Bug 196376

Summary: [ Mac WK2 iOS Sim Debug ] Layout Test storage/domstorage/localstorage/private-browsing-affects-storage.html is a flaky failure
Product: WebKit Reporter: Shawn Roberts <sroberts>
Component: Tools / TestsAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: achristensen, beidson, lforschler, webkit-bot-watchers-bugzilla, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   

Description Shawn Roberts 2019-03-28 15:25:11 PDT
The following layout test is flaky on Mac WK2 Release and Debug, iOS Simulator Debug

storage/domstorage/localstorage/private-browsing-affects-storage.html

Probable cause:

Unsure of regression point. When I test locally it fails after the first iteration run, then will pass on the retry. Test has been failing on the dashboard as long as the history goes, so I am unsure how long it's been a flaky failure.

Test was added in 2012, and has several changes over the years. most recent change was https://trac.webkit.org/changeset/216345/webkit

Flakiness Dashboard:

https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=storage%2Fdomstorage%2Flocalstorage%2Fprivate-browsing-affects-storage.html

Diff: 

--- /Volumes/Data/slave/mojave-release-tests-wk2/build/layout-test-results/storage/domstorage/localstorage/private-browsing-affects-storage-expected.txt
+++ /Volumes/Data/slave/mojave-release-tests-wk2/build/layout-test-results/storage/domstorage/localstorage/private-browsing-affects-storage-actual.txt
@@ -1,13 +1,13 @@
 ALERT: Persistent localStorage testItem is: Persistent item!
 ALERT: Start of private browsing test, testItem is: null
-ALERT: localStorage's length is: 0
+ALERT: localStorage's length is: 2
 ALERT: After set attempt, testItem is: FirstValue
 ALERT: After second set attempt, testItem is: ChangedValue
 ALERT: Opening window...
-ALERT: localStorage's length is: 1
+ALERT: localStorage's length is: 3
 ALERT: The item in new window starts out as: ChangedValue
 ALERT: The item in new window is now: NewWindowValue
-ALERT: Back in parent window, localStorage's length is: 1
+ALERT: Back in parent window, localStorage's length is: 3
 ALERT: Back in parent window, testItem is: ChangedValue
 ALERT: Final window, localStorage's length is: 1
 ALERT: Final window, item is: Persistent item!
Comment 1 Shawn Roberts 2019-03-28 15:26:07 PDT
Adding Brady Eidson to take a look since they created the test.
Comment 2 Radar WebKit Bug Importer 2019-03-28 15:27:06 PDT
<rdar://problem/49398647>
Comment 3 Shawn Roberts 2019-03-28 15:33:04 PDT
Marked flaky in https://trac.webkit.org/changeset/243628/webkit