Bug 181008 – Layout Test http/tests/images/image-supports-video.html is flaky

• Component: Media
• Status: REOPENED

[Matt Lewis]

The following layout test is flaky on macOS WK!

http/tests/images/image-supports-video.html

Probable cause:

Test was flaky from the initial commit in https://trac.webkit.org/changeset/225472/webkit

Flakiness Dashboard:

https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=http%2Ftests%2Fimages%2Fimage-supports-video.html


https://build.webkit.org/results/Apple%20Sierra%20Debug%20WK1%20(Tests)/r226129%20(5383)/results.html
https://build.webkit.org/builders/Apple%20Sierra%20Debug%20WK1%20(Tests)/builds/5383

diff:

--- /Volumes/Data/slave/sierra-debug-tests-wk1/build/layout-test-results/http/tests/images/image-supports-video-expected.txt
+++ /Volumes/Data/slave/sierra-debug-tests-wk1/build/layout-test-results/http/tests/images/image-supports-video-actual.txt
@@ -1,2 +1,2 @@
   
-PASS: video source selected.
+FAIL: <img> threw error.

[Radar WebKit Bug Importer]

<rdar://problem/36143943>

[Matt Lewis]

Marked as flaky on macOS WK1: https://trac.webkit.org/changeset/226159/webkit

[Jer Noble]

From the access_log.txt on the failing test, I see a request for the initial image URL (meaning the test passed), but not for the redirected URL.ng

e.g., on a passing run:

127.0.0.1 - - [20/Dec/2017:12:17:29 -0800] "GET /resources/redirect-to-video-if-accepted.php?video=test.mp4 HTTP/1.1" 301 - 1356
127.0.0.1 - - [20/Dec/2017:12:17:29 -0800] "GET /resources/test.mp4 HTTP/1.1" 200 192844 1862

and on a failing run:

127.0.0.1 - - [09/Dec/2017:13:51:01 -0800] "GET /resources/redirect-to-video-if-accepted.php?video=test.mp4 HTTP/1.1" 301 - 1163

(with no matching request for "test.mp4".)

Could we be hitting a weird memory cache corner case?

[Jer Noble]

This may be just another instance of bug #77538, which is worked around by adding a cache-control error.

[Jer Noble]

Created attachment 331599 [details]
Patch

[WebKit Commit Bot]

Comment on attachment 331599 [details]
Patch

Clearing flags on attachment: 331599

Committed r227137: <https://trac.webkit.org/changeset/227137>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Ryan Haddad]

*** Bug 181862 has been marked as a duplicate of this bug. ***

[Ryan Haddad]

This test is still flaky after https://trac.webkit.org/changeset/227137

[Jer Noble]

(In reply to Ryan Haddad from comment #9)
> This test is still flaky after https://trac.webkit.org/changeset/227137

Crud.