Bug 301587 – REGRESSION(302222@main) [ Tahoe ]: 14 TestWebKitAPI.CSSViewportUnits (api-tests) are constant failures

• Component: Scrolling
• Status: RESOLVED FIXED

[Robert Jenner]

The following 14 API-tests are constant failures, observed on Tahoe:

TestWebKitAPI.CSSViewportUnits.AllSame
TestWebKitAPI.CSSViewportUnits.MaximumViewportInset
TestWebKitAPI.CSSViewportUnits.MaximumViewportInsetWithBounds
TestWebKitAPI.CSSViewportUnits.MaximumViewportInsetWithFrame
TestWebKitAPI.CSSViewportUnits.MaximumViewportInsetWithWritingMode
TestWebKitAPI.CSSViewportUnits.MaximumViewportInsetWithZoom
TestWebKitAPI.CSSViewportUnits.MinimumViewportInset
TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithBounds
TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithFrame
TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithTopContentInset
TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithWritingMode
TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithZoom
TestWebKitAPI.CSSViewportUnits.SVGDocument
TestWebKitAPI.WKScrollGeometry.ContentSizeTallerThanWebView

HISTORY:
https://results.webkit.org/?suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&suite=api-tests&test=TestWebKitAPI.CSSViewportUnits.AllSame&test=TestWebKitAPI.CSSViewportUnits.MaximumViewportInset&test=TestWebKitAPI.CSSViewportUnits.MaximumViewportInsetWithBounds&test=TestWebKitAPI.CSSViewportUnits.MaximumViewportInsetWithFrame&test=TestWebKitAPI.CSSViewportUnits.MaximumViewportInsetWithWritingMode&test=TestWebKitAPI.CSSViewportUnits.MaximumViewportInsetWithZoom&test=TestWebKitAPI.CSSViewportUnits.MinimumViewportInset&test=TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithBounds&test=TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithFrame&test=TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithTopContentInset&test=TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithWritingMode&test=TestWebKitAPI.CSSViewportUnits.MinimumViewportInsetWithZoom&test=TestWebKitAPI.CSSViewportUnits.SVGDocument&test=TestWebKitAPI.WKScrollGeometry.ContentSizeTallerThanWebView

[Radar WebKit Bug Importer]

<rdar://problem/163584974>

[Robert Jenner]

All 14 of the tests appear to have a similar failure. Here is an example of one of them:

            "name": "TestWebKitAPI.CSSViewportUnits.MaximumViewportInset",
            "output": "2025-10-28 00:06:13.613 TestWebKitAPI[9761:353541] NSEventConcurrentProcessingEnabled=NO\n\n/Volumes/Data/worker/Apple-Tahoe-Debug-Build/build/Tools/TestWebKitAPI/Tests/WebKitCocoa/CSSViewportUnits.mm:375\nExpected equality of these values:\n  fixedWidth\n    Which is: 317\n  viewportUnitLength(webView, @\"dvw\")\n    Which is: 320\n\n\n\n/Volumes/Data/worker/Apple-Tahoe-Debug-Build/build/Tools/TestWebKitAPI/Tests/WebKitCocoa/CSSViewportUnits.mm:377\nExpected equality of these values:\n  fixedWidth\n    Which is: 317\n  viewportUnitLength(webView, @\"dvmin\")\n    Which is: 320\n\n\n\n/Volumes/Data/worker/Apple-Tahoe-Debug-Build/build/Tools/TestWebKitAPI/Tests/WebKitCocoa/CSSViewportUnits.mm:380\nExpected equality of these values:\n  fixedWidth\n    Which is: 317\n  viewportUnitLength(webView, @\"dvi\")\n    Which is: 320"
        },

Every failure can be observed at the following link:
https://build.webkit.org/api/v2/logs/45420252/raw_inline

[Robert Jenner]

I have also reproduced all of these failures at macOS Tahoe Debug ToT running as follows:

run-api-tests <test_goes_here>

I have also confirmed that these tests all fail starting at 302222@main, but pass at 302221@main

So it appears that: https://commits.webkit.org/302222@main is our regression point.

[EWS]

Committed 302273@main (9d69381d1353): <https://commits.webkit.org/302273@main>

Reviewed commits have been landed. Closing PR #53119 and removing active labels.