Title: [239331] trunk/Source/WebCore
- Revision
- 239331
- Author
- [email protected]
- Date
- 2018-12-18 07:23:47 -0800 (Tue, 18 Dec 2018)
Log Message
[LFC][BFC][MarginCollapsing] Expand marginAfterCollapsesWithNextSibling and marginBeforeCollapsesWithPreviousSibling collapsing logic
https://bugs.webkit.org/show_bug.cgi?id=192791
Reviewed by Antti Koivisto.
* layout/blockformatting/BlockMarginCollapse.cpp:
(WebCore::Layout::BlockFormattingContext::Geometry::MarginCollapse::marginBeforeCollapsesWithPreviousSibling):
(WebCore::Layout::BlockFormattingContext::Geometry::MarginCollapse::marginAfterCollapsesWithNextSibling):
Modified Paths
Diff
Modified: trunk/Source/WebCore/ChangeLog (239330 => 239331)
--- trunk/Source/WebCore/ChangeLog 2018-12-18 15:19:21 UTC (rev 239330)
+++ trunk/Source/WebCore/ChangeLog 2018-12-18 15:23:47 UTC (rev 239331)
@@ -1,5 +1,16 @@
2018-12-18 Zalan Bujtas <[email protected]>
+ [LFC][BFC][MarginCollapsing] Expand marginAfterCollapsesWithNextSibling and marginBeforeCollapsesWithPreviousSibling collapsing logic
+ https://bugs.webkit.org/show_bug.cgi?id=192791
+
+ Reviewed by Antti Koivisto.
+
+ * layout/blockformatting/BlockMarginCollapse.cpp:
+ (WebCore::Layout::BlockFormattingContext::Geometry::MarginCollapse::marginBeforeCollapsesWithPreviousSibling):
+ (WebCore::Layout::BlockFormattingContext::Geometry::MarginCollapse::marginAfterCollapsesWithNextSibling):
+
+2018-12-18 Zalan Bujtas <[email protected]>
+
[LFC][BFC][MarginCollapsing] Expand marginAfterCollapsesWithParentMarginAfter and marginBeforeCollapsesWithParentMarginBefore collapsing logic
https://bugs.webkit.org/show_bug.cgi?id=192787
Modified: trunk/Source/WebCore/layout/blockformatting/BlockMarginCollapse.cpp (239330 => 239331)
--- trunk/Source/WebCore/layout/blockformatting/BlockMarginCollapse.cpp 2018-12-18 15:19:21 UTC (rev 239330)
+++ trunk/Source/WebCore/layout/blockformatting/BlockMarginCollapse.cpp 2018-12-18 15:23:47 UTC (rev 239331)
@@ -290,15 +290,30 @@
{
ASSERT(layoutBox.isBlockLevelBox());
- if (layoutBox.isFloatingPositioned())
+ if (!layoutBox.previousInFlowSibling())
return false;
- if (!layoutBox.isPositioned() || layoutBox.isInFlowPositioned())
- return true;
+ auto& previousInFlowSibling = *layoutBox.previousInFlowSibling();
- // Out of flow positioned.
- ASSERT(layoutBox.isOutOfFlowPositioned());
- return layoutBox.style().top().isAuto();
+ // Margins between a floated box and any other box do not collapse.
+ if (layoutBox.isFloatingPositioned() || previousInFlowSibling.isFloatingPositioned())
+ return false;
+
+ // Margins of absolutely positioned boxes do not collapse.
+ if ((layoutBox.isOutOfFlowPositioned() && !layoutBox.style().top().isAuto())
+ || (previousInFlowSibling.isOutOfFlowPositioned() && !previousInFlowSibling.style().bottom().isAuto()))
+ return false;
+
+ // Margins of inline-block boxes do not collapse.
+ if (layoutBox.isInlineBlockBox() || previousInFlowSibling.isInlineBlockBox())
+ return false;
+
+ // The bottom margin of an in-flow block-level element always collapses with the top margin of
+ // its next in-flow block-level sibling, unless that sibling has clearance.
+ if (hasClearance(layoutBox))
+ return false;
+
+ return true;
}
bool BlockFormattingContext::Geometry::MarginCollapse::marginAfterCollapsesWithNextSibling(const Box& layoutBox)
@@ -305,15 +320,10 @@
{
ASSERT(layoutBox.isBlockLevelBox());
- if (layoutBox.isFloatingPositioned())
+ if (!layoutBox.nextInFlowSibling())
return false;
- if (!layoutBox.isPositioned() || layoutBox.isInFlowPositioned())
- return true;
-
- // Out of flow positioned.
- ASSERT(layoutBox.isOutOfFlowPositioned());
- return layoutBox.style().bottom().isAuto();
+ return marginBeforeCollapsesWithPreviousSibling(*layoutBox.nextInFlowSibling());
}
bool BlockFormattingContext::Geometry::MarginCollapse::marginsCollapseThrough(const Box& layoutBox)
_______________________________________________
webkit-changes mailing list
[email protected]
https://lists.webkit.org/mailman/listinfo/webkit-changes
