Native assets: package in framework on iOS and MacOS (#140907)

Packages the native assets for iOS and MacOS in frameworks.

Issue:

* https://github.com/flutter/flutter/issues/140544
* https://github.com/flutter/flutter/issues/129757

## Details

* [x] This packages dylibs from the native assets feature in frameworks. It packages every dylib in a separate framework.
* [x] The dylib name is updated to use `@rpath` instead of `@executable_path`.
* [x] The dylibs for flutter-tester are no longer modified to change the install name. (Previously it was wrongly updating the install name to the location the dylib would have once deployed in an app.)
* [x] Use symlinking on MacOS.

dev/devicelab/bin/tasks/module_test_ios.dart

@@ -250,9 +250,7 @@ dependencies:
       checkDirectoryNotExists(path.join(ephemeralIOSHostApp.path, 'Frameworks', '$dartPluginName.framework'));
 
       // Native assets embedded, no embedded framework.
-      const String libFfiPackageDylib = 'lib$ffiPackageName.dylib';
+      checkFileExists(path.join(ephemeralIOSHostApp.path, 'Frameworks', '$ffiPackageName.framework', ffiPackageName));
-      checkFileExists(path.join(ephemeralIOSHostApp.path, 'Frameworks', libFfiPackageDylib));
-      checkDirectoryNotExists(path.join(ephemeralIOSHostApp.path, 'Frameworks', '$ffiPackageName.framework'));
 
       section('Clean and pub get module');
 
@@ -385,7 +383,8 @@ end
 
       checkFileExists(path.join(
         hostFrameworksDirectory,
-        libFfiPackageDylib,
+        '$ffiPackageName.framework',
+        ffiPackageName,
       ));
 
       section('Check the NOTICE file is correct');
@@ -491,7 +490,8 @@ end
         checkFileExists(path.join(
           archivedAppPath,
           'Frameworks',
-          libFfiPackageDylib,
+          '$ffiPackageName.framework',
+          ffiPackageName,
         ));
 
         // The host app example builds plugins statically, url_launcher_ios.framework

packages/flutter_tools/lib/src/ios/native_assets.dart

@@ -106,7 +106,7 @@ Future<List<Uri>> buildNativeAssetsIOS({
   ensureNoLinkModeStatic(nativeAssets);
   globals.logger.printTrace('Building native assets for $targets done.');
   final Map<AssetPath, List<Asset>> fatAssetTargetLocations = _fatAssetTargetLocations(nativeAssets);
-  await copyNativeAssetsMacOSHost(
+  await _copyNativeAssetsIOS(
     buildUri,
     fatAssetTargetLocations,
     codesignIdentity,
@@ -145,21 +145,25 @@ Target _getNativeTarget(DarwinArch darwinArch) {
 }
 
 Map<AssetPath, List<Asset>> _fatAssetTargetLocations(List<Asset> nativeAssets) {
+  final Set<String> alreadyTakenNames = <String>{};
   final Map<AssetPath, List<Asset>> result = <AssetPath, List<Asset>>{};
   for (final Asset asset in nativeAssets) {
-    final AssetPath path = _targetLocationIOS(asset).path;
+    final AssetPath path = _targetLocationIOS(asset, alreadyTakenNames).path;
     result[path] ??= <Asset>[];
     result[path]!.add(asset);
   }
   return result;
 }
 
-Map<Asset, Asset> _assetTargetLocations(List<Asset> nativeAssets) => <Asset, Asset>{
+Map<Asset, Asset> _assetTargetLocations(List<Asset> nativeAssets) {
+  final Set<String> alreadyTakenNames = <String>{};
+  return <Asset, Asset>{
     for (final Asset asset in nativeAssets)
-    asset: _targetLocationIOS(asset),
+      asset: _targetLocationIOS(asset, alreadyTakenNames),
   };
+}
 
-Asset _targetLocationIOS(Asset asset) {
+Asset _targetLocationIOS(Asset asset, Set<String> alreadyTakenNames) {
   final AssetPath path = asset.path;
   switch (path) {
     case AssetSystemPath _:
@@ -168,7 +172,52 @@ Asset _targetLocationIOS(Asset asset) {
       return asset;
     case AssetAbsolutePath _:
       final String fileName = path.uri.pathSegments.last;
-      return asset.copyWith(path: AssetAbsolutePath(Uri(path: fileName)));
+      return asset.copyWith(
+        path: AssetAbsolutePath(frameworkUri(fileName, alreadyTakenNames)),
+      );
+  }
+  throw Exception(
+      'Unsupported asset path type ${path.runtimeType} in asset $asset');
+}
+
+/// Copies native assets into a framework per dynamic library.
+///
+/// For `flutter run -release` a multi-architecture solution is needed. So,
+/// `lipo` is used to combine all target architectures into a single file.
+///
+/// The install name is set so that it matches what the place it will
+/// be bundled in the final app.
+///
+/// Code signing is also done here, so that it doesn't have to be done in
+/// in xcode_backend.dart.
+Future<void> _copyNativeAssetsIOS(
+  Uri buildUri,
+  Map<AssetPath, List<Asset>> assetTargetLocations,
+  String? codesignIdentity,
+  BuildMode buildMode,
+  FileSystem fileSystem,
+) async {
+  if (assetTargetLocations.isNotEmpty) {
+    globals.logger
+        .printTrace('Copying native assets to ${buildUri.toFilePath()}.');
+    for (final MapEntry<AssetPath, List<Asset>> assetMapping
+        in assetTargetLocations.entries) {
+      final Uri target = (assetMapping.key as AssetAbsolutePath).uri;
+      final List<Uri> sources = <Uri>[
+        for (final Asset source in assetMapping.value)
+          (source.path as AssetAbsolutePath).uri
+      ];
+      final Uri targetUri = buildUri.resolveUri(target);
+      final File dylibFile = fileSystem.file(targetUri);
+      final Directory frameworkDir = dylibFile.parent;
+      if (!await frameworkDir.exists()) {
+        await frameworkDir.create(recursive: true);
+      }
+      await lipoDylibs(dylibFile, sources);
+      await setInstallNameDylib(dylibFile);
+      await createInfoPlist(targetUri.pathSegments.last, frameworkDir);
+      await codesignDylib(codesignIdentity, buildMode, frameworkDir);
+    }
+    globals.logger.printTrace('Copying native assets done.');
   }
-  throw Exception('Unsupported asset path type ${path.runtimeType} in asset $asset');
 }

packages/flutter_tools/lib/src/macos/native_assets.dart

@@ -108,7 +108,23 @@ Future<(Uri? nativeAssetsYaml, List<Uri> dependencies)> buildNativeAssetsMacOS({
   final Uri? absolutePath = flutterTester ? buildUri : null;
   final Map<Asset, Asset> assetTargetLocations = _assetTargetLocations(nativeAssets, absolutePath);
   final Map<AssetPath, List<Asset>> fatAssetTargetLocations = _fatAssetTargetLocations(nativeAssets, absolutePath);
-  await copyNativeAssetsMacOSHost(buildUri, fatAssetTargetLocations, codesignIdentity, buildMode, fileSystem);
+  if (flutterTester) {
+    await _copyNativeAssetsMacOSFlutterTester(
+      buildUri,
+      fatAssetTargetLocations,
+      codesignIdentity,
+      buildMode,
+      fileSystem,
+    );
+  } else {
+    await _copyNativeAssetsMacOS(
+      buildUri,
+      fatAssetTargetLocations,
+      codesignIdentity,
+      buildMode,
+      fileSystem,
+    );
+  }
   final Uri nativeAssetsUri = await writeNativeAssetsYaml(assetTargetLocations.values, yamlParentDirectory ?? buildUri, fileSystem);
   return (nativeAssetsUri, dependencies.toList());
 }
@@ -125,22 +141,40 @@ Target _getNativeTarget(DarwinArch darwinArch) {
   }
 }
 
-Map<AssetPath, List<Asset>> _fatAssetTargetLocations(List<Asset> nativeAssets, Uri? absolutePath) {
+Map<AssetPath, List<Asset>> _fatAssetTargetLocations(
+  List<Asset> nativeAssets,
+  Uri? absolutePath,
+) {
+  final Set<String> alreadyTakenNames = <String>{};
   final Map<AssetPath, List<Asset>> result = <AssetPath, List<Asset>>{};
   for (final Asset asset in nativeAssets) {
-    final AssetPath path = _targetLocationMacOS(asset, absolutePath).path;
+    final AssetPath path = _targetLocationMacOS(
+      asset,
+      absolutePath,
+      alreadyTakenNames,
+    ).path;
     result[path] ??= <Asset>[];
     result[path]!.add(asset);
   }
   return result;
 }
 
-Map<Asset, Asset> _assetTargetLocations(List<Asset> nativeAssets, Uri? absolutePath) => <Asset, Asset>{
+Map<Asset, Asset> _assetTargetLocations(
+  List<Asset> nativeAssets,
+  Uri? absolutePath,
+) {
+  final Set<String> alreadyTakenNames = <String>{};
+  return <Asset, Asset>{
     for (final Asset asset in nativeAssets)
-    asset: _targetLocationMacOS(asset, absolutePath),
+      asset: _targetLocationMacOS(asset, absolutePath, alreadyTakenNames),
   };
+}
 
-Asset _targetLocationMacOS(Asset asset, Uri? absolutePath) {
+Asset _targetLocationMacOS(
+  Asset asset,
+  Uri? absolutePath,
+  Set<String> alreadyTakenNames,
+) {
   final AssetPath path = asset.path;
   switch (path) {
     case AssetSystemPath _:
@@ -157,9 +191,119 @@ Asset _targetLocationMacOS(Asset asset, Uri? absolutePath) {
         // Flutter Desktop needs "absolute" paths inside the app.
         // "relative" in the context of native assets would be relative to the
         // kernel or aot snapshot.
-        uri = Uri(path: fileName);
+        uri = frameworkUri(fileName, alreadyTakenNames);
+
       }
       return asset.copyWith(path: AssetAbsolutePath(uri));
   }
   throw Exception('Unsupported asset path type ${path.runtimeType} in asset $asset');
 }
+
+/// Copies native assets into a framework per dynamic library.
+///
+/// The framework contains symlinks according to
+/// https://developer.apple.com/library/archive/documentation/MacOSX/Conceptual/BPFrameworks/Concepts/FrameworkAnatomy.html
+///
+/// For `flutter run -release` a multi-architecture solution is needed. So,
+/// `lipo` is used to combine all target architectures into a single file.
+///
+/// The install name is set so that it matches what the place it will
+/// be bundled in the final app.
+///
+/// Code signing is also done here, so that it doesn't have to be done in
+/// in macos_assemble.sh.
+Future<void> _copyNativeAssetsMacOS(
+  Uri buildUri,
+  Map<AssetPath, List<Asset>> assetTargetLocations,
+  String? codesignIdentity,
+  BuildMode buildMode,
+  FileSystem fileSystem,
+) async {
+  if (assetTargetLocations.isNotEmpty) {
+    globals.logger.printTrace('Copying native assets to ${buildUri.toFilePath()}.');
+    for (final MapEntry<AssetPath, List<Asset>> assetMapping in assetTargetLocations.entries) {
+      final Uri target = (assetMapping.key as AssetAbsolutePath).uri;
+      final List<Uri> sources = <Uri>[
+        for (final Asset source in assetMapping.value)
+          (source.path as AssetAbsolutePath).uri,
+      ];
+      final Uri targetUri = buildUri.resolveUri(target);
+      final String name = targetUri.pathSegments.last;
+      final Directory frameworkDir = fileSystem.file(targetUri).parent;
+      if (await frameworkDir.exists()) {
+        await frameworkDir.delete(recursive: true);
+      }
+      // MyFramework.framework/                           frameworkDir
+      //   MyFramework  -> Versions/Current/MyFramework   dylibLink
+      //   Resources    -> Versions/Current/Resources     resourcesLink
+      //   Versions/                                      versionsDir
+      //     A/                                           versionADir
+      //       MyFramework                                dylibFile
+      //       Resources/                                 resourcesDir
+      //         Info.plist
+      //     Current  -> A                                currentLink
+      final Directory versionsDir = frameworkDir.childDirectory('Versions');
+      final Directory versionADir = versionsDir.childDirectory('A');
+      final Directory resourcesDir = versionADir.childDirectory('Resources');
+      await resourcesDir.create(recursive: true);
+      final File dylibFile = versionADir.childFile(name);
+      final Link currentLink = versionsDir.childLink('Current');
+      await currentLink.create(fileSystem.path.relative(
+        versionADir.path,
+        from: currentLink.parent.path,
+      ));
+      final Link resourcesLink = frameworkDir.childLink('Resources');
+      await resourcesLink.create(fileSystem.path.relative(
+        resourcesDir.path,
+        from: resourcesLink.parent.path,
+      ));
+      await lipoDylibs(dylibFile, sources);
+      final Link dylibLink = frameworkDir.childLink(name);
+      await dylibLink.create(fileSystem.path.relative(
+        versionsDir.childDirectory('Current').childFile(name).path,
+        from: dylibLink.parent.path,
+      ));
+      await setInstallNameDylib(dylibFile);
+      await createInfoPlist(name, resourcesDir);
+      await codesignDylib(codesignIdentity, buildMode, frameworkDir);
+    }
+    globals.logger.printTrace('Copying native assets done.');
+  }
+}
+
+
+/// Copies native assets for flutter tester.
+///
+/// For `flutter run -release` a multi-architecture solution is needed. So,
+/// `lipo` is used to combine all target architectures into a single file.
+///
+/// In contrast to [_copyNativeAssetsMacOS], it does not set the install name.
+///
+/// Code signing is also done here.
+Future<void> _copyNativeAssetsMacOSFlutterTester(
+  Uri buildUri,
+  Map<AssetPath, List<Asset>> assetTargetLocations,
+  String? codesignIdentity,
+  BuildMode buildMode,
+  FileSystem fileSystem,
+) async {
+  if (assetTargetLocations.isNotEmpty) {
+    globals.logger.printTrace('Copying native assets to ${buildUri.toFilePath()}.');
+    for (final MapEntry<AssetPath, List<Asset>> assetMapping in assetTargetLocations.entries) {
+      final Uri target = (assetMapping.key as AssetAbsolutePath).uri;
+      final List<Uri> sources = <Uri>[
+        for (final Asset source in assetMapping.value)
+          (source.path as AssetAbsolutePath).uri,
+      ];
+      final Uri targetUri = buildUri.resolveUri(target);
+      final File dylibFile = fileSystem.file(targetUri);
+      final Directory targetParent = dylibFile.parent;
+      if (!await targetParent.exists()) {
+        await targetParent.create(recursive: true);
+      }
+      await lipoDylibs(dylibFile, sources);
+      await codesignDylib(codesignIdentity, buildMode, dylibFile);
+    }
+    globals.logger.printTrace('Copying native assets done.');
+  }
+}

packages/flutter_tools/lib/src/macos/native_assets_host.dart

@@ -13,41 +13,40 @@ import '../build_info.dart';
 import '../convert.dart';
 import '../globals.dart' as globals;
 
-/// The target location for native assets on macOS.
+/// Create an `Info.plist` in [target] for a framework with a single dylib.
 ///
-/// Because we need to have a multi-architecture solution for
+/// The framework must be named [name].framework and the dylib [name].
-/// `flutter run --release`, we use `lipo` to combine all target architectures
+Future<void> createInfoPlist(
-/// into a single file.
+  String name,
-///
+  Directory target,
-/// We need to set the install name so that it matches what the place it will
-/// be bundled in the final app.
-///
-/// Code signing is also done here, so that we don't have to worry about it
-/// in xcode_backend.dart and macos_assemble.sh.
-Future<void> copyNativeAssetsMacOSHost(
-  Uri buildUri,
-  Map<AssetPath, List<Asset>> assetTargetLocations,
-  String? codesignIdentity,
-  BuildMode buildMode,
-  FileSystem fileSystem,
 ) async {
-  if (assetTargetLocations.isNotEmpty) {
+  final File infoPlistFile = target.childFile('Info.plist');
-    globals.logger.printTrace('Copying native assets to ${buildUri.toFilePath()}.');
+  await infoPlistFile.writeAsString('''
-    final Directory buildDir = fileSystem.directory(buildUri.toFilePath());
+<?xml version="1.0" encoding="UTF-8"?>
-    if (!buildDir.existsSync()) {
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
-      buildDir.createSync(recursive: true);
+<plist version="1.0">
-    }
+<dict>
-    for (final MapEntry<AssetPath, List<Asset>> assetMapping in assetTargetLocations.entries) {
+	<key>CFBundleDevelopmentRegion</key>
-      final Uri target = (assetMapping.key as AssetAbsolutePath).uri;
+	 <string>en</string>
-      final List<Uri> sources = <Uri>[for (final Asset source in assetMapping.value) (source.path as AssetAbsolutePath).uri];
+	<key>CFBundleExecutable</key>
-      final Uri targetUri = buildUri.resolveUri(target);
+	<string>$name</string>
-      final String targetFullPath = targetUri.toFilePath();
+	<key>CFBundleIdentifier</key>
-      await lipoDylibs(targetFullPath, sources);
+	<string>io.flutter.flutter.native_assets.$name</string>
-      await setInstallNameDylib(targetUri);
+	<key>CFBundleInfoDictionaryVersion</key>
-      await codesignDylib(codesignIdentity, buildMode, targetFullPath);
+	<string>6.0</string>
-    }
+	<key>CFBundleName</key>
-    globals.logger.printTrace('Copying native assets done.');
+	<string>$name</string>
-  }
+	<key>CFBundlePackageType</key>
+	<string>FMWK</string>
+	<key>CFBundleShortVersionString</key>
+	<string>1.0</string>
+	<key>CFBundleSignature</key>
+	<string>????</string>
+	<key>CFBundleVersion</key>
+	<string>1.0</string>
+</dict>
+</plist>
+  ''');
 }
 
 /// Combines dylibs from [sources] into a fat binary at [targetFullPath].
@@ -55,13 +54,13 @@ Future<void> copyNativeAssetsMacOSHost(
 /// The dylibs must have different architectures. E.g. a dylib targeting
 /// arm64 ios simulator cannot be combined with a dylib targeting arm64
 /// ios device or macos arm64.
-Future<void> lipoDylibs(String targetFullPath, List<Uri> sources) async {
+Future<void> lipoDylibs(File target, List<Uri> sources) async {
   final ProcessResult lipoResult = await globals.processManager.run(
     <String>[
       'lipo',
       '-create',
       '-output',
-      targetFullPath,
+      target.path,
       for (final Uri source in sources) source.toFilePath(),
     ],
   );
@@ -78,25 +77,27 @@ Future<void> lipoDylibs(String targetFullPath, List<Uri> sources) async {
 /// dylib itself does not correspond to the path that the file is at. Therefore,
 /// native assets copied into their final location also need their install name
 /// updated with the `install_name_tool`.
-Future<void> setInstallNameDylib(Uri targetUri) async {
+Future<void> setInstallNameDylib(File dylibFile) async {
-  final String fileName = targetUri.pathSegments.last;
+  final String fileName = dylibFile.basename;
   final ProcessResult installNameResult = await globals.processManager.run(
     <String>[
       'install_name_tool',
       '-id',
-      '@executable_path/Frameworks/$fileName',
+      '@rpath/$fileName.framework/$fileName',
-      targetUri.toFilePath(),
+      dylibFile.path,
     ],
   );
   if (installNameResult.exitCode != 0) {
-    throwToolExit('Failed to change the install name of $targetUri:\n${installNameResult.stderr}');
+    throwToolExit(
+      'Failed to change the install name of $dylibFile:\n${installNameResult.stderr}',
+    );
   }
 }
 
 Future<void> codesignDylib(
   String? codesignIdentity,
   BuildMode buildMode,
-  String targetFullPath,
+  FileSystemEntity target,
 ) async {
   if (codesignIdentity == null || codesignIdentity.isEmpty) {
     codesignIdentity = '-';
@@ -110,12 +111,17 @@ Future<void> codesignDylib(
       // Mimic Xcode's timestamp codesigning behavior on non-release binaries.
       '--timestamp=none',
     ],
-    targetFullPath,
+    target.path,
   ];
   globals.logger.printTrace(codesignCommand.join(' '));
-  final ProcessResult codesignResult = await globals.processManager.run(codesignCommand);
+  final ProcessResult codesignResult = await globals.processManager.run(
+    codesignCommand,
+  );
   if (codesignResult.exitCode != 0) {
-    throwToolExit('Failed to code sign binary:\n${codesignResult.stderr}');
+    throwToolExit(
+      'Failed to code sign binary: exit code: ${codesignResult.exitCode} '
+      '${codesignResult.stdout} ${codesignResult.stderr}',
+    );
   }
   globals.logger.printTrace(codesignResult.stdout as String);
   globals.logger.printTrace(codesignResult.stderr as String);
@@ -125,7 +131,9 @@ Future<void> codesignDylib(
 ///
 /// Use the `clang`, `ar`, and `ld` that would be used if run with `xcrun`.
 Future<CCompilerConfig> cCompilerConfigMacOS() async {
-  final ProcessResult xcrunResult = await globals.processManager.run(<String>['xcrun', 'clang', '--version']);
+  final ProcessResult xcrunResult = await globals.processManager.run(
+    <String>['xcrun', 'clang', '--version'],
+  );
   if (xcrunResult.exitCode != 0) {
     throwToolExit('Failed to find clang with xcrun:\n${xcrunResult.stderr}');
   }
@@ -139,3 +147,61 @@ Future<CCompilerConfig> cCompilerConfigMacOS() async {
     ld: Uri.file('$installPath/ld'),
   );
 }
+
+/// Converts [fileName] into a suitable framework name.
+///
+/// On MacOS and iOS, dylibs need to be packaged in a framework.
+///
+/// In order for resolution to work, the file name inside the framework must be
+/// equal to the framework name.
+///
+/// Dylib names on MacOS/iOS usually have a dylib extension. If so, remove it.
+///
+/// Dylib names on MacOS/iOS are usually prefixed with 'lib'. So, if the file is
+/// a dylib, try to remove the prefix.
+///
+/// The bundle ID string must contain only alphanumeric characters
+/// (A–Z, a–z, and 0–9), hyphens (-), and periods (.).
+/// https://developer.apple.com/documentation/bundleresources/information_property_list/cfbundleidentifier
+///
+/// This name can contain up to 15 characters.
+/// https://developer.apple.com/documentation/bundleresources/information_property_list/cfbundlename
+///
+/// The [alreadyTakenNames] are used to ensure that the framework name does not
+/// conflict with previously chosen names.
+Uri frameworkUri(String fileName, Set<String> alreadyTakenNames) {
+  final List<String> splitFileName = fileName.split('.');
+  final bool isDylib;
+  if (splitFileName.length >= 2) {
+    isDylib = splitFileName.last == 'dylib';
+    if (isDylib) {
+      fileName = splitFileName.sublist(0, splitFileName.length - 1).join('.');
+    }
+  } else {
+    isDylib = false;
+  }
+  if (isDylib && fileName.startsWith('lib')) {
+    fileName = fileName.replaceFirst('lib', '');
+  }
+  fileName = fileName.replaceAll(RegExp(r'[^A-Za-z0-9_-]'), '');
+  if (fileName.length > 15) {
+    fileName = fileName.substring(0, 15);
+  }
+  if (alreadyTakenNames.contains(fileName)) {
+    if (fileName.length > 12) {
+      fileName = fileName.substring(0, 12);
+    }
+    final String prefixName = fileName;
+    for (int i = 1; i < 1000; i++) {
+      fileName = '$prefixName$i';
+      if (!alreadyTakenNames.contains(fileName)) {
+        break;
+      }
+    }
+    if (alreadyTakenNames.contains(fileName)) {
+      throwToolExit('Failed to rename $fileName in native assets packaging.');
+    }
+  }
+  alreadyTakenNames.add(fileName);
+  return Uri(path: '$fileName.framework/$fileName');
+}

packages/flutter_tools/test/general.shard/build_system/targets/native_assets_test.dart

@@ -135,7 +135,7 @@ void main() {
             linkMode: native_assets_cli.LinkMode.dynamic,
             target: native_assets_cli.Target.iOSArm64,
             path: native_assets_cli.AssetAbsolutePath(
-              Uri.file('libfoo.dylib'),
+              Uri.file('foo.framework/foo'),
             ),
           )
         ], dependencies: <Uri>[
@@ -165,7 +165,7 @@ void main() {
         nativeAssetsYaml.readAsStringSync(),
         stringContainsInOrder(<String>[
           'package:foo/foo.dart',
-          'libfoo.dylib',
+          'foo.framework',
         ]),
       );
     },

packages/flutter_tools/test/general.shard/ios/native_assets_test.dart

@@ -130,13 +130,13 @@ void main() {
               id: 'package:bar/bar.dart',
               linkMode: LinkMode.dynamic,
               target: native_assets_cli.Target.macOSArm64,
-              path: AssetAbsolutePath(Uri.file('bar.dylib')),
+              path: AssetAbsolutePath(Uri.file('libbar.dylib')),
             ),
             Asset(
               id: 'package:bar/bar.dart',
               linkMode: LinkMode.dynamic,
               target: native_assets_cli.Target.macOSX64,
-              path: AssetAbsolutePath(Uri.file('bar.dylib')),
+              path: AssetAbsolutePath(Uri.file('libbar.dylib')),
             ),
           ],
         ),
@@ -219,16 +219,16 @@ void main() {
             'lipo',
             '-create',
             '-output',
-            '/build/native_assets/ios/bar.dylib',
+            '/build/native_assets/ios/bar.framework/bar',
-            'bar.dylib',
+            'libbar.dylib',
           ],
         ),
         const FakeCommand(
           command: <Pattern>[
             'install_name_tool',
             '-id',
-            '@executable_path/Frameworks/bar.dylib',
+            '@rpath/bar.framework/bar',
-            '/build/native_assets/ios/bar.dylib',
+            '/build/native_assets/ios/bar.framework/bar'
           ],
         ),
         const FakeCommand(
@@ -238,7 +238,7 @@ void main() {
             '--sign',
             '-',
             '--timestamp=none',
-            '/build/native_assets/ios/bar.dylib',
+            '/build/native_assets/ios/bar.framework',
           ],
         ),
       ],
@@ -267,7 +267,7 @@ void main() {
               id: 'package:bar/bar.dart',
               linkMode: LinkMode.dynamic,
               target: native_assets_cli.Target.iOSArm64,
-              path: AssetAbsolutePath(Uri.file('bar.dylib')),
+              path: AssetAbsolutePath(Uri.file('libbar.dylib')),
             ),
           ],
         ),

packages/flutter_tools/test/general.shard/macos/native_assets_host_test.dart

@@ -0,0 +1,68 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_tools/src/macos/native_assets_host.dart';
+
+import '../../src/common.dart';
+
+void main() {
+  test('framework name', () {
+    expect(
+      frameworkUri('libfoo.dylib', <String>{}),
+      equals(Uri.file('foo.framework/foo')),
+    );
+    expect(
+      frameworkUri('foo', <String>{}),
+      equals(Uri.file('foo.framework/foo')),
+    );
+    expect(
+      frameworkUri('foo_foo', <String>{}),
+      equals(Uri.file('foo_foo.framework/foo_foo')),
+    );
+    expect(
+      frameworkUri('foo-foo', <String>{}),
+      equals(Uri.file('foo-foo.framework/foo-foo')),
+    );
+    expect(
+      frameworkUri(r'foo$foo', <String>{}),
+      equals(Uri.file('foofoo.framework/foofoo')),
+    );
+    expect(
+      frameworkUri('foo.foo', <String>{}),
+      equals(Uri.file('foofoo.framework/foofoo')),
+    );
+    expect(
+      frameworkUri('libatoolongfilenameforaframework.dylib', <String>{}),
+      equals(Uri.file('atoolongfilenam.framework/atoolongfilenam')),
+    );
+  });
+
+  test('framework name name confilicts', () {
+    final Set<String> alreadyTakenNames = <String>{};
+    expect(
+      frameworkUri('libfoo.dylib', alreadyTakenNames),
+      equals(Uri.file('foo.framework/foo')),
+    );
+    expect(
+      frameworkUri('libfoo.dylib', alreadyTakenNames),
+      equals(Uri.file('foo1.framework/foo1')),
+    );
+    expect(
+      frameworkUri('libfoo.dylib', alreadyTakenNames),
+      equals(Uri.file('foo2.framework/foo2')),
+    );
+    expect(
+      frameworkUri('libatoolongfilenameforaframework.dylib', alreadyTakenNames),
+      equals(Uri.file('atoolongfilenam.framework/atoolongfilenam')),
+    );
+    expect(
+      frameworkUri('libatoolongfilenameforaframework.dylib', alreadyTakenNames),
+      equals(Uri.file('atoolongfile1.framework/atoolongfile1')),
+    );
+    expect(
+      frameworkUri('libatoolongfilenameforaframework.dylib', alreadyTakenNames),
+      equals(Uri.file('atoolongfile2.framework/atoolongfile2')),
+    );
+  });
+}

packages/flutter_tools/test/general.shard/macos/native_assets_test.dart

@@ -149,13 +149,13 @@ void main() {
               id: 'package:bar/bar.dart',
               linkMode: LinkMode.dynamic,
               target: native_assets_cli.Target.macOSArm64,
-              path: AssetAbsolutePath(Uri.file('bar.dylib')),
+              path: AssetAbsolutePath(Uri.file('libbar.dylib')),
             ),
             Asset(
               id: 'package:bar/bar.dart',
               linkMode: LinkMode.dynamic,
               target: native_assets_cli.Target.macOSX64,
-              path: AssetAbsolutePath(Uri.file('bar.dylib')),
+              path: AssetAbsolutePath(Uri.file('libbar.dylib')),
             ),
           ],
         ),
@@ -236,35 +236,47 @@ void main() {
     if (flutterTester) {
       testName += ' flutter tester';
     }
+    final String dylibPath;
+    final String signPath;
+    if (flutterTester) {
+      // Just the dylib.
+      dylibPath = '/build/native_assets/macos/libbar.dylib';
+      signPath = '/build/native_assets/macos/libbar.dylib';
+    } else {
+      // Packaged in framework.
+      dylibPath = '/build/native_assets/macos/bar.framework/Versions/A/bar';
+      signPath = '/build/native_assets/macos/bar.framework';
+    }
     testUsingContext('build with assets$testName', overrides: <Type, Generator>{
       FeatureFlags: () => TestFeatureFlags(isNativeAssetsEnabled: true),
       ProcessManager: () => FakeProcessManager.list(
         <FakeCommand>[
-          const FakeCommand(
+          FakeCommand(
             command: <Pattern>[
               'lipo',
               '-create',
               '-output',
-              '/build/native_assets/macos/bar.dylib',
+              dylibPath,
-              'bar.dylib',
+              'libbar.dylib',
             ],
           ),
-          const FakeCommand(
+          if  (!flutterTester)
+            FakeCommand(
               command: <Pattern>[
                 'install_name_tool',
                 '-id',
-              '@executable_path/Frameworks/bar.dylib',
+                '@rpath/bar.framework/bar',
-              '/build/native_assets/macos/bar.dylib',
+                dylibPath,
               ],
             ),
-          const FakeCommand(
+          FakeCommand(
             command: <Pattern>[
               'codesign',
               '--force',
               '--sign',
               '-',
               '--timestamp=none',
-              '/build/native_assets/macos/bar.dylib',
+              signPath,
             ],
           ),
         ],
@@ -292,7 +304,7 @@ void main() {
                 id: 'package:bar/bar.dart',
                 linkMode: LinkMode.dynamic,
                 target: native_assets_cli.Target.macOSArm64,
-                path: AssetAbsolutePath(Uri.file('bar.dylib')),
+                path: AssetAbsolutePath(Uri.file('libbar.dylib')),
               ),
             ],
           ),
@@ -315,10 +327,10 @@ void main() {
           'package:bar/bar.dart',
           if (flutterTester)
             // Tests run on host system, so the have the full path on the system.
-            '- ${projectUri.resolve('build/native_assets/macos/bar.dylib').toFilePath()}'
+            '- ${projectUri.resolve('build/native_assets/macos/libbar.dylib').toFilePath()}'
           else
             // Apps are a bundle with the dylibs on their dlopen path.
-            '- bar.dylib',
+            '- bar.framework/bar',
         ]),
       );
     });

packages/flutter_tools/test/integration.shard/native_assets_test.dart

@@ -292,18 +292,48 @@ void main() {
 void expectDylibIsBundledMacOS(Directory appDirectory, String buildMode) {
   final Directory appBundle = appDirectory.childDirectory('build/$hostOs/Build/Products/${buildMode.upperCaseFirst()}/$exampleAppName.app');
   expect(appBundle, exists);
-  final Directory dylibsFolder = appBundle.childDirectory('Contents/Frameworks');
+  final Directory frameworksFolder =
-  expect(dylibsFolder, exists);
+      appBundle.childDirectory('Contents/Frameworks');
-  final File dylib = dylibsFolder.childFile(OS.macOS.dylibFileName(packageName));
+  expect(frameworksFolder, exists);
-  expect(dylib, exists);
+
+  // MyFramework.framework/
+  //   MyFramework  -> Versions/Current/MyFramework
+  //   Resources    -> Versions/Current/Resources
+  //   Versions/
+  //     A/
+  //       MyFramework
+  //       Resources/
+  //         Info.plist
+  //     Current  -> A
+  final String frameworkName = packageName.substring(0, 15);
+  final Directory frameworkDir =
+      frameworksFolder.childDirectory('$frameworkName.framework');
+  final Directory versionsDir = frameworkDir.childDirectory('Versions');
+  final Directory versionADir = versionsDir.childDirectory('A');
+  final Directory resourcesDir = versionADir.childDirectory('Resources');
+  expect(resourcesDir, exists);
+  final File dylibFile = versionADir.childFile(frameworkName);
+  expect(dylibFile, exists);
+  final Link currentLink = versionsDir.childLink('Current');
+  expect(currentLink, exists);
+  expect(currentLink.resolveSymbolicLinksSync(), versionADir.path);
+  final Link resourcesLink = frameworkDir.childLink('Resources');
+  expect(resourcesLink, exists);
+  expect(resourcesLink.resolveSymbolicLinksSync(), resourcesDir.path);
+  final Link dylibLink = frameworkDir.childLink(frameworkName);
+  expect(dylibLink, exists);
+  expect(dylibLink.resolveSymbolicLinksSync(), dylibFile.path);
 }
 
 void expectDylibIsBundledIos(Directory appDirectory, String buildMode) {
   final Directory appBundle = appDirectory.childDirectory('build/ios/${buildMode.upperCaseFirst()}-iphoneos/Runner.app');
   expect(appBundle, exists);
-  final Directory dylibsFolder = appBundle.childDirectory('Frameworks');
+  final Directory frameworksFolder = appBundle.childDirectory('Frameworks');
-  expect(dylibsFolder, exists);
+  expect(frameworksFolder, exists);
-  final File dylib = dylibsFolder.childFile(OS.iOS.dylibFileName(packageName));
+  final String frameworkName = packageName.substring(0, 15);
+  final File dylib = frameworksFolder
+      .childDirectory('$frameworkName.framework')
+      .childFile(frameworkName);
   expect(dylib, exists);
 }
 
@@ -379,7 +409,10 @@ void expectDylibIsBundledAndroid(Directory appDirectory, String buildMode) {
 void expectDylibIsBundledWithFrameworks(Directory appDirectory, String buildMode, String os) {
   final Directory frameworksFolder = appDirectory.childDirectory('build/$os/framework/${buildMode.upperCaseFirst()}');
   expect(frameworksFolder, exists);
-  final File dylib = frameworksFolder.childFile(OS.macOS.dylibFileName(packageName));
+  final String frameworkName = packageName.substring(0, 15);
+  final File dylib = frameworksFolder
+      .childDirectory('$frameworkName.framework')
+      .childFile(frameworkName);
   expect(dylib, exists);
 }