Bug 203965 – Web Inspector: http/tests/inspector/target/target-events-for-provisional-page.html is flaky when running with other tests

• Status: RESOLVED
• Resolution: FIXED
• Component: Web Inspector

[Yury Semikhatsky]

http/tests/inspector/target/target-events-for-provisional-page.html

added in https://trac.webkit.org/changeset/251494/webkit

is a flakey failure when running with other tests.

Probable cause:

Some side effect of previous tests that disable PSON.

Flakiness Dashboard:

https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=http%2Ftests%2Finspector%2Ftarget%2Ftarget-events-for-provisional-page.html

[Yury Semikhatsky]

The test reliably fails when running after  http/tests/dom/new-window-can-target-opener.html.

Tools/Scripts/run-webkit-tests --no-show-results --no-retry-failures --child-processes=1 http/tests/dom/new-window-can-target-opener.html http/tests/inspector/target/target-events-for-provisional-page.html

[Radar WebKit Bug Importer]

<rdar://problem/56988642>

[Yury Semikhatsky]

The problem is that new-window-can-target-opener-win.html opened in a child window calls open() on its opener window, i.e. the test page itself (new-window-can-target-opener.html). It in turn triggers Page::setOpenedByDOMWithOpener() on the parent page. The next test will reuse the same instance of PlatformWebView and consequently the same Page in the WebProcess. Since instance of the page is the same it still has Page::openedByDOMWithOpener() == true. Because of that[1] cross-origin navigation in the next test page will reuse same process. I don't know if this is intentional behavior.

I'm going to add 
<!-- webkit-test-runner [ enableProcessSwapOnWindowOpen=true ] -->
as a temporary workaround for the flaky inspector test but we should probably never reuse a page which was openedByDOM.

[1] https://trac.webkit.org/browser/webkit/trunk/Source/WebKit/UIProcess/WebProcessPool.cpp?rev=252014#L2139

[2] https://trac.webkit.org/browser/webkit/trunk/LayoutTests/http/tests/dom/resources/new-window-can-target-opener-win.html#L19

[Yury Semikhatsky]

Created attachment 383075 [details]
Patch

[Devin Rousso]

Comment on attachment 383075 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=383075&action=review

rs=me

> LayoutTests/ChangeLog:11
> +        that may run before (the test may reuse Page instance from the previous test on which
> +        Page::openedByDOMWithOpener==true).

This seems like a bug.  Can you file a separate bug to fix this please?

[Yury Semikhatsky]

Filed https://bugs.webkit.org/show_bug.cgi?id=203981

[WebKit Commit Bot]

Comment on attachment 383075 [details]
Patch

Clearing flags on attachment: 383075

Committed r252214: <https://trac.webkit.org/changeset/252214>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.