feat: import Chinese-localized Buzz source snapshot

Signed-off-by: cls_宁波本机 <908705107@qq.com>

mobile/test/shared/widgets/modal_presentation_test.dart

@@ -0,0 +1,226 @@
+import 'package:buzz/shared/widgets/concentric_sheet_surface.dart';
+import 'package:buzz/shared/theme/theme.dart';
+import 'package:buzz/shared/widgets/modal_presentation.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets(
+    'keeps an opaque Flutter surface when iOS native support is unavailable',
+    (tester) async {
+      debugDefaultTargetPlatformOverride = TargetPlatform.iOS;
+      try {
+        await tester.pumpWidget(
+          MaterialApp(
+            theme: AppTheme.light(),
+            home: const ConcentricSheetSurface(
+              enabled: true,
+              color: Colors.red,
+              child: SizedBox(height: 80, child: Text('Sheet body')),
+            ),
+          ),
+        );
+        await tester.pumpAndSettle();
+
+        expect(
+          find.byWidgetPredicate(
+            (widget) => widget is Material && widget.color == Colors.red,
+          ),
+          findsOneWidget,
+        );
+      } finally {
+        debugDefaultTargetPlatformOverride = null;
+      }
+    },
+  );
+
+  testWidgets(
+    'replaces the Flutter fallback when native support is available',
+    (tester) async {
+      debugDefaultTargetPlatformOverride = TargetPlatform.iOS;
+      const surfaceChannel = MethodChannel('buzz/concentric_sheet_surface');
+      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+        surfaceChannel,
+        (call) async => call.method == 'isSupported' ? true : null,
+      );
+      try {
+        await tester.pumpWidget(
+          MaterialApp(
+            theme: AppTheme.light(),
+            home: const ConcentricSheetSurface(
+              enabled: true,
+              color: Colors.red,
+              child: SizedBox(height: 80, child: Text('Sheet body')),
+            ),
+          ),
+        );
+        await tester.pump();
+
+        expect(find.byType(UiKitView), findsOneWidget);
+        expect(
+          find.byWidgetPredicate(
+            (widget) => widget is Material && widget.color == Colors.red,
+          ),
+          findsNothing,
+        );
+      } finally {
+        tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+          surfaceChannel,
+          null,
+        );
+        debugDefaultTargetPlatformOverride = null;
+      }
+    },
+  );
+
+  testWidgets(
+    'non-iOS sheets use Flutter drag handle and shared close control',
+    (tester) async {
+      debugDefaultTargetPlatformOverride = TargetPlatform.android;
+      try {
+        await tester.pumpWidget(
+          MaterialApp(
+            theme: AppTheme.light(),
+            home: Scaffold(
+              body: Builder(
+                builder: (context) => FilledButton(
+                  onPressed: () => showBuzzModalBottomSheet<void>(
+                    context: context,
+                    showDragHandle: true,
+                    builder: (_) => const Text('Sheet body'),
+                  ),
+                  child: const Text('Open sheet'),
+                ),
+              ),
+            ),
+          ),
+        );
+
+        await tester.tap(find.text('Open sheet'));
+        await tester.pumpAndSettle();
+
+        final closeButton = find.byTooltip('Close sheet');
+        expect(closeButton, findsOneWidget);
+        expect(tester.getSize(closeButton), const Size.square(44));
+        final closeGutter = find.ancestor(
+          of: closeButton,
+          matching: find.byWidgetPredicate(
+            (widget) =>
+                widget is Padding &&
+                widget.padding ==
+                    const EdgeInsets.only(
+                      top: Grid.xxs,
+                      left: Grid.gutter,
+                      right: Grid.gutter,
+                      bottom: Grid.xs,
+                    ),
+          ),
+        );
+        expect(closeGutter, findsOneWidget);
+        final gutterRect = tester.getRect(closeGutter);
+        final closeRect = tester.getRect(closeButton);
+        expect(closeRect.top - gutterRect.top, Grid.gutter);
+        expect(gutterRect.right - closeRect.right, Grid.gutter);
+        expect(
+          tester.widget<BottomSheet>(find.byType(BottomSheet)).showDragHandle,
+          isTrue,
+        );
+        expect(
+          find.byKey(const ValueKey('buzz-sheet-drag-handle')),
+          findsNothing,
+        );
+        expect(find.text('Sheet body'), findsOneWidget);
+
+        await tester.tap(closeButton);
+        await tester.pumpAndSettle();
+
+        expect(find.text('Sheet body'), findsNothing);
+      } finally {
+        debugDefaultTargetPlatformOverride = null;
+      }
+    },
+  );
+
+  testWidgets('iOS paints the drag handle inside the concentric surface', (
+    tester,
+  ) async {
+    debugDefaultTargetPlatformOverride = TargetPlatform.iOS;
+    try {
+      await tester.pumpWidget(
+        MaterialApp(
+          theme: AppTheme.light(),
+          home: Scaffold(
+            body: Builder(
+              builder: (context) => FilledButton(
+                onPressed: () => showBuzzModalBottomSheet<void>(
+                  context: context,
+                  showDragHandle: true,
+                  builder: (_) => const Text('Sheet body'),
+                ),
+                child: const Text('Open sheet'),
+              ),
+            ),
+          ),
+        ),
+      );
+
+      await tester.tap(find.text('Open sheet'));
+      await tester.pumpAndSettle();
+
+      expect(
+        tester.widget<BottomSheet>(find.byType(BottomSheet)).showDragHandle,
+        isFalse,
+      );
+      final internalHandle = find.byKey(
+        const ValueKey('buzz-sheet-drag-handle'),
+      );
+      expect(internalHandle, findsOneWidget);
+      expect(tester.getSize(internalHandle), const Size(32, 4));
+      expect(find.bySemanticsLabel('Drag handle'), findsOneWidget);
+      expect(find.byTooltip('Close sheet'), findsOneWidget);
+      expect(find.text('Sheet body'), findsOneWidget);
+    } finally {
+      debugDefaultTargetPlatformOverride = null;
+    }
+  });
+
+  testWidgets('iOS compact sheets can omit X but retain the inside handle', (
+    tester,
+  ) async {
+    debugDefaultTargetPlatformOverride = TargetPlatform.iOS;
+    try {
+      await tester.pumpWidget(
+        MaterialApp(
+          theme: AppTheme.light(),
+          home: Scaffold(
+            body: Builder(
+              builder: (context) => FilledButton(
+                onPressed: () => showBuzzModalBottomSheet<void>(
+                  context: context,
+                  showDragHandle: true,
+                  showCloseButton: false,
+                  builder: (_) => const Text('Compact sheet body'),
+                ),
+                child: const Text('Open compact sheet'),
+              ),
+            ),
+          ),
+        ),
+      );
+
+      await tester.tap(find.text('Open compact sheet'));
+      await tester.pumpAndSettle();
+
+      expect(
+        find.byKey(const ValueKey('buzz-sheet-drag-handle')),
+        findsOneWidget,
+      );
+      expect(find.byTooltip('Close sheet'), findsNothing);
+      expect(find.text('Compact sheet body'), findsOneWidget);
+    } finally {
+      debugDefaultTargetPlatformOverride = null;
+    }
+  });
+}