467321 - {inc}[MARGIN-C]Inconsistent layout with small margin-bottom (e.g. with <hr>)

Status: RESOLVED WORKSFORME

(Core :: Layout: Block and Inline, defect)

Description

[Jesse Ruderman]

The testcase and reference have the same final DOM, so they should look the same.

Based on layout/reftests/bugs/200774-1.html.  The original testcase had an <hr>, but I reduced it to a <div> with height and margin-bottom styles.

Comment 1

[Jesse Ruderman]

Attachment: testcase (dynamic)

Comment 2

[Jesse Ruderman]

Attachment: reference (static)

Comment 3

[Daniel Holbert [:dholbert]]

Bug appears on Linux, too.  (testcase has less space between "B" and "C" than reference case)

Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1b3pre) Gecko/20081129 Minefield/3.1b3pre ID:20081129020839

Comment 4

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Is this a regression?

Comment 5

[Daniel Holbert [:dholbert]]

Yes, it is a regression WRT Firefox 2.
Firefox 3.0.4 shows the bug.
Firefox 2.0.0.18 doesn't show the bug.

Comment 6

[(mostly gone) XtC4UaLL [:xtc4uall]]

works:
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b2pre) Gecko/2007120205 Minefield/3.0b2pre ID:2007120205
fails:
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b2pre) Gecko/2007120305 Minefield/3.0b2pre ID:2007120305

=> range:
http://bonsai.mozilla.org/cvsquery.cgi?treeid=default&module=all&branch=HEAD&branchtype=match&dir=&file=&filetype=match&who=&whotype=match&sortby=Date&hours=2&date=explicit&mindate=2007-12-02+02%3A00&maxdate=2007-12-03+04%3A00&cvsroot=%2Fcvsroot

Comment 7

[Jesse Ruderman]

Attachment: testcase 2 (dynamic)

I think this is clearer than the first testcase-reference pair.

Comment 8

[Jesse Ruderman]

Attachment: reference 2 (static)

Comment 9

[Jesse Ruderman]

dholbert, it would be great if you could fix this like you did for bug 405517, bug 418766, and bug 421239.  This is the kind of thing that refdyn tends to hit over and over again.

Comment 10

[Daniel Holbert [:dholbert]]

Cool, I'll take a look. (This could be a regression from bug 405517, too.)

Comment 11

[Daniel Holbert [:dholbert]]

Yup, regression from bug 405517 -- confirmed by taking a checkout from just before that patch landed and then applying the patch manually. :-/

Comment 12

[Daniel Holbert [:dholbert]]

FWIW, I tried reverting bug 405517's patch and applying the older patch from that bug in its place, per my comment at the end of bug 405517 comment 11.  (using an up-to-date mozilla-central build)

However, that change breaks 2 reftests: text/444656.html and margin-collapsing/block-abs-pos-1.html

Comment 13

[Jesse Ruderman]

WFM

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.3a1pre) Gecko/20091008 Firefox/3.7a1pre

Comment 14

[Jesse Ruderman]

reftest:
http://hg.mozilla.org/mozilla-central/rev/c8a743c6f944