add directionality to CupertinoDialog (#167403)

Fixes `CupertinoDialog` not respecting Directionality for actions
Issue refers to AlertDIalog.adaptive, but I have found that problem
occurs only in `CupertinoDialog`.

## Related Issues
* Fixes [Dialog actions do not respect Directionality
#166880](https://github.com/flutter/flutter/issues/166880)

## Tests
Added 1 test

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

packages/flutter/lib/src/cupertino/dialog.dart

@@ -2307,23 +2307,31 @@ class _AlertDialogActionsLayout extends MultiChildRenderObjectWidget {
 
   @override
   RenderObject createRenderObject(BuildContext context) {
-    return _RenderAlertDialogActionsLayout(dividerThickness: _dividerThickness);
+    return _RenderAlertDialogActionsLayout(
+      dividerThickness: _dividerThickness,
+      textDirection: Directionality.of(context),
+    );
   }
 
   @override
   void updateRenderObject(BuildContext context, _RenderAlertDialogActionsLayout renderObject) {
-    renderObject.dividerThickness = _dividerThickness;
+    renderObject
+      ..dividerThickness = _dividerThickness
+      ..textDirection = Directionality.of(context);
   }
 }
 
 class _RenderAlertDialogActionsLayout extends RenderFlex {
-  _RenderAlertDialogActionsLayout({List<RenderBox>? children, required double dividerThickness})
-    : _dividerThickness = dividerThickness,
-      super(
-        direction: Axis.vertical,
-        mainAxisSize: MainAxisSize.min,
-        crossAxisAlignment: CrossAxisAlignment.stretch,
-      ) {
+  _RenderAlertDialogActionsLayout({
+    List<RenderBox>? children,
+    required double dividerThickness,
+    super.textDirection,
+  }) : _dividerThickness = dividerThickness,
+       super(
+         direction: Axis.vertical,
+         mainAxisSize: MainAxisSize.min,
+         crossAxisAlignment: CrossAxisAlignment.stretch,
+       ) {
     addAll(children);
   }
 
@@ -2405,12 +2413,17 @@ class _RenderAlertDialogActionsLayout extends RenderFlex {
     final double height = getMinIntrinsicHeight(overallWidth);
     size = Size(overallWidth, height);
 
+    final bool ltr = textDirection == TextDirection.ltr;
     RenderBox slot = firstChild!;
-    double x = 0;
+    double x = ltr ? 0 : (overallWidth - slotWidth);
     while (true) {
       slot.layout(BoxConstraints.tight(Size(slotWidth, height)), parentUsesSize: true);
       (slot.parentData! as FlexParentData).offset = Offset(x, 0);
-      x += slot.size.width;
+      if (ltr) {
+        x += slot.size.width;
+      } else {
+        x -= slot.size.width;
+      }
 
       final RenderBox? divider = childAfter(slot);
       if (divider == null) {
@@ -2418,8 +2431,11 @@ class _RenderAlertDialogActionsLayout extends RenderFlex {
       }
       divider.layout(BoxConstraints.tight(Size(dividerThickness, height)));
       (divider.parentData! as FlexParentData).offset = Offset(x, 0);
-      x += dividerThickness;
-
+      if (ltr) {
+        x += dividerThickness;
+      } else {
+        x -= dividerThickness;
+      }
       slot = childAfter(divider)!;
     }
   }

packages/flutter/test/cupertino/dialog_test.dart

@@ -2036,6 +2036,33 @@ void main() {
 
     expect(elements.length, 1, reason: 'No DecoratedBox matches the specified criteria.');
   });
+
+  testWidgets('Check for Directionality', (WidgetTester tester) async {
+    Future<void> pumpWidget({required bool isLTR}) async {
+      await tester.pumpWidget(
+        CupertinoApp(
+          home: Directionality(
+            textDirection: isLTR ? TextDirection.ltr : TextDirection.rtl,
+            child: const CupertinoAlertDialog(
+              actions: <CupertinoDialogAction>[
+                CupertinoDialogAction(isDefaultAction: true, child: Text('No')),
+                CupertinoDialogAction(child: Text('Yes')),
+              ],
+            ),
+          ),
+        ),
+      );
+    }
+
+    await pumpWidget(isLTR: true);
+    Offset yesButton = tester.getCenter(find.text('Yes'));
+    Offset noButton = tester.getCenter(find.text('No'));
+    expect(yesButton.dx > noButton.dx, true);
+    await pumpWidget(isLTR: false);
+    yesButton = tester.getCenter(find.text('Yes'));
+    noButton = tester.getCenter(find.text('No'));
+    expect(yesButton.dx > noButton.dx, false);
+  });
 }
 
 RenderBox findActionButtonRenderBoxByTitle(WidgetTester tester, String title) {
@@ -2124,6 +2151,7 @@ class _RestorableDialogTestWidget extends StatelessWidget {
 // The `theme` will be applied to the app and determines the background.
 class TestScaffoldApp extends StatefulWidget {
   const TestScaffoldApp({super.key, required this.theme, required this.dialog});
+
   final CupertinoThemeData theme;
   final Widget dialog;