Bug 152821

Summary:	REGRESSION(r189947): [GTK] css-multicol-1 tests failing
Product:	WebKit	Reporter:	Michael Catanzaro <mcatanzaro>
Component:	Layout and Rendering	Assignee:	Nobody <webkit-unassigned>
Status:	RESOLVED DUPLICATE
Severity:	Normal	CC:	bugs-noreply, clopez, mcatanzaro, simon.fraser
Priority:	P2
Version:	Other
Hardware:	PC
OS:	Linux

Description Michael Catanzaro 2016-01-06 17:19:38 PST

The following tests have been failing for GTK since r188947:

imported/w3c/css/css-multicol-1/multicol-basic-001.html [ ImageOnlyFailure ]
imported/w3c/css/css-multicol-1/multicol-basic-002.html [ ImageOnlyFailure ]
imported/w3c/css/css-multicol-1/multicol-basic-003.html [ ImageOnlyFailure ]
imported/w3c/css/css-multicol-1/multicol-basic-004.html [ ImageOnlyFailure ]
imported/w3c/css/css-multicol-1/multicol-rule-002.xht [ ImageOnlyFailure ]
imported/w3c/css/css-multicol-1/multicol-rule-px-001.xht [ ImageOnlyFailure ]
imported/w3c/css/css-multicol-1/multicol-rule-stacking-001.xht [ ImageOnlyFailure ]
imported/w3c/css/css-multicol-1/multicol-shorthand-001.xht [ ImageOnlyFailure ]
imported/w3c/css/css-multicol-1/multicol-span-all-block-sibling-003.xht [ ImageOnlyFailure ]
imported/w3c/css/css-multicol-1/multicol-span-all-margin-nested-firstchild-001.xht [ ImageOnlyFailure ]

I should note that all the .xht tests print the word "FAIL FAIL FAIL" repeatedly, but the expected results include "FAIL FAIL FAIL" as well, so that problem is unrelated to this bug. That is probably that we are treating the .xht files as HTML rather than XHTML, bug #152455. In this bug I am only concerned with the pixel differences introduced by r188947.

I have no clue why r188947 fixed pixel differences on Macs but introduced them on Linux.

Comment 1 Simon Fraser (smfr) 2016-01-06 17:21:50 PST

Do you mean http://trac.webkit.org/changeset/188947? That's an accessibility change.

Comment 2 Michael Catanzaro 2016-01-06 17:23:24 PST

The revision number in my first post is a typo. These failures were introduced by r189947, not r188947.

Comment 3 Michael Catanzaro 2016-07-23 11:06:45 PDT

These tests were actually flaky, but only passed rarely. Since enabling threaded compositor, they're passing about half the time. Updating expectations accordingly.

Comment 4 Carlos Alberto Lopez Perez 2020-01-15 06:28:14 PST

The failures on this tests were caused because of antialiasing the Ahem font.
Once antialiasing its disabled for Ahem, the tests pass.

*** This bug has been marked as a duplicate of bug 204671 ***