Bug 170772 - Getting snapshot of WKWebView fails ImageDiff tests
Summary: Getting snapshot of WKWebView fails ImageDiff tests
Status: NEW
Alias: None
Product: WebKit
Classification: Unclassified
Component: WebKit API (show other bugs)
Version: Other
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Jonathan Bedard
Depends on:
Reported: 2017-04-12 09:05 PDT by Jonathan Bedard
Modified: 2017-06-12 10:28 PDT (History)
4 users (show)

See Also:

Test results when using snapshot API for ImageDiff (14.52 MB, application/zip)
2017-04-12 09:06 PDT, Jonathan Bedard
no flags Details
Patch (3.42 KB, patch)
2017-06-09 09:57 PDT, Jonathan Bedard
buildbot: commit-queue-
Details | Formatted Diff | Diff
Archive of layout-test-results from ews125 for ios-simulator-wk2 (1.57 MB, application/zip)
2017-06-09 11:23 PDT, Build Bot
no flags Details

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Description Jonathan Bedard 2017-04-12 09:05:01 PDT
When testing, WebKit will frequently take a snapshot of the current WKWebView and compare it to some expected value.  While developing this functionality for on-device testing (https://bugs.webkit.org/show_bug.cgi?id=169421), it was suggested that the snapshotting API should be used.  I have attached test results from this run.  For 6 of the tests, the snapshotting API does not give the expected result.  Looking at the results, expected results and the screen of the device while running the tests, this seems to be a bug in the snapshotting API.  I think compositing/regions/position-layers-inside-region-overflow-hidden.html demonstrates this most clearly.
Comment 1 Jonathan Bedard 2017-04-12 09:06:09 PDT
Created attachment 306912 [details]
Test results when using snapshot API for ImageDiff
Comment 2 Jonathan Bedard 2017-06-03 08:16:04 PDT
Originally there were 5 of these failures.  Now, I only see compositing/geometry/clipped-out-perspective.html and compositing/hidpi-subpixel-transform-origin.html.
Comment 3 Jonathan Bedard 2017-06-09 09:57:03 PDT
Created attachment 312447 [details]
Comment 4 Jonathan Bedard 2017-06-09 09:58:11 PDT
Local on-device testing has indicated that these tests no longer fail. I'd like to see if EWS agrees with this for iOS-Simulators.
Comment 5 Build Bot 2017-06-09 11:23:55 PDT
Comment on attachment 312447 [details]

Attachment 312447 [details] did not pass ios-sim-ews (ios-simulator-wk2):
Output: http://webkit-queues.webkit.org/results/3901268

New failing tests:
Comment 6 Build Bot 2017-06-09 11:23:56 PDT
Created attachment 312462 [details]
Archive of layout-test-results from ews125 for ios-simulator-wk2

The attached test failures were seen while running run-webkit-tests on the ios-sim-ews.
Bot: ews125  Port: ios-simulator-wk2  Platform: Mac OS X 10.12.5
Comment 7 Jonathan Bedard 2017-06-12 10:28:59 PDT
It appears that these tests only fail on Simulator.  They succeed on device.