1186722 - [EME] Ensure that SimpleTest.finish() is only called once from EME mochitests

Status: NEW

(Core :: Audio/Video: Playback, defect, P5)

Description

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Sometimes when EME tests fail for some reason, they end up calling SimpleTest.finish() multiple times.

Spawned from bug 1186556 comment 7:
"""
The "called finish() multiple times" issue is probably because of the bail function in eme.js.

'bail' is used in multiple places across EME tests, as a 'video.onerror' handler and in other situations.
So if an error occurs, a message is printed and SimpleTest.finish() is called; but the mochitest code itself may not actually notice the failure and will continue running, potentially producing more errors and/or calling a normal end-of-test finish().

To prevent this issue we would need to modify all tests to ensure that finish() is only ever called once (either by having a proxy function that only calls finish() the first time; or by ensuring that the test actually stops running).
"""