Reland non-breaking "Add clipBehavior to widgets with clipRect #55977" (#59364)

* Revert "Revert "Add clipBehavior to widgets with clipRect (#55977)" (#58344)"

This reverts commit 1d395c5e.

* Add missed Overflow

dev/integration_tests/flutter_gallery/lib/demo/pesto_demo.dart

@@ -224,7 +224,7 @@ class _PestoLogoState extends State<PestoLogo> {
         child: SizedBox(
           width: kLogoWidth,
           child: Stack(
-            overflow: Overflow.visible,
+            clipBehavior: Clip.none,
             children: <Widget>[
               Positioned.fromRect(
                 rect: _imageRectTween.lerp(widget.t),

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

@@ -230,6 +230,7 @@ class RenderEditable extends RenderBox with RelayoutWhenSystemFontsChangeMixin {
     EdgeInsets floatingCursorAddedMargin = const EdgeInsets.fromLTRB(4, 4, 4, 5),
     TextRange promptRectRange,
     Color promptRectColor,
+    Clip clipBehavior = Clip.hardEdge,
     @required this.textSelectionDelegate,
   }) : assert(textAlign != null),
        assert(textDirection != null, 'RenderEditable created without a textDirection.'),
@@ -260,6 +261,7 @@ class RenderEditable extends RenderBox with RelayoutWhenSystemFontsChangeMixin {
        assert(devicePixelRatio != null),
        assert(selectionHeightStyle != null),
        assert(selectionWidthStyle != null),
+       assert(clipBehavior != null),
        _textPainter = TextPainter(
          text: text,
          textAlign: textAlign,
@@ -294,7 +296,8 @@ class RenderEditable extends RenderBox with RelayoutWhenSystemFontsChangeMixin {
        _obscureText = obscureText,
        _readOnly = readOnly,
        _forceLine = forceLine,
-       _promptRectRange = promptRectRange {
+       _promptRectRange = promptRectRange,
+       _clipBehavior = clipBehavior {
     assert(_showCursor != null);
     assert(!_showCursor.value || cursorColor != null);
     this.hasFocus = hasFocus ?? false;
@@ -1254,6 +1257,20 @@ class RenderEditable extends RenderBox with RelayoutWhenSystemFontsChangeMixin {
 
   double get _caretMargin => _kCaretGap + cursorWidth;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge], and must not be null.
+  Clip get clipBehavior => _clipBehavior;
+  Clip _clipBehavior = Clip.hardEdge;
+  set clipBehavior(Clip value) {
+    assert(value != null);
+    if (value != _clipBehavior) {
+      _clipBehavior = value;
+      markNeedsPaint();
+      markNeedsSemanticsUpdate();
+    }
+  }
+
   @override
   void describeSemanticsConfiguration(SemanticsConfiguration config) {
     super.describeSemanticsConfiguration(config);
@@ -2148,8 +2165,8 @@ class RenderEditable extends RenderBox with RelayoutWhenSystemFontsChangeMixin {
   @override
   void paint(PaintingContext context, Offset offset) {
     _layoutText(minWidth: constraints.minWidth, maxWidth: constraints.maxWidth);
-    if (_hasVisualOverflow)
-      context.pushClipRect(needsCompositing, offset, Offset.zero & size, _paintContents);
+    if (_hasVisualOverflow && clipBehavior != Clip.none)
+      context.pushClipRect(needsCompositing, offset, Offset.zero & size, _paintContents, clipBehavior: clipBehavior);
     else
       _paintContents(context, offset);
     _paintHandleLayers(context, getEndpointsForSelection(selection));

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

@@ -279,17 +279,20 @@ class RenderFlex extends RenderBox with ContainerRenderObjectMixin<RenderBox, Fl
     TextDirection textDirection,
     VerticalDirection verticalDirection = VerticalDirection.down,
     TextBaseline textBaseline,
+    Clip clipBehavior = Clip.none,
   }) : assert(direction != null),
        assert(mainAxisAlignment != null),
        assert(mainAxisSize != null),
        assert(crossAxisAlignment != null),
+       assert(clipBehavior != null),
        _direction = direction,
        _mainAxisAlignment = mainAxisAlignment,
        _mainAxisSize = mainAxisSize,
        _crossAxisAlignment = crossAxisAlignment,
        _textDirection = textDirection,
        _verticalDirection = verticalDirection,
-       _textBaseline = textBaseline {
+       _textBaseline = textBaseline,
+       _clipBehavior = clipBehavior {
     addAll(children);
   }
 
@@ -476,6 +479,20 @@ class RenderFlex extends RenderBox with ContainerRenderObjectMixin<RenderBox, Fl
   // are treated as not overflowing.
   bool get _hasOverflow => _overflow > precisionErrorTolerance;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.none], and must not be null.
+  Clip get clipBehavior => _clipBehavior;
+  Clip _clipBehavior = Clip.none;
+  set clipBehavior(Clip value) {
+    assert(value != null);
+    if (value != _clipBehavior) {
+      _clipBehavior = value;
+      markNeedsPaint();
+      markNeedsSemanticsUpdate();
+    }
+  }
+
   @override
   void setupParentData(RenderBox child) {
     if (child.parentData is! FlexParentData)
@@ -957,8 +974,12 @@ class RenderFlex extends RenderBox with ContainerRenderObjectMixin<RenderBox, Fl
     if (size.isEmpty)
       return;
 
-    // We have overflow. Clip it.
-    context.pushClipRect(needsCompositing, offset, Offset.zero & size, defaultPaint);
+    if (clipBehavior == Clip.none) {
+      defaultPaint(context, offset);
+    } else {
+      // We have overflow and the clipBehavior isn't none. Clip it.
+      context.pushClipRect(needsCompositing, offset, Offset.zero & size, defaultPaint, clipBehavior: clipBehavior);
+    }
 
     assert(() {
       // Only set this if it's null to save work. It gets reset to null if the

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

@@ -145,8 +145,8 @@ class RenderListWheelViewport
     double overAndUnderCenterOpacity = 1,
     @required double itemExtent,
     double squeeze = 1,
-    bool clipToSize = true,
     bool renderChildrenOutsideViewport = false,
+    Clip clipBehavior = Clip.none,
     List<RenderBox> children,
   }) : assert(childManager != null),
        assert(offset != null),
@@ -165,11 +165,11 @@ class RenderListWheelViewport
        assert(squeeze != null),
        assert(squeeze > 0),
        assert(itemExtent > 0),
-       assert(clipToSize != null),
        assert(renderChildrenOutsideViewport != null),
+       assert(clipBehavior != null),
        assert(
-         !renderChildrenOutsideViewport || !clipToSize,
-         clipToSizeAndRenderChildrenOutsideViewportConflict,
+         !renderChildrenOutsideViewport || clipBehavior == Clip.none,
+         clipBehaviorAndRenderChildrenOutsideViewportConflict,
        ),
        _offset = offset,
        _diameterRatio = diameterRatio,
@@ -180,8 +180,8 @@ class RenderListWheelViewport
        _overAndUnderCenterOpacity = overAndUnderCenterOpacity,
        _itemExtent = itemExtent,
        _squeeze = squeeze,
-       _clipToSize = clipToSize,
-       _renderChildrenOutsideViewport = renderChildrenOutsideViewport {
+       _renderChildrenOutsideViewport = renderChildrenOutsideViewport,
+       _clipBehavior = clipBehavior {
     addAll(children);
   }
 
@@ -201,10 +201,10 @@ class RenderListWheelViewport
       'be clipped in the z-axis and therefore not renderable. Value must be '
       'between 0 and 0.01.';
 
-  /// An error message to show when [clipToSize] and [renderChildrenOutsideViewport]
+  /// An error message to show when [clipBehavior] and [renderChildrenOutsideViewport]
   /// are set to conflicting values.
-  static const String clipToSizeAndRenderChildrenOutsideViewportConflict =
-      'Cannot renderChildrenOutsideViewport and clipToSize since children '
+  static const String clipBehaviorAndRenderChildrenOutsideViewportConflict =
+      'Cannot renderChildrenOutsideViewport and clip since children '
       'rendered outside will be clipped anyway.';
 
   /// The delegate that manages the children of this object.
@@ -443,37 +443,14 @@ class RenderListWheelViewport
     markNeedsSemanticsUpdate();
   }
 
-  /// {@template flutter.rendering.wheelList.clipToSize}
-  /// Whether to clip painted children to the inside of this viewport.
-  ///
-  /// Defaults to [true]. Must not be null.
-  ///
-  /// If this is false and [renderChildrenOutsideViewport] is false, the
-  /// first and last children may be painted partly outside of this scroll view.
-  /// {@endtemplate}
-  bool get clipToSize => _clipToSize;
-  bool _clipToSize;
-  set clipToSize(bool value) {
-    assert(value != null);
-    assert(
-      !renderChildrenOutsideViewport || !clipToSize,
-      clipToSizeAndRenderChildrenOutsideViewportConflict,
-    );
-    if (value == _clipToSize)
-      return;
-    _clipToSize = value;
-    markNeedsPaint();
-    markNeedsSemanticsUpdate();
-  }
-
   /// {@template flutter.rendering.wheelList.renderChildrenOutsideViewport}
   /// Whether to paint children inside the viewport only.
   ///
   /// If false, every child will be painted. However the [Scrollable] is still
   /// the size of the viewport and detects gestures inside only.
   ///
-  /// Defaults to [false]. Must not be null. Cannot be true if [clipToSize]
-  /// is also true since children outside the viewport will be clipped, and
+  /// Defaults to [false]. Must not be null. Cannot be true if [clipBehavior]
+  /// is not [Clip.none] since children outside the viewport will be clipped, and
   /// therefore cannot render children outside the viewport.
   /// {@endtemplate}
   bool get renderChildrenOutsideViewport => _renderChildrenOutsideViewport;
@@ -481,8 +458,8 @@ class RenderListWheelViewport
   set renderChildrenOutsideViewport(bool value) {
     assert(value != null);
     assert(
-      !renderChildrenOutsideViewport || !clipToSize,
-      clipToSizeAndRenderChildrenOutsideViewportConflict,
+      !renderChildrenOutsideViewport || clipBehavior == Clip.none,
+      clipBehaviorAndRenderChildrenOutsideViewportConflict,
     );
     if (value == _renderChildrenOutsideViewport)
       return;
@@ -491,6 +468,20 @@ class RenderListWheelViewport
     markNeedsSemanticsUpdate();
   }
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge], and must not be null.
+  Clip get clipBehavior => _clipBehavior;
+  Clip _clipBehavior = Clip.hardEdge;
+  set clipBehavior(Clip value) {
+    assert(value != null);
+    if (value != _clipBehavior) {
+      _clipBehavior = value;
+      markNeedsPaint();
+      markNeedsSemanticsUpdate();
+    }
+  }
+
   void _hasScrolled() {
     markNeedsLayout();
     markNeedsSemanticsUpdate();
@@ -789,12 +780,13 @@ class RenderListWheelViewport
   @override
   void paint(PaintingContext context, Offset offset) {
     if (childCount > 0) {
-      if (_clipToSize && _shouldClipAtCurrentOffset()) {
+      if (_shouldClipAtCurrentOffset() && clipBehavior != Clip.none) {
         context.pushClipRect(
           needsCompositing,
           offset,
           Offset.zero & size,
           _paintVisibleChildren,
+          clipBehavior: clipBehavior,
         );
       } else {
         _paintVisibleChildren(context, offset);

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

@@ -2294,11 +2294,14 @@ class RenderFittedBox extends RenderProxyBox {
     AlignmentGeometry alignment = Alignment.center,
     TextDirection textDirection,
     RenderBox child,
+    Clip clipBehavior = Clip.none,
   }) : assert(fit != null),
        assert(alignment != null),
+       assert(clipBehavior != null),
        _fit = fit,
        _alignment = alignment,
        _textDirection = textDirection,
+       _clipBehavior = clipBehavior,
        super(child);
 
   Alignment _resolvedAlignment;
@@ -2375,6 +2378,20 @@ class RenderFittedBox extends RenderProxyBox {
   bool _hasVisualOverflow;
   Matrix4 _transform;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.none], and must not be null.
+  Clip get clipBehavior => _clipBehavior;
+  Clip _clipBehavior = Clip.none;
+  set clipBehavior(Clip value) {
+    assert(value != null);
+    if (value != _clipBehavior) {
+      _clipBehavior = value;
+      markNeedsPaint();
+      markNeedsSemanticsUpdate();
+    }
+  }
+
   void _clearPaintData() {
     _hasVisualOverflow = null;
     _transform = null;
@@ -2420,9 +2437,9 @@ class RenderFittedBox extends RenderProxyBox {
       return;
     _updatePaintData();
     if (child != null) {
-      if (_hasVisualOverflow)
+      if (_hasVisualOverflow && clipBehavior != Clip.none)
         layer = context.pushClipRect(needsCompositing, offset, Offset.zero & size, _paintChildWithTransform,
-            oldLayer: layer is ClipRectLayer ? layer as ClipRectLayer : null);
+            oldLayer: layer is ClipRectLayer ? layer as ClipRectLayer : null, clipBehavior: clipBehavior);
       else
         layer = _paintChildWithTransform(context, offset);
     }

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

@@ -628,8 +628,11 @@ class RenderUnconstrainedBox extends RenderAligningShiftedBox with DebugOverflow
     @required TextDirection textDirection,
     Axis constrainedAxis,
     RenderBox child,
+    Clip clipBehavior = Clip.none,
   }) : assert(alignment != null),
+       assert(clipBehavior != null),
        _constrainedAxis = constrainedAxis,
+       _clipBehavior = clipBehavior,
        super.mixin(alignment, textDirection, child);
 
   /// The axis to retain constraints on, if any.
@@ -651,6 +654,20 @@ class RenderUnconstrainedBox extends RenderAligningShiftedBox with DebugOverflow
   Rect _overflowChildRect = Rect.zero;
   bool _isOverflowing = false;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.none], and must not be null.
+  Clip get clipBehavior => _clipBehavior;
+  Clip _clipBehavior = Clip.none;
+  set clipBehavior(Clip value) {
+    assert(value != null);
+    if (value != _clipBehavior) {
+      _clipBehavior = value;
+      markNeedsPaint();
+      markNeedsSemanticsUpdate();
+    }
+  }
+
   @override
   void performLayout() {
     final BoxConstraints constraints = this.constraints;
@@ -696,8 +713,12 @@ class RenderUnconstrainedBox extends RenderAligningShiftedBox with DebugOverflow
       return;
     }
 
-    // We have overflow. Clip it.
-    context.pushClipRect(needsCompositing, offset, Offset.zero & size, super.paint);
+    if (clipBehavior == Clip.none) {
+      super.paint(context, offset);
+    } else {
+      // We have overflow and the clipBehavior isn't none. Clip it.
+      context.pushClipRect(needsCompositing, offset, Offset.zero & size, super.paint, clipBehavior: clipBehavior);
+    }
 
     // Display the overflow indicator.
     assert(() {

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

@@ -270,6 +270,8 @@ enum StackFit {
   passthrough,
 }
 
+// TODO(liyuqian): Deprecate and remove `Overflow` once its usages are removed from Google.
+
 /// Whether overflowing children should be clipped, or their overflow be
 /// visible.
 enum Overflow {
@@ -328,14 +330,14 @@ class RenderStack extends RenderBox
     AlignmentGeometry alignment = AlignmentDirectional.topStart,
     TextDirection textDirection,
     StackFit fit = StackFit.loose,
-    Overflow overflow = Overflow.clip,
+    Clip clipBehavior = Clip.hardEdge,
   }) : assert(alignment != null),
        assert(fit != null),
-       assert(overflow != null),
+       assert(clipBehavior != null),
        _alignment = alignment,
        _textDirection = textDirection,
        _fit = fit,
-       _overflow = overflow {
+       _clipBehavior = clipBehavior {
     addAll(children);
   }
 
@@ -413,17 +415,17 @@ class RenderStack extends RenderBox
     }
   }
 
-  /// Whether overflowing children should be clipped. See [Overflow].
+  /// {@macro flutter.widgets.Clip}
   ///
-  /// Some children in a stack might overflow its box. When this flag is set to
-  /// [Overflow.clip], children cannot paint outside of the stack's box.
-  Overflow get overflow => _overflow;
-  Overflow _overflow;
-  set overflow(Overflow value) {
+  /// Defaults to [Clip.hardEdge], and must not be null.
+  Clip get clipBehavior => _clipBehavior;
+  Clip _clipBehavior = Clip.hardEdge;
+  set clipBehavior(Clip value) {
     assert(value != null);
-    if (_overflow != value) {
-      _overflow = value;
+    if (value != _clipBehavior) {
+      _clipBehavior = value;
       markNeedsPaint();
+      markNeedsSemanticsUpdate();
     }
   }
 
@@ -606,8 +608,8 @@ class RenderStack extends RenderBox
 
   @override
   void paint(PaintingContext context, Offset offset) {
-    if (_overflow == Overflow.clip && _hasVisualOverflow) {
-      context.pushClipRect(needsCompositing, offset, Offset.zero & size, paintStack);
+    if (clipBehavior != Clip.none && _hasVisualOverflow) {
+      context.pushClipRect(needsCompositing, offset, Offset.zero & size, paintStack, clipBehavior: clipBehavior);
     } else {
       paintStack(context, offset);
     }
@@ -622,7 +624,7 @@ class RenderStack extends RenderBox
     properties.add(DiagnosticsProperty<AlignmentGeometry>('alignment', alignment));
     properties.add(EnumProperty<TextDirection>('textDirection', textDirection));
     properties.add(EnumProperty<StackFit>('fit', fit));
-    properties.add(EnumProperty<Overflow>('overflow', overflow));
+    properties.add(EnumProperty<Clip>('clipBehavior', clipBehavior, defaultValue: Clip.hardEdge));
   }
 }
 

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

@@ -173,17 +173,20 @@ abstract class RenderViewportBase<ParentDataClass extends ContainerParentDataMix
     @required ViewportOffset offset,
     double cacheExtent,
     CacheExtentStyle cacheExtentStyle = CacheExtentStyle.pixel,
+    Clip clipBehavior = Clip.hardEdge,
   }) : assert(axisDirection != null),
        assert(crossAxisDirection != null),
        assert(offset != null),
        assert(axisDirectionToAxis(axisDirection) != axisDirectionToAxis(crossAxisDirection)),
        assert(cacheExtentStyle != null),
        assert(cacheExtent != null || cacheExtentStyle == CacheExtentStyle.pixel),
+       assert(clipBehavior != null),
        _axisDirection = axisDirection,
        _crossAxisDirection = crossAxisDirection,
        _offset = offset,
        _cacheExtent = cacheExtent ?? RenderAbstractViewport.defaultCacheExtent,
-       _cacheExtentStyle = cacheExtentStyle;
+       _cacheExtentStyle = cacheExtentStyle,
+       _clipBehavior = clipBehavior;
 
   @override
   void describeSemanticsConfiguration(SemanticsConfiguration config) {
@@ -316,6 +319,20 @@ abstract class RenderViewportBase<ParentDataClass extends ContainerParentDataMix
     markNeedsLayout();
   }
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge], and must not be null.
+  Clip get clipBehavior => _clipBehavior;
+  Clip _clipBehavior = Clip.hardEdge;
+  set clipBehavior(Clip value) {
+    assert(value != null);
+    if (value != _clipBehavior) {
+      _clipBehavior = value;
+      markNeedsPaint();
+      markNeedsSemanticsUpdate();
+    }
+  }
+
   @override
   void attach(PipelineOwner owner) {
     super.attach(owner);
@@ -576,8 +593,8 @@ abstract class RenderViewportBase<ParentDataClass extends ContainerParentDataMix
   void paint(PaintingContext context, Offset offset) {
     if (firstChild == null)
       return;
-    if (hasVisualOverflow) {
-      context.pushClipRect(needsCompositing, offset, Offset.zero & size, _paintContents);
+    if (hasVisualOverflow && clipBehavior != Clip.none) {
+      context.pushClipRect(needsCompositing, offset, Offset.zero & size, _paintContents, clipBehavior: clipBehavior);
     } else {
       _paintContents(context, offset);
     }
@@ -1138,9 +1155,11 @@ class RenderViewport extends RenderViewportBase<SliverPhysicalContainerParentDat
     RenderSliver center,
     double cacheExtent,
     CacheExtentStyle cacheExtentStyle = CacheExtentStyle.pixel,
+    Clip clipBehavior = Clip.hardEdge,
   }) : assert(anchor != null),
        assert(anchor >= 0.0 && anchor <= 1.0),
        assert(cacheExtentStyle != CacheExtentStyle.viewport || cacheExtent != null),
+       assert(clipBehavior != null),
        _anchor = anchor,
        _center = center,
        super(
@@ -1149,6 +1168,7 @@ class RenderViewport extends RenderViewportBase<SliverPhysicalContainerParentDat
          offset: offset,
          cacheExtent: cacheExtent,
          cacheExtentStyle: cacheExtentStyle,
+         clipBehavior: clipBehavior,
        ) {
     addAll(children);
     if (center == null && firstChild != null)
@@ -1660,8 +1680,14 @@ class RenderShrinkWrappingViewport extends RenderViewportBase<SliverLogicalConta
     AxisDirection axisDirection = AxisDirection.down,
     @required AxisDirection crossAxisDirection,
     @required ViewportOffset offset,
+    Clip clipBehavior = Clip.hardEdge,
     List<RenderSliver> children,
-  }) : super(axisDirection: axisDirection, crossAxisDirection: crossAxisDirection, offset: offset) {
+  }) : super(
+        axisDirection: axisDirection,
+        crossAxisDirection: crossAxisDirection,
+        offset: offset,
+        clipBehavior: clipBehavior,
+       ) {
     addAll(children);
   }
 

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

@@ -103,8 +103,9 @@ class WrapParentData extends ContainerBoxParentData<RenderBox> {
 ///
 /// The runs themselves are then positioned in the cross axis according to the
 /// [runSpacing] and [runAlignment].
-class RenderWrap extends RenderBox with ContainerRenderObjectMixin<RenderBox, WrapParentData>,
-                                        RenderBoxContainerDefaultsMixin<RenderBox, WrapParentData> {
+class RenderWrap extends RenderBox
+    with ContainerRenderObjectMixin<RenderBox, WrapParentData>,
+         RenderBoxContainerDefaultsMixin<RenderBox, WrapParentData> {
   /// Creates a wrap render object.
   ///
   /// By default, the wrap layout is horizontal and both the children and the
@@ -119,12 +120,14 @@ class RenderWrap extends RenderBox with ContainerRenderObjectMixin<RenderBox, Wr
     WrapCrossAlignment crossAxisAlignment = WrapCrossAlignment.start,
     TextDirection textDirection,
     VerticalDirection verticalDirection = VerticalDirection.down,
+    Clip clipBehavior = Clip.none,
   }) : assert(direction != null),
        assert(alignment != null),
        assert(spacing != null),
        assert(runAlignment != null),
        assert(runSpacing != null),
        assert(crossAxisAlignment != null),
+       assert(clipBehavior != null),
        _direction = direction,
        _alignment = alignment,
        _spacing = spacing,
@@ -132,7 +135,8 @@ class RenderWrap extends RenderBox with ContainerRenderObjectMixin<RenderBox, Wr
        _runSpacing = runSpacing,
        _crossAxisAlignment = crossAxisAlignment,
        _textDirection = textDirection,
-       _verticalDirection = verticalDirection {
+       _verticalDirection = verticalDirection,
+       _clipBehavior = clipBehavior {
     addAll(children);
   }
 
@@ -328,6 +332,20 @@ class RenderWrap extends RenderBox with ContainerRenderObjectMixin<RenderBox, Wr
     }
   }
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.none], and must not be null.
+  Clip get clipBehavior => _clipBehavior;
+  Clip _clipBehavior = Clip.none;
+  set clipBehavior(Clip value) {
+    assert(value != null);
+    if (value != _clipBehavior) {
+      _clipBehavior = value;
+      markNeedsPaint();
+      markNeedsSemanticsUpdate();
+    }
+  }
+
   bool get _debugHasNecessaryDirections {
     assert(direction != null);
     assert(alignment != null);
@@ -751,8 +769,8 @@ class RenderWrap extends RenderBox with ContainerRenderObjectMixin<RenderBox, Wr
   void paint(PaintingContext context, Offset offset) {
     // TODO(ianh): move the debug flex overflow paint logic somewhere common so
     // it can be reused here
-    if (_hasVisualOverflow)
-      context.pushClipRect(needsCompositing, offset, Offset.zero & size, defaultPaint);
+    if (_hasVisualOverflow && clipBehavior != Clip.none)
+      context.pushClipRect(needsCompositing, offset, Offset.zero & size, defaultPaint, clipBehavior: clipBehavior);
     else
       defaultPaint(context, offset);
   }

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

@@ -218,7 +218,7 @@ class AnimatedCrossFade extends StatefulWidget {
   /// [AnimatedCrossFadeBuilder].
   static Widget defaultLayoutBuilder(Widget topChild, Key topChildKey, Widget bottomChild, Key bottomChildKey) {
     return Stack(
-      overflow: Overflow.visible,
+      clipBehavior: Clip.none,
       children: <Widget>[
         Positioned(
           key: bottomChildKey,

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

@@ -43,8 +43,8 @@ export 'package:flutter/rendering.dart' show
   LayerLink,
   MainAxisAlignment,
   MainAxisSize,
-  MultiChildLayoutDelegate,
   Overflow,
+  MultiChildLayoutDelegate,
   PaintingContext,
   PointerCancelEvent,
   PointerCancelEventListener,
@@ -1413,9 +1413,11 @@ class FittedBox extends SingleChildRenderObjectWidget {
     Key key,
     this.fit = BoxFit.contain,
     this.alignment = Alignment.center,
+    this.clipBehavior = Clip.hardEdge,
     Widget child,
   }) : assert(fit != null),
        assert(alignment != null),
+       assert(clipBehavior != null),
        super(key: key, child: child);
 
   /// How to inscribe the child into the space allocated during layout.
@@ -1437,12 +1439,19 @@ class FittedBox extends SingleChildRenderObjectWidget {
   ///    relative to text direction.
   final AlignmentGeometry alignment;
 
+  // TODO(liyuqian): defaults to [Clip.none] once Google references are updated.
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   @override
   RenderFittedBox createRenderObject(BuildContext context) {
     return RenderFittedBox(
       fit: fit,
       alignment: alignment,
       textDirection: Directionality.of(context),
+      clipBehavior: clipBehavior,
     );
   }
 
@@ -1451,7 +1460,8 @@ class FittedBox extends SingleChildRenderObjectWidget {
     renderObject
       ..fit = fit
       ..alignment = alignment
-      ..textDirection = Directionality.of(context);
+      ..textDirection = Directionality.of(context)
+      ..clipBehavior = clipBehavior;
   }
 
   @override
@@ -2233,7 +2243,9 @@ class UnconstrainedBox extends SingleChildRenderObjectWidget {
     this.textDirection,
     this.alignment = Alignment.center,
     this.constrainedAxis,
+    this.clipBehavior = Clip.hardEdge,
   }) : assert(alignment != null),
+       assert(clipBehavior != null),
        super(key: key, child: child);
 
   /// The text direction to use when interpreting the [alignment] if it is an
@@ -2259,12 +2271,19 @@ class UnconstrainedBox extends SingleChildRenderObjectWidget {
   /// will be retained.
   final Axis constrainedAxis;
 
+  // TODO(liyuqian): defaults to [Clip.none] once Google references are updated.
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   @override
   void updateRenderObject(BuildContext context, covariant RenderUnconstrainedBox renderObject) {
     renderObject
       ..textDirection = textDirection ?? Directionality.of(context)
       ..alignment = alignment
-      ..constrainedAxis = constrainedAxis;
+      ..constrainedAxis = constrainedAxis
+      ..clipBehavior = clipBehavior;
   }
 
   @override
@@ -2272,6 +2291,7 @@ class UnconstrainedBox extends SingleChildRenderObjectWidget {
     textDirection: textDirection ?? Directionality.of(context),
     alignment: alignment,
     constrainedAxis: constrainedAxis,
+    clipBehavior: clipBehavior,
   );
 
   @override
@@ -3218,8 +3238,10 @@ class Stack extends MultiChildRenderObjectWidget {
     this.textDirection,
     this.fit = StackFit.loose,
     this.overflow = Overflow.clip,
+    this.clipBehavior = Clip.hardEdge,
     List<Widget> children = const <Widget>[],
-  }) : super(key: key, children: children);
+  }) : assert(clipBehavior != null),
+       super(key: key, children: children);
 
   /// How to align the non-positioned and partially-positioned children in the
   /// stack.
@@ -3256,12 +3278,22 @@ class Stack extends MultiChildRenderObjectWidget {
   /// ([StackFit.expand]).
   final StackFit fit;
 
+  // TODO(liyuqian): Deprecate and remove [overflow] once its usages are removed from Google.
+
   /// Whether overflowing children should be clipped. See [Overflow].
   ///
   /// Some children in a stack might overflow its box. When this flag is set to
   /// [Overflow.clip], children cannot paint outside of the stack's box.
+  ///
+  /// This overrides [clipBehavior] for now due to a staged roll out without
+  /// breaking Google. We will remove it and only use [clipBehavior] soon.
   final Overflow overflow;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   bool _debugCheckHasDirectionality(BuildContext context) {
     if (alignment is AlignmentDirectional && textDirection == null) {
       assert(debugCheckHasDirectionality(
@@ -3281,7 +3313,7 @@ class Stack extends MultiChildRenderObjectWidget {
       alignment: alignment,
       textDirection: textDirection ?? Directionality.of(context),
       fit: fit,
-      overflow: overflow,
+      clipBehavior: overflow == Overflow.visible ? Clip.none : clipBehavior,
     );
   }
 
@@ -3292,7 +3324,7 @@ class Stack extends MultiChildRenderObjectWidget {
       ..alignment = alignment
       ..textDirection = textDirection ?? Directionality.of(context)
       ..fit = fit
-      ..overflow = overflow;
+      ..clipBehavior = overflow == Overflow.visible ? Clip.none : clipBehavior;
   }
 
   @override
@@ -3301,7 +3333,7 @@ class Stack extends MultiChildRenderObjectWidget {
     properties.add(DiagnosticsProperty<AlignmentGeometry>('alignment', alignment));
     properties.add(EnumProperty<TextDirection>('textDirection', textDirection, defaultValue: null));
     properties.add(EnumProperty<StackFit>('fit', fit));
-    properties.add(EnumProperty<Overflow>('overflow', overflow));
+    properties.add(EnumProperty<Clip>('clipBehavior', clipBehavior, defaultValue: Clip.hardEdge));
   }
 }
 
@@ -3829,6 +3861,7 @@ class Flex extends MultiChildRenderObjectWidget {
     this.textDirection,
     this.verticalDirection = VerticalDirection.down,
     this.textBaseline,
+    this.clipBehavior = Clip.hardEdge,
     List<Widget> children = const <Widget>[],
   }) : assert(direction != null),
        assert(mainAxisAlignment != null),
@@ -3836,6 +3869,7 @@ class Flex extends MultiChildRenderObjectWidget {
        assert(crossAxisAlignment != null),
        assert(verticalDirection != null),
        assert(crossAxisAlignment != CrossAxisAlignment.baseline || textBaseline != null),
+       assert(clipBehavior != null),
        super(key: key, children: children);
 
   /// The direction to use as the main axis.
@@ -3920,6 +3954,12 @@ class Flex extends MultiChildRenderObjectWidget {
   /// If aligning items according to their baseline, which baseline to use.
   final TextBaseline textBaseline;
 
+  // TODO(liyuqian): defaults to [Clip.none] once Google references are updated.
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   bool get _needTextDirection {
     assert(direction != null);
     switch (direction) {
@@ -3963,6 +4003,7 @@ class Flex extends MultiChildRenderObjectWidget {
       textDirection: getEffectiveTextDirection(context),
       verticalDirection: verticalDirection,
       textBaseline: textBaseline,
+      clipBehavior: clipBehavior,
     );
   }
 
@@ -3975,7 +4016,8 @@ class Flex extends MultiChildRenderObjectWidget {
       ..crossAxisAlignment = crossAxisAlignment
       ..textDirection = getEffectiveTextDirection(context)
       ..verticalDirection = verticalDirection
-      ..textBaseline = textBaseline;
+      ..textBaseline = textBaseline
+      ..clipBehavior = clipBehavior;
   }
 
   @override
@@ -4646,8 +4688,9 @@ class Wrap extends MultiChildRenderObjectWidget {
     this.crossAxisAlignment = WrapCrossAlignment.start,
     this.textDirection,
     this.verticalDirection = VerticalDirection.down,
+    this.clipBehavior = Clip.hardEdge,
     List<Widget> children = const <Widget>[],
-  }) : super(key: key, children: children);
+  }) : assert(clipBehavior != null), super(key: key, children: children);
 
   /// The direction to use as the main axis.
   ///
@@ -4781,6 +4824,12 @@ class Wrap extends MultiChildRenderObjectWidget {
   /// [verticalDirection] must not be null.
   final VerticalDirection verticalDirection;
 
+  // TODO(liyuqian): defaults to [Clip.none] once Google references are updated.
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   @override
   RenderWrap createRenderObject(BuildContext context) {
     return RenderWrap(
@@ -4792,6 +4841,7 @@ class Wrap extends MultiChildRenderObjectWidget {
       crossAxisAlignment: crossAxisAlignment,
       textDirection: textDirection ?? Directionality.of(context),
       verticalDirection: verticalDirection,
+      clipBehavior: clipBehavior,
     );
   }
 
@@ -4805,7 +4855,8 @@ class Wrap extends MultiChildRenderObjectWidget {
       ..runSpacing = runSpacing
       ..crossAxisAlignment = crossAxisAlignment
       ..textDirection = textDirection ?? Directionality.of(context)
-      ..verticalDirection = verticalDirection;
+      ..verticalDirection = verticalDirection
+      ..clipBehavior = clipBehavior;
   }
 
   @override

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

@@ -417,6 +417,7 @@ class EditableText extends StatefulWidget {
       selectAll: true,
     ),
     this.autofillHints,
+    this.clipBehavior = Clip.hardEdge,
   }) : assert(controller != null),
        assert(focusNode != null),
        assert(obscuringCharacter != null && obscuringCharacter.length == 1),
@@ -454,6 +455,7 @@ class EditableText extends StatefulWidget {
        assert(scrollPadding != null),
        assert(dragStartBehavior != null),
        assert(toolbarOptions != null),
+       assert(clipBehavior != null),
        _strutStyle = strutStyle,
        keyboardType = keyboardType ?? _inferKeyboardType(autofillHints: autofillHints, maxLines: maxLines),
        inputFormatters = maxLines == 1
@@ -1139,6 +1141,11 @@ class EditableText extends StatefulWidget {
   /// {@macro flutter.services.autofill.autofillHints}
   final Iterable<String> autofillHints;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   // Infer the keyboard type of an `EditableText` if it's not specified.
   static TextInputType _inferKeyboardType({
     @required Iterable<String> autofillHints,
@@ -2268,6 +2275,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
                 devicePixelRatio: _devicePixelRatio,
                 promptRectRange: _currentPromptRectRange,
                 promptRectColor: widget.autocorrectionTextRectColor,
+                clipBehavior: widget.clipBehavior,
               ),
             ),
           );
@@ -2349,6 +2357,7 @@ class _Editable extends LeafRenderObjectWidget {
     this.devicePixelRatio,
     this.promptRectRange,
     this.promptRectColor,
+    this.clipBehavior,
   }) : assert(textDirection != null),
        assert(rendererIgnoresPointer != null),
        super(key: key);
@@ -2395,6 +2404,7 @@ class _Editable extends LeafRenderObjectWidget {
   final double devicePixelRatio;
   final TextRange promptRectRange;
   final Color promptRectColor;
+  final Clip clipBehavior;
 
   @override
   RenderEditable createRenderObject(BuildContext context) {
@@ -2437,6 +2447,7 @@ class _Editable extends LeafRenderObjectWidget {
       devicePixelRatio: devicePixelRatio,
       promptRectRange: promptRectRange,
       promptRectColor: promptRectColor,
+      clipBehavior: clipBehavior,
     );
   }
 
@@ -2478,6 +2489,7 @@ class _Editable extends LeafRenderObjectWidget {
       ..devicePixelRatio = devicePixelRatio
       ..paintCursorAboveText = paintCursorAboveText
       ..promptRectColor = promptRectColor
+      ..clipBehavior = clipBehavior
       ..setPromptRectRange(promptRectRange);
   }
 }

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

@@ -581,8 +581,8 @@ class ListWheelScrollView extends StatefulWidget {
     @required this.itemExtent,
     this.squeeze = 1.0,
     this.onSelectedItemChanged,
-    this.clipToSize = true,
     this.renderChildrenOutsideViewport = false,
+    this.clipBehavior = Clip.hardEdge,
     @required List<Widget> children,
   }) : assert(children != null),
        assert(diameterRatio != null),
@@ -597,11 +597,11 @@ class ListWheelScrollView extends StatefulWidget {
        assert(itemExtent > 0),
        assert(squeeze != null),
        assert(squeeze > 0),
-       assert(clipToSize != null),
        assert(renderChildrenOutsideViewport != null),
+       assert(clipBehavior != null),
        assert(
-         !renderChildrenOutsideViewport || !clipToSize,
-         RenderListWheelViewport.clipToSizeAndRenderChildrenOutsideViewportConflict,
+         !renderChildrenOutsideViewport || clipBehavior == Clip.none,
+         RenderListWheelViewport.clipBehaviorAndRenderChildrenOutsideViewportConflict,
        ),
        childDelegate = ListWheelChildListDelegate(children: children),
        super(key: key);
@@ -621,8 +621,8 @@ class ListWheelScrollView extends StatefulWidget {
     @required this.itemExtent,
     this.squeeze = 1.0,
     this.onSelectedItemChanged,
-    this.clipToSize = true,
     this.renderChildrenOutsideViewport = false,
+    this.clipBehavior = Clip.hardEdge,
     @required this.childDelegate,
   }) : assert(childDelegate != null),
        assert(diameterRatio != null),
@@ -637,11 +637,11 @@ class ListWheelScrollView extends StatefulWidget {
        assert(itemExtent > 0),
        assert(squeeze != null),
        assert(squeeze > 0),
-       assert(clipToSize != null),
        assert(renderChildrenOutsideViewport != null),
+       assert(clipBehavior != null),
        assert(
-         !renderChildrenOutsideViewport || !clipToSize,
-         RenderListWheelViewport.clipToSizeAndRenderChildrenOutsideViewportConflict,
+         !renderChildrenOutsideViewport || clipBehavior == Clip.none,
+         RenderListWheelViewport.clipBehaviorAndRenderChildrenOutsideViewportConflict,
        ),
        super(key: key);
 
@@ -700,15 +700,17 @@ class ListWheelScrollView extends StatefulWidget {
   /// On optional listener that's called when the centered item changes.
   final ValueChanged<int> onSelectedItemChanged;
 
-  /// {@macro flutter.rendering.wheelList.clipToSize}
-  final bool clipToSize;
-
   /// {@macro flutter.rendering.wheelList.renderChildrenOutsideViewport}
   final bool renderChildrenOutsideViewport;
 
   /// A delegate that helps lazily instantiating child.
   final ListWheelChildDelegate childDelegate;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   @override
   _ListWheelScrollViewState createState() => _ListWheelScrollViewState();
 }
@@ -771,10 +773,10 @@ class _ListWheelScrollViewState extends State<ListWheelScrollView> {
             overAndUnderCenterOpacity: widget.overAndUnderCenterOpacity,
             itemExtent: widget.itemExtent,
             squeeze: widget.squeeze,
-            clipToSize: widget.clipToSize,
             renderChildrenOutsideViewport: widget.renderChildrenOutsideViewport,
             offset: offset,
             childDelegate: widget.childDelegate,
+            clipBehavior: widget.clipBehavior,
           );
         },
       ),
@@ -952,7 +954,7 @@ class ListWheelViewport extends RenderObjectWidget {
   ///
   /// The [itemExtent] argument in pixels must be provided and must be positive.
   ///
-  /// The [clipToSize] argument defaults to true and must not be null.
+  /// The [clipBehavior] argument defaults to [Clip.hardEdge] and must not be null.
   ///
   /// The [renderChildrenOutsideViewport] argument defaults to false and must
   /// not be null.
@@ -968,10 +970,10 @@ class ListWheelViewport extends RenderObjectWidget {
     this.overAndUnderCenterOpacity = 1.0,
     @required this.itemExtent,
     this.squeeze = 1.0,
-    this.clipToSize = true,
     this.renderChildrenOutsideViewport = false,
     @required this.offset,
     @required this.childDelegate,
+    this.clipBehavior = Clip.hardEdge,
   }) : assert(childDelegate != null),
        assert(offset != null),
        assert(diameterRatio != null),
@@ -985,11 +987,11 @@ class ListWheelViewport extends RenderObjectWidget {
        assert(itemExtent > 0),
        assert(squeeze != null),
        assert(squeeze > 0),
-       assert(clipToSize != null),
        assert(renderChildrenOutsideViewport != null),
+       assert(clipBehavior != null),
        assert(
-         !renderChildrenOutsideViewport || !clipToSize,
-         RenderListWheelViewport.clipToSizeAndRenderChildrenOutsideViewportConflict,
+         !renderChildrenOutsideViewport || clipBehavior == Clip.none,
+         RenderListWheelViewport.clipBehaviorAndRenderChildrenOutsideViewportConflict,
        ),
        super(key: key);
 
@@ -1019,9 +1021,6 @@ class ListWheelViewport extends RenderObjectWidget {
   /// Defaults to 1.
   final double squeeze;
 
-  /// {@macro flutter.rendering.wheelList.clipToSize}
-  final bool clipToSize;
-
   /// {@macro flutter.rendering.wheelList.renderChildrenOutsideViewport}
   final bool renderChildrenOutsideViewport;
 
@@ -1032,6 +1031,11 @@ class ListWheelViewport extends RenderObjectWidget {
   /// A delegate that lazily instantiates children.
   final ListWheelChildDelegate childDelegate;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.none].
+  final Clip clipBehavior;
+
   @override
   ListWheelElement createElement() => ListWheelElement(this);
 
@@ -1049,8 +1053,8 @@ class ListWheelViewport extends RenderObjectWidget {
       overAndUnderCenterOpacity: overAndUnderCenterOpacity,
       itemExtent: itemExtent,
       squeeze: squeeze,
-      clipToSize: clipToSize,
       renderChildrenOutsideViewport: renderChildrenOutsideViewport,
+      clipBehavior: clipBehavior,
     );
   }
 
@@ -1066,7 +1070,7 @@ class ListWheelViewport extends RenderObjectWidget {
       ..overAndUnderCenterOpacity = overAndUnderCenterOpacity
       ..itemExtent = itemExtent
       ..squeeze = squeeze
-      ..clipToSize = clipToSize
-      ..renderChildrenOutsideViewport = renderChildrenOutsideViewport;
+      ..renderChildrenOutsideViewport = renderChildrenOutsideViewport
+      ..clipBehavior = clipBehavior;
   }
 }

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

@@ -375,11 +375,13 @@ class NestedScrollView extends StatefulWidget {
     @required this.body,
     this.dragStartBehavior = DragStartBehavior.start,
     this.floatHeaderSlivers = false,
+    this.clipBehavior = Clip.hardEdge,
   }) : assert(scrollDirection != null),
        assert(reverse != null),
        assert(headerSliverBuilder != null),
        assert(body != null),
        assert(floatHeaderSlivers != null),
+       assert(clipBehavior != null),
        super(key: key);
 
   /// An object that can be used to control the position to which the outer
@@ -450,6 +452,11 @@ class NestedScrollView extends StatefulWidget {
   /// is expected to float. This cannot be null.
   final bool floatHeaderSlivers;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   /// Returns the [SliverOverlapAbsorberHandle] of the nearest ancestor
   /// [NestedScrollView].
   ///
@@ -628,6 +635,7 @@ class NestedScrollViewState extends State<NestedScrollView> {
               _lastHasScrolledBody,
             ),
             handle: _absorberHandle,
+            clipBehavior: widget.clipBehavior,
           );
         },
       ),
@@ -643,6 +651,7 @@ class _NestedScrollViewCustomScrollView extends CustomScrollView {
     @required ScrollController controller,
     @required List<Widget> slivers,
     @required this.handle,
+    @required this.clipBehavior,
     DragStartBehavior dragStartBehavior = DragStartBehavior.start,
   }) : super(
          scrollDirection: scrollDirection,
@@ -654,6 +663,7 @@ class _NestedScrollViewCustomScrollView extends CustomScrollView {
        );
 
   final SliverOverlapAbsorberHandle handle;
+  final Clip clipBehavior;
 
   @override
   Widget buildViewport(
@@ -668,6 +678,7 @@ class _NestedScrollViewCustomScrollView extends CustomScrollView {
       offset: offset,
       slivers: slivers,
       handle: handle,
+      clipBehavior: clipBehavior,
     );
   }
 }
@@ -2034,6 +2045,7 @@ class NestedScrollViewViewport extends Viewport {
     Key center,
     List<Widget> slivers = const <Widget>[],
     @required this.handle,
+    Clip clipBehavior = Clip.hardEdge,
   }) : assert(handle != null),
        super(
          key: key,
@@ -2043,6 +2055,7 @@ class NestedScrollViewViewport extends Viewport {
          offset: offset,
          center: center,
          slivers: slivers,
+         clipBehavior: clipBehavior,
        );
 
   /// The handle to the [SliverOverlapAbsorber] that is feeding this injector.
@@ -2059,6 +2072,7 @@ class NestedScrollViewViewport extends Viewport {
       anchor: anchor,
       offset: offset,
       handle: handle,
+      clipBehavior: clipBehavior,
     );
   }
 
@@ -2072,7 +2086,8 @@ class NestedScrollViewViewport extends Viewport {
       )
       ..anchor = anchor
       ..offset = offset
-      ..handle = handle;
+      ..handle = handle
+      ..clipBehavior = clipBehavior;
   }
 
   @override
@@ -2099,6 +2114,7 @@ class RenderNestedScrollViewViewport extends RenderViewport {
     List<RenderSliver> children,
     RenderSliver center,
     @required SliverOverlapAbsorberHandle handle,
+    Clip clipBehavior = Clip.hardEdge,
   }) : assert(handle != null),
        _handle = handle,
        super(
@@ -2108,6 +2124,7 @@ class RenderNestedScrollViewViewport extends RenderViewport {
          anchor: anchor,
          children: children,
          center: center,
+         clipBehavior: clipBehavior,
        );
 
   /// The object to notify when [markNeedsLayout] is called.

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

@@ -221,8 +221,10 @@ class SingleChildScrollView extends StatelessWidget {
     this.controller,
     this.child,
     this.dragStartBehavior = DragStartBehavior.start,
+    this.clipBehavior = Clip.hardEdge,
   }) : assert(scrollDirection != null),
        assert(dragStartBehavior != null),
+       assert(clipBehavior != null),
        assert(!(controller != null && primary == true),
           'Primary ScrollViews obtain their ScrollController via inheritance from a PrimaryScrollController widget. '
           'You cannot both set primary to true and pass an explicit controller.'
@@ -292,6 +294,11 @@ class SingleChildScrollView extends StatelessWidget {
   /// {@macro flutter.widgets.scrollable.dragStartBehavior}
   final DragStartBehavior dragStartBehavior;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   AxisDirection _getDirection(BuildContext context) {
     return getAxisDirectionFromAxisReverseAndDirectionality(context, scrollDirection, reverse);
   }
@@ -315,6 +322,7 @@ class SingleChildScrollView extends StatelessWidget {
           axisDirection: axisDirection,
           offset: offset,
           child: contents,
+          clipBehavior: clipBehavior,
         );
       },
     );
@@ -330,17 +338,21 @@ class _SingleChildViewport extends SingleChildRenderObjectWidget {
     this.axisDirection = AxisDirection.down,
     this.offset,
     Widget child,
+    @required this.clipBehavior,
   }) : assert(axisDirection != null),
+       assert(clipBehavior != null),
        super(key: key, child: child);
 
   final AxisDirection axisDirection;
   final ViewportOffset offset;
+  final Clip clipBehavior;
 
   @override
   _RenderSingleChildViewport createRenderObject(BuildContext context) {
     return _RenderSingleChildViewport(
       axisDirection: axisDirection,
       offset: offset,
+      clipBehavior: clipBehavior,
     );
   }
 
@@ -349,7 +361,8 @@ class _SingleChildViewport extends SingleChildRenderObjectWidget {
     // Order dependency: The offset setter reads the axis direction.
     renderObject
       ..axisDirection = axisDirection
-      ..offset = offset;
+      ..offset = offset
+      ..clipBehavior = clipBehavior;
   }
 }
 
@@ -359,12 +372,15 @@ class _RenderSingleChildViewport extends RenderBox with RenderObjectWithChildMix
     @required ViewportOffset offset,
     double cacheExtent = RenderAbstractViewport.defaultCacheExtent,
     RenderBox child,
+    @required Clip clipBehavior,
   }) : assert(axisDirection != null),
        assert(offset != null),
        assert(cacheExtent != null),
+       assert(clipBehavior != null),
        _axisDirection = axisDirection,
        _offset = offset,
-       _cacheExtent = cacheExtent {
+       _cacheExtent = cacheExtent,
+       _clipBehavior = clipBehavior {
     this.child = child;
   }
 
@@ -405,6 +421,20 @@ class _RenderSingleChildViewport extends RenderBox with RenderObjectWithChildMix
     markNeedsLayout();
   }
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.none], and must not be null.
+  Clip get clipBehavior => _clipBehavior;
+  Clip _clipBehavior = Clip.none;
+  set clipBehavior(Clip value) {
+    assert(value != null);
+    if (value != _clipBehavior) {
+      _clipBehavior = value;
+      markNeedsPaint();
+      markNeedsSemanticsUpdate();
+    }
+  }
+
   void _hasScrolled() {
     markNeedsPaint();
     markNeedsSemanticsUpdate();
@@ -550,8 +580,8 @@ class _RenderSingleChildViewport extends RenderBox with RenderObjectWithChildMix
         context.paintChild(child, offset + paintOffset);
       }
 
-      if (_shouldClipAtPaintOffset(paintOffset)) {
-        context.pushClipRect(needsCompositing, offset, Offset.zero & size, paintContents);
+      if (_shouldClipAtPaintOffset(paintOffset) && clipBehavior != Clip.none) {
+        context.pushClipRect(needsCompositing, offset, Offset.zero & size, paintContents, clipBehavior: clipBehavior);
       } else {
         paintContents(context, offset);
       }

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

@@ -60,12 +60,14 @@ class Viewport extends MultiChildRenderObjectWidget {
     this.center,
     this.cacheExtent,
     this.cacheExtentStyle = CacheExtentStyle.pixel,
+    this.clipBehavior = Clip.hardEdge,
     List<Widget> slivers = const <Widget>[],
   }) : assert(offset != null),
        assert(slivers != null),
        assert(center == null || slivers.where((Widget child) => child.key == center).length == 1),
        assert(cacheExtentStyle != null),
        assert(cacheExtentStyle != CacheExtentStyle.viewport || cacheExtent != null),
+       assert(clipBehavior != null),
        super(key: key, children: slivers);
 
   /// The direction in which the [offset]'s [ViewportOffset.pixels] increases.
@@ -120,6 +122,11 @@ class Viewport extends MultiChildRenderObjectWidget {
   /// {@macro flutter.rendering.viewport.cacheExtentStyle}
   final CacheExtentStyle cacheExtentStyle;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.none].
+  final Clip clipBehavior;
+
   /// Given a [BuildContext] and an [AxisDirection], determine the correct cross
   /// axis direction.
   ///
@@ -149,6 +156,7 @@ class Viewport extends MultiChildRenderObjectWidget {
       offset: offset,
       cacheExtent: cacheExtent,
       cacheExtentStyle: cacheExtentStyle,
+      clipBehavior: clipBehavior,
     );
   }
 
@@ -160,7 +168,8 @@ class Viewport extends MultiChildRenderObjectWidget {
       ..anchor = anchor
       ..offset = offset
       ..cacheExtent = cacheExtent
-      ..cacheExtentStyle = cacheExtentStyle;
+      ..cacheExtentStyle = cacheExtentStyle
+      ..clipBehavior = clipBehavior;
   }
 
   @override
@@ -265,6 +274,7 @@ class ShrinkWrappingViewport extends MultiChildRenderObjectWidget {
     this.axisDirection = AxisDirection.down,
     this.crossAxisDirection,
     @required this.offset,
+    this.clipBehavior = Clip.hardEdge,
     List<Widget> slivers = const <Widget>[],
   }) : assert(offset != null),
        super(key: key, children: slivers);
@@ -297,12 +307,18 @@ class ShrinkWrappingViewport extends MultiChildRenderObjectWidget {
   /// Typically a [ScrollPosition].
   final ViewportOffset offset;
 
+  /// {@macro flutter.widgets.Clip}
+  ///
+  /// Defaults to [Clip.hardEdge].
+  final Clip clipBehavior;
+
   @override
   RenderShrinkWrappingViewport createRenderObject(BuildContext context) {
     return RenderShrinkWrappingViewport(
       axisDirection: axisDirection,
       crossAxisDirection: crossAxisDirection ?? Viewport.getDefaultCrossAxisDirection(context, axisDirection),
       offset: offset,
+      clipBehavior: clipBehavior,
     );
   }
 
@@ -311,7 +327,8 @@ class ShrinkWrappingViewport extends MultiChildRenderObjectWidget {
     renderObject
       ..axisDirection = axisDirection
       ..crossAxisDirection = crossAxisDirection ?? Viewport.getDefaultCrossAxisDirection(context, axisDirection)
-      ..offset = offset;
+      ..offset = offset
+      ..clipBehavior = clipBehavior;
   }
 
   @override

packages/flutter/test/material/dropdown_test.dart

@@ -2145,8 +2145,8 @@ void main() {
                           // hard coded 16px margin in the dropdown code, so that
                           // this hint aligns "properly" with the menu.
                           return Stack(
+                            clipBehavior: Clip.none,
                             alignment: Alignment.topCenter,
-                            overflow: Overflow.visible,
                             children: <Widget>[
                               PositionedDirectional(
                                 width: constraints.maxWidth + hintPaddingOffset,

packages/flutter/test/rendering/box_test.dart

@@ -672,6 +672,33 @@ void main() {
     expect(unconstrained.size.height, equals(100.0), reason: 'constrained height');
   });
 
+  test('clipBehavior is respected', () {
+    const BoxConstraints viewport = BoxConstraints(maxHeight: 100.0, maxWidth: 100.0);
+    final TestClipPaintingContext context = TestClipPaintingContext();
+
+    // By default, clipBehavior should be Clip.none
+    final RenderUnconstrainedBox defaultBox = RenderUnconstrainedBox(
+      alignment: Alignment.center,
+      textDirection: TextDirection.ltr,
+      child: box200x200,
+    );
+    layout(defaultBox, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+    defaultBox.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.none));
+
+    for (final Clip clip in Clip.values) {
+      final RenderUnconstrainedBox box = RenderUnconstrainedBox(
+          alignment: Alignment.center,
+          textDirection: TextDirection.ltr,
+          child: box200x200,
+          clipBehavior: clip,
+      );
+      layout(box, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+      box.paint(context, Offset.zero);
+      expect(context.clipBehavior, equals(clip));
+    }
+  });
+
   group('hit testing', () {
     test('BoxHitTestResult wrapping HitTestResult', () {
       final HitTestEntry entry1 = HitTestEntry(_DummyHitTestTarget());

packages/flutter/test/rendering/editable_test.dart

@@ -26,6 +26,44 @@ class FakeEditableTextState with TextSelectionDelegate {
 }
 
 void main() {
+  test('RenderEditable respects clipBehavior', () {
+    const BoxConstraints viewport = BoxConstraints(maxHeight: 100.0, maxWidth: 100.0);
+    final TestClipPaintingContext context = TestClipPaintingContext();
+
+    final String longString = 'a' * 10000;
+
+    // By default, clipBehavior should be Clip.none
+    final RenderEditable defaultEditable = RenderEditable(
+      text: TextSpan(text: longString),
+      textDirection: TextDirection.ltr,
+      startHandleLayerLink: LayerLink(),
+      endHandleLayerLink: LayerLink(),
+      offset: ViewportOffset.zero(),
+      textSelectionDelegate: FakeEditableTextState(),
+      selection: const TextSelection(baseOffset: 0, extentOffset: 0),
+    );
+    layout(defaultEditable, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+    defaultEditable.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.hardEdge));
+
+    context.clipBehavior = Clip.none; // Reset as Clip.none won't write into clipBehavior.
+    for (final Clip clip in Clip.values) {
+      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,
+      );
+      layout(editable, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+      editable.paint(context, Offset.zero);
+      expect(context.clipBehavior, equals(clip));
+    }
+  });
+
   test('editable intrinsics', () {
     final TextSelectionDelegate delegate = FakeEditableTextState();
     final RenderEditable editable = RenderEditable(

packages/flutter/test/rendering/flex_test.dart

@@ -54,6 +54,24 @@ void main() {
     FlutterError.onError = oldHandler;
   });
 
+  test('Clip behavior is respected', () {
+    const BoxConstraints viewport = BoxConstraints(maxHeight: 100.0, maxWidth: 100.0);
+    final TestClipPaintingContext context = TestClipPaintingContext();
+
+    // By default, clipBehavior should be Clip.none
+    final RenderFlex defaultFlex = RenderFlex(direction: Axis.vertical, children: <RenderBox>[box200x200]);
+    layout(defaultFlex, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+    defaultFlex.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.none));
+
+    for (final Clip clip in Clip.values) {
+      final RenderFlex flex = RenderFlex(direction: Axis.vertical, children: <RenderBox>[box200x200], clipBehavior: clip);
+      layout(flex, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+      flex.paint(context, Offset.zero);
+      expect(context.clipBehavior, equals(clip));
+    }
+  });
+
   test('Vertical Overflow', () {
     final RenderConstrainedBox flexible = RenderConstrainedBox(
       additionalConstraints: const BoxConstraints.expand()

packages/flutter/test/rendering/proxy_box_test.dart

@@ -433,6 +433,7 @@ void main() {
     _testLayerReuse<ClipRectLayer>(RenderFittedBox(
       alignment: Alignment.center,
       fit: BoxFit.cover,
+      clipBehavior: Clip.hardEdge,
       // Inject opacity under the clip to force compositing.
       child: RenderOpacity(
         opacity: 0.5,
@@ -470,6 +471,24 @@ void main() {
     _testFittedBoxWithClipRectLayer();
   });
 
+  test('RenderFittedBox respects clipBehavior', () {
+    const BoxConstraints viewport = BoxConstraints(maxHeight: 100.0, maxWidth: 100.0);
+    final TestClipPaintingContext context = TestClipPaintingContext();
+
+    // By default, clipBehavior should be Clip.none
+    final RenderFittedBox defaultBox = RenderFittedBox(child: box200x200, fit: BoxFit.none);
+    layout(defaultBox, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+    defaultBox.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.none));
+
+    for (final Clip clip in Clip.values) {
+      final RenderFittedBox box = RenderFittedBox(child: box200x200, fit: BoxFit.none, clipBehavior: clip);
+      layout(box, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+      box.paint(context, Offset.zero);
+      expect(context.clipBehavior, equals(clip));
+    }
+  });
+
   test('RenderMouseRegion can change properties when detached', () {
     renderer.initMouseTracker(MouseTracker(
       renderer.pointerRouter,

packages/flutter/test/rendering/rendering_tester.dart

@@ -296,3 +296,26 @@ class FakeTicker implements Ticker {
     return DiagnosticsProperty<Ticker>(name, this, style: DiagnosticsTreeStyle.errorProperty);
   }
 }
+
+class TestClipPaintingContext extends PaintingContext {
+  TestClipPaintingContext() : super(ContainerLayer(), Rect.zero);
+
+  @override
+  ClipRectLayer pushClipRect(bool needsCompositing, Offset offset, Rect clipRect, PaintingContextCallback painter, {Clip clipBehavior = Clip.hardEdge, ClipRectLayer oldLayer}) {
+    this.clipBehavior = clipBehavior;
+    return null;
+  }
+
+  Clip clipBehavior = Clip.none;
+}
+
+void expectOverflowedErrors() {
+  final FlutterErrorDetails errorDetails = renderer.takeFlutterErrorDetails();
+  final bool overflowed = errorDetails.toString().contains('overflowed');
+  if (!overflowed) {
+    FlutterError.reportError(errorDetails);
+  }
+}
+
+RenderConstrainedBox get box200x200 =>
+    RenderConstrainedBox(additionalConstraints: const BoxConstraints.tightFor(height: 200.0, width: 200.0));

packages/flutter/test/rendering/stack_test.dart

@@ -63,6 +63,33 @@ void main() {
     expect(stack.size.height, equals(100.0));
   });
 
+  test('Stack respects clipBehavior', () {
+    const BoxConstraints viewport = BoxConstraints(maxHeight: 100.0, maxWidth: 100.0);
+    final TestClipPaintingContext context = TestClipPaintingContext();
+
+    // By default, clipBehavior should be Clip.none
+    final RenderStack defaultStack = RenderStack(textDirection: TextDirection.ltr, children: <RenderBox>[box200x200]);
+    layout(defaultStack, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+    defaultStack.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.none));
+
+    for (final Clip clip in Clip.values) {
+      final RenderBox child = box200x200;
+      final RenderStack stack = RenderStack(
+          textDirection: TextDirection.ltr,
+          children: <RenderBox>[child],
+          clipBehavior: clip,
+      );
+      { // Make sure that the child is positioned so the stack will consider it as overflowed.
+        final StackParentData parentData = child.parentData as StackParentData;
+        parentData.left = parentData.right = 0;
+      }
+      layout(stack, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+      stack.paint(context, Offset.zero);
+      expect(context.clipBehavior, equals(clip));
+    }
+  });
+
   group('RenderIndexedStack', () {
     test('visitChildrenForSemantics only visits displayed child', () {
       final RenderBox child1 = RenderConstrainedBox(

packages/flutter/test/rendering/wrap_test.dart

@@ -7,6 +7,8 @@
 import 'package:flutter/rendering.dart';
 import 'package:flutter_test/flutter_test.dart';
 
+import 'rendering_tester.dart';
+
 void main() {
   test('Wrap test; toStringDeep', () {
     final RenderWrap renderWrap = RenderWrap();
@@ -153,4 +155,22 @@ void main() {
     expect(renderWrap.computeMinIntrinsicWidth(79), 80);
     expect(renderWrap.computeMinIntrinsicWidth(80), 80);
   });
+
+  test('Wrap respects clipBehavior', () {
+    const BoxConstraints viewport = BoxConstraints(maxHeight: 100.0, maxWidth: 100.0);
+    final TestClipPaintingContext context = TestClipPaintingContext();
+
+    // By default, clipBehavior should be Clip.none
+    final RenderWrap defaultWrap = RenderWrap(textDirection: TextDirection.ltr, children: <RenderBox>[box200x200]);
+    layout(defaultWrap, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+    defaultWrap.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.none));
+
+    for (final Clip clip in Clip.values) {
+      final RenderWrap wrap = RenderWrap(textDirection: TextDirection.ltr, children: <RenderBox>[box200x200], clipBehavior: clip);
+      layout(wrap, constraints: viewport, phase: EnginePhase.composite, onErrors: expectOverflowedErrors);
+      wrap.paint(context, Offset.zero);
+      expect(context.clipBehavior, equals(clip));
+    }
+  });
 }

packages/flutter/test/widgets/basic_test.dart

@@ -282,6 +282,15 @@ void main() {
     );
   });
 
+  testWidgets('UnconstrainedBox can set and update clipBehavior', (WidgetTester tester) async {
+    await tester.pumpWidget(const UnconstrainedBox());
+    final RenderUnconstrainedBox renderObject = tester.allRenderObjects.whereType<RenderUnconstrainedBox>().first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    await tester.pumpWidget(const UnconstrainedBox(clipBehavior: Clip.antiAlias));
+    expect(renderObject.clipBehavior, equals(Clip.antiAlias));
+  });
+
   group('ColoredBox', () {
     _MockCanvas mockCanvas;
     _MockPaintingContext mockContext;

packages/flutter/test/widgets/editable_text_test.dart

@@ -5020,6 +5020,48 @@ void main() {
 
     expect(RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1), SystemMouseCursors.text);
   });
+
+  testWidgets('EditableText can set and update clipBehavior', (WidgetTester tester) async {
+    await tester.pumpWidget(MediaQuery(
+      data: const MediaQueryData(devicePixelRatio: 1.0),
+      child: Directionality(
+        textDirection: TextDirection.ltr,
+        child: FocusScope(
+          node: focusScopeNode,
+          autofocus: true,
+          child: EditableText(
+            backgroundCursorColor: Colors.grey,
+            controller: controller,
+            focusNode: focusNode,
+            style: textStyle,
+            cursorColor: cursorColor,
+          ),
+        ),
+      ),
+    ));
+    final RenderEditable renderObject = tester.allRenderObjects.whereType<RenderEditable>().first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    await tester.pumpWidget(MediaQuery(
+      data: const MediaQueryData(devicePixelRatio: 1.0),
+      child: Directionality(
+        textDirection: TextDirection.ltr,
+        child: FocusScope(
+          node: focusScopeNode,
+          autofocus: true,
+          child: EditableText(
+            backgroundCursorColor: Colors.grey,
+            controller: controller,
+            focusNode: focusNode,
+            style: textStyle,
+            cursorColor: cursorColor,
+            clipBehavior: Clip.antiAlias,
+          ),
+        ),
+      ),
+    ));
+    expect(renderObject.clipBehavior, equals(Clip.antiAlias));
+  });
 }
 
 class MockTextFormatter extends TextInputFormatter {

packages/flutter/test/widgets/fitted_box_test.dart

@@ -371,6 +371,7 @@ void main() {
           height: 10.0,
           child: FittedBox(
             fit: BoxFit.cover,
+            clipBehavior: Clip.hardEdge,
             child: SizedBox(
               width: 10.0,
               height: 50.0,
@@ -393,6 +394,7 @@ void main() {
           height: 100.0,
           child: FittedBox(
             fit: BoxFit.cover,
+            clipBehavior: Clip.hardEdge,
             child: SizedBox(
               width: 50.0,
               height: 10.0,
@@ -420,6 +422,7 @@ void main() {
                   height: b,
                   child: FittedBox(
                     fit: BoxFit.none,
+                    clipBehavior: Clip.hardEdge,
                     child: SizedBox(
                       width: c,
                       height: d,
@@ -474,6 +477,15 @@ void main() {
     await tester.tap(find.byKey(key1));
     expect(_pointerDown, isTrue);
   });
+
+  testWidgets('Can set and update clipBehavior', (WidgetTester tester) async {
+    await tester.pumpWidget(FittedBox(fit: BoxFit.none, child: Container()));
+    final RenderFittedBox renderObject = tester.allRenderObjects.whereType<RenderFittedBox>().first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    await tester.pumpWidget(FittedBox(fit: BoxFit.none, child: Container(), clipBehavior: Clip.antiAlias));
+    expect(renderObject.clipBehavior, equals(Clip.antiAlias));
+  });
 }
 
 List<Type> getLayers() {

packages/flutter/test/widgets/flex_test.dart

@@ -142,4 +142,13 @@ void main() {
     final String message = tester.takeException().toString();
     expect(message, contains('\nSee also:'));
   });
+
+  testWidgets('Can set and update clipBehavior', (WidgetTester tester) async {
+    await tester.pumpWidget(Flex(direction: Axis.vertical));
+    final RenderFlex renderObject = tester.allRenderObjects.whereType<RenderFlex>().first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    await tester.pumpWidget(Flex(direction: Axis.vertical, clipBehavior: Clip.antiAlias));
+    expect(renderObject.clipBehavior, equals(Clip.antiAlias));
+  });
 }

packages/flutter/test/widgets/framework_test.dart

@@ -721,7 +721,7 @@ void main() {
       equalsIgnoringHashCodes(
         'Duplicate keys found.\n'
         'If multiple keyed nodes exist as children of another node, they must have unique keys.\n'
-        'Stack(alignment: AlignmentDirectional.topStart, textDirection: ltr, fit: loose, overflow: clip) has multiple children with key [GlobalKey#00000 problematic].'
+        'Stack(alignment: AlignmentDirectional.topStart, textDirection: ltr, fit: loose) has multiple children with key [GlobalKey#00000 problematic].'
       ),
     );
   });
@@ -891,7 +891,7 @@ void main() {
         'The specific parent that did not update after having one or more children forcibly '
         'removed due to GlobalKey reparenting is:\n'
         '- Stack(alignment: AlignmentDirectional.topStart, textDirection: ltr, fit: loose, '
-        'overflow: clip, renderObject: RenderStack#00000)\n'
+        'renderObject: RenderStack#00000)\n'
         'A GlobalKey can only be specified on one widget at a time in the widget tree.'
       ),
     );

packages/flutter/test/widgets/list_wheel_scroll_view_test.dart

@@ -13,6 +13,44 @@ import '../rendering/mock_canvas.dart';
 import '../rendering/rendering_tester.dart';
 
 void main() {
+  testWidgets('ListWheelScrollView respects clipBehavior', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      Directionality(
+        textDirection: TextDirection.ltr,
+        child: ListWheelScrollView(
+          itemExtent: 2000.0, // huge extent to trigger clip
+          children: <Widget>[Container()],
+        ),
+      ),
+    );
+
+    // 1st, check that the render object has received the default clip behavior.
+    final RenderListWheelViewport renderObject = tester.allRenderObjects.whereType<RenderListWheelViewport>().first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    // 2nd, check that the painting context has received the default clip behavior.
+    final TestClipPaintingContext context = TestClipPaintingContext();
+    renderObject.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.hardEdge));
+
+    // 3rd, pump a new widget to check that the render object can update its clip behavior.
+    await tester.pumpWidget(
+      Directionality(
+        textDirection: TextDirection.ltr,
+        child: ListWheelScrollView(
+          itemExtent: 2000.0, // huge extent to trigger clip
+          children: <Widget>[Container()],
+          clipBehavior: Clip.antiAlias,
+        ),
+      ),
+    );
+    expect(renderObject.clipBehavior, equals(Clip.antiAlias));
+
+    // 4th, check that a non-default clip behavior can be sent to the painting context.
+    renderObject.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.antiAlias));
+  });
+
   group('construction check', () {
     testWidgets('ListWheelScrollView needs positive diameter ratio', (WidgetTester tester) async {
       try {

packages/flutter/test/widgets/nested_scroll_view_test.dart

@@ -10,6 +10,8 @@ import 'package:flutter_test/flutter_test.dart';
 import 'package:flutter/gestures.dart' show DragStartBehavior;
 import 'package:flutter/rendering.dart';
 
+import '../rendering/rendering_tester.dart';
+
 class _CustomPhysics extends ClampingScrollPhysics {
   const _CustomPhysics({ ScrollPhysics parent }) : super(parent: parent);
 
@@ -120,6 +122,55 @@ Widget buildTest({
 }
 
 void main() {
+  testWidgets('NestedScrollView respects clipBehavior', (WidgetTester tester) async {
+    Widget build(NestedScrollView nestedScrollView) {
+      return Localizations(
+        locale: const Locale('en', 'US'),
+        delegates: const <LocalizationsDelegate<dynamic>>[
+          DefaultMaterialLocalizations.delegate,
+          DefaultWidgetsLocalizations.delegate,
+        ],
+        child: Directionality(
+          textDirection: TextDirection.ltr,
+          child: MediaQuery(
+            data: const MediaQueryData(),
+            child: nestedScrollView,
+          ),
+        ),
+      );
+    }
+
+    await tester.pumpWidget(build(
+      NestedScrollView(
+        headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) => <Widget>[const SliverAppBar()],
+        body: Container(height: 2000.0),
+      )
+    ));
+
+    // 1st, check that the render object has received the default clip behavior.
+    final RenderNestedScrollViewViewport renderObject = tester.allRenderObjects.whereType<RenderNestedScrollViewViewport>().first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    // 2nd, check that the painting context has received the default clip behavior.
+    final TestClipPaintingContext context = TestClipPaintingContext();
+    renderObject.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.hardEdge));
+
+    // 3rd, pump a new widget to check that the render object can update its clip behavior.
+    await tester.pumpWidget(build(
+        NestedScrollView(
+          headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) => <Widget>[const SliverAppBar()],
+          body: Container(height: 2000.0),
+          clipBehavior: Clip.antiAlias,
+        )
+    ));
+    expect(renderObject.clipBehavior, equals(Clip.antiAlias));
+
+    // 4th, check that a non-default clip behavior can be sent to the painting context.
+    renderObject.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.antiAlias));
+  });
+
   testWidgets('NestedScrollView overscroll and release and hold', (WidgetTester tester) async {
     await tester.pumpWidget(buildTest());
     expect(find.text('aaa2'), findsOneWidget);

packages/flutter/test/widgets/shrink_wrapping_viewport_test.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart';
+
+import '../rendering/rendering_tester.dart';
+
+void main() {
+  testWidgets('ShrinkWrappingViewport respects clipBehavior', (WidgetTester tester) async {
+    Widget build(ShrinkWrappingViewport child) {
+      return Directionality(
+        textDirection: TextDirection.ltr,
+        child: child,
+      );
+    }
+
+    await tester.pumpWidget(build(
+        ShrinkWrappingViewport(
+          offset: ViewportOffset.zero(),
+          slivers: <Widget>[SliverToBoxAdapter(child: Container(height: 2000.0))],
+        )
+    ));
+
+    // 1st, check that the render object has received the default clip behavior.
+    final RenderShrinkWrappingViewport renderObject = tester.allRenderObjects.whereType<RenderShrinkWrappingViewport>().first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    // 2nd, check that the painting context has received the default clip behavior.
+    final TestClipPaintingContext context = TestClipPaintingContext();
+    renderObject.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.hardEdge));
+
+    // 3rd, pump a new widget to check that the render object can update its clip behavior.
+    await tester.pumpWidget(build(
+        ShrinkWrappingViewport(
+          offset: ViewportOffset.zero(),
+          slivers: <Widget>[SliverToBoxAdapter(child: Container(height: 2000.0))],
+          clipBehavior: Clip.antiAlias,
+        )
+    ));
+    expect(renderObject.clipBehavior, equals(Clip.antiAlias));
+
+    // 4th, check that a non-default clip behavior can be sent to the painting context.
+    renderObject.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.antiAlias));
+  });
+}

packages/flutter/test/widgets/single_child_scroll_view_test.dart

@@ -10,6 +10,7 @@ import 'package:flutter_test/flutter_test.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 
+import '../rendering/rendering_tester.dart';
 import 'semantics_tester.dart';
 
 class TestScrollPosition extends ScrollPositionWithSingleContext {
@@ -39,6 +40,27 @@ class TestScrollController extends ScrollController {
 }
 
 void main() {
+  testWidgets('SingleChildScrollView respects clipBehavior', (WidgetTester tester) async {
+    await tester.pumpWidget(SingleChildScrollView(child: Container(height: 2000.0)));
+
+    // 1st, check that the render object has received the default clip behavior.
+    final dynamic renderObject = tester.allRenderObjects.where((RenderObject o) => o.runtimeType.toString() == '_RenderSingleChildViewport').first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    // 2nd, check that the painting context has received the default clip behavior.
+    final TestClipPaintingContext context = TestClipPaintingContext();
+    renderObject.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.hardEdge));
+
+    // 3rd, pump a new widget to check that the render object can update its clip behavior.
+    await tester.pumpWidget(SingleChildScrollView(clipBehavior: Clip.antiAlias, child: Container(height: 2000.0)));
+    expect(renderObject.clipBehavior, equals(Clip.antiAlias));
+
+    // 4th, check that a non-default clip behavior can be sent to the painting context.
+    renderObject.paint(context, Offset.zero);
+    expect(context.clipBehavior, equals(Clip.antiAlias));
+  });
+
   testWidgets('SingleChildScrollView control test', (WidgetTester tester) async {
     await tester.pumpWidget(SingleChildScrollView(
       child: Container(

packages/flutter/test/widgets/stack_test.dart

@@ -378,6 +378,15 @@ void main() {
     expect(renderBox.size.height, equals(12.0));
   });
 
+  testWidgets('Can set and update clipBehavior', (WidgetTester tester) async {
+    await tester.pumpWidget(Stack(textDirection: TextDirection.ltr));
+    final RenderStack renderObject = tester.allRenderObjects.whereType<RenderStack>().first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    await tester.pumpWidget(Stack(textDirection: TextDirection.ltr, clipBehavior: Clip.hardEdge));
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+  });
+
   testWidgets('IndexedStack with null index', (WidgetTester tester) async {
     bool tapped;
 
@@ -414,6 +423,7 @@ void main() {
         textDirection: TextDirection.ltr,
         child: Center(
           child: Stack(
+            clipBehavior: Clip.hardEdge,
             children: const <Widget>[
               SizedBox(
                 width: 100.0,
@@ -444,6 +454,7 @@ void main() {
         child: Center(
           child: Stack(
             overflow: Overflow.visible,
+            clipBehavior: Clip.none,
             children: const <Widget>[
               SizedBox(
                 width: 100.0,

packages/flutter/test/widgets/wrap_test.dart

@@ -735,6 +735,7 @@ void main() {
 
     await tester.pumpWidget(Wrap(
       textDirection: TextDirection.ltr,
+      clipBehavior: Clip.hardEdge,
       children: const <Widget>[
         SizedBox(width: 500.0, height: 500.0),
         SizedBox(width: 500.0, height: 500.0),
@@ -897,4 +898,13 @@ void main() {
       const Offset(0.0, 20.0),
     ]);
   });
+
+  testWidgets('Wrap can set and update clipBehavior', (WidgetTester tester) async {
+    await tester.pumpWidget(Wrap(textDirection: TextDirection.ltr));
+    final RenderWrap renderObject = tester.allRenderObjects.whereType<RenderWrap>().first;
+    expect(renderObject.clipBehavior, equals(Clip.hardEdge));
+
+    await tester.pumpWidget(Wrap(textDirection: TextDirection.ltr, clipBehavior: Clip.antiAlias));
+    expect(renderObject.clipBehavior, equals(Clip.antiAlias));
+  });
 }