Bug 262079

Summary: REGRESSION(268103@main?): [ Ventura+ arm64 wk2 ] fast/gradients/alpha-premultiplied-representable-by-unpremultiplied.html is a constant ImageOnlyFailure.
Product: WebKit Reporter: Ben Schwartz <ben_schwartz>
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: ap, bfulgham, heycam, simon.fraser, webkit-bot-watchers-bugzilla, webkit-bug-importer, zalan
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
See Also: https://bugs.webkit.org/show_bug.cgi?id=249692
https://bugs.webkit.org/show_bug.cgi?id=261477
Attachments:
Description Flags
alpha-premultiplied-representable-by-unpremultiplied-images.zip none

Description Ben Schwartz 2023-09-25 16:15:52 PDT 
Created attachment 467858 [details]
alpha-premultiplied-representable-by-unpremultiplied-images.zip

fast/gradients/alpha-premultiplied-representable-by-unpremultiplied.html

This test is a constant ImageOnlyFailure on wk2 builds on Apple Silicon machines running macOS Ventura or higher.

HISTORY:

https://results.webkit.org/?suite=layout-tests&test=fast%2Fgradients%2Falpha-premultiplied-representable-by-unpremultiplied.html&platform=mac&flavor=wk2

IMAGE DIFF:

Attached.

IMAGES URL:

https://build.webkit.org/results/Apple-Ventura-Release-AppleSilicon-WK2-Tests/268405@main%20(5116)/fast/gradients/alpha-premultiplied-representable-by-unpremultiplied-diffs.html

REPRODUCIBILITY:

I was able to reproduce this issue on macOS Ventura (13.5, 22G74/arm64) ToT using the following command:

run-webkit-tests --verbose --clobber-old-results fast/gradients/alpha-premultiplied-representable-by-unpremultiplied.html

REGRESSION:

I have marked the potential regression point as 268103@main; however, the issue reproduces in my testing environments before that point.

NOTE:

The test was last modified at 258178@main.
Comment 1 Radar WebKit Bug Importer 2023-09-25 16:16:02 PDT 
<rdar://problem/116021791>
Comment 2 EWS 2023-09-25 16:35:06 PDT 
Test gardening commit 268418@main (343f5d7b24b8): <https://commits.webkit.org/268418@main>

Reviewed commits have been landed. Closing PR #18197 and removing active labels.
Comment 3 Alexey Proskuryakov 2023-09-25 17:02:54 PDT 
This is a very subtle change in how gradients are drawn. But given that this regressed with a feature flag change, and that it WebKit2 only, it feels not entirely OK.
Comment 4 Cameron McCormack (:heycam) 2023-10-09 22:25:45 PDT 
I think this is just a slight rendering change due to enabling accelerated rendering in tests as part of enabling UI side compositing on macOS.
Comment 5 EWS 2023-11-16 15:54:55 PST 
Committed 270851@main (54a799c39b99): <https://commits.webkit.org/270851@main>

Reviewed commits have been landed. Closing PR #20617 and removing active labels.