Bug 186372

Summary:	Layout Test js/error-should-not-strong-reference-global-object.html is a flaky failure
Product:	WebKit	Reporter:	Ryan Haddad <ryanhaddad>
Component:	JavaScriptCore	Assignee:	Mark Lam <mark.lam>
Status:	RESOLVED FIXED
Severity:	Normal	CC:	ap, keith_miller, mark.lam, realdawei, simon.fraser, webkit-bug-importer
Priority:	P2	Keywords:	InRadar
Version:	Other
Hardware:	Unspecified
OS:	Unspecified
See Also:	https://bugs.webkit.org/show_bug.cgi?id=185996 https://bugs.webkit.org/show_bug.cgi?id=187103

Description Ryan Haddad 2018-06-06 17:45:21 PDT

The following layout test is flaky on iOS and macOS

js/error-should-not-strong-reference-global-object.html

Probable cause:

This test was added with https://trac.webkit.org/changeset/232314/webkit and appears to have been flaky since the start.

Flakiness Dashboard:

https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=js%2Ferror-should-not-strong-reference-global-object.html

--- /Volumes/Data/slave/highsierra-release-tests-wk1/build/layout-test-results/js/error-should-not-strong-reference-global-object-expected.txt
+++ /Volumes/Data/slave/highsierra-release-tests-wk1/build/layout-test-results/js/error-should-not-strong-reference-global-object-actual.txt
@@ -1,4 +1,5 @@
-PASS successfullyParsed is true
+CONSOLE MESSAGE: line 46: Error: There are more global objects than there should be
+FAIL successfullyParsed should be true (of type boolean). Was undefined (of type undefined).
 
 TEST COMPLETE

Comment 1 Ryan Haddad 2018-06-13 11:53:30 PDT

The test is terribly flaky and making the bots red. Keith, would you take a look at this? We need to fix the test or roll out the change.

Comment 2 Ryan Haddad 2018-06-13 12:31:25 PDT

The same change seems to have introduced flakiness in another test:
https://bugs.webkit.org/show_bug.cgi?id=186161

Comment 3 Mark Lam 2018-06-13 14:22:19 PDT

Landed a speculative fix in r232810: <http://trac.webkit.org/r232810>.

Please re-open or file a new bug if this test is still flaky.

Comment 4 Radar WebKit Bug Importer 2018-06-13 14:23:27 PDT

<rdar://problem/41101615>