Changeset 287064 in webkit

Timestamp:

Dec 15, 2021 1:03:52 AM (7 months ago)

Author:

svillar@igalia.com

Message:

[css-flexbox] Absolutely positioned children should be aligned using the margin box
​https://bugs.webkit.org/show_bug.cgi?id=234244

Reviewed by Darin Adler.

LayoutTests/imported/w3c:

• web-platform-tests/css/css-flexbox/abspos/position-absolute-014-expected.txt: Replaced FAIL

by PASS expectations.

Source/WebCore:

When aligning absolutely positioned children we must use the child's margin box. We were
using the border box instead, and thus ignoring margins when aligning absolutely positioned
flexbox children.

This fixes position-absolute-014.html from the WPT suite.

• rendering/RenderFlexibleBox.cpp:

(WebCore::RenderFlexibleBox::availableAlignmentSpaceForChild): Removed the !isOutOfFlowPositioned()
ASSERT. It's true that in the past it was called only from code dealing with flex items but the code
implementing the function does not really have that restriction at all.
(WebCore::RenderFlexibleBox::staticCrossAxisPositionForPositionedChild): Directly call
availableAlignmentSpaceForChild() as it already uses the margin box.

Location:

trunk

Files:

• LayoutTests/imported/w3c/ChangeLog (modified) (1 diff)
• LayoutTests/imported/w3c/web-platform-tests/css/css-flexbox/abspos/position-absolute-014-expected.txt (modified) (1 diff)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/RenderFlexibleBox.cpp (modified) (2 diffs)

trunk/LayoutTests/imported/w3c/ChangeLog

@@ +1 @@
+2021-12-13  Sergio Villar Senin  <svillar@igalia.com>
+
+        [css-flexbox] Absolutely positioned children should be aligned using the margin box
+        https://bugs.webkit.org/show_bug.cgi?id=234244
+
+        Reviewed by Darin Adler.
+
+        * web-platform-tests/css/css-flexbox/abspos/position-absolute-014-expected.txt: Replaced FAIL
+        by PASS expectations.
+
 2021-12-14  Joonghun Park  <jh718.park@samsung.com>
 

trunk/LayoutTests/imported/w3c/web-platform-tests/css/css-flexbox/abspos/position-absolute-014-expected.txt

@@ -1 +1 @@
 aaa bbb aaa bbb aaa bbb
 
-FAIL The bottom of each pair of boxes should be the same assert_equals: expected 166 but got 106
+PASS The bottom of each pair of boxes should be the same
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2021-12-13  Sergio Villar Senin  <svillar@igalia.com>
+
+        [css-flexbox] Absolutely positioned children should be aligned using the margin box
+        https://bugs.webkit.org/show_bug.cgi?id=234244
+
+        Reviewed by Darin Adler.
+
+        When aligning absolutely positioned children we must use the child's margin box. We were
+        using the border box instead, and thus ignoring margins when aligning absolutely positioned
+        flexbox children.
+
+        This fixes position-absolute-014.html from the WPT suite.
+
+        * rendering/RenderFlexibleBox.cpp:
+        (WebCore::RenderFlexibleBox::availableAlignmentSpaceForChild): Removed the !isOutOfFlowPositioned()
+        ASSERT. It's true that in the past it was called only from code dealing with flex items but the code
+        implementing the function does not really have that restriction at all.
+        (WebCore::RenderFlexibleBox::staticCrossAxisPositionForPositionedChild): Directly call
+        availableAlignmentSpaceForChild() as it already uses the margin box.
+
 2021-12-14  Joonghun Park  <jh718.park@samsung.com>
 

trunk/Source/WebCore/rendering/RenderFlexibleBox.cpp

@@ -1225 +1225 @@
 LayoutUnit RenderFlexibleBox::availableAlignmentSpaceForChild(LayoutUnit lineCrossAxisExtent, const RenderBox& child)
 {
-    ASSERT(!child.isOutOfFlowPositioned());
     LayoutUnit childCrossExtent = crossAxisMarginExtentForChild(child) + crossAxisExtentForChild(child);
     return lineCrossAxisExtent - childCrossExtent;
@@ -1685 +1684 @@
 LayoutUnit RenderFlexibleBox::staticCrossAxisPositionForPositionedChild(const RenderBox& child)
 {
-    LayoutUnit availableSpace = crossAxisContentExtent() - crossAxisExtentForChild(child);
+    auto availableSpace = availableAlignmentSpaceForChild(crossAxisContentExtent(), child);
     return alignmentOffset(availableSpace, alignmentForChild(child), 0_lu, 0_lu, style().flexWrap() == FlexWrap::Reverse);
 }