1655411 - Test browser_inspector_fission_frame_navigation fails with Fission enabled

Status: RESOLVED FIXED

(DevTools :: Inspector, task, P3)

Description

[Julian Descottes [:jdescottes]]

Running mach test browser_inspector_fission_frame_navigation --enable-fission fails locally with the following error message:

A promise chain failed to handle a rejection: Connection closed, pending request to server0.conn1.windowGlobal19327352833/consoleActor3, type startListeners failed

The test doesn't seem to fail on try so far though. I am testing on macos, while we don't seem to be running Fission mochitests on this platform for now. Maybe this is OS specific, or maybe the race is really just specific to my machine.

Comment 1

[Julian Descottes [:jdescottes]]

Thanks Nicolas for helping with the investigation, it turns out that this test passes when running in a test suite because a previous test calls:

PromiseTestUtils.allowMatchingRejectionsGlobally(/Connection closed/);

https://searchfox.org/mozilla-central/rev/cf561cece0ca9aeaf0202e68699836d957d0c670/devtools/client/inspector/test/browser_inspector_breadcrumbs_visibility.js#13

And the list of promises "globally" allowed are not cleaned up at the end of a test. Which means that calling this API in any test potentially leaks to the whole test suite.

I understand that allowMatchingRejectionsGlobally should have a broader scope than expectUncaughtRejection. But I thought this was only about the number of failures: allowMatchingRejectionsGlobally allowed any number of failures, and expectUncaughtRejection only allowed one. We should probably reduce our usage of allowMatchingRejectionsGlobally as much as possible.

Comment 2

[Julian Descottes [:jdescottes]]

Attachment: Bug 1655411 - Emit processed-available-target after processing a new DevTools target

Comment 3

[Julian Descottes [:jdescottes]]

Attachment: Bug 1655411 - Wait for target-available-processed in browser_inspector_fission_frame_navigation test

Depends on D84969

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/1e917da8372e
Emit processed-available-target after processing a new DevTools target r=nchevobbe
https://hg.mozilla.org/integration/autoland/rev/b2f611f02ec0
Wait for target-available-processed in browser_inspector_fission_frame_navigation test r=nchevobbe

Comment 5

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/1e917da8372e
https://hg.mozilla.org/mozilla-central/rev/b2f611f02ec0