css3/filters/effect-contrast-hw.html is a constant image only failure on iOS 16 release running on Apple Silicon only. HISTORY: https://results.webkit.org/?suite=layout-tests&test=css3%2Ffilters%2Feffect-contrast-hw.html&architecture=arm64 IMAGE DIFF URL: https://build.webkit.org/results/Apple-iOS-16-Simulator-Release-arm64-WK2-Tests/259102@main%20(754)/css3/filters/effect-contrast-hw-diffs.html image diff images attached to bug.
Created attachment 464571 [details] Image Diffs for Failing Test
I was able to reproduce this failure on my Apple Silicon Mac at iOS 16 Release ToT running the test as follows: Run-Webkit-Tests css3/filters/effect-contrast-hw.html Scrolling backwards in the history, it appears this test has been a constant image failure since we started running testing on iOS 16.
<rdar://problem/104456051>
This is a curious diff - it's not the colors that are different, but box sizes! Are contrast filters doing the wrong thing at the edges?
It's possible the CoreAnimation's contrast filter has slightly different behavior. But I think it's OK to just increase the pixel tolerance here.
Hmm, isn't this going to create user visible cracks in page layout when this filter is used?
Pull request: https://github.com/WebKit/WebKit/pull/8897
Test gardening commit 259154@main (9770e5c864b4): <https://commits.webkit.org/259154@main> Reviewed commits have been landed. Closing PR #8897 and removing active labels.
It appears that this test has been a constant image only failure on iOS 16 simulator running only on an Apple Silicon machine since this test was introduced at : https://commits.webkit.org/254408@main