expose clipBehavior (#74046)

packages/flutter/lib/src/widgets/animated_list.dart

@@ -276,6 +276,7 @@ class AnimatedList extends StatefulWidget {
     this.physics,
     this.shrinkWrap = false,
     this.padding,
+    this.clipBehavior = Clip.hardEdge,
   }) : assert(itemBuilder != null),
        assert(initialItemCount != null && initialItemCount >= 0),
        super(key: key);
@@ -373,6 +374,11 @@ class AnimatedList extends StatefulWidget {
   /// The amount of space by which to inset the children.
   final EdgeInsetsGeometry? padding;
 
+  /// {@macro flutter.material.Material.clipBehavior}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   /// The state from the closest instance of this class that encloses the given
   /// context.
   ///
@@ -493,6 +499,7 @@ class AnimatedListState extends State<AnimatedList> with TickerProviderStateMixi
       primary: widget.primary,
       physics: widget.physics,
       shrinkWrap: widget.shrinkWrap,
+      clipBehavior: widget.clipBehavior,
       slivers: <Widget>[
         SliverPadding(
           padding: widget.padding ?? EdgeInsets.zero,

packages/flutter/test/widgets/animated_list_test.dart

@@ -363,4 +363,28 @@ void main() {
       ),
     );
   });
+
+  testWidgets('AnimatedList.clipBehavior is forwarded to its inner CustomScrollView', (WidgetTester tester) async {
+  const Clip clipBehavior = Clip.none;
+
+    await tester.pumpWidget(
+      Directionality(
+        textDirection: TextDirection.ltr,
+        child: AnimatedList(
+          initialItemCount: 2,
+          clipBehavior: clipBehavior,
+          itemBuilder: (BuildContext context, int index, Animation<double> _) {
+            return SizedBox(
+              height: 100.0,
+              child: Center(
+                child: Text('item $index'),
+              ),
+            );
+          },
+        ),
+      ),
+    );
+
+    expect(tester.widget<CustomScrollView>(find.byType(CustomScrollView)).clipBehavior, clipBehavior);
+  });
 }