Added clipBehavior on TabBarView (#103166)

Author: QuncCccccc

packages/flutter/lib/src/material/tabs.dart

@@ -1310,6 +1310,7 @@ class TabBarView extends StatefulWidget {
     this.physics,
     this.dragStartBehavior = DragStartBehavior.start,
     this.viewportFraction = 1.0,
+    this.clipBehavior = Clip.hardEdge,
   }) : assert(children != null),
        assert(dragStartBehavior != null);
 
@@ -1342,6 +1343,11 @@ class TabBarView extends StatefulWidget {
   /// {@macro flutter.widgets.pageview.viewportFraction}
   final double viewportFraction;
 
+  /// {@macro flutter.material.Material.clipBehavior}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   @override
   State<TabBarView> createState() => _TabBarViewState();
 }
@@ -1531,6 +1537,7 @@ class _TabBarViewState extends State<TabBarView> {
       onNotification: _handleScrollNotification,
       child: PageView(
         dragStartBehavior: widget.dragStartBehavior,
+        clipBehavior: widget.clipBehavior,
         controller: _pageController,
         physics: widget.physics == null
           ? const PageScrollPhysics().applyTo(const ClampingScrollPhysics())

packages/flutter/test/material/tabs_test.dart

@@ -1104,6 +1104,45 @@ void main() {
     expect(pageController.viewportFraction, 1);
   });
 
+  testWidgets('TabBarView has clipBehavior Clip.hardEdge by default', (WidgetTester tester) async {
+    final List<Widget> tabs = <Widget>[const Text('First'), const Text('Second')];
+
+    Widget builder() {
+      return boilerplate(
+        child: DefaultTabController(
+          length: tabs.length,
+          child: TabBarView(
+            children: tabs,
+          ),
+        ),
+      );
+    }
+
+    await tester.pumpWidget(builder());
+    final TabBarView tabBarView = tester.widget(find.byType(TabBarView));
+    expect(tabBarView.clipBehavior, Clip.hardEdge);
+  });
+
+  testWidgets('TabBarView sets clipBehavior correctly', (WidgetTester tester) async {
+    final List<Widget> tabs = <Widget>[const Text('First'), const Text('Second')];
+
+    Widget builder() {
+      return boilerplate(
+        child: DefaultTabController(
+          length: tabs.length,
+          child: TabBarView(
+            clipBehavior: Clip.none,
+            children: tabs,
+          ),
+        ),
+      );
+    }
+
+    await tester.pumpWidget(builder());
+    final PageView pageView = tester.widget(find.byType(PageView));
+    expect(pageView.clipBehavior, Clip.none);
+  });
+
   testWidgets('TabBar tap skips indicator animation when disabled in controller', (WidgetTester tester) async {
     final List<String> tabs = <String>['A', 'B'];