1655422 - Remove exceptions added by allowMatchingRejectionsGlobally after each test

Status: RESOLVED FIXED

(Testing :: Mochitest, task, P3)

Description

[Julian Descottes [:jdescottes]]

The helper allowMatchingRejectionsGlobally allows to ignore promise rejections matching a given regexp:

  allowMatchingRejectionsGlobally(regExp) {
    this._globalRejectionIgnoreFns.push(rejection =>
      regExp.test(rejection.message)
    );
  },

https://searchfox.org/mozilla-central/rev/cf561cece0ca9aeaf0202e68699836d957d0c670/toolkit/modules/tests/modules/PromiseTestUtils.jsm#223

However, _globalRejectionIgnoreFns is never emptied. This means that if any test calls allowMatchingRejectionsGlobally, all the subsequent tests in the suite will be impacted. This means also some tests can fail in isolation, but succeed in a suite (example: Bug 1655411).

I don't know if we should modify the behavior, or just add an API to cleanup the array so that individual tests can cleanup the state on demand.

Comment 1

[Henrik Skupin [:whimboo][⌚️UTC+2]]

CC'ing Joel in case it's something we want to see fixed. It will also affect some Remote Agent mochitests soon, and a workaround would be to put these specific files into their own manifest file.

Comment 2

[Julian Descottes [:jdescottes]]

(In reply to Julian Descottes [:jdescottes] from comment #0)

I don't know if we should modify the behavior, or just add an API to cleanup the array so that individual tests can cleanup the state on demand.

I will do the latter, seems safer than impacting all the tests currently using this. Consumers which care about cleaning up the state can call the API in registerCleanupFunction.

Comment 3

[Julian Descottes [:jdescottes]]

Attachment: Bug 1655422 - Remove exceptions from allowMatchingRejectionsGlobally after each test

Comment 4

[Julian Descottes [:jdescottes]]

Attachment: Bug 1655422 - Remove optional keepAfterTest argument for allowMatchingRejectionsGlobally

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/8f89f8be9081
https://hg.mozilla.org/integration/autoland/rev/515a537cc817
Remove exceptions from allowMatchingRejectionsGlobally after each test r=Gijs

Comment 6

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/515a537cc817