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Merged
andycall merged 3 commits into from
Apr 3, 2026
Merged

fix(webf): guard semantics proxies and widget layout paths #905

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6cfdab6
fix(webf): skip dirty semantics proxy wrappers
andycall Apr 3, 2026
fa958e6
test(webf): drop unrelated inline assertion case
andycall Apr 3, 2026
e19fd1b
fix(webf): restore portal width and inline atomic guards
andycall Apr 3, 2026
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26 changes: 16 additions & 10 deletions webf/lib/src/css/render_style.dart
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Original file line number Diff line number Diff line change
Expand Up @@ -3378,19 +3378,25 @@ class CSSRenderStyle extends RenderStyle
maxConstraintWidth = childWrapper?.effectiveChildConstraints.maxWidth;
} catch (_) {}

if (ancestorRenderStyle.isSelfRenderWidget() &&
final RenderBoxModel? currentLayoutBoxForAncestor =
renderBoxModelInLayoutStack.isNotEmpty ? renderBoxModelInLayoutStack.last : null;
final bool ancestorIsAncestorInCurrentTree = currentLayoutBoxForAncestor == null
? true
: isRenderSubtreeAncestor(
ancestorRenderStyle.attachedRenderBoxModel,
currentLayoutBoxForAncestor,
);

if (renderStyle.isSelfRenderWidget() &&
!ancestorIsAncestorInCurrentTree &&
childWrapper != null &&
maxConstraintWidth != null &&
maxConstraintWidth.isFinite) {
logicalWidth = maxConstraintWidth;
} else if (ancestorRenderStyle.isSelfRenderWidget() &&
childWrapper != null &&
maxConstraintWidth != null &&
maxConstraintWidth.isFinite) {
final RenderBoxModel? currentLayoutBoxForAncestor =
renderBoxModelInLayoutStack.isNotEmpty ? renderBoxModelInLayoutStack.last : null;
final bool ancestorIsAncestorInCurrentTree = currentLayoutBoxForAncestor == null
? true
: isRenderSubtreeAncestor(
ancestorRenderStyle.attachedRenderBoxModel,
currentLayoutBoxForAncestor,
);

if (ancestorIsAncestorInCurrentTree) {
final double? ancestorContentLogicalWidth = ancestorRenderStyle.contentBoxLogicalWidth;
if (ancestorContentLogicalWidth != null && ancestorContentLogicalWidth.isFinite) {
Expand Down
49 changes: 27 additions & 22 deletions webf/lib/src/rendering/box_model.dart
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -120,7 +120,8 @@ bool debugRenderObjectNeedsLayout(RenderObject renderObject) {
return result;
}

bool canReuseStableProxyChildLayout(RenderBox? child, BoxConstraints constraints) {
bool canReuseStableProxyChildLayout(
RenderBox? child, BoxConstraints constraints) {
if (child == null || !child.hasSize || child.constraints != constraints) {
return false;
}
Expand Down Expand Up @@ -434,11 +435,13 @@ abstract class RenderBoxModel extends RenderBox

// Whether it needs relayout due to percentage calculation.
bool needsRelayout = false;
bool _hasPendingLayoutUpdate = true;
bool _hasPendingIntrinsicMeasurementInvalidation = true;
bool _hasPendingSubtreeIntrinsicMeasurementInvalidation = true;
String? _debugIntrinsicMeasurementDirtyReason = 'initial';
int _clearIntrinsicMeasurementInvalidationAfterLayoutPass = 1;

bool get hasPendingLayoutUpdate => _hasPendingLayoutUpdate;
bool get hasPendingIntrinsicMeasurementInvalidation =>
_hasPendingIntrinsicMeasurementInvalidation;
bool get hasPendingSubtreeIntrinsicMeasurementInvalidation =>
Expand All @@ -462,6 +465,11 @@ abstract class RenderBoxModel extends RenderBox
needsRelayout = true;
}

@protected
void clearPendingLayoutUpdateForCurrentLayoutPass() {
_hasPendingLayoutUpdate = false;
}

void markNeedsIntrinsicMeasurementUpdate([String reason = 'unspecified']) {
_hasPendingIntrinsicMeasurementInvalidation = true;
_debugIntrinsicMeasurementDirtyReason = reason;
Expand Down Expand Up @@ -525,8 +533,10 @@ abstract class RenderBoxModel extends RenderBox

@override
void layout(Constraints constraints, {bool parentUsesSize = false}) {
_lastLaidOutAsRelayoutBoundary =
!parentUsesSize || sizedByParent || constraints.isTight || parent == null;
_lastLaidOutAsRelayoutBoundary = !parentUsesSize ||
sizedByParent ||
constraints.isTight ||
parent == null;
if (renderBoxModelInLayoutStack.isEmpty) {
renderBoxModelLayoutPassId++;
}
Expand Down Expand Up @@ -649,9 +659,8 @@ abstract class RenderBoxModel extends RenderBox
// width of 0 (e.g., auto-width flex item whose only child is out-of-flow).
// In such cases, the containing block still exists, but the abspos box should size
// from its own content rather than the flex item's zero content width.
final bool isAbsOrFixed =
style.position == CSSPositionType.absolute ||
style.position == CSSPositionType.fixed;
final bool isAbsOrFixed = style.position == CSSPositionType.absolute ||
style.position == CSSPositionType.fixed;
if (isAbsOrFixed &&
style.width.isAuto &&
style.isParentRenderFlexLayout() &&
Expand Down Expand Up @@ -681,8 +690,7 @@ abstract class RenderBoxModel extends RenderBox
}
} else {
// Not in a flex context, inherit parent's content width constraint normally
double parentContentWidth =
parentFlowStyle.contentMaxConstraintsWidth;
double parentContentWidth = parentFlowStyle.contentMaxConstraintsWidth;
if (parentContentWidth != double.infinity) {
parentBoxContentConstraintsWidth = parentContentWidth;
}
Expand Down Expand Up @@ -710,7 +718,7 @@ abstract class RenderBoxModel extends RenderBox
!style.isSelfRenderReplaced() &&
style.borderBoxLogicalWidth == null &&
parentBoxContentConstraintsWidth != null) {
parentBoxContentConstraintsWidth = null;
parentBoxContentConstraintsWidth = null;
}

double? containingBlockPaddingBoxWidth;
Expand All @@ -731,12 +739,10 @@ abstract class RenderBoxModel extends RenderBox
style.minWidth.isAuto ? null : style.minWidth.computedValue;
double? maxWidth =
style.maxWidth.isNone ? null : style.maxWidth.computedValue;
double? minHeight = style.minHeight.isAuto
? null
: style.minHeight.computedValue;
double? maxHeight = style.maxHeight.isNone
? null
: style.maxHeight.computedValue;
double? minHeight =
style.minHeight.isAuto ? null : style.minHeight.computedValue;
double? maxHeight =
style.maxHeight.isNone ? null : style.maxHeight.computedValue;

double maxConstraintWidth = style.borderBoxLogicalWidth ??
parentBoxContentConstraintsWidth ??
Expand All @@ -747,9 +753,8 @@ abstract class RenderBoxModel extends RenderBox
// This handles cases where style-tree logical widths are unavailable (e.g., parent inline-block
// with auto width) but the containing block has been measured. See:
// https://www.w3.org/TR/css-position-3/#abs-non-replaced-width
final bool isAbsOrFixed =
style.position == CSSPositionType.absolute ||
style.position == CSSPositionType.fixed;
final bool isAbsOrFixed = style.position == CSSPositionType.absolute ||
style.position == CSSPositionType.fixed;
if (maxConstraintWidth == double.infinity &&
isAbsOrFixed &&
!style.isSelfRenderReplaced() &&
Expand Down Expand Up @@ -832,8 +837,7 @@ abstract class RenderBoxModel extends RenderBox
}
// Height should be not smaller than border and padding in vertical direction
// when box-sizing is border-box which is only supported.
double minConstraintHeight =
styleBorder.vertical + stylePadding.vertical;
double minConstraintHeight = styleBorder.vertical + stylePadding.vertical;
double maxConstraintHeight =
style.borderBoxLogicalHeight ?? double.infinity;

Expand Down Expand Up @@ -876,8 +880,7 @@ abstract class RenderBoxModel extends RenderBox
maxConstraintWidth =
maxConstraintWidth > maxWidth ? maxWidth : maxConstraintWidth;
// Only reduce minConstraintWidth if maxWidth is larger than border+padding requirements
double borderPadding =
styleBorder.horizontal + stylePadding.horizontal;
double borderPadding = styleBorder.horizontal + stylePadding.horizontal;
if (maxWidth >= borderPadding) {
minConstraintWidth =
minConstraintWidth > maxWidth ? maxWidth : minConstraintWidth;
Expand Down Expand Up @@ -968,6 +971,7 @@ abstract class RenderBoxModel extends RenderBox

@override
void markNeedsLayout() {
_hasPendingLayoutUpdate = true;
final RenderObject? relayoutParent = _relayoutParentOnSizeChange;
// Some wrapper parents mirror child.boxSize while laying the child out
// with parentUsesSize: false to keep a local relayout boundary.
Expand Down Expand Up @@ -1111,6 +1115,7 @@ abstract class RenderBoxModel extends RenderBox
this.contentConstraints = contentConstraints;
clearOverflowLayout();
isSelfSizeChanged = false;
clearPendingLayoutUpdateForCurrentLayoutPass();
updateIntrinsicMeasurementInvalidationForCurrentLayoutPass();

// Reset cached CSS baselines before a new layout pass. They will be
Expand Down
100 changes: 67 additions & 33 deletions webf/lib/src/rendering/box_wrapper.dart
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Original file line number Diff line number Diff line change
Expand Up @@ -97,6 +97,7 @@ class RenderLayoutBoxWrapper extends RenderBoxModel

@override
void performLayout() {
clearPendingLayoutUpdateForCurrentLayoutPass();
renderStyle.computeContentBoxLogicalWidth();
renderStyle.computeContentBoxLogicalHeight();

Expand All @@ -106,7 +107,8 @@ class RenderLayoutBoxWrapper extends RenderBoxModel
final RenderBox? c = child;
if (c == null) {
size = constraints.constrain(Size.zero);
initOverflowLayout(Rect.fromLTRB(0, 0, size.width, size.height), Rect.fromLTRB(0, 0, size.width, size.height));
initOverflowLayout(Rect.fromLTRB(0, 0, size.width, size.height),
Rect.fromLTRB(0, 0, size.width, size.height));
_lastWrapperConstraints = constraints;
_lastResolvedChildConstraints = null;
return;
Expand All @@ -127,9 +129,13 @@ class RenderLayoutBoxWrapper extends RenderBoxModel
// CSS logic already accounts for its padding/border.
} else if (c is RenderTextBox) {
// Text nodes inside wrappers should measure themselves with a sensible bound.
final double maxW = constraints.hasBoundedWidth ? constraints.maxWidth : double.infinity;
final double maxH = constraints.hasBoundedHeight ? constraints.maxHeight : double.infinity;
childConstraints = BoxConstraints(minWidth: 0, maxWidth: maxW, minHeight: 0, maxHeight: maxH);
final double maxW =
constraints.hasBoundedWidth ? constraints.maxWidth : double.infinity;
final double maxH = constraints.hasBoundedHeight
? constraints.maxHeight
: double.infinity;
childConstraints = BoxConstraints(
minWidth: 0, maxWidth: maxW, minHeight: 0, maxHeight: maxH);
} else {
// Fallback: provide loose, unbounded constraints so inner WebF render boxes
// can compute their own CSS-based constraints without being forced to expand.
Expand Down Expand Up @@ -158,7 +164,8 @@ class RenderLayoutBoxWrapper extends RenderBoxModel
}
if (minW > maxW) minW = maxW;
if (minH > maxH) minH = maxH;
return BoxConstraints(minWidth: minW, maxWidth: maxW, minHeight: minH, maxHeight: maxH);
return BoxConstraints(
minWidth: minW, maxWidth: maxW, minHeight: minH, maxHeight: maxH);
}

childConstraints = intersect(childConstraints, constraints);
Expand All @@ -176,7 +183,8 @@ class RenderLayoutBoxWrapper extends RenderBoxModel
// Use sibling-oriented collapsed margins so the inter-item spacing equals
// the CSS collapsed result between previous bottom and current top.
final double childMarginTop = renderStyle.collapsedMarginTopForSibling;
final double childMarginBottom = renderStyle.collapsedMarginBottomForSibling;
final double childMarginBottom =
renderStyle.collapsedMarginBottomForSibling;
final double childMarginLeft = renderStyle.marginLeft.computedValue;
final double childMarginRight = renderStyle.marginRight.computedValue;

Expand All @@ -186,34 +194,47 @@ class RenderLayoutBoxWrapper extends RenderBoxModel
// elements where content can extend beyond the box; for clipping containers
// the intermediate RenderLayoutBoxWrapper (created for the Scrollable chain)
// never propagates scrollableSize, leaving it at Size.zero.
final bool isClippingContainer = c.renderStyle.effectiveOverflowX != CSSOverflowType.visible ||
c.renderStyle.effectiveOverflowY != CSSOverflowType.visible;
final Size contentScrollable = isClippingContainer ? c.size : c.scrollableSize;
final bool isClippingContainer =
c.renderStyle.effectiveOverflowX != CSSOverflowType.visible ||
c.renderStyle.effectiveOverflowY != CSSOverflowType.visible;
final Size contentScrollable =
isClippingContainer ? c.size : c.scrollableSize;

// Decide sizing based on list axis. In a horizontal list (unbounded width),
// widen by left+right margins so gaps appear between items. In a vertical
// list (unbounded height), increase height by top+bottom margins.
final bool isHorizontalList = constraints.hasBoundedHeight && !constraints.hasBoundedWidth;
final bool isVerticalList = constraints.hasBoundedWidth && !constraints.hasBoundedHeight;
final bool isHorizontalList =
constraints.hasBoundedHeight && !constraints.hasBoundedWidth;
final bool isVerticalList =
constraints.hasBoundedWidth && !constraints.hasBoundedHeight;

double wrapperWidth;
double wrapperHeight;
if (isHorizontalList) {
wrapperWidth = contentScrollable.width + childMarginLeft + childMarginRight;
wrapperWidth =
contentScrollable.width + childMarginLeft + childMarginRight;
// Height is tight from the viewport; still offset child by vertical margins below.
wrapperHeight = constraints.hasBoundedHeight ? constraints.maxHeight : (contentScrollable.height + childMarginTop + childMarginBottom);
wrapperHeight = constraints.hasBoundedHeight
? constraints.maxHeight
: (contentScrollable.height + childMarginTop + childMarginBottom);
} else if (isVerticalList) {
wrapperWidth = constraints.hasBoundedWidth ? constraints.maxWidth : (contentScrollable.width + childMarginLeft + childMarginRight);
wrapperHeight = contentScrollable.height + childMarginTop + childMarginBottom;
wrapperWidth = constraints.hasBoundedWidth
? constraints.maxWidth
: (contentScrollable.width + childMarginLeft + childMarginRight);
wrapperHeight =
contentScrollable.height + childMarginTop + childMarginBottom;
} else {
// Fallback (no tightness info): include both margins conservatively.
wrapperWidth = contentScrollable.width + childMarginLeft + childMarginRight;
wrapperHeight = contentScrollable.height + childMarginTop + childMarginBottom;
wrapperWidth =
contentScrollable.width + childMarginLeft + childMarginRight;
wrapperHeight =
contentScrollable.height + childMarginTop + childMarginBottom;
}

size = constraints.constrain(Size(wrapperWidth, wrapperHeight));

if (renderStyle.isSelfPositioned() || renderStyle.isSelfStickyPosition()) {
if (renderStyle.isSelfPositioned() ||
renderStyle.isSelfStickyPosition()) {
CSSPositionedLayout.applyPositionedChildOffset(this, c);
} else {
// Offset the child within the wrapper by its margins
Expand All @@ -226,7 +247,8 @@ class RenderLayoutBoxWrapper extends RenderBoxModel
}

calculateBaseline();
initOverflowLayout(Rect.fromLTRB(0, 0, size.width, size.height), Rect.fromLTRB(0, 0, size.width, size.height));
initOverflowLayout(Rect.fromLTRB(0, 0, size.width, size.height),
Rect.fromLTRB(0, 0, size.width, size.height));
}

@override
Expand All @@ -241,17 +263,22 @@ class RenderLayoutBoxWrapper extends RenderBoxModel

@override
bool hitTest(BoxHitTestResult result, {required Offset position}) {
if (!hasSize || !contentVisibilityHitTest(result, position: position) || renderStyle.isVisibilityHidden) {
if (!hasSize ||
!contentVisibilityHitTest(result, position: position) ||
renderStyle.isVisibilityHidden) {
return false;
}

assert(() {
if (!hasSize) {
if (debugNeedsLayout) {
throw FlutterError.fromParts(<DiagnosticsNode>[
ErrorSummary('Cannot hit test a render box that has never been laid out.'),
describeForError('The hitTest() method was called on this RenderBox'),
ErrorDescription("Unfortunately, this object's geometry is not known at this time, "
ErrorSummary(
'Cannot hit test a render box that has never been laid out.'),
describeForError(
'The hitTest() method was called on this RenderBox'),
ErrorDescription(
"Unfortunately, this object's geometry is not known at this time, "
'probably because it has never been laid out. '
'This means it cannot be accurately hit-tested.'),
ErrorHint('If you are trying '
Expand All @@ -263,7 +290,8 @@ class RenderLayoutBoxWrapper extends RenderBoxModel
throw FlutterError.fromParts(<DiagnosticsNode>[
ErrorSummary('Cannot hit test a render box with no size.'),
describeForError('The hitTest() method was called on this RenderBox'),
ErrorDescription('Although this node is not marked as needing layout, '
ErrorDescription(
'Although this node is not marked as needing layout, '
'its size is not set.'),
ErrorHint('A RenderBox object must have an '
'explicit size before it can be hit-tested. Make sure '
Expand All @@ -283,14 +311,18 @@ class RenderLayoutBoxWrapper extends RenderBoxModel
}

final BoxParentData childParentData = child!.parentData as BoxParentData;
bool isHit = result.addWithPaintOffset(offset: childParentData.offset, position: position, hitTest: (result, position) {
// addWithPaintOffset is to add an offset to the child node, the calculation itself does not need to bring an offset.
if (hasSize && hitTestChildren(result, position: position) || hitTestSelf(position)) {
result.add(BoxHitTestEntry(this, position));
return true;
}
return false;
});
bool isHit = result.addWithPaintOffset(
offset: childParentData.offset,
position: position,
hitTest: (result, position) {
// addWithPaintOffset is to add an offset to the child node, the calculation itself does not need to bring an offset.
if (hasSize && hitTestChildren(result, position: position) ||
hitTestSelf(position)) {
result.add(BoxHitTestEntry(this, position));
return true;
}
return false;
});
return isHit;
}

Expand All @@ -304,7 +336,9 @@ class RenderLayoutBoxWrapper extends RenderBoxModel
class LayoutBoxWrapper extends SingleChildRenderObjectWidget {
final dom.Element ownerElement;

const LayoutBoxWrapper({super.key, required Widget child, required this.ownerElement}) : super(child: child);
const LayoutBoxWrapper(
{super.key, required Widget child, required this.ownerElement})
: super(child: child);

@override
RenderObject createRenderObject(BuildContext context) {
Expand Down
1 change: 1 addition & 0 deletions webf/lib/src/rendering/event_listener.dart
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -175,6 +175,7 @@ class RenderEventListener extends RenderBoxModel

@override
void performLayout() {
clearPendingLayoutUpdateForCurrentLayoutPass();
updateIntrinsicMeasurementInvalidationForCurrentLayoutPass();
final RenderBox? currentChild = child;
if (hasSize &&
Expand Down
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