Bug 192214

Summary:

[LFC][BFC][MarginCollapsing] Do not use computed display box values for border and padding

Product:

WebKit

Reporter:

zalan <zalan>

Component:

Layout and Rendering

Assignee:

zalan <zalan>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

bfulgham, koivisto, simon.fraser, webkit-bug-importer, zalan

Priority:

Keywords:

InRadar

Version:

WebKit Nightly Build

Hardware:

Unspecified

OS:

Unspecified

Attachments:

Description	Flags
Patch	koivisto: review+

Description zalan 2018-11-29 21:11:32 PST

they are not computed yet when we are trying to estimate margin top values. try to survive with the non-computed values.

<body><div style="float: left"></div><div><div style="margin-top: 10px">foobar</div></div>
when the floating box is placed, we need to know its final vertical position. We estimate margin tops all the way to the formatting context root. To computer margin-top for the <body>, we actually have to know if that nested div's margin gets collapsed all the way up. To find it out we need to know padding and border values. Unfortunately at the time when the float is placed we don't yet have that information.

Comment 1 zalan 2018-11-29 21:27:43 PST

Created attachment 356127 [details]
Patch

Comment 2 zalan 2018-11-30 07:22:46 PST

Committed r238735: <https://trac.webkit.org/changeset/238735>

Comment 3 Radar WebKit Bug Importer 2018-11-30 07:23:37 PST

<rdar://problem/46372648>