Bug 315398 – REGRESSION(312765@main): [macOS Release] http/tests/site-isolation/accessibility/client/simple-iframe.html is a constant TIMEOUT

• Component: WebKit Misc.
• Status: NEW

[Karl Rackler]

Description:
http/tests/site-isolation/accessibility/client/simple-iframe.html is a constant TIMEOUT on mac macOS Release

Regression = https://commits.webkit.org/compare/312763@main...312766@main

312765@main AXIsolatedTree is exactly the cross-process AX tree used when a child iframe is in a different process. "Skip work when no changes are pending" is the way to break a notify-done contract — if a "no changes pending" branch is hit at the wrong moment, the parent never gets the AX update from the iframe and notifyDone is never called.

This issue can be bisected to 312765@main using the command:
run-webkit-tests --no-build --no-retry --no-show-results --exit-after-n-failures=1 --expect-pass --iterations=5 --force --release http/tests/site-isolation/accessibility/client/simple-iframe.html

------------- BISECTION AUDIT TRAIL -------------
312490@main, 0f4e435819e7 --> Passed
312639@main, 41568db3548f --> Passed
312705@main, a930513ff6bb --> Passed
312757@main, 9c272d7dbe94 --> Passed
312760@main, e013a1f98e85 --> Passed
312763@main, 82e8e98e3f73 --> Passed
312766@main, 82e8e98e3f73 --> TIMEOUT (matches) [bot os version: 25E200, 25E260]
312767@main, 82e8e98e3f73 --> TIMEOUT (matches) [bot os version: 25E200, 25E260]
312768@main, 82e8e98e3f73 --> TIMEOUT (matches) [bot os version: 25E260]
312787@main, 1f804ec554e3 --> TIMEOUT (matches) [bot os version: 25E260]
312808@main, 2301d3a6e99a --> TIMEOUT (matches) [bot os version: 25E260]
313066@main, 903aebfeea77 --> TIMEOUT (matches) [bot os version: 25E260]
313697@main, 7d41f6f65e00 --> TIMEOUT [bot os version: 25E200, 25E260]
313699@main, bb6cd1b1508d --> TIMEOUT [bot os version: 25E260]
313738@main, fe511c676864 --> TIMEOUT (matches, 6/6) [bot os version: 25E260]
313738@main, fe511c676864 --> TIMEOUT (matches, 6/6) [bot os version: 25E260]
------------- BISECTION AUDIT TRAIL END -------------

History:
https://results.webkit.org/?version_name=Tahoe&suite=layout-tests&test=http%2Ftests%2Fsite-isolation%2Faccessibility%2Fclient%2Fsimple-iframe.html

Diff:
--- 
+++ 
@@ -1,11 +1,4 @@
-Dump accessibility tree with isolated iframe
-AXRole: AXWebArea
-    AXRole: AXButton Before
-    AXRole: AXWebArea
-        AXRole: AXHeading Hello, world!
-    AXRole: AXButton After
+CONSOLE MESSAGE: Unhandled Promise Rejection: Timed out
+FAIL: Timed out waiting for notifyDone to be called
 
-PASS successfullyParsed is true
-
-TEST COMPLETE
 Before    After

Test Run: https://build.webkit.org/#/builders/1716/builds/4106
08:24:57.753 23313 [26830/91997] http/tests/site-isolation/accessibility/client/simple-iframe.html failed unexpectedly (test timed out, text diff)
08:24:57.861 23313 worker/10 http/tests/site-isolation/accessibility/client/simple-iframe.html failed:

[Radar WebKit Bug Importer]

<rdar://problem/177751156>

[EWS]

Test gardening commit 313767@main (b1c6b4bda27f): <https://commits.webkit.org/313767@main>

Reviewed commits have been landed. Closing PR #65514 and removing active labels.