Bug 249987

Summary:	Inapplicable top, bottom style shouldn't affect height calculation
Product:	WebKit	Reporter:	Ahmad Saleem <ahmad.saleem792>
Component:	Layout and Rendering	Assignee:	Nobody <webkit-unassigned>
Status:	NEW ---
Severity:	Normal	CC:	bfulgham, karlcow, simon.fraser, webkit-bug-importer, zalan
Priority:	P2	Keywords:	BrowserCompat, InRadar
Version:	WebKit Nightly Build
Hardware:	Unspecified
OS:	Unspecified

Description Ahmad Saleem 2023-01-01 10:35:47 PST

Hi Team,

While going through WebKit, I came across another failing test case in Safari 16.2 & Safari Technology Preview 160 while passing in Chrome Canary 111 and Firefox Nightly 110:

Test Case - https://jsfiddle.net/vrsmce24/

Blink Commit - https://chromium.googlesource.com/chromium/blink/+/034a32ac2e53bac07e201ba7cc1d6af6ebfd3dc5

I don't know whether it is possible to merge 1-1 but just wanted to raise so we can track it.

Thanks!

Comment 1 Ahmad Saleem 2023-01-04 01:10:37 PST

Seems we need to update this: https://searchfox.org/wubkat/source/Source/WebCore/rendering/RenderBoxModelObject.cpp#286

Comment 2 Radar WebKit Bug Importer 2023-01-04 16:53:37 PST

<rdar://problem/103893875>

Comment 3 Ahmad Saleem 2023-01-25 09:47:00 PST

NOTE - This issue seems to be something similar to cache related issues, because if I refresh same tab again, it passes. Very strange!

Comment 4 Ahmad Saleem 2023-08-03 17:47:17 PDT

We have this:

https://searchfox.org/wubkat/source/Source/WebCore/rendering/RenderBoxModelObject.cpp#268

 if (isOutOfFlowPositionedWithImplicitHeight(*cb))
        return nullptr;
    

and 'isOutOfFlowPositionedWithImplicitHeight' function is exactly as this patch:

static inline bool isOutOfFlowPositionedWithImplicitHeight(const RenderBoxModelObject& child)
{
    return child.isOutOfFlowPositioned() && !child.style().logicalTop().isAuto() && !child.style().logicalBottom().isAuto();
}