[webkit-changes] [WebKit/WebKit] 208379: margin-top is ignored on elements with zero-height...

[Alan Baradlay]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 208379f2adf1bbffc31b6094633c5cd0863a8210
      https://github.com/WebKit/WebKit/commit/208379f2adf1bbffc31b6094633c5cd0863a8210
  Author: Alan Baradlay <zalan at apple.com>
  Date:   2023-03-21 (Tue, 21 Mar 2023)

  Changed paths:
    A LayoutTests/fast/block/float/float-clear-with-self-collpasing-box-expected.html
    A LayoutTests/fast/block/float/float-clear-with-self-collpasing-box.html
    M Source/WebCore/rendering/RenderBlockFlow.cpp
    M Source/WebCore/rendering/RenderBlockFlow.h

  Log Message:
  -----------
  margin-top is ignored on elements with zero-height (and clear set) if they appear after floating elements
https://bugs.webkit.org/show_bug.cgi?id=197162
<rdar://problem/50098403>

Reviewed by Antti Koivisto.

Just because a block box has 'clear' does not necessarily mean it also introduces clearance. It could very well be below
all the floats through the normal inflow block positioning. In such cases we should not adjust the block container's bottom.

* Source/WebCore/rendering/RenderBlockFlow.cpp:
(WebCore::RenderBlockFlow::selfCollapsingMarginBeforeWithClear):
(WebCore::RenderBlockFlow::collapseMarginsWithChildInfo):
(WebCore::RenderBlockFlow::handleAfterSideOfBlock):
* Source/WebCore/rendering/RenderBlockFlow.h:

Canonical link: https://commits.webkit.org/261926@main