Bug 242194 – REGRESSION (251723@main): [ iOS ] compositing/images/positioned-image-content-rect.html is a flaky image failure

• Status: NEW
• Component: Compositing

[Karl Rackler]

Description:
compositing/images/positioned-image-content-rect.html

The first failure that I saw on the dashboard was on 6/21/2022 at 251723@main.

History:
https://results.webkit.org/?suite=layout-tests&test=compositing%2Fimages%2Fpositioned-image-content-rect.html&platform=ios&limit=50000

Image Diff:
https://build.webkit.org/results/Apple-iOS-15-Simulator-Release-arm64-WK2-Tests/251723@main%20(94)/compositing/images/positioned-image-content-rect-diffs.html

[Radar WebKit Bug Importer]

<rdar://problem/96230716>

[Karl Rackler]

REPRODUCTION STEPS
I can reproduce this on 251723@main, but unable to reproduce it on 251722@main or earlier.

Command: 
run-webkit-tests --ios-simulator --debug --exit-after-n-failures 1 --exit-after-n-crashes-or-timeouts 1 --iterations 50 --no-retry compositing/images/positioned-image-content-rect.html

Result: 
Unexpected flakiness: image-only failures (1)
  compositing/images/positioned-image-content-rect.html [ ImageOnlyFailure Pass ]

[Karl Rackler]

I have marked this test as a flaky image failure while this issue is investigated.

[EWS]

Test gardening commit 252003@main (769fc294900a): <https://commits.webkit.org/252003@main>

Reviewed commits have been landed. Closing PR #1953 and removing active labels.

[Alexey Proskuryakov]

Looks like an antialiasing or upscaling issue.

Would there be any problem with reverting 251723@main?

[Simon Fraser (smfr)]

Looks like one is a non-Retina image. Possibly affected by an earlier test in the sequence.

[Alexey Proskuryakov]

> Would there be any problem with reverting 251723@main?

I didn't try, but it seems unlikely that it can be reverted cleanly, because of 251965@main.