.dart
@@ -126,7 +126,7 @@ Future<void> buildWithAssemble({
   final BuildResult result = await buildSystem.build(target, environment);
 
   if (!result.success) {
-    for (ExceptionMeasurement measurement in result.exceptions.values) {
+    for (final ExceptionMeasurement measurement in result.exceptions.values) {
         globals.printError('Target ${measurement.target} failed: ${measurement.exception}',
           stackTrace: measurement.fatal
             ? measurement.stackTrace
diff --git a/packages/flutter_tools/lib/src/cache.dart b/packages/flutter_tools/lib/src/cache.dart
index 821f4c2500c..4320f34d81f 100644
--- a/packages/flutter_tools/lib/src/cache.dart
+++ b/packages/flutter_tools/lib/src/cache.dart
@@ -108,7 +108,7 @@ class Cache {
       _artifacts.add(MacOSFuchsiaSDKArtifacts(this));
       _artifacts.add(FlutterRunnerSDKArtifacts(this));
       _artifacts.add(FlutterRunnerDebugSymbols(this));
-      for (String artifactName in IosUsbArtifacts.artifactNames) {
+      for (final String artifactName in IosUsbArtifacts.artifactNames) {
         _artifacts.add(IosUsbArtifacts(artifactName, this));
       }
     } else {
@@ -300,7 +300,7 @@ class Cache {
       return _dyLdLibEntry;
     }
     final List<String> paths = <String>[];
-    for (ArtifactSet artifact in _artifacts) {
+    for (final ArtifactSet artifact in _artifacts) {
       final Map<String, String> env = artifact.environment;
       if (env == null || !env.containsKey('DYLD_LIBRARY_PATH')) {
         continue;
@@ -378,7 +378,7 @@ class Cache {
     if (!_lockEnabled) {
       return;
     }
-    for (ArtifactSet artifact in _artifacts) {
+    for (final ArtifactSet artifact in _artifacts) {
       if (!requiredArtifacts.contains(artifact.developmentArtifact)) {
         globals.printTrace('Artifact $artifact is not required, skipping update.');
         continue;
@@ -409,7 +409,7 @@ class Cache {
     final bool includeAllPlatformsState = globals.cache.includeAllPlatforms;
     bool allAvailible = true;
     globals.cache.includeAllPlatforms = includeAllPlatforms;
-    for (ArtifactSet cachedArtifact in _artifacts) {
+    for (final ArtifactSet cachedArtifact in _artifacts) {
       if (cachedArtifact is EngineCachedArtifact) {
         allAvailible &= await cachedArtifact.checkForArtifacts(engineVersion);
       }
@@ -496,7 +496,7 @@ abstract class CachedArtifact extends ArtifactSet {
 
   /// Clear any zip/gzip files downloaded.
   void _removeDownloadedFiles() {
-    for (File f in downloadedFiles) {
+    for (final File f in downloadedFiles) {
       try {
         f.deleteSync();
       } on FileSystemException catch (e) {
@@ -606,7 +606,7 @@ class FlutterWebSdk extends CachedArtifact {
     final Uri url = Uri.parse('${cache.storageBaseUrl}/flutter_infra/flutter/$version/$platformName.zip');
     await _downloadZipArchive('Downloading Web SDK...', url, location);
     // This is a temporary work-around for not being able to safely download into a shared directory.
-    for (FileSystemEntity entity in location.listSync(recursive: true)) {
+    for (final FileSystemEntity entity in location.listSync(recursive: true)) {
       if (entity is File) {
         final List<String> segments = globals.fs.path.split(entity.path);
         segments.remove('flutter_web_sdk');
@@ -643,21 +643,21 @@ abstract class EngineCachedArtifact extends CachedArtifact {
   @override
   bool isUpToDateInner() {
     final Directory pkgDir = cache.getCacheDir('pkg');
-    for (String pkgName in getPackageDirs()) {
+    for (final String pkgName in getPackageDirs()) {
       final String pkgPath = globals.fs.path.join(pkgDir.path, pkgName);
       if (!globals.fs.directory(pkgPath).existsSync()) {
         return false;
       }
     }
 
-    for (List<String> toolsDir in getBinaryDirs()) {
+    for (final List<String> toolsDir in getBinaryDirs()) {
       final Directory dir = globals.fs.directory(globals.fs.path.join(location.path, toolsDir[0]));
       if (!dir.existsSync()) {
         return false;
       }
     }
 
-    for (String licenseDir in getLicenseDirs()) {
+    for (final String licenseDir in getLicenseDirs()) {
       final File file = globals.fs.file(globals.fs.path.join(location.path, licenseDir, 'LICENSE'));
       if (!file.existsSync()) {
         return false;
@@ -671,11 +671,11 @@ abstract class EngineCachedArtifact extends CachedArtifact {
     final String url = '${cache.storageBaseUrl}/flutter_infra/flutter/$version/';
 
     final Directory pkgDir = cache.getCacheDir('pkg');
-    for (String pkgName in getPackageDirs()) {
+    for (final String pkgName in getPackageDirs()) {
       await _downloadZipArchive('Downloading package $pkgName...', Uri.parse(url + pkgName + '.zip'), pkgDir);
     }
 
-    for (List<String> toolsDir in getBinaryDirs()) {
+    for (final List<String> toolsDir in getBinaryDirs()) {
       final String cacheDir = toolsDir[0];
       final String urlPath = toolsDir[1];
       final Directory dir = globals.fs.directory(globals.fs.path.join(location.path, cacheDir));
@@ -684,7 +684,7 @@ abstract class EngineCachedArtifact extends CachedArtifact {
       _makeFilesExecutable(dir);
 
       const List<String> frameworkNames = <String>['Flutter', 'FlutterMacOS'];
-      for (String frameworkName in frameworkNames) {
+      for (final String frameworkName in frameworkNames) {
         final File frameworkZip = globals.fs.file(globals.fs.path.join(dir.path, '$frameworkName.framework.zip'));
         if (frameworkZip.existsSync()) {
           final Directory framework = globals.fs.directory(globals.fs.path.join(dir.path, '$frameworkName.framework'));
@@ -695,7 +695,7 @@ abstract class EngineCachedArtifact extends CachedArtifact {
     }
 
     final File licenseSource = cache.getLicenseFile();
-    for (String licenseDir in getLicenseDirs()) {
+    for (final String licenseDir in getLicenseDirs()) {
       final String licenseDestinationPath = globals.fs.path.join(location.path, licenseDir, 'LICENSE');
       await licenseSource.copy(licenseDestinationPath);
     }
@@ -706,7 +706,7 @@ abstract class EngineCachedArtifact extends CachedArtifact {
     final String url = '${cache.storageBaseUrl}/flutter_infra/flutter/$engineVersion/';
 
     bool exists = false;
-    for (String pkgName in getPackageDirs()) {
+    for (final String pkgName in getPackageDirs()) {
       exists = await _doesRemoteExist('Checking package $pkgName is available...',
           Uri.parse(url + pkgName + '.zip'));
       if (!exists) {
@@ -714,7 +714,7 @@ abstract class EngineCachedArtifact extends CachedArtifact {
       }
     }
 
-    for (List<String> toolsDir in getBinaryDirs()) {
+    for (final List<String> toolsDir in getBinaryDirs()) {
       final String cacheDir = toolsDir[0];
       final String urlPath = toolsDir[1];
       exists = await _doesRemoteExist('Checking $cacheDir tools are available...',
@@ -728,7 +728,7 @@ abstract class EngineCachedArtifact extends CachedArtifact {
 
   void _makeFilesExecutable(Directory dir) {
     os.chmod(dir, 'a+r,a+x');
-    for (FileSystemEntity entity in dir.listSync(recursive: true)) {
+    for (final FileSystemEntity entity in dir.listSync(recursive: true)) {
       if (entity is File) {
         final FileStat stat = entity.statSync();
         final bool isUserExecutable = ((stat.mode >> 6) & 0x1) == 1;
@@ -1000,7 +1000,7 @@ class GradleWrapper extends CachedArtifact {
     if (!globals.fs.directory(wrapperDir).existsSync()) {
       return false;
     }
-    for (String scriptName in _gradleScripts) {
+    for (final String scriptName in _gradleScripts) {
       final File scriptFile = globals.fs.file(globals.fs.path.join(wrapperDir.path, scriptName));
       if (!scriptFile.existsSync()) {
         return false;
@@ -1189,7 +1189,7 @@ class IosUsbArtifacts extends CachedArtifact {
     if (executables == null) {
       return true;
     }
-    for (String executable in executables) {
+    for (final String executable in executables) {
       if (!location.childFile(executable).existsSync()) {
         return false;
       }
diff --git a/packages/flutter_tools/lib/src/codegen.dart b/packages/flutter_tools/lib/src/codegen.dart
index 75e10727fe1..6be4fed1e73 100644
--- a/packages/flutter_tools/lib/src/codegen.dart
+++ b/packages/flutter_tools/lib/src/codegen.dart
@@ -118,7 +118,7 @@ class CodeGeneratingKernelCompiler implements KernelCompiler {
     codeGenerator.updatePackages(flutterProject);
     final CodegenDaemon codegenDaemon = await codeGenerator.daemon(flutterProject);
     codegenDaemon.startBuild();
-    await for (CodegenStatus codegenStatus in codegenDaemon.buildResults) {
+    await for (final CodegenStatus codegenStatus in codegenDaemon.buildResults) {
       if (codegenStatus == CodegenStatus.Failed) {
         globals.printError('Code generation failed, build may have compile errors.');
         break;
diff --git a/packages/flutter_tools/lib/src/commands/analyze_base.dart b/packages/flutter_tools/lib/src/commands/analyze_base.dart
index 568e1170d02..63fb3dce1d6 100644
--- a/packages/flutter_tools/lib/src/commands/analyze_base.dart
+++ b/packages/flutter_tools/lib/src/commands/analyze_base.dart
@@ -86,8 +86,8 @@ class PackageDependency {
   bool get hasConflict => values.length > 1;
   bool get hasConflictAffectingFlutterRepo {
     assert(globals.fs.path.isAbsolute(Cache.flutterRoot));
-    for (List<String> targetSources in values.values) {
-      for (String source in targetSources) {
+    for (final List<String> targetSources in values.values) {
+      for (final String source in targetSources) {
         assert(globals.fs.path.isAbsolute(source));
         if (globals.fs.path.isWithin(Cache.flutterRoot, source)) {
           return true;
@@ -100,11 +100,11 @@ class PackageDependency {
     assert(hasConflict);
     final List<String> targets = values.keys.toList();
     targets.sort((String a, String b) => values[b].length.compareTo(values[a].length));
-    for (String target in targets) {
+    for (final String target in targets) {
       final int count = values[target].length;
       result.writeln('  $count ${count == 1 ? 'source wants' : 'sources want'} "$target":');
       bool canonical = false;
-      for (String source in values[target]) {
+      for (final String source in values[target]) {
         result.writeln('    $source');
         if (source == canonicalSource) {
           canonical = true;
@@ -140,7 +140,7 @@ class PackageDependencyTracker {
         .readAsStringSync()
         .split('\n')
         .where((String line) => !line.startsWith(RegExp(r'^ *#')));
-      for (String line in lines) {
+      for (final String line in lines) {
         final int colon = line.indexOf(':');
         if (colon > 0) {
           final String packageName = line.substring(0, colon);
@@ -165,7 +165,7 @@ class PackageDependencyTracker {
   }
 
   void checkForConflictingDependencies(Iterable<Directory> pubSpecDirectories, PackageDependencyTracker dependencies) {
-    for (Directory directory in pubSpecDirectories) {
+    for (final Directory directory in pubSpecDirectories) {
       final String pubSpecYamlPath = globals.fs.path.join(directory.path, 'pubspec.yaml');
       final File pubSpecYamlFile = globals.fs.file(pubSpecYamlPath);
       if (pubSpecYamlFile.existsSync()) {
@@ -219,7 +219,7 @@ class PackageDependencyTracker {
   String generateConflictReport() {
     assert(hasConflicts);
     final StringBuffer result = StringBuffer();
-    for (String package in packages.keys.where((String package) => packages[package].hasConflict)) {
+    for (final String package in packages.keys.where((String package) => packages[package].hasConflict)) {
       result.writeln('Package "$package" has conflicts:');
       packages[package].describeConflict(result);
     }
@@ -228,7 +228,7 @@ class PackageDependencyTracker {
 
   Map<String, String> asPackageMap() {
     final Map<String, String> result = <String, String>{};
-    for (String package in packages.keys) {
+    for (final String package in packages.keys) {
       result[package] = packages[package].target;
     }
     return result;
diff --git a/packages/flutter_tools/lib/src/commands/analyze_continuously.dart b/packages/flutter_tools/lib/src/commands/analyze_continuously.dart
index 2e9802c316f..c6271d5dcb1 100644
--- a/packages/flutter_tools/lib/src/commands/analyze_continuously.dart
+++ b/packages/flutter_tools/lib/src/commands/analyze_continuously.dart
@@ -43,7 +43,7 @@ class AnalyzeContinuously extends AnalyzeBase {
       analysisTarget = 'Flutter repository';
 
       globals.printTrace('Analyzing Flutter repository:');
-      for (String projectPath in repoRoots) {
+      for (final String projectPath in repoRoots) {
         globals.printTrace('  ${globals.fs.path.relative(projectPath)}');
       }
     } else {
@@ -91,7 +91,7 @@ class AnalyzeContinuously extends AnalyzeBase {
 
       // Remove errors for deleted files, sort, and print errors.
       final List<AnalysisError> errors = <AnalysisError>[];
-      for (String path in analysisErrors.keys.toList()) {
+      for (final String path in analysisErrors.keys.toList()) {
         if (globals.fs.isFileSync(path)) {
           errors.addAll(analysisErrors[path]);
         } else {
@@ -112,7 +112,7 @@ class AnalyzeContinuously extends AnalyzeBase {
 
       errors.sort();
 
-      for (AnalysisError error in errors) {
+      for (final AnalysisError error in errors) {
         globals.printStatus(error.toString());
         if (error.code != null) {
           globals.printTrace('error code: ${error.code}');
diff --git a/packages/flutter_tools/lib/src/commands/analyze_once.dart b/packages/flutter_tools/lib/src/commands/analyze_once.dart
index aaa44dfdd41..db2b7245093 100644
--- a/packages/flutter_tools/lib/src/commands/analyze_once.dart
+++ b/packages/flutter_tools/lib/src/commands/analyze_once.dart
@@ -41,7 +41,7 @@ class AnalyzeOnce extends AnalyzeBase {
     final Set<String> directories = Set<String>.from(argResults.rest
         .map<String>((String path) => globals.fs.path.canonicalize(path)));
     if (directories.isNotEmpty) {
-      for (String directory in directories) {
+      for (final String directory in directories) {
         final FileSystemEntityType type = globals.fs.typeSync(directory);
 
         if (type == FileSystemEntityType.notFound) {
@@ -138,7 +138,7 @@ class AnalyzeOnce extends AnalyzeBase {
       globals.printStatus('');
     }
     errors.sort();
-    for (AnalysisError error in errors) {
+    for (final AnalysisError error in errors) {
       globals.printStatus(error.toString(), hangingIndent: 7);
     }
 
diff --git a/packages/flutter_tools/lib/src/commands/assemble.dart b/packages/flutter_tools/lib/src/commands/assemble.dart
index 583412b869d..75fc58d635a 100644
--- a/packages/flutter_tools/lib/src/commands/assemble.dart
+++ b/packages/flutter_tools/lib/src/commands/assemble.dart
@@ -115,11 +115,11 @@ class AssembleCommand extends FlutterCommand {
     }
     final String name = argResults.rest.first;
     final Map<String, Target> targetMap = <String, Target>{
-      for (Target target in _kDefaultTargets)
+      for (final Target target in _kDefaultTargets)
         target.name: target
     };
     final List<Target> results = <Target>[
-      for (String targetName in argResults.rest)
+      for (final String targetName in argResults.rest)
         if (targetMap.containsKey(targetName))
           targetMap[targetName]
     ];
@@ -153,7 +153,7 @@ class AssembleCommand extends FlutterCommand {
 
   Map<String, String> _parseDefines(List<String> values) {
     final Map<String, String> results = <String, String>{};
-    for (String chunk in values) {
+    for (final String chunk in values) {
       final int indexEquals = chunk.indexOf('=');
       if (indexEquals == -1) {
         throwToolExit('Improperly formatted define flag: $chunk');
@@ -179,7 +179,7 @@ class AssembleCommand extends FlutterCommand {
         : null,
     ));
     if (!result.success) {
-      for (ExceptionMeasurement measurement in result.exceptions.values) {
+      for (final ExceptionMeasurement measurement in result.exceptions.values) {
         globals.printError('Target ${measurement.target} failed: ${measurement.exception}',
           stackTrace: measurement.fatal
             ? measurement.stackTrace
@@ -209,7 +209,7 @@ void writeListIfChanged(List<File> files, String path) {
   final File file = globals.fs.file(path);
   final StringBuffer buffer = StringBuffer();
   // These files are already sorted.
-  for (File file in files) {
+  for (final File file in files) {
     buffer.writeln(file.path);
   }
   final String newContents = buffer.toString();
diff --git a/packages/flutter_tools/lib/src/commands/attach.dart b/packages/flutter_tools/lib/src/commands/attach.dart
index 3ce4a892276..421b425c000 100644
--- a/packages/flutter_tools/lib/src/commands/attach.dart
+++ b/packages/flutter_tools/lib/src/commands/attach.dart
@@ -226,7 +226,7 @@ class AttachCommand extends FlutterCommand {
         } catch (_) {
           isolateDiscoveryProtocol?.dispose();
           final List<ForwardedPort> ports = device.portForwarder.forwardedPorts.toList();
-          for (ForwardedPort port in ports) {
+          for (final ForwardedPort port in ports) {
             await device.portForwarder.unforward(port);
           }
           rethrow;
@@ -329,7 +329,7 @@ class AttachCommand extends FlutterCommand {
       }
     } finally {
       final List<ForwardedPort> ports = device.portForwarder.forwardedPorts.toList();
-      for (ForwardedPort port in ports) {
+      for (final ForwardedPort port in ports) {
         await device.portForwarder.unforward(port);
       }
     }
diff --git a/packages/flutter_tools/lib/src/commands/build_aar.dart b/packages/flutter_tools/lib/src/commands/build_aar.dart
index 84a83d8e90b..7b798c62d2a 100644
--- a/packages/flutter_tools/lib/src/commands/build_aar.dart
+++ b/packages/flutter_tools/lib/src/commands/build_aar.dart
@@ -101,7 +101,7 @@ class BuildAarCommand extends BuildSubCommand {
       ? stringArg('build-number')
       : '1.0';
 
-    for (String buildMode in const <String>['debug', 'profile', 'release']) {
+    for (final String buildMode in const <String>['debug', 'profile', 'release']) {
       if (boolArg(buildMode)) {
         androidBuildInfo.add(AndroidBuildInfo(
           BuildInfo(BuildMode.fromName(buildMode), stringArg('flavor')),
diff --git a/packages/flutter_tools/lib/src/commands/build_ios_framework.dart b/packages/flutter_tools/lib/src/commands/build_ios_framework.dart
index bd48a1297ef..3ac3b489fe9 100644
--- a/packages/flutter_tools/lib/src/commands/build_ios_framework.dart
+++ b/packages/flutter_tools/lib/src/commands/build_ios_framework.dart
@@ -158,7 +158,7 @@ class BuildIOSFrameworkCommand extends BuildSubCommand {
     bundleBuilder ??= BundleBuilder();
     cache ??= globals.cache;
 
-    for (BuildMode mode in buildModes) {
+    for (final BuildMode mode in buildModes) {
       globals.printStatus('Building framework for $iosProject in ${getNameForBuildMode(mode)} mode...');
       final String xcodeBuildConfiguration = toTitleCase(getNameForBuildMode(mode));
       final Directory modeDirectory = outputDirectory.childDirectory(xcodeBuildConfiguration);
@@ -470,8 +470,8 @@ end
       final Directory iPhoneBuildConfiguration = iPhoneBuildOutput.childDirectory('$xcodeBuildConfiguration-iphoneos');
       final Directory simulatorBuildConfiguration = simulatorBuildOutput.childDirectory('$xcodeBuildConfiguration-iphonesimulator');
 
-      for (Directory builtProduct in iPhoneBuildConfiguration.listSync(followLinks: false).whereType<Directory>()) {
-        for (FileSystemEntity podProduct in builtProduct.listSync(followLinks: false)) {
+      for (final Directory builtProduct in iPhoneBuildConfiguration.listSync(followLinks: false).whereType<Directory>()) {
+        for (final FileSystemEntity podProduct in builtProduct.listSync(followLinks: false)) {
           final String podFrameworkName = podProduct.basename;
           if (globals.fs.path.extension(podFrameworkName) == '.framework') {
             final String binaryName = globals.fs.path.basenameWithoutExtension(podFrameworkName);
diff --git a/packages/flutter_tools/lib/src/commands/clean.dart b/packages/flutter_tools/lib/src/commands/clean.dart
index 5d7bc070bc7..db78584f9e8 100644
--- a/packages/flutter_tools/lib/src/commands/clean.dart
+++ b/packages/flutter_tools/lib/src/commands/clean.dart
@@ -73,7 +73,7 @@ class CleanCommand extends FlutterCommand {
     try {
       final Directory xcodeWorkspace = xcodeProject.xcodeWorkspace;
       final XcodeProjectInfo projectInfo = await xcodeProjectInterpreter.getInfo(xcodeWorkspace.parent.path);
-      for (String scheme in projectInfo.schemes) {
+      for (final String scheme in projectInfo.schemes) {
         xcodeProjectInterpreter.cleanWorkspace(xcodeWorkspace.path, scheme);
       }
     } catch (error) {
diff --git a/packages/flutter_tools/lib/src/commands/config.dart b/packages/flutter_tools/lib/src/commands/config.dart
index d1626acc2bb..c4ab2c897cb 100644
--- a/packages/flutter_tools/lib/src/commands/config.dart
+++ b/packages/flutter_tools/lib/src/commands/config.dart
@@ -30,7 +30,7 @@ class ConfigCommand extends FlutterCommand {
       negatable: false,
       hide: !verboseHelp,
       help: 'Print config values as json.');
-    for (Feature feature in allFeatures) {
+    for (final Feature feature in allFeatures) {
       if (feature.configSetting == null) {
         continue;
       }
@@ -69,7 +69,7 @@ class ConfigCommand extends FlutterCommand {
     // are available.
     final Map<String, Feature> featuresByName = <String, Feature>{};
     final String channel = FlutterVersion.instance.channel;
-    for (Feature feature in allFeatures) {
+    for (final Feature feature in allFeatures) {
       if (feature.configSetting != null) {
         featuresByName[feature.configSetting] = feature;
       }
@@ -105,7 +105,7 @@ class ConfigCommand extends FlutterCommand {
     }
 
     if (boolArg('clear-features')) {
-      for (Feature feature in allFeatures) {
+      for (final Feature feature in allFeatures) {
         if (feature.configSetting != null) {
           globals.config.removeValue(feature.configSetting);
         }
@@ -140,7 +140,7 @@ class ConfigCommand extends FlutterCommand {
       _updateConfig('build-dir', buildDir);
     }
 
-    for (Feature feature in allFeatures) {
+    for (final Feature feature in allFeatures) {
       if (feature.configSetting == null) {
         continue;
       }
@@ -163,7 +163,7 @@ class ConfigCommand extends FlutterCommand {
   Future<void> handleMachine() async {
     // Get all the current values.
     final Map<String, dynamic> results = <String, dynamic>{};
-    for (String key in globals.config.keys) {
+    for (final String key in globals.config.keys) {
       results[key] = globals.config.getValue(key);
     }
 
diff --git a/packages/flutter_tools/lib/src/commands/create.dart b/packages/flutter_tools/lib/src/commands/create.dart
index 823da6acefa..3de6c2b8444 100644
--- a/packages/flutter_tools/lib/src/commands/create.dart
+++ b/packages/flutter_tools/lib/src/commands/create.dart
@@ -44,7 +44,7 @@ enum _ProjectType {
 
 _ProjectType _stringToProjectType(String value) {
   _ProjectType result;
-  for (_ProjectType type in _ProjectType.values) {
+  for (final _ProjectType type in _ProjectType.values) {
     if (value == getEnumName(type)) {
       result = type;
       break;
@@ -306,7 +306,7 @@ class CreateCommand extends FlutterCommand {
 
     if (argResults.rest.length > 1) {
       String message = 'Multiple output directories specified.';
-      for (String arg in argResults.rest) {
+      for (final String arg in argResults.rest) {
         if (arg.startsWith('-')) {
           message += '\nTry moving $arg to be immediately following $name';
           break;
diff --git a/packages/flutter_tools/lib/src/commands/daemon.dart b/packages/flutter_tools/lib/src/commands/daemon.dart
index 0c30d603033..1b7cf438918 100644
--- a/packages/flutter_tools/lib/src/commands/daemon.dart
+++ b/packages/flutter_tools/lib/src/commands/daemon.dart
@@ -204,7 +204,7 @@ class Daemon {
 
   void shutdown({ dynamic error }) {
     _commandSubscription?.cancel();
-    for (Domain domain in _domainMap.values) {
+    for (final Domain domain in _domainMap.values) {
       domain.dispose();
     }
     if (!_onExitCompleter.isCompleted) {
@@ -791,15 +791,15 @@ class DeviceDomain extends Domain {
   /// of properties (id, name, platform, ...).
   Future<List<Map<String, dynamic>>> getDevices([ Map<String, dynamic> args ]) async {
     return <Map<String, dynamic>>[
-      for (PollingDeviceDiscovery discoverer in _discoverers)
-        for (Device device in await discoverer.devices)
+      for (final PollingDeviceDiscovery discoverer in _discoverers)
+        for (final Device device in await discoverer.devices)
           await _deviceToMap(device),
     ];
   }
 
   /// Enable device events.
   Future<void> enable(Map<String, dynamic> args) {
-    for (PollingDeviceDiscovery discoverer in _discoverers) {
+    for (final PollingDeviceDiscovery discoverer in _discoverers) {
       discoverer.startPolling();
     }
     return Future<void>.value();
@@ -807,7 +807,7 @@ class DeviceDomain extends Domain {
 
   /// Disable device events.
   Future<void> disable(Map<String, dynamic> args) {
-    for (PollingDeviceDiscovery discoverer in _discoverers) {
+    for (final PollingDeviceDiscovery discoverer in _discoverers) {
       discoverer.stopPolling();
     }
     return Future<void>.value();
@@ -845,14 +845,14 @@ class DeviceDomain extends Domain {
 
   @override
   void dispose() {
-    for (PollingDeviceDiscovery discoverer in _discoverers) {
+    for (final PollingDeviceDiscovery discoverer in _discoverers) {
       discoverer.dispose();
     }
   }
 
   /// Return the device matching the deviceId field in the args.
   Future<Device> _getDevice(String deviceId) async {
-    for (PollingDeviceDiscovery discoverer in _discoverers) {
+    for (final PollingDeviceDiscovery discoverer in _discoverers) {
       final Device device = (await discoverer.devices).firstWhere((Device device) => device.id == deviceId, orElse: () => null);
       if (device != null) {
         return device;
diff --git a/packages/flutter_tools/lib/src/commands/devices.dart b/packages/flutter_tools/lib/src/commands/devices.dart
index dbae6671c9f..5b478e94a04 100644
--- a/packages/flutter_tools/lib/src/commands/devices.dart
+++ b/packages/flutter_tools/lib/src/commands/devices.dart
@@ -38,7 +38,7 @@ class DevicesCommand extends FlutterCommand {
       final List<String> diagnostics = await deviceManager.getDeviceDiagnostics();
       if (diagnostics.isNotEmpty) {
         globals.printStatus('');
-        for (String diagnostic in diagnostics) {
+        for (final String diagnostic in diagnostics) {
           globals.printStatus('• $diagnostic', hangingIndent: 2);
         }
       }
diff --git a/packages/flutter_tools/lib/src/commands/generate.dart b/packages/flutter_tools/lib/src/commands/generate.dart
index 7b23bae532b..6d58beacf7c 100644
--- a/packages/flutter_tools/lib/src/commands/generate.dart
+++ b/packages/flutter_tools/lib/src/commands/generate.dart
@@ -26,7 +26,7 @@ class GenerateCommand extends FlutterCommand {
     final FlutterProject flutterProject = FlutterProject.current();
     final CodegenDaemon codegenDaemon = await codeGenerator.daemon(flutterProject);
     codegenDaemon.startBuild();
-    await for (CodegenStatus codegenStatus in codegenDaemon.buildResults) {
+    await for (final CodegenStatus codegenStatus in codegenDaemon.buildResults) {
       if (codegenStatus == CodegenStatus.Failed) {
         globals.printError('Code generation failed.');
         break;
@@ -44,7 +44,7 @@ class GenerateCommand extends FlutterCommand {
       return null;
     }
     final Directory errorCache = errorCacheParent.childDirectory('error_cache');
-    for (File errorFile in errorCache.listSync(recursive: true).whereType<File>()) {
+    for (final File errorFile in errorCache.listSync(recursive: true).whereType<File>()) {
       try {
         final List<Object> errorData = json.decode(errorFile.readAsStringSync()) as List<Object>;
         final List<Object> stackData = errorData[1] as List<Object>;
diff --git a/packages/flutter_tools/lib/src/commands/ide_config.dart b/packages/flutter_tools/lib/src/commands/ide_config.dart
index fd1c6fcae6a..f42899abca9 100644
--- a/packages/flutter_tools/lib/src/commands/ide_config.dart
+++ b/packages/flutter_tools/lib/src/commands/ide_config.dart
@@ -126,7 +126,7 @@ class IdeConfigCommand extends FlutterCommand {
 
     final Set<String> manifest = <String>{};
     final Iterable<File> flutterFiles = _flutterRoot.listSync(recursive: true).whereType<File>();
-    for (File srcFile in flutterFiles) {
+    for (final File srcFile in flutterFiles) {
       final String relativePath = globals.fs.path.relative(srcFile.path, from: _flutterRoot.absolute.path);
 
       // Skip template files in both the ide_templates and templates
@@ -186,7 +186,7 @@ class IdeConfigCommand extends FlutterCommand {
     // Look for any files under the template dir that don't exist in the manifest and remove
     // them.
     final Iterable<File> templateFiles = _templateDirectory.listSync(recursive: true).whereType<File>();
-    for (File templateFile in templateFiles) {
+    for (final File templateFile in templateFiles) {
       final String relativePath = globals.fs.path.relative(
         templateFile.absolute.path,
         from: _templateDirectory.absolute.path,
diff --git a/packages/flutter_tools/lib/src/commands/precache.dart b/packages/flutter_tools/lib/src/commands/precache.dart
index d9a6dd20a69..10b0316b6e5 100644
--- a/packages/flutter_tools/lib/src/commands/precache.dart
+++ b/packages/flutter_tools/lib/src/commands/precache.dart
@@ -66,7 +66,7 @@ class PrecacheCommand extends FlutterCommand {
       globals.cache.useUnsignedMacBinaries = true;
     }
     final Set<DevelopmentArtifact> requiredArtifacts = <DevelopmentArtifact>{};
-    for (DevelopmentArtifact artifact in DevelopmentArtifact.values) {
+    for (final DevelopmentArtifact artifact in DevelopmentArtifact.values) {
       // Don't include unstable artifacts on stable branches.
       if (!FlutterVersion.instance.isMaster && artifact.unstable) {
         continue;
diff --git a/packages/flutter_tools/lib/src/commands/run.dart b/packages/flutter_tools/lib/src/commands/run.dart
index 0fe5581f57c..e42857901da 100644
--- a/packages/flutter_tools/lib/src/commands/run.dart
+++ b/packages/flutter_tools/lib/src/commands/run.dart
@@ -245,7 +245,7 @@ class RunCommand extends RunCommandBase {
       deviceType = 'multiple';
       deviceOsVersion = 'multiple';
       isEmulator = false;
-      for (Device device in devices) {
+      for (final Device device in devices) {
         final TargetPlatform platform = await device.targetPlatform;
         anyAndroidDevices = anyAndroidDevices || (platform == TargetPlatform.android);
         anyIOSDevices = anyIOSDevices || (platform == TargetPlatform.ios);
@@ -426,7 +426,7 @@ class RunCommand extends RunCommandBase {
                            'channel.', null);
     }
 
-    for (Device device in devices) {
+    for (final Device device in devices) {
       if (!device.supportsFastStart && boolArg('fast-start')) {
         globals.printStatus(
           'Using --fast-start option with device ${device.name}, but this device '
@@ -456,7 +456,7 @@ class RunCommand extends RunCommandBase {
     }
 
     if (hotMode) {
-      for (Device device in devices) {
+      for (final Device device in devices) {
         if (!device.supportsHotReload) {
           throwToolExit('Hot reload is not supported by ${device.name}. Run with --no-hot.');
         }
@@ -470,7 +470,7 @@ class RunCommand extends RunCommandBase {
     }
     final FlutterProject flutterProject = FlutterProject.current();
     final List<FlutterDevice> flutterDevices = <FlutterDevice>[
-      for (Device device in devices)
+      for (final Device device in devices)
         await FlutterDevice.create(
           device,
           flutterProject: flutterProject,
diff --git a/packages/flutter_tools/lib/src/commands/test.dart b/packages/flutter_tools/lib/src/commands/test.dart
index 21e2e0fbc05..efdaecc38ed 100644
--- a/packages/flutter_tools/lib/src/commands/test.dart
+++ b/packages/flutter_tools/lib/src/commands/test.dart
@@ -222,7 +222,7 @@ class TestCommand extends FastFlutterCommand {
     if (flutterProject.hasBuilders) {
       final CodegenDaemon codegenDaemon = await codeGenerator.daemon(flutterProject);
       codegenDaemon.startBuild();
-      await for (CodegenStatus status in codegenDaemon.buildResults) {
+      await for (final CodegenStatus status in codegenDaemon.buildResults) {
         if (status == CodegenStatus.Succeeded) {
           break;
         }
@@ -296,7 +296,7 @@ class TestCommand extends FastFlutterCommand {
       return true;
     }
 
-    for (DevFSFileContent entry in entries.values.whereType<DevFSFileContent>()) {
+    for (final DevFSFileContent entry in entries.values.whereType<DevFSFileContent>()) {
       // Calling isModified to access file stats first in order for isModifiedAfter
       // to work.
       if (entry.isModified && entry.isModifiedAfter(lastModified)) {
diff --git a/packages/flutter_tools/lib/src/commands/update_packages.dart b/packages/flutter_tools/lib/src/commands/update_packages.dart
index 169e276079b..b892a4f5e37 100644
--- a/packages/flutter_tools/lib/src/commands/update_packages.dart
+++ b/packages/flutter_tools/lib/src/commands/update_packages.dart
@@ -134,7 +134,7 @@ class UpdatePackagesCommand extends FlutterCommand {
     if (isVerifyOnly) {
       bool needsUpdate = false;
       globals.printStatus('Verifying pubspecs...');
-      for (Directory directory in packages) {
+      for (final Directory directory in packages) {
         PubspecYaml pubspec;
         try {
           pubspec = PubspecYaml(directory);
@@ -153,7 +153,7 @@ class UpdatePackagesCommand extends FlutterCommand {
         }
         // all dependencies in the pubspec sorted lexically.
         final Map<String, String> checksumDependencies = <String, String>{};
-        for (PubspecLine data in pubspec.inputData) {
+        for (final PubspecLine data in pubspec.inputData) {
           if (data is PubspecDependency && data.kind == DependencyKind.normal) {
             checksumDependencies[data.name] = data.version;
           }
@@ -194,7 +194,7 @@ class UpdatePackagesCommand extends FlutterCommand {
       final List<PubspecYaml> pubspecs = <PubspecYaml>[];
       final Map<String, PubspecDependency> dependencies = <String, PubspecDependency>{};
       final Set<String> specialDependencies = <String>{};
-      for (Directory directory in packages) { // these are all the directories with pubspec.yamls we care about
+      for (final Directory directory in packages) { // these are all the directories with pubspec.yamls we care about
         globals.printTrace('Reading pubspec.yaml from: ${directory.path}');
         PubspecYaml pubspec;
         try {
@@ -203,7 +203,7 @@ class UpdatePackagesCommand extends FlutterCommand {
           throwToolExit(message);
         }
         pubspecs.add(pubspec); // remember it for later
-        for (PubspecDependency dependency in pubspec.allDependencies) { // this is all the explicit dependencies
+        for (final PubspecDependency dependency in pubspec.allDependencies) { // this is all the explicit dependencies
           if (dependencies.containsKey(dependency.name)) {
             // If we've seen the dependency before, make sure that we are
             // importing it the same way. There's several ways to import a
@@ -272,13 +272,13 @@ class UpdatePackagesCommand extends FlutterCommand {
       // The transitive dependency tree for the fake package does not contain
       // dependencies between Flutter SDK packages and pub packages. We add them
       // here.
-      for (PubspecYaml pubspec in pubspecs) {
+      for (final PubspecYaml pubspec in pubspecs) {
         final String package = pubspec.name;
         specialDependencies.add(package);
         tree._versions[package] = pubspec.version;
         assert(!tree._dependencyTree.containsKey(package));
         tree._dependencyTree[package] = <String>{};
-        for (PubspecDependency dependency in pubspec.dependencies) {
+        for (final PubspecDependency dependency in pubspec.dependencies) {
           if (dependency.kind == DependencyKind.normal) {
             tree._dependencyTree[package].add(dependency.name);
           }
@@ -305,7 +305,7 @@ class UpdatePackagesCommand extends FlutterCommand {
       // to specific versions because they are explicitly pinned by their
       // constraints. Here we list the names we earlier established we didn't
       // need to pin because they come from the Dart or Flutter SDKs.
-      for (PubspecYaml pubspec in pubspecs) {
+      for (final PubspecYaml pubspec in pubspecs) {
         pubspec.apply(tree, specialDependencies);
       }
 
@@ -318,7 +318,7 @@ class UpdatePackagesCommand extends FlutterCommand {
     final Stopwatch timer = Stopwatch()..start();
     int count = 0;
 
-    for (Directory dir in packages) {
+    for (final Directory dir in packages) {
       await pub.get(context: PubContext.updatePackages, directory: dir.path, checkLastModified: false);
       count += 1;
     }
@@ -356,7 +356,7 @@ class UpdatePackagesCommand extends FlutterCommand {
       if (link.from != null) {
         visited.add(link.from.to);
       }
-      for (String dependency in tree._dependencyTree[link.to]) {
+      for (final String dependency in tree._dependencyTree[link.to]) {
         if (!visited.contains(dependency)) {
           traversalQueue.addFirst(_DependencyLink(from: link, to: dependency));
         }
@@ -483,7 +483,7 @@ class PubspecYaml {
     // the dependency. So we track what is the "current" (or "last") dependency
     // that we are dealing with using this variable.
     PubspecDependency lastDependency;
-    for (String line in lines) {
+    for (final String line in lines) {
       if (lastDependency == null) {
         // First we look to see if we're transitioning to a new top-level section.
         // The PubspecHeader.parse static method can recognize those headers.
@@ -614,7 +614,7 @@ class PubspecYaml {
     // overridden by subsequent entries in the same file and any that have the
     // magic comment flagging them as auto-generated transitive dependencies
     // that we added in a previous run.
-    for (PubspecLine data in inputData) {
+    for (final PubspecLine data in inputData) {
       if (data is PubspecDependency && data.kind != DependencyKind.overridden && !data.isTransitive && !data.isDevDependency) {
         yield data;
       }
@@ -623,7 +623,7 @@ class PubspecYaml {
 
   /// This returns all regular dependencies and all dev dependencies.
   Iterable<PubspecDependency> get allDependencies sync* {
-    for (PubspecLine data in inputData) {
+    for (final PubspecLine data in inputData) {
       if (data is PubspecDependency && data.kind != DependencyKind.overridden && !data.isTransitive) {
         yield data;
       }
@@ -652,7 +652,7 @@ class PubspecYaml {
     // blank lines, and trailing blank lines, and ensuring the file ends with a
     // newline. This cleanup lets us be a little more aggressive while building
     // the output.
-    for (PubspecLine data in inputData) {
+    for (final PubspecLine data in inputData) {
       if (data is PubspecHeader) {
         // This line was a header of some sort.
         //
@@ -754,10 +754,10 @@ class PubspecYaml {
     // Create a new set to hold the list of packages we've already processed, so
     // that we don't redundantly process them multiple times.
     final Set<String> done = <String>{};
-    for (String package in directDependencies) {
+    for (final String package in directDependencies) {
       transitiveDependencies.addAll(versions.getTransitiveDependenciesFor(package, seen: done, exclude: implied));
     }
-    for (String package in devDependencies) {
+    for (final String package in devDependencies) {
       transitiveDevDependencies.addAll(versions.getTransitiveDependenciesFor(package, seen: done, exclude: implied));
     }
 
@@ -770,10 +770,10 @@ class PubspecYaml {
     }
 
     // Add a line for each transitive dependency and transitive dev dependency using our magic string to recognize them later.
-    for (String package in transitiveDependenciesAsList) {
+    for (final String package in transitiveDependenciesAsList) {
       transitiveDependencyOutput.add(computeTransitiveDependencyLineFor(package));
     }
-    for (String package in transitiveDevDependenciesAsList) {
+    for (final String package in transitiveDevDependenciesAsList) {
       transitiveDevDependencyOutput.add(computeTransitiveDependencyLineFor(package));
     }
 
@@ -1148,10 +1148,10 @@ String _generateFakePubspec(Iterable<PubspecDependency> dependencies) {
   if (_kManuallyPinnedDependencies.isNotEmpty) {
     globals.printStatus('WARNING: the following packages use hard-coded version constraints:');
     final Set<String> allTransitive = <String>{
-      for (PubspecDependency dependency in dependencies)
+      for (final PubspecDependency dependency in dependencies)
         dependency.name,
     };
-    for (String package in _kManuallyPinnedDependencies.keys) {
+    for (final String package in _kManuallyPinnedDependencies.keys) {
       // Don't add pinned dependency if it is not in the set of all transitive dependencies.
       if (!allTransitive.contains(package)) {
         globals.printStatus('Skipping $package because it was not transitive');
@@ -1162,7 +1162,7 @@ String _generateFakePubspec(Iterable<PubspecDependency> dependencies) {
       globals.printStatus('  - $package: $version');
     }
   }
-  for (PubspecDependency dependency in dependencies) {
+  for (final PubspecDependency dependency in dependencies) {
     if (!dependency.pointsToSdk) {
       dependency.describeForFakePubspec(result, overrides);
     }
@@ -1256,7 +1256,7 @@ class PubDependencyTree {
       // because they were omitted from pubspec.yaml used for 'pub upgrade' run.
       return;
     }
-    for (String dependency in _dependencyTree[package]) {
+    for (final String dependency in _dependencyTree[package]) {
       if (!seen.contains(dependency)) {
         if (!exclude.contains(dependency)) {
           yield dependency;
@@ -1279,7 +1279,7 @@ String _computeChecksum(Iterable<String> names, String getVersion(String name))
   int lowerCheck = 0;
   int upperCheck = 0;
   final List<String> sortedNames = names.toList()..sort();
-  for (String name in sortedNames) {
+  for (final String name in sortedNames) {
     final String version = getVersion(name);
     assert(version != '');
     if (version == null) {
@@ -1287,7 +1287,7 @@ String _computeChecksum(Iterable<String> names, String getVersion(String name))
     }
     final String value = '$name: $version';
     // Each code unit is 16 bits.
-    for (int codeUnit in value.codeUnits) {
+    for (final int codeUnit in value.codeUnits) {
       final int upper = codeUnit >> 8;
       final int lower = codeUnit & 0xFF;
       lowerCheck = (lowerCheck + upper) % 255;
diff --git a/packages/flutter_tools/lib/src/compile.dart b/packages/flutter_tools/lib/src/compile.dart
index 30a03bbf6b5..af7ce54acdf 100644
--- a/packages/flutter_tools/lib/src/compile.dart
+++ b/packages/flutter_tools/lib/src/compile.dart
@@ -198,7 +198,7 @@ class PackageUriMapper {
   PackageUriMapper(String scriptPath, String packagesPath, String fileSystemScheme, List<String> fileSystemRoots) {
     final Map<String, Uri> packageMap = PackageMap(globals.fs.path.absolute(packagesPath)).map;
     final String scriptUri = Uri.file(scriptPath, windows: globals.platform.isWindows).toString();
-    for (String packageName in packageMap.keys) {
+    for (final String packageName in packageMap.keys) {
       final String prefix = packageMap[packageName].toString();
       // Only perform a multi-root mapping if there are multiple roots.
       if (fileSystemScheme != null
@@ -227,7 +227,7 @@ class PackageUriMapper {
       return null;
     }
     final String scriptUri = Uri.file(scriptPath, windows: globals.platform.isWindows).toString();
-    for (String uriPrefix in _uriPrefixes) {
+    for (final String uriPrefix in _uriPrefixes) {
       if (scriptUri.startsWith(uriPrefix)) {
         return Uri.parse('package:$_packageName/${scriptUri.substring(uriPrefix.length)}');
       }
@@ -314,7 +314,7 @@ class KernelCompiler {
       sdkRoot,
       '--target=$targetModel',
       '-Ddart.developer.causal_async_stacks=$causalAsyncStacks',
-      for (Object dartDefine in dartDefines)
+      for (final Object dartDefine in dartDefines)
         '-D$dartDefine',
       ..._buildModeOptions(buildMode),
       if (trackWidgetCreation) '--track-widget-creation',
@@ -336,7 +336,7 @@ class KernelCompiler {
         depFilePath,
       ],
       if (fileSystemRoots != null)
-        for (String root in fileSystemRoots) ...<String>[
+        for (final String root in fileSystemRoots) ...<String>[
           '--filesystem-root',
           root,
         ],
@@ -608,7 +608,7 @@ class DefaultResidentCompiler implements ResidentCompiler {
         : '';
     _server.stdin.writeln('recompile $mainUri$inputKey');
     globals.printTrace('<- recompile $mainUri$inputKey');
-    for (Uri fileUri in request.invalidatedFiles) {
+    for (final Uri fileUri in request.invalidatedFiles) {
       _server.stdin.writeln(_mapFileUri(fileUri.toString(), packageUriMapper));
       globals.printTrace('${_mapFileUri(fileUri.toString(), packageUriMapper)}');
     }
@@ -651,7 +651,7 @@ class DefaultResidentCompiler implements ResidentCompiler {
       '--incremental',
       '--target=$targetModel',
       '-Ddart.developer.causal_async_stacks=$causalAsyncStacks',
-      for (Object dartDefine in dartDefines)
+      for (final Object dartDefine in dartDefines)
         '-D$dartDefine',
       if (outputPath != null) ...<String>[
         '--output-dill',
@@ -667,7 +667,7 @@ class DefaultResidentCompiler implements ResidentCompiler {
       ..._buildModeOptions(buildMode),
       if (trackWidgetCreation) '--track-widget-creation',
       if (fileSystemRoots != null)
-        for (String root in fileSystemRoots) ...<String>[
+        for (final String root in fileSystemRoots) ...<String>[
           '--filesystem-root',
           root,
         ],
@@ -824,7 +824,7 @@ class DefaultResidentCompiler implements ResidentCompiler {
     }
 
     if (fileSystemRoots != null) {
-      for (String root in fileSystemRoots) {
+      for (final String root in fileSystemRoots) {
         if (filename.startsWith(root)) {
           return Uri(
               scheme: fileSystemScheme, path: filename.substring(root.length))
diff --git a/packages/flutter_tools/lib/src/dart/pub.dart b/packages/flutter_tools/lib/src/dart/pub.dart
index 375fdd38fa1..a2a5c4e6361 100644
--- a/packages/flutter_tools/lib/src/dart/pub.dart
+++ b/packages/flutter_tools/lib/src/dart/pub.dart
@@ -29,7 +29,7 @@ Pub get pub => context.get<Pub>();
 // We have server-side tooling that assumes the values are consistent.
 class PubContext {
   PubContext._(this._values) {
-    for (String item in _values) {
+    for (final String item in _values) {
       if (!_validContext.hasMatch(item)) {
         throw ArgumentError.value(
             _values, 'value', 'Must match RegExp ${_validContext.pattern}');
diff --git a/packages/flutter_tools/lib/src/desktop_device.dart b/packages/flutter_tools/lib/src/desktop_device.dart
index 0922824a4c1..65a2339001a 100644
--- a/packages/flutter_tools/lib/src/desktop_device.dart
+++ b/packages/flutter_tools/lib/src/desktop_device.dart
@@ -130,7 +130,7 @@ abstract class DesktopDevice extends Device {
     bool succeeded = true;
     // Walk a copy of _runningProcesses, since the exit handler removes from the
     // set.
-    for (Process process in Set<Process>.from(_runningProcesses)) {
+    for (final Process process in Set<Process>.from(_runningProcesses)) {
       succeeded &= process.kill();
     }
     return succeeded;
diff --git a/packages/flutter_tools/lib/src/device.dart b/packages/flutter_tools/lib/src/device.dart
index d7ac1514be4..9109845151a 100644
--- a/packages/flutter_tools/lib/src/device.dart
+++ b/packages/flutter_tools/lib/src/device.dart
@@ -118,7 +118,7 @@ class DeviceManager {
     }
 
     // Match on a id or name starting with [deviceId].
-    for (Device device in devices.where(startsWithDeviceId)) {
+    for (final Device device in devices.where(startsWithDeviceId)) {
       yield device;
     }
   }
@@ -136,8 +136,8 @@ class DeviceManager {
 
   /// Return the list of all connected devices.
   Stream<Device> getAllConnectedDevices() async* {
-    for (DeviceDiscovery discoverer in _platformDiscoverers) {
-      for (Device device in await discoverer.devices) {
+    for (final DeviceDiscovery discoverer in _platformDiscoverers) {
+      for (final Device device in await discoverer.devices) {
         yield device;
       }
     }
@@ -151,7 +151,7 @@ class DeviceManager {
   /// Get diagnostics about issues with any connected devices.
   Future<List<String>> getDeviceDiagnostics() async {
     return <String>[
-      for (DeviceDiscovery discoverer in _platformDiscoverers)
+      for (final DeviceDiscovery discoverer in _platformDiscoverers)
         ...await discoverer.getDiagnostics(),
     ];
   }
@@ -178,7 +178,7 @@ class DeviceManager {
     // compilers, and web requires an entirely different resident runner.
     if (hasSpecifiedAllDevices) {
       devices = <Device>[
-        for (Device device in devices)
+        for (final Device device in devices)
           if (await device.targetPlatform != TargetPlatform.fuchsia_arm64 &&
               await device.targetPlatform != TargetPlatform.fuchsia_x64 &&
               await device.targetPlatform != TargetPlatform.web_javascript)
@@ -191,7 +191,7 @@ class DeviceManager {
     // 'android' folder then don't attempt to launch with an Android device.
     if (devices.length > 1 && !hasSpecifiedDeviceId) {
       devices = <Device>[
-        for (Device device in devices)
+        for (final Device device in devices)
           if (isDeviceSupportedForProject(device, flutterProject))
             device,
       ];
@@ -460,7 +460,7 @@ abstract class Device {
 
     // Extract device information
     final List<List<String>> table = <List<String>>[];
-    for (Device device in devices) {
+    for (final Device device in devices) {
       String supportIndicator = device.isSupported() ? '' : ' (unsupported)';
       final TargetPlatform targetPlatform = await device.targetPlatform;
       if (await device.isLocalEmulator) {
@@ -478,12 +478,12 @@ abstract class Device {
     // Calculate column widths
     final List<int> indices = List<int>.generate(table[0].length - 1, (int i) => i);
     List<int> widths = indices.map<int>((int i) => 0).toList();
-    for (List<String> row in table) {
+    for (final List<String> row in table) {
       widths = indices.map<int>((int i) => math.max(widths[i], row[i].length)).toList();
     }
 
     // Join columns into lines of text
-    for (List<String> row in table) {
+    for (final List<String> row in table) {
       yield indices.map<String>((int i) => row[i].padRight(widths[i])).join(' • ') + ' • ${row.last}';
     }
   }
diff --git a/packages/flutter_tools/lib/src/doctor.dart b/packages/flutter_tools/lib/src/doctor.dart
index ccaf6902165..366e2f1b885 100644
--- a/packages/flutter_tools/lib/src/doctor.dart
+++ b/packages/flutter_tools/lib/src/doctor.dart
@@ -147,7 +147,7 @@ class Doctor {
   /// Return a list of [ValidatorTask] objects and starts validation on all
   /// objects in [validators].
   List<ValidatorTask> startValidatorTasks() => <ValidatorTask>[
-    for (DoctorValidator validator in validators)
+    for (final DoctorValidator validator in validators)
       ValidatorTask(
         validator,
         // We use an asyncGuard() here to be absolutely certain that
@@ -178,7 +178,7 @@ class Doctor {
     bool missingComponent = false;
     bool sawACrash = false;
 
-    for (DoctorValidator validator in validators) {
+    for (final DoctorValidator validator in validators) {
       final StringBuffer lineBuffer = StringBuffer();
       ValidationResult result;
       try {
@@ -248,7 +248,7 @@ class Doctor {
     bool doctorResult = true;
     int issues = 0;
 
-    for (ValidatorTask validatorTask in startValidatorTasks()) {
+    for (final ValidatorTask validatorTask in startValidatorTasks()) {
       final DoctorValidator validator = validatorTask.validator;
       final Status status = Status.withSpinner(
         timeout: timeoutConfiguration.fastOperation,
@@ -291,12 +291,12 @@ class Doctor {
             hangingIndent: result.leadingBox.length + 1);
       }
 
-      for (ValidationMessage message in result.messages) {
+      for (final ValidationMessage message in result.messages) {
         if (message.type != ValidationMessageType.information || verbose == true) {
           int hangingIndent = 2;
           int indent = 4;
           final String indicator = showColor ? message.coloredIndicator : message.indicator;
-          for (String line in '$indicator ${message.message}'.split('\n')) {
+          for (final String line in '$indicator ${message.message}'.split('\n')) {
             globals.printStatus(line, hangingIndent: hangingIndent, indent: indent, emphasis: true);
             // Only do hanging indent for the first line.
             hangingIndent = 0;
@@ -402,7 +402,7 @@ class GroupedValidator extends DoctorValidator {
   @override
   Future<ValidationResult> validate() async {
     final List<ValidatorTask> tasks = <ValidatorTask>[
-      for (DoctorValidator validator in subValidators)
+      for (final DoctorValidator validator in subValidators)
         ValidatorTask(
           validator,
           asyncGuard<ValidationResult>(() => validator.validate()),
@@ -410,7 +410,7 @@ class GroupedValidator extends DoctorValidator {
     ];
 
     final List<ValidationResult> results = <ValidationResult>[];
-    for (ValidatorTask subValidator in tasks) {
+    for (final ValidatorTask subValidator in tasks) {
       _currentSlowWarning = subValidator.validator.slowWarning;
       try {
         results.add(await subValidator.result);
@@ -429,7 +429,7 @@ class GroupedValidator extends DoctorValidator {
     final List<ValidationMessage> mergedMessages = <ValidationMessage>[];
     String statusInfo;
 
-    for (ValidationResult result in results) {
+    for (final ValidationResult result in results) {
       statusInfo ??= result.statusInfo;
       switch (result.type) {
         case ValidationType.installed:
@@ -753,7 +753,7 @@ class IntelliJValidatorOnLinuxAndWindows extends IntelliJValidator {
       validators.add(validator);
     }
 
-    for (FileSystemEntity dir in globals.fs.directory(homeDirPath).listSync()) {
+    for (final FileSystemEntity dir in globals.fs.directory(homeDirPath).listSync()) {
       if (dir is Directory) {
         final String name = globals.fs.path.basename(dir.path);
         IntelliJValidator._idToTitle.forEach((String id, String title) {
@@ -808,10 +808,10 @@ class IntelliJValidatorOnMac extends IntelliJValidator {
               .map<List<FileSystemEntity>>((Directory dir) => dir.existsSync() ? dir.listSync() : <FileSystemEntity>[])
               .expand<FileSystemEntity>((List<FileSystemEntity> mappedDirs) => mappedDirs)
               .whereType<Directory>();
-      for (Directory dir in installDirs) {
+      for (final Directory dir in installDirs) {
         checkForIntelliJ(dir);
         if (!dir.path.endsWith('.app')) {
-          for (FileSystemEntity subdir in dir.listSync()) {
+          for (final FileSystemEntity subdir in dir.listSync()) {
             if (subdir is Directory) {
               checkForIntelliJ(subdir);
             }
diff --git a/packages/flutter_tools/lib/src/emulator.dart b/packages/flutter_tools/lib/src/emulator.dart
index d29f2812aea..3cfcac6048b 100644
--- a/packages/flutter_tools/lib/src/emulator.dart
+++ b/packages/flutter_tools/lib/src/emulator.dart
@@ -250,7 +250,7 @@ abstract class Emulator {
 
     // Extract emulators information
     final List<List<String>> table = <List<String>>[
-      for (Emulator emulator in emulators)
+      for (final Emulator emulator in emulators)
         <String>[
           emulator.id ?? '',
           emulator.name ?? '',
@@ -262,7 +262,7 @@ abstract class Emulator {
     // Calculate column widths
     final List<int> indices = List<int>.generate(table[0].length - 1, (int i) => i);
     List<int> widths = indices.map<int>((int i) => 0).toList();
-    for (List<String> row in table) {
+    for (final List<String> row in table) {
       widths = indices.map<int>((int i) => math.max(widths[i], row[i].length)).toList();
     }
 
diff --git a/packages/flutter_tools/lib/src/flutter_manifest.dart b/packages/flutter_tools/lib/src/flutter_manifest.dart
index f3351a322ff..36c25efecef 100644
--- a/packages/flutter_tools/lib/src/flutter_manifest.dart
+++ b/packages/flutter_tools/lib/src/flutter_manifest.dart
@@ -197,7 +197,7 @@ class FlutterManifest {
       return const <Uri>[];
     }
     final List<Uri> results = <Uri>[];
-    for (Object asset in assets) {
+    for (final Object asset in assets) {
       if (asset is! String || asset == null || asset == '') {
         globals.printError('Asset manifest contains a null or empty uri.');
         continue;
@@ -225,7 +225,7 @@ class FlutterManifest {
     }
 
     final List<Font> fonts = <Font>[];
-    for (Map<String, dynamic> fontFamily in _rawFontsDescriptor) {
+    for (final Map<String, dynamic> fontFamily in _rawFontsDescriptor) {
       final YamlList fontFiles = fontFamily['fonts'] as YamlList;
       final String familyName = fontFamily['family'] as String;
       if (familyName == null) {
@@ -238,7 +238,7 @@ class FlutterManifest {
       }
 
       final List<FontAsset> fontAssets = <FontAsset>[];
-      for (Map<dynamic, dynamic> fontFile in fontFiles.cast<Map<dynamic, dynamic>>()) {
+      for (final Map<dynamic, dynamic> fontFile in fontFiles.cast<Map<dynamic, dynamic>>()) {
         final String asset = fontFile['asset'] as String;
         if (asset == null) {
           globals.printError('Warning: Missing asset in fonts for $familyName', emphasis: true);
@@ -431,7 +431,7 @@ void _validateFonts(YamlList fonts, List<String> errors) {
       continue;
     }
     final YamlMap fontMap = fontListEntry as YamlMap;
-    for (dynamic key in fontMap.keys.where((dynamic key) => key != 'family' && key != 'fonts')) {
+    for (final dynamic key in fontMap.keys.where((dynamic key) => key != 'family' && key != 'fonts')) {
       errors.add('Unexpected child "$key" found under "fonts".');
     }
     if (fontMap['family'] != null && fontMap['family'] is! String) {
diff --git a/packages/flutter_tools/lib/src/fuchsia/fuchsia_build.dart b/packages/flutter_tools/lib/src/fuchsia/fuchsia_build.dart
index 24f14196ef7..9ccc04c4896 100644
--- a/packages/flutter_tools/lib/src/fuchsia/fuchsia_build.dart
+++ b/packages/flutter_tools/lib/src/fuchsia/fuchsia_build.dart
@@ -148,7 +148,7 @@ Future<void> _buildAssets(
   await destFile.create(recursive: true);
   final IOSink outFile = destFile.openWrite();
 
-  for (String path in assets.entries.keys) {
+  for (final String path in assets.entries.keys) {
     outFile.write('data/$appName/$path=$assetDir/$path\n');
   }
   await outFile.flush();
diff --git a/packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart b/packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart
index 5ae5a89c205..21e1fbe398f 100644
--- a/packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart
+++ b/packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart
@@ -164,7 +164,7 @@ class FuchsiaDevices extends PollingDeviceDiscovery {
 @visibleForTesting
 List<FuchsiaDevice> parseListDevices(String text) {
   final List<FuchsiaDevice> devices = <FuchsiaDevice>[];
-  for (String rawLine in text.trim().split('\n')) {
+  for (final String rawLine in text.trim().split('\n')) {
     final String line = rawLine.trim();
     // ['ip', 'device name']
     final List<String> words = line.split(' ');
@@ -501,7 +501,7 @@ class FuchsiaDevice extends Device {
       return null;
     }
     final List<int> ports = <int>[];
-    for (String path in findOutput.split('\n')) {
+    for (final String path in findOutput.split('\n')) {
       if (path == '') {
         continue;
       }
@@ -512,7 +512,7 @@ class FuchsiaDevice extends Device {
         return null;
       }
       final String lsOutput = lsResult.stdout;
-      for (String line in lsOutput.split('\n')) {
+      for (final String line in lsOutput.split('\n')) {
         if (line == '') {
           continue;
         }
@@ -557,7 +557,7 @@ class FuchsiaDevice extends Device {
   // TODO(jonahwilliams): replacing this with the hub will require an update
   // to the flutter_runner.
   Future<int> findIsolatePort(String isolateName, List<int> ports) async {
-    for (int port in ports) {
+    for (final int port in ports) {
       try {
         // Note: The square-bracket enclosure for using the IPv6 loopback
         // didn't appear to work, but when assigning to the IPv4 loopback device,
@@ -567,7 +567,7 @@ class FuchsiaDevice extends Device {
         final VMService vmService = await VMService.connect(uri);
         await vmService.getVM();
         await vmService.refreshViews();
-        for (FlutterView flutterView in vmService.vm.views) {
+        for (final FlutterView flutterView in vmService.vm.views) {
           if (flutterView.uiIsolate == null) {
             continue;
           }
@@ -647,7 +647,7 @@ class FuchsiaIsolateDiscoveryProtocol {
 
   Future<void> _findIsolate() async {
     final List<int> ports = await _device.servicePorts();
-    for (int port in ports) {
+    for (final int port in ports) {
       VMService service;
       if (_ports.containsKey(port)) {
         service = _ports[port];
@@ -664,7 +664,7 @@ class FuchsiaIsolateDiscoveryProtocol {
       }
       await service.getVM();
       await service.refreshViews();
-      for (FlutterView flutterView in service.vm.views) {
+      for (final FlutterView flutterView in service.vm.views) {
         if (flutterView.uiIsolate == null) {
           continue;
         }
@@ -753,7 +753,7 @@ class _FuchsiaPortForwarder extends DevicePortForwarder {
 
   @override
   Future<void> dispose() async {
-    for (ForwardedPort port in forwardedPorts) {
+    for (final ForwardedPort port in forwardedPorts) {
       await unforward(port);
     }
   }
diff --git a/packages/flutter_tools/lib/src/fuchsia/tiles_ctl.dart b/packages/flutter_tools/lib/src/fuchsia/tiles_ctl.dart
index 5357a9f5545..21ab56f3b46 100644
--- a/packages/flutter_tools/lib/src/fuchsia/tiles_ctl.dart
+++ b/packages/flutter_tools/lib/src/fuchsia/tiles_ctl.dart
@@ -26,7 +26,7 @@ class FuchsiaTilesCtl {
       globals.printTrace('tiles_ctl is not running');
       return -1;
     }
-    for (MapEntry<int, String> entry in runningApps.entries) {
+    for (final MapEntry<int, String> entry in runningApps.entries) {
       if (entry.value.contains('$appName#meta')) {
         return entry.key;
       }
@@ -70,7 +70,7 @@ class FuchsiaTilesCtl {
       return null;
     }
     // Find lines beginning with 'Tile'
-    for (String line in result.stdout.split('\n')) {
+    for (final String line in result.stdout.split('\n')) {
       final List<String> words = line.split(' ');
       if (words.isNotEmpty && words[0] == 'Tile') {
         final int key = int.tryParse(words[2]);
diff --git a/packages/flutter_tools/lib/src/intellij/intellij.dart b/packages/flutter_tools/lib/src/intellij/intellij.dart
index aa2fd203161..48a9a50d753 100644
--- a/packages/flutter_tools/lib/src/intellij/intellij.dart
+++ b/packages/flutter_tools/lib/src/intellij/intellij.dart
@@ -22,7 +22,7 @@ class IntelliJPlugins {
     String title, {
     Version minVersion,
   }) {
-    for (String packageName in packageNames) {
+    for (final String packageName in packageNames) {
       if (!_hasPackage(packageName)) {
         continue;
       }
diff --git a/packages/flutter_tools/lib/src/ios/devices.dart b/packages/flutter_tools/lib/src/ios/devices.dart
index 5b5fd275f21..c9b43412890 100644
--- a/packages/flutter_tools/lib/src/ios/devices.dart
+++ b/packages/flutter_tools/lib/src/ios/devices.dart
@@ -660,7 +660,7 @@ class IOSDeviceLogReader extends DeviceLogReader {
 
   @override
   void dispose() {
-    for (StreamSubscription<ServiceEvent> loggingSubscription in _loggingSubscriptions) {
+    for (final StreamSubscription<ServiceEvent> loggingSubscription in _loggingSubscriptions) {
       loggingSubscription.cancel();
     }
     _idevicesyslogProcess?.kill();
@@ -747,7 +747,7 @@ class IOSDevicePortForwarder extends DevicePortForwarder {
 
   @override
   Future<void> dispose() async {
-    for (ForwardedPort forwardedPort in _forwardedPorts) {
+    for (final ForwardedPort forwardedPort in _forwardedPorts) {
       forwardedPort.dispose();
     }
   }
diff --git a/packages/flutter_tools/lib/src/ios/mac.dart b/packages/flutter_tools/lib/src/ios/mac.dart
index 7974313e3f5..a220b42f4a1 100644
--- a/packages/flutter_tools/lib/src/ios/mac.dart
+++ b/packages/flutter_tools/lib/src/ios/mac.dart
@@ -371,7 +371,7 @@ Future<XcodeBuildResult> buildXcodeProject({
   }
 
   if (autoSigningConfigs != null) {
-    for (MapEntry<String, String> signingConfig in autoSigningConfigs.entries) {
+    for (final MapEntry<String, String> signingConfig in autoSigningConfigs.entries) {
       buildCommands.add('${signingConfig.key}=${signingConfig.value}');
     }
     buildCommands.add('-allowProvisioningUpdates');
@@ -379,7 +379,7 @@ Future<XcodeBuildResult> buildXcodeProject({
   }
 
   final List<FileSystemEntity> contents = app.project.hostAppRoot.listSync();
-  for (FileSystemEntity entity in contents) {
+  for (final FileSystemEntity entity in contents) {
     if (globals.fs.path.extension(entity.path) == '.xcworkspace') {
       buildCommands.addAll(<String>[
         '-workspace', globals.fs.path.basename(entity.path),
@@ -426,7 +426,7 @@ Future<XcodeBuildResult> buildXcodeProject({
 
     Future<void> listenToScriptOutputLine() async {
       final List<String> lines = await scriptOutputPipeFile.readAsLines();
-      for (String line in lines) {
+      for (final String line in lines) {
         if (line == 'done' || line == 'all done') {
           buildSubStatus?.stop();
           buildSubStatus = null;
diff --git a/packages/flutter_tools/lib/src/ios/simulators.dart b/packages/flutter_tools/lib/src/ios/simulators.dart
index 748d1dcc87b..72b7aa61cad 100644
--- a/packages/flutter_tools/lib/src/ios/simulators.dart
+++ b/packages/flutter_tools/lib/src/ios/simulators.dart
@@ -112,10 +112,10 @@ class SimControl {
 
     final Map<String, dynamic> devicesSection = await _list(SimControlListSection.devices);
 
-    for (String deviceCategory in devicesSection.keys) {
+    for (final String deviceCategory in devicesSection.keys) {
       final Object devicesData = devicesSection[deviceCategory];
       if (devicesData != null && devicesData is List<dynamic>) {
-        for (Map<String, dynamic> data in devicesData.map<Map<String, dynamic>>(castStringKeyedMap)) {
+        for (final Map<String, dynamic> data in devicesData.map<Map<String, dynamic>>(castStringKeyedMap)) {
           devices.add(SimDevice(deviceCategory, data));
         }
       }
@@ -809,7 +809,7 @@ class _IOSSimulatorDevicePortForwarder extends DevicePortForwarder {
 
   @override
   Future<void> dispose() async {
-    for (ForwardedPort port in _ports) {
+    for (final ForwardedPort port in _ports) {
       await unforward(port);
     }
   }
diff --git a/packages/flutter_tools/lib/src/ios/xcodeproj.dart b/packages/flutter_tools/lib/src/ios/xcodeproj.dart
index ff966cbdda7..09b50ca1bd5 100644
--- a/packages/flutter_tools/lib/src/ios/xcodeproj.dart
+++ b/packages/flutter_tools/lib/src/ios/xcodeproj.dart
@@ -106,7 +106,7 @@ void _updateGeneratedEnvironmentVariablesScript({
 
   localsBuffer.writeln('#!/bin/sh');
   localsBuffer.writeln('# This is a generated file; do not edit or check into version control.');
-  for (String line in xcodeBuildSettings) {
+  for (final String line in xcodeBuildSettings) {
     localsBuffer.writeln('export "$line"');
   }
 
@@ -372,7 +372,7 @@ List<String> environmentVariablesAsXcodeBuildSettings() {
 
 Map<String, String> parseXcodeBuildSettings(String showBuildSettingsOutput) {
   final Map<String, String> settings = <String, String>{};
-  for (Match match in showBuildSettingsOutput.split('\n').map<Match>(_settingExpr.firstMatch)) {
+  for (final Match match in showBuildSettingsOutput.split('\n').map<Match>(_settingExpr.firstMatch)) {
     if (match != null) {
       settings[match[1]] = match[2];
     }
@@ -402,7 +402,7 @@ class XcodeProjectInfo {
     final List<String> buildConfigurations = <String>[];
     final List<String> schemes = <String>[];
     List<String> collector;
-    for (String line in output.split('\n')) {
+    for (final String line in output.split('\n')) {
       if (line.isEmpty) {
         collector = null;
         continue;
@@ -454,7 +454,7 @@ class XcodeProjectInfo {
   /// regard to case.
   bool hasBuildConfiguratinForBuildMode(String buildMode) {
     buildMode = buildMode.toLowerCase();
-    for (String name in buildConfigurations) {
+    for (final String name in buildConfigurations) {
       if (name.toLowerCase() == buildMode) {
         return true;
       }
diff --git a/packages/flutter_tools/lib/src/linux/makefile.dart b/packages/flutter_tools/lib/src/linux/makefile.dart
index 3569082b7ab..94331ac1d97 100644
--- a/packages/flutter_tools/lib/src/linux/makefile.dart
+++ b/packages/flutter_tools/lib/src/linux/makefile.dart
@@ -11,7 +11,7 @@ const String _kBinaryNameVariable = 'BINARY_NAME=';
 ///
 /// Returns `null` if it cannot be found.
 String makefileExecutableName(LinuxProject project) {
-  for (String line in project.makeFile.readAsLinesSync()) {
+  for (final String line in project.makeFile.readAsLinesSync()) {
     if (line.startsWith(_kBinaryNameVariable)) {
       return line.split(_kBinaryNameVariable).last.trim();
     }
diff --git a/packages/flutter_tools/lib/src/mdns_discovery.dart b/packages/flutter_tools/lib/src/mdns_discovery.dart
index 033e0977039..dea4976803a 100644
--- a/packages/flutter_tools/lib/src/mdns_discovery.dart
+++ b/packages/flutter_tools/lib/src/mdns_discovery.dart
@@ -75,7 +75,7 @@ class MDnsObservatoryDiscovery {
 
       String domainName;
       if (applicationId != null) {
-        for (String name in uniqueDomainNames) {
+        for (final String name in uniqueDomainNames) {
           if (name.toLowerCase().startsWith(applicationId.toLowerCase())) {
             domainName = name;
             break;
@@ -206,10 +206,10 @@ class MDnsObservatoryDiscovery {
   }
 
   void _logInterfaces(List<NetworkInterface> interfaces) {
-    for (NetworkInterface interface in interfaces) {
+    for (final NetworkInterface interface in interfaces) {
       if (globals.logger.isVerbose) {
         globals.printTrace('Found interface "${interface.name}":');
-        for (InternetAddress address in interface.addresses) {
+        for (final InternetAddress address in interface.addresses) {
           final String linkLocal = address.isLinkLocal ? 'link local' : '';
           globals.printTrace('\tBound address: "${address.address}" $linkLocal');
         }
diff --git a/packages/flutter_tools/lib/src/plugins.dart b/packages/flutter_tools/lib/src/plugins.dart
index 22f506b790e..cd7eb4361dc 100644
--- a/packages/flutter_tools/lib/src/plugins.dart
+++ b/packages/flutter_tools/lib/src/plugins.dart
@@ -321,10 +321,10 @@ bool _writeFlutterPluginsList(FlutterProject project, List<Plugin> plugins) {
   final StringBuffer flutterPluginsBuffer = StringBuffer('# $info\n');
 
   final Set<String> pluginNames = <String>{};
-  for (Plugin plugin in plugins) {
+  for (final Plugin plugin in plugins) {
     pluginNames.add(plugin.name);
   }
-  for (Plugin plugin in plugins) {
+  for (final Plugin plugin in plugins) {
     flutterPluginsBuffer.write('${plugin.name}=${escapePath(plugin.path)}\n');
     directAppDependencies.add(<String, dynamic>{
       'name': plugin.name,
@@ -439,7 +439,7 @@ public final class GeneratedPluginRegistrant {
 
 List<Map<String, dynamic>> _extractPlatformMaps(List<Plugin> plugins, String type) {
   final List<Map<String, dynamic>> pluginConfigs = <Map<String, dynamic>>[];
-  for (Plugin p in plugins) {
+  for (final Plugin p in plugins) {
     final PluginPlatform platformPlugin = p.platforms[type];
     if (platformPlugin != null) {
       pluginConfigs.add(platformPlugin.toMap());
@@ -484,7 +484,7 @@ Future<void> _writeAndroidPluginRegistrant(FlutterProject project, List<Plugin>
       templateContext['needsShim'] = false;
       // If a plugin is using an embedding version older than 2.0 and the app is using 2.0,
       // then add shim for the old plugins.
-      for (Map<String, dynamic> plugin in androidPlugins) {
+      for (final Map<String, dynamic> plugin in androidPlugins) {
         if (plugin['supportsEmbeddingV1'] as bool && !(plugin['supportsEmbeddingV2'] as bool)) {
           templateContext['needsShim'] = true;
           if (project.isModule) {
@@ -504,7 +504,7 @@ Future<void> _writeAndroidPluginRegistrant(FlutterProject project, List<Plugin>
       break;
     case AndroidEmbeddingVersion.v1:
     default:
-      for (Map<String, dynamic> plugin in androidPlugins) {
+      for (final Map<String, dynamic> plugin in androidPlugins) {
         if (!(plugin['supportsEmbeddingV1'] as bool) && plugin['supportsEmbeddingV2'] as bool) {
           throwToolExit(
             'The plugin `${plugin['name']}` requires your app to be migrated to '
diff --git a/packages/flutter_tools/lib/src/project.dart b/packages/flutter_tools/lib/src/project.dart
index 234a266aa6b..6d14011e9c9 100644
--- a/packages/flutter_tools/lib/src/project.dart
+++ b/packages/flutter_tools/lib/src/project.dart
@@ -699,7 +699,7 @@ class AndroidProject {
       throwToolExit('Error reading $appManifestFile even though it exists. '
                     'Please ensure that you have read permission to this file and try again.');
     }
-    for (xml.XmlElement metaData in document.findAllElements('meta-data')) {
+    for (final xml.XmlElement metaData in document.findAllElements('meta-data')) {
       final String name = metaData.getAttribute('android:name');
       if (name == 'flutterEmbedding') {
         final String embeddingVersionString = metaData.getAttribute('android:value');
@@ -764,7 +764,7 @@ Match _firstMatchInFile(File file, RegExp regExp) {
   if (!file.existsSync()) {
     return null;
   }
-  for (String line in file.readAsLinesSync()) {
+  for (final String line in file.readAsLinesSync()) {
     final Match match = regExp.firstMatch(line);
     if (match != null) {
       return match;
diff --git a/packages/flutter_tools/lib/src/protocol_discovery.dart b/packages/flutter_tools/lib/src/protocol_discovery.dart
index 6133048b36f..a13878e47e4 100644
--- a/packages/flutter_tools/lib/src/protocol_discovery.dart
+++ b/packages/flutter_tools/lib/src/protocol_discovery.dart
@@ -157,7 +157,7 @@ class _BufferedStreamController<T> {
 
   StreamController<T> get _streamController {
     _streamControllerInstance ??= StreamController<T>.broadcast(onListen: () {
-      for (dynamic event in _events) {
+      for (final dynamic event in _events) {
         assert(T is! List);
         if (event is T) {
           _streamControllerInstance.add(event);
diff --git a/packages/flutter_tools/lib/src/proxy_validator.dart b/packages/flutter_tools/lib/src/proxy_validator.dart
index 3a8931e43a8..95896f2c111 100644
--- a/packages/flutter_tools/lib/src/proxy_validator.dart
+++ b/packages/flutter_tools/lib/src/proxy_validator.dart
@@ -34,7 +34,7 @@ class ProxyValidator extends DoctorValidator {
         messages.add(ValidationMessage.hint('NO_PROXY is not set'));
       } else {
         messages.add(ValidationMessage('NO_PROXY is $_noProxy'));
-        for (String host in const <String>['127.0.0.1', 'localhost']) {
+        for (final String host in const <String>['127.0.0.1', 'localhost']) {
           final ValidationMessage msg = _noProxy.contains(host)
               ? ValidationMessage('NO_PROXY contains $host')
               : ValidationMessage.hint('NO_PROXY does not contain $host');
diff --git a/packages/flutter_tools/lib/src/reporting/github_template.dart b/packages/flutter_tools/lib/src/reporting/github_template.dart
index 367232ed1ea..ff35e3b2686 100644
--- a/packages/flutter_tools/lib/src/reporting/github_template.dart
+++ b/packages/flutter_tools/lib/src/reporting/github_template.dart
@@ -99,7 +99,7 @@ ${_projectMetadataInformation()}
         description.writeln('### Plugins');
         // Format is:
         // camera=/path/to/.pub-cache/hosted/pub.dartlang.org/camera-0.5.7+2/
-        for (String plugin in project.flutterPluginsFile.readAsLinesSync()) {
+        for (final String plugin in project.flutterPluginsFile.readAsLinesSync()) {
           final List<String> pluginParts = plugin.split('=');
           if (pluginParts.length != 2) {
             continue;
diff --git a/packages/flutter_tools/lib/src/resident_runner.dart b/packages/flutter_tools/lib/src/resident_runner.dart
index 15e4b036b5c..9e4669447f8 100644
--- a/packages/flutter_tools/lib/src/resident_runner.dart
+++ b/packages/flutter_tools/lib/src/resident_runner.dart
@@ -249,7 +249,7 @@ class FlutterDevice {
       return;
     }
     final List<Future<void>> futures = <Future<void>>[];
-    for (FlutterView view in flutterViews) {
+    for (final FlutterView view in flutterViews) {
       if (view != null && view.uiIsolate != null) {
         assert(!view.uiIsolate.pauseEvent.isPauseEvent);
         futures.add(view.uiIsolate.flutterExit());
@@ -283,7 +283,7 @@ class FlutterDevice {
     final Uri deviceEntryUri = devFS.baseUri.resolveUri(globals.fs.path.toUri(entryPath));
     final Uri devicePackagesUri = devFS.baseUri.resolve('.packages');
     return <Future<Map<String, dynamic>>>[
-      for (FlutterView view in views)
+      for (final FlutterView view in views)
         view.uiIsolate.reloadSources(
           pause: pause,
           rootLibUri: deviceEntryUri,
@@ -302,68 +302,68 @@ class FlutterDevice {
   }
 
   Future<void> debugDumpApp() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterDebugDumpApp();
     }
   }
 
   Future<void> debugDumpRenderTree() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterDebugDumpRenderTree();
     }
   }
 
   Future<void> debugDumpLayerTree() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterDebugDumpLayerTree();
     }
   }
 
   Future<void> debugDumpSemanticsTreeInTraversalOrder() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterDebugDumpSemanticsTreeInTraversalOrder();
     }
   }
 
   Future<void> debugDumpSemanticsTreeInInverseHitTestOrder() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterDebugDumpSemanticsTreeInInverseHitTestOrder();
     }
   }
 
   Future<void> toggleDebugPaintSizeEnabled() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterToggleDebugPaintSizeEnabled();
     }
   }
 
   Future<void> toggleDebugCheckElevationsEnabled() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterToggleDebugCheckElevationsEnabled();
     }
   }
 
   Future<void> debugTogglePerformanceOverlayOverride() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterTogglePerformanceOverlayOverride();
     }
   }
 
   Future<void> toggleWidgetInspector() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterToggleWidgetInspector();
     }
   }
 
   Future<void> toggleProfileWidgetBuilds() async {
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterToggleProfileWidgetBuilds();
     }
   }
 
   Future<String> togglePlatform({ String from }) async {
     final String to = nextPlatform(from, featureFlags);
-    for (FlutterView view in views) {
+    for (final FlutterView view in views) {
       await view.uiIsolate.flutterPlatformOverride(to);
     }
     return to;
@@ -578,7 +578,7 @@ final RegExp kAndroidQHttpConnectionClosedExp = RegExp(r'^HttpException\:.+\, ur
 
 /// Returns `true` if any of the devices is running Android Q.
 Future<bool> hasDeviceRunningAndroidQ(List<FlutterDevice> flutterDevices) async {
-  for (FlutterDevice flutterDevice in flutterDevices) {
+  for (final FlutterDevice flutterDevice in flutterDevices) {
     final String sdkNameAndVersion = await flutterDevice.device.sdkNameAndVersion;
     if (sdkNameAndVersion != null && sdkNameAndVersion.startsWith('Android 10')) {
       return true;
@@ -755,77 +755,77 @@ abstract class ResidentRunner {
 
   Future<void> refreshViews() async {
     final List<Future<void>> futures = <Future<void>>[
-      for (FlutterDevice device in flutterDevices) device.refreshViews(),
+      for (final FlutterDevice device in flutterDevices) device.refreshViews(),
     ];
     await Future.wait(futures);
   }
 
   Future<void> debugDumpApp() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.debugDumpApp();
     }
   }
 
   Future<void> debugDumpRenderTree() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.debugDumpRenderTree();
     }
   }
 
   Future<void> debugDumpLayerTree() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.debugDumpLayerTree();
     }
   }
 
   Future<void> debugDumpSemanticsTreeInTraversalOrder() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.debugDumpSemanticsTreeInTraversalOrder();
     }
   }
 
   Future<void> debugDumpSemanticsTreeInInverseHitTestOrder() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.debugDumpSemanticsTreeInInverseHitTestOrder();
     }
   }
 
   Future<void> debugToggleDebugPaintSizeEnabled() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.toggleDebugPaintSizeEnabled();
     }
   }
 
   Future<void> debugToggleDebugCheckElevationsEnabled() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.toggleDebugCheckElevationsEnabled();
     }
   }
 
   Future<void> debugTogglePerformanceOverlayOverride() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.debugTogglePerformanceOverlayOverride();
     }
   }
 
   Future<void> debugToggleWidgetInspector() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.toggleWidgetInspector();
     }
   }
 
   Future<void> debugToggleProfileWidgetBuilds() async {
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.toggleProfileWidgetBuilds();
     }
   }
@@ -845,7 +845,7 @@ abstract class ResidentRunner {
       if (supportsServiceProtocol && isRunningDebug) {
         await device.refreshViews();
         try {
-          for (FlutterView view in device.views) {
+          for (final FlutterView view in device.views) {
             await view.uiIsolate.flutterDebugAllowBanner(false);
           }
         } catch (error) {
@@ -859,7 +859,7 @@ abstract class ResidentRunner {
       } finally {
         if (supportsServiceProtocol && isRunningDebug) {
           try {
-            for (FlutterView view in device.views) {
+            for (final FlutterView view in device.views) {
               await view.uiIsolate.flutterDebugAllowBanner(true);
             }
           } catch (error) {
@@ -882,7 +882,7 @@ abstract class ResidentRunner {
     await refreshViews();
     final String from = await flutterDevices[0].views[0].uiIsolate.flutterPlatformOverride();
     String to;
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       to = await device.togglePlatform(from: from);
     }
     globals.printStatus('Switched operating system to $to');
@@ -913,7 +913,7 @@ abstract class ResidentRunner {
     _finished = Completer<int>();
 
     bool viewFound = false;
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       await device.connect(
         reloadSources: reloadSources,
         restart: restart,
@@ -935,7 +935,7 @@ abstract class ResidentRunner {
     }
 
     // Listen for service protocol connection to close.
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       // This hooks up callbacks for when the connection stops in the future.
       // We don't want to wait for them. We don't handle errors in those callbacks'
       // futures either because they just print to logger and is not critical.
@@ -993,7 +993,7 @@ abstract class ResidentRunner {
 
   Future<void> exitApp() async {
     final List<Future<void>> futures = <Future<void>>[
-      for (FlutterDevice device in flutterDevices)  device.exitApps(),
+      for (final FlutterDevice device in flutterDevices)  device.exitApps(),
     ];
     await Future.wait(futures);
     appFinished();
@@ -1116,7 +1116,7 @@ class TerminalHandler {
   /// Unregisters terminal signal and keystroke handlers.
   void stop() {
     assert(residentRunner.stayResident);
-    for (MapEntry<io.ProcessSignal, Object> entry in _signalTokens.entries) {
+    for (final MapEntry<io.ProcessSignal, Object> entry in _signalTokens.entries) {
       signals.removeHandler(entry.key, entry.value);
     }
     _signalTokens.clear();
@@ -1154,7 +1154,7 @@ class TerminalHandler {
         final List<FlutterView> views = residentRunner.flutterDevices
             .expand((FlutterDevice d) => d.views).toList();
         globals.printStatus('Connected ${pluralize('view', views.length)}:');
-        for (FlutterView v in views) {
+        for (final FlutterView v in views) {
           globals.printStatus('${v.uiIsolate.name} (${v.uiIsolate.id})', indent: 2);
         }
         return true;
@@ -1189,7 +1189,7 @@ class TerminalHandler {
         await residentRunner.exit();
         return true;
       case 's':
-        for (FlutterDevice device in residentRunner.flutterDevices) {
+        for (final FlutterDevice device in residentRunner.flutterDevices) {
           if (device.device.supportsScreenshot) {
             await residentRunner.screenshot(device);
           }
diff --git a/packages/flutter_tools/lib/src/run_cold.dart b/packages/flutter_tools/lib/src/run_cold.dart
index 02f95ae8f3c..12114527ca8 100644
--- a/packages/flutter_tools/lib/src/run_cold.dart
+++ b/packages/flutter_tools/lib/src/run_cold.dart
@@ -60,7 +60,7 @@ class ColdRunner extends ResidentRunner {
       }
     }
 
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       final int result = await device.runCold(
         coldRunner: this,
         route: route,
@@ -90,7 +90,7 @@ class ColdRunner extends ResidentRunner {
 
     globals.printTrace('Application running.');
 
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       if (device.vmService == null) {
         continue;
       }
@@ -142,12 +142,12 @@ class ColdRunner extends ResidentRunner {
       }
       return 2;
     }
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       device.initLogReader();
     }
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
-      for (FlutterView view in device.views) {
+    for (final FlutterDevice device in flutterDevices) {
+      for (final FlutterView view in device.views) {
         globals.printTrace('Connected to $view.');
       }
     }
@@ -170,7 +170,7 @@ class ColdRunner extends ResidentRunner {
 
   @override
   Future<void> cleanupAtFinish() async {
-    for (FlutterDevice flutterDevice in flutterDevices) {
+    for (final FlutterDevice flutterDevice in flutterDevices) {
       await flutterDevice.device.dispose();
     }
 
@@ -181,7 +181,7 @@ class ColdRunner extends ResidentRunner {
   void printHelp({ @required bool details }) {
     bool haveDetails = false;
     bool haveAnything = false;
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       final String dname = device.device.name;
       if (device.vmService != null) {
         globals.printStatus('An Observatory debugger and profiler on $dname is '
@@ -209,7 +209,7 @@ class ColdRunner extends ResidentRunner {
 
   @override
   Future<void> preExit() async {
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       // If we're running in release mode, stop the app using the device logic.
       if (device.vmService == null) {
         await device.device.stopApp(device.package);
diff --git a/packages/flutter_tools/lib/src/run_hot.dart b/packages/flutter_tools/lib/src/run_hot.dart
index e8d933713a7..2eadea5a9f8 100644
--- a/packages/flutter_tools/lib/src/run_hot.dart
+++ b/packages/flutter_tools/lib/src/run_hot.dart
@@ -137,7 +137,7 @@ class HotRunner extends ResidentRunner {
     String klass,
     bool isStatic,
   ) async {
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       if (device.generator != null) {
         final CompilerOutput compilerOutput =
             await device.generator.compileExpression(expression, definitions,
@@ -155,7 +155,7 @@ class HotRunner extends ResidentRunner {
     final Stopwatch stopwatch = Stopwatch()..start();
     final UpdateFSReport results = UpdateFSReport(success: true);
     final List<Uri> invalidated =  <Uri>[Uri.parse(libraryId)];
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       results.incorporateResults(await device.updateDevFS(
         mainPath: mainPath,
         target: target,
@@ -178,7 +178,7 @@ class HotRunner extends ResidentRunner {
         getReloadPath(fullRestart: false),
         from: projectRootPath,
       );
-      for (FlutterDevice device in flutterDevices) {
+      for (final FlutterDevice device in flutterDevices) {
         final List<Future<Map<String, dynamic>>> reportFutures = device.reloadSources(
           entryPath, pause: false,
         );
@@ -190,8 +190,8 @@ class HotRunner extends ResidentRunner {
       return OperationResult(1, error.toString());
     }
 
-    for (FlutterDevice device in flutterDevices) {
-      for (FlutterView view in device.views) {
+    for (final FlutterDevice device in flutterDevices) {
+      for (final FlutterView view in device.views) {
         await view.uiIsolate.flutterFastReassemble(classId);
       }
     }
@@ -227,7 +227,7 @@ class HotRunner extends ResidentRunner {
       return 2;
     }
 
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       device.initLogReader();
     }
     try {
@@ -257,13 +257,13 @@ class HotRunner extends ResidentRunner {
     }
 
     await refreshViews();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       // VM must have accepted the kernel binary, there will be no reload
       // report, so we let incremental compiler know that source code was accepted.
       if (device.generator != null) {
         device.generator.accept();
       }
-      for (FlutterView view in device.views) {
+      for (final FlutterView view in device.views) {
         globals.printTrace('Connected to $view.');
       }
     }
@@ -330,7 +330,7 @@ class HotRunner extends ResidentRunner {
 
     firstBuildTime = DateTime.now();
 
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       final int result = await device.runHot(
         hotRunner: this,
         route: route,
@@ -349,7 +349,7 @@ class HotRunner extends ResidentRunner {
   Future<List<Uri>> _initDevFS() async {
     final String fsName = globals.fs.path.basename(projectRootPath);
     return <Uri>[
-      for (FlutterDevice device in flutterDevices)
+      for (final FlutterDevice device in flutterDevices)
         await device.setupDevFS(
           fsName,
           globals.fs.directory(projectRootPath),
@@ -378,7 +378,7 @@ class HotRunner extends ResidentRunner {
       asyncScanning: hotRunnerConfig.asyncScanning,
     );
     final UpdateFSReport results = UpdateFSReport(success: true);
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       results.incorporateResults(await device.updateDevFS(
         mainPath: mainPath,
         target: target,
@@ -397,14 +397,14 @@ class HotRunner extends ResidentRunner {
   }
 
   void _resetDirtyAssets() {
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       device.devFS.assetPathsToEvict.clear();
     }
   }
 
   Future<void> _cleanupDevFS() async {
     final List<Future<void>> futures = <Future<void>>[];
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       if (device.devFS != null) {
         // Cleanup the devFS, but don't wait indefinitely.
         // We ignore any errors, because it's not clear what we would do anyway.
@@ -426,7 +426,7 @@ class HotRunner extends ResidentRunner {
     Uri assetsDirectoryUri,
   ) {
     return Future.wait(<Future<void>>[
-      for (FlutterView view in device.views)
+      for (final FlutterView view in device.views)
         view.runFromSource(entryUri, packagesUri, assetsDirectoryUri),
     ]);
   }
@@ -434,7 +434,7 @@ class HotRunner extends ResidentRunner {
   Future<void> _launchFromDevFS(String mainScript) async {
     final String entryUri = globals.fs.path.relative(mainScript, from: projectRootPath);
     final List<Future<void>> futures = <Future<void>>[];
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       final Uri deviceEntryUri = device.devFS.baseUri.resolveUri(
         globals.fs.path.toUri(entryUri));
       final Uri devicePackagesUri = device.devFS.baseUri.resolve('.packages');
@@ -448,8 +448,8 @@ class HotRunner extends ResidentRunner {
     await Future.wait(futures);
     if (benchmarkMode) {
       futures.clear();
-      for (FlutterDevice device in flutterDevices) {
-        for (FlutterView view in device.views) {
+      for (final FlutterDevice device in flutterDevices) {
+        for (final FlutterView view in device.views) {
           futures.add(view.flushUIThreadTasks());
         }
       }
@@ -471,7 +471,7 @@ class HotRunner extends ResidentRunner {
     // compiler for full application recompilation on restart.
     final UpdateFSReport updatedDevFS = await _updateDevFS(fullRestart: true);
     if (!updatedDevFS.success) {
-      for (FlutterDevice device in flutterDevices) {
+      for (final FlutterDevice device in flutterDevices) {
         if (device.generator != null) {
           await device.generator.reject();
         }
@@ -479,7 +479,7 @@ class HotRunner extends ResidentRunner {
       return OperationResult(1, 'DevFS synchronization failed');
     }
     _resetDirtyAssets();
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       // VM must have accepted the kernel binary, there will be no reload
       // report, so we let incremental compiler know that source code was accepted.
       if (device.generator != null) {
@@ -488,8 +488,8 @@ class HotRunner extends ResidentRunner {
     }
     // Check if the isolate is paused and resume it.
     final List<Future<void>> futures = <Future<void>>[];
-    for (FlutterDevice device in flutterDevices) {
-      for (FlutterView view in device.views) {
+    for (final FlutterDevice device in flutterDevices) {
+      for (final FlutterView view in device.views) {
         if (view.uiIsolate == null) {
           continue;
         }
@@ -522,12 +522,12 @@ class HotRunner extends ResidentRunner {
     // In benchmark mode, make sure all stream notifications have finished.
     if (benchmarkMode) {
       final List<Future<void>> isolateNotifications = <Future<void>>[];
-      for (FlutterDevice device in flutterDevices) {
-        for (FlutterView view in device.views) {
+      for (final FlutterDevice device in flutterDevices) {
+        for (final FlutterView view in device.views) {
           isolateNotifications.add(
             view.owner.vm.vmService.onIsolateEvent
               .then((Stream<ServiceEvent> serviceEvents) async {
-              await for (ServiceEvent serviceEvent in serviceEvents) {
+              await for (final ServiceEvent serviceEvent in serviceEvents) {
                 if (serviceEvent.owner.name.contains('_spawn')
                   && serviceEvent.kind == ServiceEvent.kIsolateExit) {
                   return;
@@ -575,7 +575,7 @@ class HotRunner extends ResidentRunner {
     if (!(reloadReport['success'] as bool)) {
       if (printErrors) {
         globals.printError('Hot reload was rejected:');
-        for (Map<String, dynamic> notice in reloadReport['details']['notices']) {
+        for (final Map<String, dynamic> notice in reloadReport['details']['notices']) {
           globals.printError('${notice['message']}');
         }
       }
@@ -747,8 +747,8 @@ class HotRunner extends ResidentRunner {
     String reason,
     void Function(String message) onSlow,
   }) async {
-    for (FlutterDevice device in flutterDevices) {
-      for (FlutterView view in device.views) {
+    for (final FlutterDevice device in flutterDevices) {
+      for (final FlutterView view in device.views) {
         if (view.uiIsolate == null) {
           return OperationResult(2, 'Application isolate not found', fatal: true);
         }
@@ -785,7 +785,7 @@ class HotRunner extends ResidentRunner {
         from: projectRootPath,
       );
       final List<Future<DeviceReloadReport>> allReportsFutures = <Future<DeviceReloadReport>>[];
-      for (FlutterDevice device in flutterDevices) {
+      for (final FlutterDevice device in flutterDevices) {
         if (_runningFromSnapshot) {
           // Asset directory has to be set only once when we switch from
           // running from snapshot to running from uploaded files.
@@ -809,7 +809,7 @@ class HotRunner extends ResidentRunner {
         ));
       }
       final List<DeviceReloadReport> reports = await Future.wait(allReportsFutures);
-      for (DeviceReloadReport report in reports) {
+      for (final DeviceReloadReport report in reports) {
         final Map<String, dynamic> reloadReport = report.reports[0];
         if (!validateReloadReport(reloadReport)) {
           // Reload failed.
@@ -859,10 +859,10 @@ class HotRunner extends ResidentRunner {
     final Stopwatch reassembleTimer = Stopwatch()..start();
     // Reload the isolate.
     final List<Future<void>> allDevices = <Future<void>>[];
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       globals.printTrace('Sending reload events to ${device.device.name}');
       final List<Future<ServiceObject>> futuresViews = <Future<ServiceObject>>[];
-      for (FlutterView view in device.views) {
+      for (final FlutterView view in device.views) {
         globals.printTrace('Sending reload event to "${view.uiIsolate.name}"');
         futuresViews.add(view.uiIsolate.reload());
       }
@@ -878,8 +878,8 @@ class HotRunner extends ResidentRunner {
     final List<FlutterView> reassembleViews = <FlutterView>[];
     String serviceEventKind;
     int pausedIsolatesFound = 0;
-    for (FlutterDevice device in flutterDevices) {
-      for (FlutterView view in device.views) {
+    for (final FlutterDevice device in flutterDevices) {
+      for (final FlutterView view in device.views) {
         // Check if the isolate is paused, and if so, don't reassemble. Ignore the
         // PostPauseEvent event - the client requesting the pause will resume the app.
         final ServiceEvent pauseEvent = view.uiIsolate.pauseEvent;
@@ -910,7 +910,7 @@ class HotRunner extends ResidentRunner {
     globals.printTrace('Reassembling application');
     bool failedReassemble = false;
     final List<Future<void>> futures = <Future<void>>[
-      for (FlutterView view in reassembleViews)
+      for (final FlutterView view in reassembleViews)
         () async {
           try {
             await view.uiIsolate.flutterReassemble();
@@ -933,7 +933,7 @@ class HotRunner extends ResidentRunner {
         globals.printTrace('This is taking a long time; will now check for paused isolates.');
         int postReloadPausedIsolatesFound = 0;
         String serviceEventKind;
-        for (FlutterView view in reassembleViews) {
+        for (final FlutterView view in reassembleViews) {
           await view.uiIsolate.reload();
           final ServiceEvent pauseEvent = view.uiIsolate.pauseEvent;
           if (pauseEvent != null && pauseEvent.isPauseEvent) {
@@ -1030,8 +1030,8 @@ class HotRunner extends ResidentRunner {
   }
 
   bool _isPaused() {
-    for (FlutterDevice device in flutterDevices) {
-      for (FlutterView view in device.views) {
+    for (final FlutterDevice device in flutterDevices) {
+      for (final FlutterView view in device.views) {
         if (view.uiIsolate != null) {
           final ServiceEvent pauseEvent = view.uiIsolate.pauseEvent;
           if (pauseEvent != null && pauseEvent.isPauseEvent) {
@@ -1055,7 +1055,7 @@ class HotRunner extends ResidentRunner {
       TerminalColor.red,
     );
     globals.printStatus(message);
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       final String dname = device.device.name;
       globals.printStatus('An Observatory debugger and profiler on $dname is '
         'available at: ${device.vmService.httpAddress}');
@@ -1073,7 +1073,7 @@ class HotRunner extends ResidentRunner {
 
   Future<void> _evictDirtyAssets() {
     final List<Future<Map<String, dynamic>>> futures = <Future<Map<String, dynamic>>>[];
-    for (FlutterDevice device in flutterDevices) {
+    for (final FlutterDevice device in flutterDevices) {
       if (device.devFS.assetPathsToEvict.isEmpty) {
         continue;
       }
@@ -1081,7 +1081,7 @@ class HotRunner extends ResidentRunner {
         globals.printError('Application isolate not found for $device');
         continue;
       }
-      for (String assetPath in device.devFS.assetPathsToEvict) {
+      for (final String assetPath in device.devFS.assetPathsToEvict) {
         futures.add(device.views.first.uiIsolate.flutterEvictAsset(assetPath));
       }
       device.devFS.assetPathsToEvict.clear();
@@ -1109,7 +1109,7 @@ class HotRunner extends ResidentRunner {
 
   @override
   Future<void> cleanupAtFinish() async {
-    for (FlutterDevice flutterDevice in flutterDevices) {
+    for (final FlutterDevice flutterDevice in flutterDevices) {
       await flutterDevice.device.dispose();
     }
     await _cleanupDevFS();
@@ -1161,7 +1161,7 @@ class ProjectFileInvalidator {
     final Stopwatch stopwatch = Stopwatch()..start();
     final List<Uri> urisToScan = <Uri>[
       // Don't watch pub cache directories to speed things up a little.
-      for (Uri uri in urisToMonitor)
+      for (final Uri uri in urisToMonitor)
         if (_isNotInPubCache(uri)) uri,
 
       // We need to check the .packages file too since it is not used in compilation.
diff --git a/packages/flutter_tools/lib/src/runner/flutter_command.dart b/packages/flutter_tools/lib/src/runner/flutter_command.dart
index a04e4029241..0d81d6fb8f3 100644
--- a/packages/flutter_tools/lib/src/runner/flutter_command.dart
+++ b/packages/flutter_tools/lib/src/runner/flutter_command.dart
@@ -445,7 +445,7 @@ abstract class FlutterCommand extends Command<void> {
             : null;
     if (argParser.options.containsKey(FlutterOptions.kEnableExperiment) &&
         argResults[FlutterOptions.kEnableExperiment] != null) {
-      for (String expFlag in stringsArg(FlutterOptions.kEnableExperiment)) {
+      for (final String expFlag in stringsArg(FlutterOptions.kEnableExperiment)) {
         final String flag = '--enable-experiment=' + expFlag;
         if (extraFrontEndOptions != null) {
           extraFrontEndOptions += ',' + flag;
@@ -743,7 +743,7 @@ mixin DeviceBasedDevelopmentArtifacts on FlutterCommand {
     final Set<DevelopmentArtifact> artifacts = <DevelopmentArtifact>{
       DevelopmentArtifact.universal,
     };
-    for (Device device in devices) {
+    for (final Device device in devices) {
       final TargetPlatform targetPlatform = await device.targetPlatform;
       final DevelopmentArtifact developmentArtifact = _artifactFromTargetPlatform(targetPlatform);
       if (developmentArtifact != null) {
diff --git a/packages/flutter_tools/lib/src/runner/flutter_command_runner.dart b/packages/flutter_tools/lib/src/runner/flutter_command_runner.dart
index ca6d67214d2..7731bd02298 100644
--- a/packages/flutter_tools/lib/src/runner/flutter_command_runner.dart
+++ b/packages/flutter_tools/lib/src/runner/flutter_command_runner.dart
@@ -206,7 +206,7 @@ class FlutterCommandRunner extends CommandRunner<void> {
       }
 
       Command<void> command = commands[error.commands.first];
-      for (String commandName in error.commands.skip(1)) {
+      for (final String commandName in error.commands.skip(1)) {
         command = command.subcommands[commandName];
       }
 
@@ -386,7 +386,7 @@ class FlutterCommandRunner extends CommandRunner<void> {
     tmpBasename = tmpBasename.substring(tmpBasename.indexOf('_') + 1);
     // Strip suffix for various archs.
     final List<String> suffixes = <String>['_arm', '_arm64', '_x86', '_x64'];
-    for (String suffix in suffixes) {
+    for (final String suffix in suffixes) {
       tmpBasename = tmpBasename.replaceFirst(RegExp('$suffix\$'), '');
     }
     return 'host_' + tmpBasename;
diff --git a/packages/flutter_tools/lib/src/template.dart b/packages/flutter_tools/lib/src/template.dart
index f47f450f984..e37fdddc501 100644
--- a/packages/flutter_tools/lib/src/template.dart
+++ b/packages/flutter_tools/lib/src/template.dart
@@ -33,7 +33,7 @@ class Template {
 
     final List<FileSystemEntity> templateFiles = templateSource.listSync(recursive: true);
 
-    for (FileSystemEntity entity in templateFiles) {
+    for (final FileSystemEntity entity in templateFiles) {
       if (entity is! File) {
         // We are only interesting in template *file* URIs.
         continue;
diff --git a/packages/flutter_tools/lib/src/test/coverage_collector.dart b/packages/flutter_tools/lib/src/test/coverage_collector.dart
index b9dad7274b8..2d8e6a8e906 100644
--- a/packages/flutter_tools/lib/src/test/coverage_collector.dart
+++ b/packages/flutter_tools/lib/src/test/coverage_collector.dart
@@ -188,7 +188,7 @@ Future<Map<String, dynamic>> collect(Uri serviceUri, bool Function(String) libra
 Future<Map<String, dynamic>> _getAllCoverage(VMService service, bool Function(String) libraryPredicate) async {
   await service.getVM();
   final List<Map<String, dynamic>> coverage = <Map<String, dynamic>>[];
-  for (Isolate isolateRef in service.vm.isolates) {
+  for (final Isolate isolateRef in service.vm.isolates) {
     await isolateRef.load();
     final Map<String, dynamic> scriptList = await isolateRef.invokeRpcRaw('getScripts', params: <String, dynamic>{'isolateId': isolateRef.id});
     final List<Future<void>> futures = <Future<void>>[];
@@ -204,7 +204,7 @@ Future<Map<String, dynamic>> _getAllCoverage(VMService service, bool Function(St
     if (scriptList['scripts'] == null) {
       continue;
     }
-    for (Map<String, dynamic> script in scriptList['scripts']) {
+    for (final Map<String, dynamic> script in scriptList['scripts']) {
       if (!libraryPredicate(script['uri'] as String)) {
         continue;
       }
@@ -243,9 +243,9 @@ void _buildCoverageMap(
   List<Map<String, dynamic>> coverage,
 ) {
   final Map<String, Map<int, int>> hitMaps = <String, Map<int, int>>{};
-  for (String scriptId in scripts.keys) {
+  for (final String scriptId in scripts.keys) {
     final Map<String, dynamic> sourceReport = sourceReports[scriptId];
-    for (Map<String, dynamic> range in sourceReport['ranges']) {
+    for (final Map<String, dynamic> range in sourceReport['ranges']) {
       final Map<String, dynamic> coverage = castStringKeyedMap(range['coverage']);
       // Coverage reports may sometimes be null for a Script.
       if (coverage == null) {
@@ -264,14 +264,14 @@ void _buildCoverageMap(
         continue;
       }
       if (hits != null) {
-        for (int hit in hits) {
+        for (final int hit in hits) {
           final int line = _lineAndColumn(hit, tokenPositions)[0];
           final int current = hitMap[line] ?? 0;
           hitMap[line] = current + 1;
         }
       }
       if (misses != null) {
-        for (int miss in misses) {
+        for (final int miss in misses) {
           final int line = _lineAndColumn(miss, tokenPositions)[0];
           hitMap[line] ??= 0;
         }
diff --git a/packages/flutter_tools/lib/src/test/flutter_platform.dart b/packages/flutter_tools/lib/src/test/flutter_platform.dart
index 8b73b578ed3..c47af1efc3b 100644
--- a/packages/flutter_tools/lib/src/test/flutter_platform.dart
+++ b/packages/flutter_tools/lib/src/test/flutter_platform.dart
@@ -678,7 +678,7 @@ class FlutterPlatform extends PlatformPlugin {
     } finally {
       globals.printTrace('test $ourTestCount: cleaning up...');
       // Finalizers are treated like a stack; run them in reverse order.
-      for (Finalizer finalizer in finalizers.reversed) {
+      for (final Finalizer finalizer in finalizers.reversed) {
         try {
           await finalizer();
         } catch (error, stack) {
@@ -850,7 +850,7 @@ class FlutterPlatform extends PlatformPlugin {
     void reportObservatoryUri(Uri uri),
   }) {
     const String observatoryString = 'Observatory listening on ';
-    for (Stream<List<int>> stream in <Stream<List<int>>>[
+    for (final Stream<List<int>> stream in <Stream<List<int>>>[
       process.stderr,
       process.stdout,
     ]) {
diff --git a/packages/flutter_tools/lib/src/test/flutter_web_platform.dart b/packages/flutter_tools/lib/src/test/flutter_web_platform.dart
index 7aa705b0555..c638f67f0ad 100644
--- a/packages/flutter_tools/lib/src/test/flutter_web_platform.dart
+++ b/packages/flutter_tools/lib/src/test/flutter_web_platform.dart
@@ -440,7 +440,7 @@ class PathHandler {
   /// the longest matching prefix wins.
   void add(String path, shelf.Handler handler) {
     _Node node = _paths;
-    for (String component in p.url.split(path)) {
+    for (final String component in p.url.split(path)) {
       node = node.children.putIfAbsent(component, () => _Node());
     }
     node.handler = handler;
@@ -489,7 +489,7 @@ class BrowserManager {
     // Start this canceled because we don't want it to start ticking until we
     // get some response from the iframe.
     _timer = RestartableTimer(const Duration(seconds: 3), () {
-      for (RunnerSuiteController controller in _controllers) {
+      for (final RunnerSuiteController controller in _controllers) {
         controller.setDebugging(true);
       }
     })
@@ -503,7 +503,7 @@ class BrowserManager {
           if (!_closed) {
             _timer.reset();
           }
-          for (RunnerSuiteController controller in _controllers) {
+          for (final RunnerSuiteController controller in _controllers) {
             controller.setDebugging(false);
           }
 
@@ -933,7 +933,7 @@ void main() async {
     .transform<String>(utf8.decoder)
     .transform<String>(const LineSplitter())
     .map<Object>(jsonDecode);
-  await for (Object command in commands) {
+  await for (final Object command in commands) {
     if (command is Map<String, dynamic>) {
       File imageFile = File(command['imageFile']);
       Uri goldenKey = Uri.parse(command['key']);
diff --git a/packages/flutter_tools/lib/src/test/runner.dart b/packages/flutter_tools/lib/src/test/runner.dart
index 593603df7f5..490cf504282 100644
--- a/packages/flutter_tools/lib/src/test/runner.dart
+++ b/packages/flutter_tools/lib/src/test/runner.dart
@@ -61,9 +61,9 @@ Future<int> runTests(
     else
       ...<String>['-r', 'compact'],
     '--concurrency=$concurrency',
-    for (String name in names)
+    for (final String name in names)
       ...<String>['--name', name],
-    for (String plainName in plainNames)
+    for (final String plainName in plainNames)
       ...<String>['--plain-name', plainName],
     '--test-randomize-ordering-seed=$randomSeed',
   ];
diff --git a/packages/flutter_tools/lib/src/tracing.dart b/packages/flutter_tools/lib/src/tracing.dart
index 623a10d65af..020d06816a7 100644
--- a/packages/flutter_tools/lib/src/tracing.dart
+++ b/packages/flutter_tools/lib/src/tracing.dart
@@ -51,7 +51,7 @@ class Tracing {
           }
         });
         bool done = false;
-        for (FlutterView view in vmService.vm.views) {
+        for (final FlutterView view in vmService.vm.views) {
           if (await view.uiIsolate.flutterAlreadyPaintedFirstUsefulFrame()) {
             done = true;
             break;
diff --git a/packages/flutter_tools/lib/src/vmservice.dart b/packages/flutter_tools/lib/src/vmservice.dart
index 9d0450ecb52..99adc781dc3 100644
--- a/packages/flutter_tools/lib/src/vmservice.dart
+++ b/packages/flutter_tools/lib/src/vmservice.dart
@@ -856,7 +856,7 @@ class VM extends ServiceObjectOwner {
   void _removeDeadIsolates(List<Isolate> newIsolates) {
     // Build a set of new isolates.
     final Set<String> newIsolateSet = <String>{};
-    for (Isolate iso in newIsolates) {
+    for (final Isolate iso in newIsolates) {
       newIsolateSet.add(iso.id);
     }
 
diff --git a/packages/flutter_tools/lib/src/vscode/vscode.dart b/packages/flutter_tools/lib/src/vscode/vscode.dart
index 64104931130..b11004656b1 100644
--- a/packages/flutter_tools/lib/src/vscode/vscode.dart
+++ b/packages/flutter_tools/lib/src/vscode/vscode.dart
@@ -204,7 +204,7 @@ class VsCode {
 
     final List<VsCode> results = <VsCode>[];
 
-    for (_VsCodeInstallLocation searchLocation in searchLocations) {
+    for (final _VsCodeInstallLocation searchLocation in searchLocations) {
       if (globals.fs.isDirectorySync(searchLocation.installPath)) {
         final String extensionDirectory =
             globals.fs.path.join(homeDirPath, searchLocation.extensionsFolder, 'extensions');
diff --git a/packages/flutter_tools/lib/src/web/compile.dart b/packages/flutter_tools/lib/src/web/compile.dart
index 8f024d240e9..c0620314ee6 100644
--- a/packages/flutter_tools/lib/src/web/compile.dart
+++ b/packages/flutter_tools/lib/src/web/compile.dart
@@ -53,7 +53,7 @@ Future<void> buildWeb(
       },
     ));
     if (!result.success) {
-      for (ExceptionMeasurement measurement in result.exceptions.values) {
+      for (final ExceptionMeasurement measurement in result.exceptions.values) {
         globals.printError('Target ${measurement.target} failed: ${measurement.exception}',
           stackTrace: measurement.fatal
             ? measurement.stackTrace
diff --git a/packages/flutter_tools/lib/src/web/devfs_web.dart b/packages/flutter_tools/lib/src/web/devfs_web.dart
index c28815b4aff..e24ef5ec8b5 100644
--- a/packages/flutter_tools/lib/src/web/devfs_web.dart
+++ b/packages/flutter_tools/lib/src/web/devfs_web.dart
@@ -177,7 +177,7 @@ class WebAssetServer {
     final Uint8List codeBytes = codeFile.readAsBytesSync();
     final Uint8List sourcemapBytes = sourcemapFile.readAsBytesSync();
     final Map<String, dynamic> manifest = castStringKeyedMap(json.decode(manifestFile.readAsStringSync()));
-    for (String filePath in manifest.keys) {
+    for (final String filePath in manifest.keys) {
       if (filePath == null) {
         globals.printTrace('Invalid manfiest file: $filePath');
         continue;
diff --git a/packages/flutter_tools/lib/src/windows/windows_device.dart b/packages/flutter_tools/lib/src/windows/windows_device.dart
index 1161d6d0c62..f7f0b65d0e0 100644
--- a/packages/flutter_tools/lib/src/windows/windows_device.dart
+++ b/packages/flutter_tools/lib/src/windows/windows_device.dart
@@ -93,7 +93,7 @@ List<String> runningProcess(String processName) {
   if (result.exitCode != 0) {
     return null;
   }
-  for (String rawProcess in result.stdout.split('\n')) {
+  for (final String rawProcess in result.stdout.split('\n')) {
     final String process = rawProcess.trim();
     if (!process.contains(processName)) {
       continue;
diff --git a/packages/flutter_tools/test/commands.shard/hermetic/build_web_test.dart b/packages/flutter_tools/test/commands.shard/hermetic/build_web_test.dart
index 52922ca1538..7565fa3a4d6 100644
--- a/packages/flutter_tools/test/commands.shard/hermetic/build_web_test.dart
+++ b/packages/flutter_tools/test/commands.shard/hermetic/build_web_test.dart
@@ -106,7 +106,7 @@ void main() {
       globals.fs.path.join('bin', 'cache', 'dart-sdk', 'bin', 'dart'),
       globals.fs.path.join('bin', 'cache', 'dart-sdk '),
     ];
-    for (String dependency in dependencies) {
+    for (final String dependency in dependencies) {
       globals.fs.file(dependency).createSync(recursive: true);
     }
 
diff --git a/packages/flutter_tools/test/commands.shard/hermetic/create_usage_test.dart b/packages/flutter_tools/test/commands.shard/hermetic/create_usage_test.dart
index dc775570262..a9db5b9422b 100644
--- a/packages/flutter_tools/test/commands.shard/hermetic/create_usage_test.dart
+++ b/packages/flutter_tools/test/commands.shard/hermetic/create_usage_test.dart
@@ -31,7 +31,7 @@ void main() {
           globals.fs.path.join('usr', 'local', 'bin', 'adb'),
           globals.fs.path.join('Android', 'platform-tools', 'adb.exe'),
         ];
-        for (String path in paths) {
+        for (final String path in paths) {
           globals.fs.file(path).createSync(recursive: true);
         }
       }, overrides: <Type, Generator>{
diff --git a/packages/flutter_tools/test/commands.shard/hermetic/doctor_test.dart b/packages/flutter_tools/test/commands.shard/hermetic/doctor_test.dart
index 5b3e077dbac..a6ec89b8210 100644
--- a/packages/flutter_tools/test/commands.shard/hermetic/doctor_test.dart
+++ b/packages/flutter_tools/test/commands.shard/hermetic/doctor_test.dart
@@ -499,11 +499,11 @@ void main() {
 
       expect(await FlutterValidatorDoctor().diagnose(verbose: false), isTrue);
       final List<String> statusLines = testLogger.statusText.split('\n');
-      for (String msg in userMessages.flutterBinariesDoNotRun.split('\n')) {
+      for (final String msg in userMessages.flutterBinariesDoNotRun.split('\n')) {
         expect(statusLines, contains(contains(msg)));
       }
       if (globals.platform.isLinux) {
-        for (String msg in userMessages.flutterBinariesLinuxRepairCommands.split('\n')) {
+        for (final String msg in userMessages.flutterBinariesLinuxRepairCommands.split('\n')) {
           expect(statusLines, contains(contains(msg)));
         }
       }
diff --git a/packages/flutter_tools/test/commands.shard/hermetic/ide_config_test.dart b/packages/flutter_tools/test/commands.shard/hermetic/ide_config_test.dart
index 3e228685921..adda297cf66 100644
--- a/packages/flutter_tools/test/commands.shard/hermetic/ide_config_test.dart
+++ b/packages/flutter_tools/test/commands.shard/hermetic/ide_config_test.dart
@@ -29,7 +29,7 @@ void main() {
           return relativePath;
         }).toList();
       final Map<String, String> contents = <String, String>{};
-      for (String path in paths) {
+      for (final String path in paths) {
         final String absPath = globals.fs.path.join(tempPath, path);
         if (globals.fs.isDirectorySync(absPath)) {
           contents[path] = 'dir';
@@ -56,12 +56,12 @@ void main() {
     }
 
     void _populateDir(Map<String, String> manifest) {
-      for (String key in manifest.keys) {
+      for (final String key in manifest.keys) {
         if (manifest[key] == 'dir') {
           tempDir.childDirectory(key)..createSync(recursive: true);
         }
       }
-      for (String key in manifest.keys) {
+      for (final String key in manifest.keys) {
         if (manifest[key] != 'dir') {
           tempDir.childFile(key)
             ..createSync(recursive: true)
@@ -90,7 +90,7 @@ void main() {
         ...args,
       ]);
 
-      for (String path in expectedContents.keys) {
+      for (final String path in expectedContents.keys) {
         final String absPath = globals.fs.path.join(tempDir.absolute.path, path);
         expect(_fileOrDirectoryExists(globals.fs.path.join(dir.path, path)), true,
             reason: "$path doesn't exist");
@@ -99,7 +99,7 @@ void main() {
               reason: "$path contents don't match");
         }
       }
-      for (String path in unexpectedPaths) {
+      for (final String path in unexpectedPaths) {
         expect(_fileOrDirectoryExists(globals.fs.path.join(dir.path, path)), false, reason: '$path exists');
       }
     }
diff --git a/packages/flutter_tools/test/commands.shard/permeable/analyze_once_test.dart b/packages/flutter_tools/test/commands.shard/permeable/analyze_once_test.dart
index 9ff81a88efc..5d988d012c0 100644
--- a/packages/flutter_tools/test/commands.shard/permeable/analyze_once_test.dart
+++ b/packages/flutter_tools/test/commands.shard/permeable/analyze_once_test.dart
@@ -258,7 +258,7 @@ void assertContains(String text, List<String> patterns) {
   if (patterns == null) {
     expect(text, isEmpty);
   } else {
-    for (String pattern in patterns) {
+    for (final String pattern in patterns) {
       expect(text, contains(pattern));
     }
   }
diff --git a/packages/flutter_tools/test/commands.shard/permeable/create_test.dart b/packages/flutter_tools/test/commands.shard/permeable/create_test.dart
index b1d284eca2d..049bec84687 100644
--- a/packages/flutter_tools/test/commands.shard/permeable/create_test.dart
+++ b/packages/flutter_tools/test/commands.shard/permeable/create_test.dart
@@ -645,7 +645,7 @@ void main() {
 
     expect(actualContents.contains('flutter_test.dart'), true);
 
-    for (FileSystemEntity file in projectDir.listSync(recursive: true)) {
+    for (final FileSystemEntity file in projectDir.listSync(recursive: true)) {
       if (file is File && file.path.endsWith('.dart')) {
         final String original = file.readAsStringSync();
 
@@ -737,7 +737,7 @@ void main() {
     expectExists('lib/main.dart');
     expectExists('test/widget_test.dart');
 
-    for (FileSystemEntity file in projectDir.listSync(recursive: true)) {
+    for (final FileSystemEntity file in projectDir.listSync(recursive: true)) {
       if (file is File && file.path.endsWith('.dart')) {
         final String original = file.readAsStringSync();
 
@@ -1227,10 +1227,10 @@ Future<void> _createProject(
   }
 
   final List<String> failures = <String>[
-    for (String path in expectedPaths)
+    for (final String path in expectedPaths)
       if (!pathExists(path))
         'Path "$path" does not exist.',
-    for (String path in unexpectedPaths)
+    for (final String path in unexpectedPaths)
       if (pathExists(path))
         'Path "$path" exists when it shouldn\'t.',
   ];
diff --git a/packages/flutter_tools/test/commands.shard/permeable/packages_test.dart b/packages/flutter_tools/test/commands.shard/permeable/packages_test.dart
index 657b5808a1a..b48c9d57e3f 100644
--- a/packages/flutter_tools/test/commands.shard/permeable/packages_test.dart
+++ b/packages/flutter_tools/test/commands.shard/permeable/packages_test.dart
@@ -146,7 +146,7 @@ void main() {
     };
 
     void expectDependenciesResolved(String projectPath) {
-      for (String output in pubOutput) {
+      for (final String output in pubOutput) {
         expectExists(projectPath, output);
       }
     }
@@ -193,7 +193,7 @@ void main() {
         modulePluginRegistrants,
         pluginWitnesses,
       ].expand<String>((List<String> list) => list);
-      for (String path in allFiles) {
+      for (final String path in allFiles) {
         final File file = globals.fs.file(globals.fs.path.join(projectPath, path));
         if (file.existsSync()) {
           file.deleteSync();
diff --git a/packages/flutter_tools/test/general.shard/android/android_sdk_test.dart b/packages/flutter_tools/test/general.shard/android/android_sdk_test.dart
index 736531b80c9..b1cfd66585c 100644
--- a/packages/flutter_tools/test/general.shard/android/android_sdk_test.dart
+++ b/packages/flutter_tools/test/general.shard/android/android_sdk_test.dart
@@ -201,7 +201,7 @@ void main() {
         });
       });
 
-      for (String os in <String>['linux', 'macos']) {
+      for (final String os in <String>['linux', 'macos']) {
         testUsingContext('detection on $os (no ndk available)', () {
           sdkDir = MockAndroidSdk.createSdkDirectory(withAndroidN: true);
           globals.config.setValue('android-sdk', sdkDir.path);
diff --git a/packages/flutter_tools/test/general.shard/android/gradle_test.dart b/packages/flutter_tools/test/general.shard/android/gradle_test.dart
index 17cb6512da0..83f69c70568 100644
--- a/packages/flutter_tools/test/general.shard/android/gradle_test.dart
+++ b/packages/flutter_tools/test/general.shard/android/gradle_test.dart
@@ -441,10 +441,10 @@ void main() {
         'See https://goo.gl/CP92wY for more information on the problem and how to fix it.',
         'This warning prints for all Android build failures. The real root cause of the error may be unrelated.',
       ];
-      for (String m in nonMatchingLines) {
+      for (final String m in nonMatchingLines) {
         expect(androidXPluginWarningRegex.hasMatch(m), isFalse);
       }
-      for (String m in matchingLines) {
+      for (final String m in matchingLines) {
         expect(androidXPluginWarningRegex.hasMatch(m), isTrue);
       }
     });
diff --git a/packages/flutter_tools/test/general.shard/asset_bundle_package_fonts_test.dart b/packages/flutter_tools/test/general.shard/asset_bundle_package_fonts_test.dart
index 222c96f2120..6ce082395bb 100644
--- a/packages/flutter_tools/test/general.shard/asset_bundle_package_fonts_test.dart
+++ b/packages/flutter_tools/test/general.shard/asset_bundle_package_fonts_test.dart
@@ -70,8 +70,8 @@ $fontsSection
     final AssetBundle bundle = AssetBundleFactory.instance.createBundle();
     await bundle.build(manifestPath: 'pubspec.yaml');
 
-    for (String packageName in packages) {
-      for (String packageFont in packageFonts) {
+    for (final String packageName in packages) {
+      for (final String packageFont in packageFonts) {
         final String entryKey = 'packages/$packageName/$packageFont';
         expect(bundle.entries.containsKey(entryKey), true);
         expect(
@@ -80,7 +80,7 @@ $fontsSection
         );
       }
 
-      for (String localFont in localFonts) {
+      for (final String localFont in localFonts) {
         expect(bundle.entries.containsKey(localFont), true);
         expect(
           utf8.decode(await bundle.entries[localFont].contentsAsBytes()),
diff --git a/packages/flutter_tools/test/general.shard/asset_bundle_package_test.dart b/packages/flutter_tools/test/general.shard/asset_bundle_package_test.dart
index 25e208982fc..e75dde645e5 100644
--- a/packages/flutter_tools/test/general.shard/asset_bundle_package_test.dart
+++ b/packages/flutter_tools/test/general.shard/asset_bundle_package_test.dart
@@ -38,7 +38,7 @@ flutter:
      assets:
 ''');
 
-      for (String asset in assets) {
+      for (final String asset in assets) {
         buffer.write('''
        - $asset
 ''');
@@ -75,8 +75,8 @@ $assetsSection
     final AssetBundle bundle = AssetBundleFactory.instance.createBundle();
     await bundle.build(manifestPath: 'pubspec.yaml');
 
-    for (String packageName in packages) {
-      for (String asset in assets) {
+    for (final String packageName in packages) {
+      for (final String asset in assets) {
         final String entryKey = Uri.encodeFull('packages/$packageName/$asset');
         expect(bundle.entries.containsKey(entryKey), true, reason: 'Cannot find key on bundle: $entryKey');
         expect(
@@ -93,7 +93,7 @@ $assetsSection
   }
 
   void writeAssets(String path, List<String> assets) {
-    for (String asset in assets) {
+    for (final String asset in assets) {
       final String fullPath = fixPath(globals.fs.path.join(path, asset));
 
       globals.fs.file(fullPath)
diff --git a/packages/flutter_tools/test/general.shard/asset_bundle_variant_test.dart b/packages/flutter_tools/test/general.shard/asset_bundle_variant_test.dart
index dcd7627c0cd..5fa9fda49f6 100644
--- a/packages/flutter_tools/test/general.shard/asset_bundle_variant_test.dart
+++ b/packages/flutter_tools/test/general.shard/asset_bundle_variant_test.dart
@@ -65,7 +65,7 @@ flutter:
         'a/b/c/var2/foo',
         'a/b/c/var3/foo',
       ];
-      for (String asset in assets) {
+      for (final String asset in assets) {
         globals.fs.file(fixPath(asset))
           ..createSync(recursive: true)
           ..writeAsStringSync(asset);
@@ -75,7 +75,7 @@ flutter:
       await bundle.build(manifestPath: 'pubspec.yaml');
 
       // The main asset file, /a/b/c/foo, and its variants exist.
-      for (String asset in assets) {
+      for (final String asset in assets) {
         expect(bundle.entries.containsKey(asset), true);
         expect(utf8.decode(await bundle.entries[asset].contentsAsBytes()), asset);
       }
@@ -87,7 +87,7 @@ flutter:
       // Now the main asset file, /a/b/c/foo, does not exist. This is OK because
       // the /a/b/c/*/foo variants do exist.
       expect(bundle.entries.containsKey('a/b/c/foo'), false);
-      for (String asset in assets.skip(1)) {
+      for (final String asset in assets.skip(1)) {
         expect(bundle.entries.containsKey(asset), true);
         expect(utf8.decode(await bundle.entries[asset].contentsAsBytes()), asset);
       }
diff --git a/packages/flutter_tools/test/general.shard/base/build_test.dart b/packages/flutter_tools/test/general.shard/base/build_test.dart
index 62c4c18b739..450e818198d 100644
--- a/packages/flutter_tools/test/general.shard/base/build_test.dart
+++ b/packages/flutter_tools/test/general.shard/base/build_test.dart
@@ -248,7 +248,7 @@ void main() {
       when(mockXcode.sdkLocation(any)).thenAnswer((_) => Future<String>.value(kSDKPath));
 
       bufferLogger = BufferLogger();
-      for (BuildMode mode in BuildMode.values) {
+      for (final BuildMode mode in BuildMode.values) {
         when(mockArtifacts.getArtifactPath(Artifact.snapshotDart,
             platform: anyNamed('platform'), mode: mode)).thenReturn(kSnapshotDart);
       }
diff --git a/packages/flutter_tools/test/general.shard/base/logger_test.dart b/packages/flutter_tools/test/general.shard/base/logger_test.dart
index b30772bcd60..189464caacd 100644
--- a/packages/flutter_tools/test/general.shard/base/logger_test.dart
+++ b/packages/flutter_tools/test/general.shard/base/logger_test.dart
@@ -103,7 +103,7 @@ void main() {
       } while (doThis());
     }
 
-    for (String testOs in testPlatforms) {
+    for (final String testOs in testPlatforms) {
       testUsingContext('AnsiSpinner works for $testOs (1)', () async {
         bool done = false;
         mockStopwatch = FakeStopwatch();
@@ -255,7 +255,7 @@ void main() {
           expect(outputStdout().join('\n'), contains('This is taking an unexpectedly long time.'));
 
           // Test that the number of '\b' is correct.
-          for (String line in outputStdout()) {
+          for (final String line in outputStdout()) {
             int currLength = 0;
             for (int i = 0; i < line.length; i += 1) {
               currLength += line[i] == '\b' ? -1 : 1;
diff --git a/packages/flutter_tools/test/general.shard/base/terminal_test.dart b/packages/flutter_tools/test/general.shard/base/terminal_test.dart
index f6bc6755236..ff62a6f9056 100644
--- a/packages/flutter_tools/test/general.shard/base/terminal_test.dart
+++ b/packages/flutter_tools/test/general.shard/base/terminal_test.dart
@@ -40,7 +40,7 @@ void main() {
     });
 
     testUsingContext('adding colors works', () {
-      for (TerminalColor color in TerminalColor.values) {
+      for (final TerminalColor color in TerminalColor.values) {
         expect(
           terminal.color('output', color),
           equals('${AnsiTerminal.colorCode(color)}output${AnsiTerminal.resetColor}'),
diff --git a/packages/flutter_tools/test/general.shard/build_system/targets/dart_test.dart b/packages/flutter_tools/test/general.shard/build_system/targets/dart_test.dart
index b83b51b370f..9d83b2edc5a 100644
--- a/packages/flutter_tools/test/general.shard/build_system/targets/dart_test.dart
+++ b/packages/flutter_tools/test/general.shard/build_system/targets/dart_test.dart
@@ -96,7 +96,7 @@ flutter_tools:lib/''');
         globals.fs.path.join('packages', 'flutter_tools', 'lib', 'src', 'build_system', 'targets', 'dart.dart'),
         globals.fs.path.join('packages', 'flutter_tools', 'lib', 'src', 'build_system', 'targets', 'ios.dart'),
       ];
-      for (String path in paths) {
+      for (final String path in paths) {
         globals.fs.file(path).createSync(recursive: true);
       }
     }, overrides: <Type, Generator>{
diff --git a/packages/flutter_tools/test/general.shard/build_system/targets/macos_test.dart b/packages/flutter_tools/test/general.shard/build_system/targets/macos_test.dart
index cd09381e25f..56f7b3d1fc8 100644
--- a/packages/flutter_tools/test/general.shard/build_system/targets/macos_test.dart
+++ b/packages/flutter_tools/test/general.shard/build_system/targets/macos_test.dart
@@ -82,7 +82,7 @@ void main() {
   });
 
   test('Copies files to correct cache directory', () => testbed.run(() async {
-    for (File input in inputs) {
+    for (final File input in inputs) {
       input.createSync(recursive: true);
     }
     // Create output directory so we can test that it is deleted.
@@ -100,7 +100,7 @@ void main() {
       expect(target.existsSync(), false);
       target.createSync(recursive: true);
 
-      for (FileSystemEntity entity in source.listSync(recursive: true)) {
+      for (final FileSystemEntity entity in source.listSync(recursive: true)) {
         if (entity is File) {
           final String relative = globals.fs.path.relative(entity.path, from: source.path);
           final String destination = globals.fs.path.join(target.path, relative);
@@ -115,7 +115,7 @@ void main() {
     await const DebugUnpackMacOS().build(environment);
 
     expect(globals.fs.directory('$_kOutputPrefix').existsSync(), true);
-    for (File file in inputs) {
+    for (final File file in inputs) {
       expect(globals.fs.file(file.path.replaceFirst(_kInputPrefix, _kOutputPrefix)).existsSync(), true);
     }
   }));
diff --git a/packages/flutter_tools/test/general.shard/dart/sdk_validation_test.dart b/packages/flutter_tools/test/general.shard/dart/sdk_validation_test.dart
index 9d864c142e9..e91b4cc6b10 100644
--- a/packages/flutter_tools/test/general.shard/dart/sdk_validation_test.dart
+++ b/packages/flutter_tools/test/general.shard/dart/sdk_validation_test.dart
@@ -64,7 +64,7 @@ Future<int> analyze(AnalysisServer server) async {
   int errorCount = 0;
   final Future<bool> onDone = server.onAnalyzing.where((bool analyzing) => analyzing == false).first;
   server.onErrors.listen((FileAnalysisErrors result) {
-    for (AnalysisError error in result.errors) {
+    for (final AnalysisError error in result.errors) {
       print(error.toString().trim());
     }
     errorCount += result.errors.length;
diff --git a/packages/flutter_tools/test/general.shard/forbidden_imports_test.dart b/packages/flutter_tools/test/general.shard/forbidden_imports_test.dart
index dce6b558fa4..eb771ab6034 100644
--- a/packages/flutter_tools/test/general.shard/forbidden_imports_test.dart
+++ b/packages/flutter_tools/test/general.shard/forbidden_imports_test.dart
@@ -22,8 +22,8 @@ void main() {
       .where(_isDartFile)
       .where(_isNotSkipped)
       .map(_asFile);
-    for (File file in files) {
-      for (String line in file.readAsLinesSync()) {
+    for (final File file in files) {
+      for (final String line in file.readAsLinesSync()) {
         if (line.startsWith(RegExp(r'import.*package:'))) {
           continue;
         }
@@ -47,8 +47,8 @@ void main() {
       .where(_isDartFile)
       .where(_isNotSkipped)
       .map(_asFile);
-    for (File file in files) {
-      for (String line in file.readAsLinesSync()) {
+    for (final File file in files) {
+      for (final String line in file.readAsLinesSync()) {
         if (line.startsWith(RegExp(r'import.*globals.dart'))
          && !line.contains(r'as globals')) {
           final String relativePath = globals.fs.path.relative(file.path, from:flutterTools);
@@ -65,14 +65,14 @@ void main() {
     ];
     bool _isNotWhitelisted(FileSystemEntity entity) => whitelistedPaths.every((String path) => path != entity.path);
 
-    for (String dirName in <String>['lib', 'bin']) {
+    for (final String dirName in <String>['lib', 'bin']) {
       final Iterable<File> files = globals.fs.directory(globals.fs.path.join(flutterTools, dirName))
         .listSync(recursive: true)
         .where(_isDartFile)
         .where(_isNotWhitelisted)
         .map(_asFile);
-      for (File file in files) {
-        for (String line in file.readAsLinesSync()) {
+      for (final File file in files) {
+        for (final String line in file.readAsLinesSync()) {
           if (line.startsWith(RegExp(r'import.*dart:io')) &&
               !line.contains('ignore: dart_io_import')) {
             final String relativePath = globals.fs.path.relative(file.path, from:flutterTools);
@@ -92,14 +92,14 @@ void main() {
     ];
     bool _isNotWhitelisted(FileSystemEntity entity) => whitelistedPaths.every((String path) => path != entity.path);
 
-    for (String dirName in <String>['lib']) {
+    for (final String dirName in <String>['lib']) {
       final Iterable<File> files = globals.fs.directory(globals.fs.path.join(flutterTools, dirName))
         .listSync(recursive: true)
         .where(_isDartFile)
         .where(_isNotWhitelisted)
         .map(_asFile);
-      for (File file in files) {
-        for (String line in file.readAsLinesSync()) {
+      for (final File file in files) {
+        for (final String line in file.readAsLinesSync()) {
           if (line.startsWith(RegExp(r'import.*package:test_api')) &&
               !line.contains('ignore: test_api_import')) {
             final String relativePath = globals.fs.path.relative(file.path, from:flutterTools);
@@ -112,14 +112,14 @@ void main() {
 
   test('no unauthorized imports of package:path', () {
     final String whitelistedPath = globals.fs.path.join(flutterTools, 'lib', 'src', 'build_runner', 'web_compilation_delegate.dart');
-    for (String dirName in <String>['lib', 'bin', 'test']) {
+    for (final String dirName in <String>['lib', 'bin', 'test']) {
       final Iterable<File> files = globals.fs.directory(globals.fs.path.join(flutterTools, dirName))
         .listSync(recursive: true)
         .where(_isDartFile)
         .where((FileSystemEntity entity) => entity.path != whitelistedPath)
         .map(_asFile);
-      for (File file in files) {
-        for (String line in file.readAsLinesSync()) {
+      for (final File file in files) {
+        for (final String line in file.readAsLinesSync()) {
           if (line.startsWith(RegExp(r'import.*package:path/path.dart')) &&
               !line.contains('ignore: package_path_import')) {
             final String relativePath = globals.fs.path.relative(file.path, from:flutterTools);
@@ -137,14 +137,14 @@ void main() {
     ];
     bool _isNotWhitelisted(FileSystemEntity entity) => whitelistedPaths.every((String path) => path != entity.path);
 
-    for (String dirName in <String>['lib']) {
+    for (final String dirName in <String>['lib']) {
       final Iterable<File> files = globals.fs.directory(globals.fs.path.join(flutterTools, dirName))
         .listSync(recursive: true)
         .where(_isDartFile)
         .where(_isNotWhitelisted)
         .map(_asFile);
-      for (File file in files) {
-        for (String line in file.readAsLinesSync()) {
+      for (final File file in files) {
+        for (final String line in file.readAsLinesSync()) {
           if (line.startsWith(RegExp(r'import.*dart:convert')) &&
               !line.contains('ignore: dart_convert_import')) {
             final String relativePath = globals.fs.path.relative(file.path, from:flutterTools);
@@ -163,14 +163,14 @@ void main() {
     ];
     bool _isNotWhitelisted(FileSystemEntity entity) => whitelistedPaths.every((String path) => !entity.path.contains(path));
 
-    for (String dirName in <String>['lib']) {
+    for (final String dirName in <String>['lib']) {
       final Iterable<File> files = globals.fs.directory(globals.fs.path.join(flutterTools, dirName))
         .listSync(recursive: true)
         .where(_isDartFile)
         .where(_isNotWhitelisted)
         .map(_asFile);
-      for (File file in files) {
-        for (String line in file.readAsLinesSync()) {
+      for (final File file in files) {
+        for (final String line in file.readAsLinesSync()) {
           if (line.startsWith(RegExp(r'import.*package:build_runner_core/build_runner_core.dart')) ||
               line.startsWith(RegExp(r'import.*package:build_runner/build_runner.dart')) ||
               line.startsWith(RegExp(r'import.*package:build_config/build_config.dart')) ||
diff --git a/packages/flutter_tools/test/general.shard/fuchsia/fuchsia_device_test.dart b/packages/flutter_tools/test/general.shard/fuchsia/fuchsia_device_test.dart
index d5b4e58f851..3bc889f352e 100644
--- a/packages/flutter_tools/test/general.shard/fuchsia/fuchsia_device_test.dart
+++ b/packages/flutter_tools/test/general.shard/fuchsia/fuchsia_device_test.dart
@@ -337,7 +337,7 @@ void main() {
 
     Future<Uri> findUri(List<MockFlutterView> views, String expectedIsolateName) async {
       when(vm.views).thenReturn(views);
-      for (MockFlutterView view in views) {
+      for (final MockFlutterView view in views) {
         when(view.owner).thenReturn(vm);
       }
       final MockFuchsiaDevice fuchsiaDevice =
diff --git a/packages/flutter_tools/test/general.shard/ios/devices_test.dart b/packages/flutter_tools/test/general.shard/ios/devices_test.dart
index 4820ae29689..fbf7ff002dc 100644
--- a/packages/flutter_tools/test/general.shard/ios/devices_test.dart
+++ b/packages/flutter_tools/test/general.shard/ios/devices_test.dart
@@ -80,7 +80,7 @@ void main() {
       Platform: () => macPlatform,
     });
 
-    for (Platform platform in unsupportedPlatforms) {
+    for (final Platform platform in unsupportedPlatforms) {
       testUsingContext('throws UnsupportedError exception if instantiated on ${platform.operatingSystem}', () {
         expect(
           () { IOSDevice('device-123'); },
@@ -781,7 +781,7 @@ void main() {
     });
 
     final List<Platform> unsupportedPlatforms = <Platform>[linuxPlatform, windowsPlatform];
-    for (Platform platform in unsupportedPlatforms) {
+    for (final Platform platform in unsupportedPlatforms) {
       testUsingContext('throws Unsupported Operation exception on ${platform.operatingSystem}', () async {
         when(iMobileDevice.isInstalled).thenReturn(false);
         when(iMobileDevice.getAvailableDeviceIDs())
diff --git a/packages/flutter_tools/test/general.shard/plugins_test.dart b/packages/flutter_tools/test/general.shard/plugins_test.dart
index 7d2d8211149..30b44018738 100644
--- a/packages/flutter_tools/test/general.shard/plugins_test.dart
+++ b/packages/flutter_tools/test/general.shard/plugins_test.dart
@@ -208,7 +208,7 @@ flutter:
     pluginClass: UseNewEmbedding
 dependencies:
 ''');
-      for (String dependency in dependencies) {
+      for (final String dependency in dependencies) {
         pluginDirectory
           .childFile('pubspec.yaml')
           .writeAsStringSync('  $dependency:\n', mode: FileMode.append);
diff --git a/packages/flutter_tools/test/general.shard/project_file_invalidator_test.dart b/packages/flutter_tools/test/general.shard/project_file_invalidator_test.dart
index 3d251a5580d..d46e562966c 100644
--- a/packages/flutter_tools/test/general.shard/project_file_invalidator_test.dart
+++ b/packages/flutter_tools/test/general.shard/project_file_invalidator_test.dart
@@ -14,7 +14,7 @@ import '../src/common.dart';
 final DateTime inFuture = DateTime.now().add(const Duration(days: 100));
 
 void main() {
-  for (bool asyncScanning in <bool>[true, false]) {
+  for (final bool asyncScanning in <bool>[true, false]) {
     testWithoutContext('No last compile, asyncScanning: $asyncScanning', () async {
       final ProjectFileInvalidator projectFileInvalidator = ProjectFileInvalidator(
         fileSystem: MemoryFileSystem(),
diff --git a/packages/flutter_tools/test/general.shard/project_test.dart b/packages/flutter_tools/test/general.shard/project_test.dart
index d42a6172c3f..1fcdfe69d12 100644
--- a/packages/flutter_tools/test/general.shard/project_test.dart
+++ b/packages/flutter_tools/test/general.shard/project_test.dart
@@ -643,7 +643,7 @@ void testInMemory(String description, Future<void> testMethod()) {
 void transfer(FileSystemEntity entity, FileSystem target) {
   if (entity is Directory) {
     target.directory(entity.absolute.path).createSync(recursive: true);
-    for (FileSystemEntity child in entity.listSync()) {
+    for (final FileSystemEntity child in entity.listSync()) {
       transfer(child, target);
     }
   } else if (entity is File) {
diff --git a/packages/flutter_tools/test/general.shard/version_test.dart b/packages/flutter_tools/test/general.shard/version_test.dart
index bf68b530cac..41d77c03165 100644
--- a/packages/flutter_tools/test/general.shard/version_test.dart
+++ b/packages/flutter_tools/test/general.shard/version_test.dart
@@ -30,7 +30,7 @@ void main() {
     mockCache = MockCache();
   });
 
-  for (String channel in FlutterVersion.officialChannels) {
+  for (final String channel in FlutterVersion.officialChannels) {
     DateTime getChannelUpToDateVersion() {
       return _testClock.ago(FlutterVersion.versionAgeConsideredUpToDate(channel) ~/ 2);
     }
diff --git a/packages/flutter_tools/test/integration.shard/test_driver.dart b/packages/flutter_tools/test/integration.shard/test_driver.dart
index 8dc062f0eed..7fa4c91b4ba 100644
--- a/packages/flutter_tools/test/integration.shard/test_driver.dart
+++ b/packages/flutter_tools/test/integration.shard/test_driver.dart
@@ -319,7 +319,7 @@ abstract class FlutterTestDriver {
   }
 
   SourcePosition _lookupTokenPos(List<List<int>> table, int tokenPos) {
-    for (List<int> row in table) {
+    for (final List<int> row in table) {
       final int lineNumber = row[0];
       int index = 1;
 
diff --git a/packages/flutter_tools/test/src/fake_process_manager.dart b/packages/flutter_tools/test/src/fake_process_manager.dart
index 0e822fd02b7..1a1830ae346 100644
--- a/packages/flutter_tools/test/src/fake_process_manager.dart
+++ b/packages/flutter_tools/test/src/fake_process_manager.dart
@@ -105,7 +105,7 @@ class FakeCommand {
       if (environment == null) {
         return false;
       }
-      for (String key in environment.keys) {
+      for (final String key in environment.keys) {
         if (environment[key] != this.environment[key]) {
           return false;
         }
diff --git a/packages/flutter_tools/test/src/mocks.dart b/packages/flutter_tools/test/src/mocks.dart
index 95fdd64d656..5929c1cc4f1 100644
--- a/packages/flutter_tools/test/src/mocks.dart
+++ b/packages/flutter_tools/test/src/mocks.dart
@@ -399,7 +399,7 @@ class MemoryIOSink implements IOSink {
   @override
   void writeAll(Iterable<dynamic> objects, [ String separator = '' ]) {
     bool addSeparator = false;
-    for (dynamic object in objects) {
+    for (final dynamic object in objects) {
       if (addSeparator) {
         write(separator);
       }
diff --git a/packages/flutter_tools/test/src/testbed.dart b/packages/flutter_tools/test/src/testbed.dart
index 2022ebf2423..ab68e92f4b4 100644
--- a/packages/flutter_tools/test/src/testbed.dart
+++ b/packages/flutter_tools/test/src/testbed.dart
@@ -139,7 +139,7 @@ class Testbed {
             }
             await test();
             Cache.flutterRoot = originalFlutterRoot;
-            for (MapEntry<Timer, StackTrace> entry in timers.entries) {
+            for (final MapEntry<Timer, StackTrace> entry in timers.entries) {
               if (entry.key.isActive) {
                 throw StateError('A Timer was active at the end of a test: ${entry.value}');
               }
diff --git a/packages/fuchsia_remote_debug_protocol/examples/list_vms_and_flutter_views.dart b/packages/fuchsia_remote_debug_protocol/examples/list_vms_and_flutter_views.dart
index 13928727af1..9985da34385 100644
--- a/packages/fuchsia_remote_debug_protocol/examples/list_vms_and_flutter_views.dart
+++ b/packages/fuchsia_remote_debug_protocol/examples/list_vms_and_flutter_views.dart
@@ -36,13 +36,13 @@ Future<void> main(List<String> args) async {
   final FuchsiaRemoteConnection connection =
       await FuchsiaRemoteConnection.connect(address, interface, sshConfigPath);
   print('On $address, the following Dart VM ports are running:');
-  for (int port in await connection.getDeviceServicePorts()) {
+  for (final int port in await connection.getDeviceServicePorts()) {
     print('\t$port');
   }
   print('');
 
   print('The following Flutter views are running:');
-  for (FlutterView view in await connection.getFlutterViews()) {
+  for (final FlutterView view in await connection.getFlutterViews()) {
     print('\t${view.name ?? view.id}');
   }
   await connection.stop();
diff --git a/packages/fuchsia_remote_debug_protocol/lib/src/dart/dart_vm.dart b/packages/fuchsia_remote_debug_protocol/lib/src/dart/dart_vm.dart
index 547dae96f3d..847fad9e93b 100644
--- a/packages/fuchsia_remote_debug_protocol/lib/src/dart/dart_vm.dart
+++ b/packages/fuchsia_remote_debug_protocol/lib/src/dart/dart_vm.dart
@@ -170,7 +170,7 @@ class DartVm {
     final Map<String, dynamic> jsonVmRef =
         await invokeRpc('getVM', timeout: timeout);
     final List<IsolateRef> result = <IsolateRef>[];
-    for (Map<String, dynamic> jsonIsolate in jsonVmRef['isolates']) {
+    for (final Map<String, dynamic> jsonIsolate in jsonVmRef['isolates']) {
       final String name = jsonIsolate['name'] as String;
       if (pattern.matchAsPrefix(name) != null) {
         _log.fine('Found Isolate matching "$pattern": "$name"');
@@ -213,7 +213,7 @@ class DartVm {
     final List<FlutterView> views = <FlutterView>[];
     final Map<String, dynamic> rpcResponse =
         await invokeRpc('_flutter.listViews', timeout: timeout);
-    for (Map<String, dynamic> jsonView in rpcResponse['views']) {
+    for (final Map<String, dynamic> jsonView in rpcResponse['views']) {
       final FlutterView flutterView = FlutterView._fromJson(jsonView);
       if (flutterView != null) {
         views.add(flutterView);
diff --git a/packages/fuchsia_remote_debug_protocol/lib/src/fuchsia_remote_connection.dart b/packages/fuchsia_remote_debug_protocol/lib/src/fuchsia_remote_connection.dart
index 08f99064e6d..18d9f742388 100644
--- a/packages/fuchsia_remote_debug_protocol/lib/src/fuchsia_remote_connection.dart
+++ b/packages/fuchsia_remote_debug_protocol/lib/src/fuchsia_remote_connection.dart
@@ -221,7 +221,7 @@ class FuchsiaRemoteConnection {
   /// those objects) will subsequently have its connection closed as well, so
   /// behavior for them will be undefined.
   Future<void> stop() async {
-    for (PortForwarder pf in _forwardedVmServicePorts) {
+    for (final PortForwarder pf in _forwardedVmServicePorts) {
       // Closes VM service first to ensure that the connection is closed cleanly
       // on the target before shutting down the forwarding itself.
       final DartVm vmService = _dartVmCache[pf.port];
@@ -229,7 +229,7 @@ class FuchsiaRemoteConnection {
       await vmService?.stop();
       await pf.stop();
     }
-    for (PortForwarder pf in _dartVmPortMap.values) {
+    for (final PortForwarder pf in _dartVmPortMap.values) {
       final DartVm vmService = _dartVmCache[pf.port];
       _dartVmCache[pf.port] = null;
       await vmService?.stop();
@@ -305,7 +305,7 @@ class FuchsiaRemoteConnection {
     // simultaneously via Future.wait.
     final List<Future<List<IsolateRef>>> isolates =
         <Future<List<IsolateRef>>>[];
-    for (PortForwarder fp in _dartVmPortMap.values) {
+    for (final PortForwarder fp in _dartVmPortMap.values) {
       final DartVm vmService =
           await _getDartVm(fp.port, timeout: vmConnectionTimeout);
       if (vmService == null) {
@@ -390,7 +390,7 @@ class FuchsiaRemoteConnection {
       }
     }
 
-    for (PortForwarder pf in _dartVmPortMap.values) {
+    for (final PortForwarder pf in _dartVmPortMap.values) {
       final DartVm service = await _getDartVm(pf.port);
       if (service == null) {
         await shutDownPortForwarder(pf);
@@ -448,7 +448,7 @@ class FuchsiaRemoteConnection {
   Future<void> _pollVms() async {
     await _checkPorts();
     final List<int> servicePorts = await getDeviceServicePorts();
-    for (int servicePort in servicePorts) {
+    for (final int servicePort in servicePorts) {
       if (!_stalePorts.contains(servicePort) &&
           !_dartVmPortMap.containsKey(servicePort)) {
         _dartVmPortMap[servicePort] = await fuchsiaPortForwardingFunction(
@@ -499,7 +499,7 @@ class FuchsiaRemoteConnection {
               _sshCommandRunner.sshConfigPath);
         }));
 
-    for (PortForwarder pf in forwardedVmServicePorts) {
+    for (final PortForwarder pf in forwardedVmServicePorts) {
       // TODO(awdavies): Handle duplicates.
       _dartVmPortMap[pf.remotePort] = pf;
     }
@@ -521,13 +521,13 @@ class FuchsiaRemoteConnection {
     final List<String> portPaths = await _sshCommandRunner
         .run('/bin/find /hub -name vmservice-port');
     final List<int> ports = <int>[];
-    for (String path in portPaths) {
+    for (final String path in portPaths) {
       if (path == '') {
         continue;
       }
       final List<String> lsOutput =
           await _sshCommandRunner.run('/bin/ls $path');
-      for (String line in lsOutput) {
+      for (final String line in lsOutput) {
         if (line == '') {
           continue;
         }