More missing clipBehavior respects (#103931)

Author: dnfield

packages/flutter/lib/src/rendering/editable.dart

@@ -2526,7 +2526,16 @@ class RenderEditable extends RenderBox with RelayoutWhenSystemFontsChangeMixin,
   final LayerHandle<ClipRectLayer> _clipRectLayer = LayerHandle<ClipRectLayer>();
 
   @override
-  Rect? describeApproximatePaintClip(RenderObject child) => _hasVisualOverflow ? Offset.zero & size : null;
+  Rect? describeApproximatePaintClip(RenderObject child) {
+    switch (clipBehavior) {
+      case Clip.none:
+        return null;
+      case Clip.hardEdge:
+      case Clip.antiAlias:
+      case Clip.antiAliasWithSaveLayer:
+        return _hasVisualOverflow ? Offset.zero & size : null;
+    }
+  }
 
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {

packages/flutter/lib/src/rendering/flex.dart

@@ -1144,7 +1144,17 @@ class RenderFlex extends RenderBox with ContainerRenderObjectMixin<RenderBox, Fl
   }
 
   @override
-  Rect? describeApproximatePaintClip(RenderObject child) => _hasOverflow ? Offset.zero & size : null;
+  Rect? describeApproximatePaintClip(RenderObject child) {
+    switch (clipBehavior) {
+      case Clip.none:
+        return null;
+      case Clip.hardEdge:
+      case Clip.antiAlias:
+      case Clip.antiAliasWithSaveLayer:
+        return _hasOverflow ? Offset.zero & size : null;
+    }
+  }
+
 
   @override
   String toStringShort() {

packages/flutter/lib/src/rendering/object.dart

@@ -2788,6 +2788,11 @@ abstract class RenderObject extends AbstractNode with DiagnosticableTreeMixin im
   ///
   /// This is used in the semantics phase to avoid including children
   /// that are not physically visible.
+  ///
+  /// RenderObjects that respect a [Clip] behavior when painting _must_ respect
+  /// that same behavior when describing this value. For example, if passing
+  /// [Clip.none] to [PaintingContext.pushClipRect] as the `clipBehavior`, then
+  /// the implementation of this method must return null.
   Rect? describeApproximatePaintClip(covariant RenderObject child) => null;
 
   /// Returns a rect in this object's coordinate system that describes

packages/flutter/lib/src/rendering/shifted_box.dart

@@ -826,7 +826,14 @@ class RenderConstraintsTransformBox extends RenderAligningShiftedBox with DebugO
 
   @override
   Rect? describeApproximatePaintClip(RenderObject child) {
-    return _isOverflowing ? Offset.zero & size : null;
+    switch (clipBehavior) {
+      case Clip.none:
+        return null;
+      case Clip.hardEdge:
+      case Clip.antiAlias:
+      case Clip.antiAliasWithSaveLayer:
+        return _isOverflowing ? Offset.zero & size : null;
+    }
   }
 
   @override

packages/flutter/lib/src/rendering/stack.dart

@@ -636,7 +636,16 @@ class RenderStack extends RenderBox
   }
 
   @override
-  Rect? describeApproximatePaintClip(RenderObject child) => _hasVisualOverflow ? Offset.zero & size : null;
+  Rect? describeApproximatePaintClip(RenderObject child) {
+    switch (clipBehavior) {
+      case Clip.none:
+        return null;
+      case Clip.hardEdge:
+      case Clip.antiAlias:
+      case Clip.antiAliasWithSaveLayer:
+        return _hasVisualOverflow ? Offset.zero & size : null;
+    }
+  }
 
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {

packages/flutter/lib/src/rendering/viewport.dart

@@ -562,7 +562,16 @@ abstract class RenderViewportBase<ParentDataClass extends ContainerParentDataMix
   }
 
   @override
-  Rect describeApproximatePaintClip(RenderSliver child) {
+  Rect? describeApproximatePaintClip(RenderSliver child) {
+    switch (clipBehavior) {
+      case Clip.none:
+        return null;
+      case Clip.hardEdge:
+      case Clip.antiAlias:
+      case Clip.antiAliasWithSaveLayer:
+        break;
+    }
+
     final Rect viewportClip = Offset.zero & size;
     // The child's viewportMainAxisExtent can be infinite when a
     // RenderShrinkWrappingViewport is given infinite constraints, such as when

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

@@ -866,7 +866,16 @@ class _RenderTheatre extends RenderBox with ContainerRenderObjectMixin<RenderBox
   }
 
   @override
-  Rect? describeApproximatePaintClip(RenderObject child) => _hasVisualOverflow ? Offset.zero & size : null;
+  Rect? describeApproximatePaintClip(RenderObject child) {
+    switch (clipBehavior) {
+      case Clip.none:
+        return null;
+      case Clip.hardEdge:
+      case Clip.antiAlias:
+      case Clip.antiAliasWithSaveLayer:
+        return _hasVisualOverflow ? Offset.zero & size : null;
+    }
+  }
 
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {

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

@@ -533,10 +533,17 @@ class _RenderSingleChildViewport extends RenderBox with RenderObjectWithChildMix
 
   bool _shouldClipAtPaintOffset(Offset paintOffset) {
     assert(child != null);
-    return paintOffset.dx < 0 ||
-      paintOffset.dy < 0 ||
-      paintOffset.dx + child!.size.width > size.width ||
-      paintOffset.dy + child!.size.height > size.height;
+    switch (clipBehavior) {
+      case Clip.none:
+        return false;
+      case Clip.hardEdge:
+      case Clip.antiAlias:
+      case Clip.antiAliasWithSaveLayer:
+        return paintOffset.dx < 0 ||
+               paintOffset.dy < 0 ||
+               paintOffset.dx + child!.size.width > size.width ||
+               paintOffset.dy + child!.size.height > size.height;
+    }
   }
 
   @override
@@ -548,7 +555,7 @@ class _RenderSingleChildViewport extends RenderBox with RenderObjectWithChildMix
         context.paintChild(child!, offset + paintOffset);
       }
 
-      if (_shouldClipAtPaintOffset(paintOffset) && clipBehavior != Clip.none) {
+      if (_shouldClipAtPaintOffset(paintOffset)) {
         _clipRectLayer.layer = context.pushClipRect(
           needsCompositing,
           offset,

packages/flutter/test/rendering/editable_test.dart

@@ -128,6 +128,28 @@ void main() {
     }
   });
 
+  test('Editable respect clipBehavior in describeApproximatePaintClip', () {
+    final String longString = 'a' * 10000;
+    final RenderEditable editable = RenderEditable(
+      text: TextSpan(text: longString),
+      textDirection: TextDirection.ltr,
+      startHandleLayerLink: LayerLink(),
+      endHandleLayerLink: LayerLink(),
+      offset: ViewportOffset.zero(),
+      textSelectionDelegate: _FakeEditableTextState(),
+      selection: const TextSelection(baseOffset: 0, extentOffset: 0),
+      clipBehavior: Clip.none,
+    );
+    layout(editable);
+
+    bool visited = false;
+    editable.visitChildren((RenderObject child) {
+      visited = true;
+      expect(editable.describeApproximatePaintClip(child), null);
+    });
+    expect(visited, true);
+  });
+
   test('editable intrinsics', () {
     final TextSelectionDelegate delegate = _FakeEditableTextState();
     final RenderEditable editable = RenderEditable(

packages/flutter/test/rendering/viewport_test.dart

@@ -2158,4 +2158,41 @@ void main() {
     await tester.drag(find.text('b'), const Offset(0, 200));
     await tester.pumpAndSettle();
   }, variant: const TargetPlatformVariant(<TargetPlatform>{ TargetPlatform.iOS, TargetPlatform.macOS }));
+
+  testWidgets('Viewport describeApproximateClip respects clipBehavior', (WidgetTester tester) async {
+    await tester.pumpWidget(const Directionality(
+      textDirection: TextDirection.ltr,
+      child: CustomScrollView(
+        clipBehavior: Clip.none,
+        slivers: <Widget>[
+          SliverToBoxAdapter(child: SizedBox(width: 20, height: 20)),
+        ]
+      ),
+    ));
+    RenderViewport viewport = tester.allRenderObjects.whereType<RenderViewport>().first;
+    expect(viewport.clipBehavior, Clip.none);
+    bool visited = false;
+    viewport.visitChildren((RenderObject child) {
+      visited = true;
+      expect(viewport.describeApproximatePaintClip(child as RenderSliver), null);
+    });
+    expect(visited, true);
+
+    await tester.pumpWidget(const Directionality(
+      textDirection: TextDirection.ltr,
+      child: CustomScrollView(
+        slivers: <Widget>[
+          SliverToBoxAdapter(child: SizedBox(width: 20, height: 20)),
+        ]
+      ),
+    ));
+    viewport = tester.allRenderObjects.whereType<RenderViewport>().first;
+    expect(viewport.clipBehavior, Clip.hardEdge);
+    visited = false;
+    viewport.visitChildren((RenderObject child) {
+      visited = true;
+      expect(viewport.describeApproximatePaintClip(child as RenderSliver), Offset.zero & viewport.size);
+    });
+    expect(visited, true);
+  });
 }