Closed Bug 1274002 Opened 4 years ago Closed 4 years ago

Mochitest chrome is run with e10s enabled by default with mach


(Testing :: Mochitest, defect)

Not set


(e10s+, firefox49 fixed)

Tracking Status
e10s + ---
firefox49 --- fixed


(Reporter: ahal, Assigned: ahal)


(Blocks 1 open bug)



(1 file)

When running with mach, mochitest-chrome wrongfully has e10s enabled. This is because the mochitest mach command dynamically sets the flavor after the fact. I.e doesn't get set until after this check occurs:

The fix should be to move that check later on in the harness. This doesn't affect automation, just running locally.
Blocks: 1243083
Comment on attachment 8754004 [details]
MozReview Request: Bug 1274002 - Disable e10s when running mochitest-chrome locally with mach, r?jmaher

Attachment #8754004 - Flags: review?(jmaher) → review+
Blocks: e10s-tests
tracking-e10s: --- → +
Closed: 4 years ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla49
Given we ship e10s now, is there any reason to run these tests with e10s disabled (on desktop at least)?  This bit me in bug 1416872.  I've also found other webextension mochitest-chrome tests that are not quite working under e10s and am looking at transitioning them somehow in bug 1417639.
Flags: needinfo?(jmaher)
I had disabled all non-e10s tests but then received pushback for a few valid cases:
1) gecko runs on android which is non-e10s
2) firefox users can run gecko in non-e10s for legacy addons and other a11y/media reasons

Right now these are enabled as windows7-debug only, if there are specific tests to turn off, I think that is a valid ask- I imagine in Q2 we could discuss turning all non-e10s off.  As for mochitest-chrome, I don't think we run those specific tests in e10s mode, so on all platforms these only run in non-e10s.  You can see all tests which are run as non-e10s only:
Flags: needinfo?(jmaher)
(In reply to Joel Maher ( :jmaher) (UTC-5) from comment #6)
> As for mochitest-chrome, I don't think we
> run those specific tests in e10s mode, so on all platforms these only run in
> non-e10s.

The thing I particularly care about is I want these particular tests[1] to run with e10s on desktop.  I started to move them to mochitest-browser-chrome before I was reminded they would no longer run under android.  They make use of the fact they are in chrome, but they are webextension tests which should IMO always run with e10s.  Porting them to mochitest-plain is a chunk of effort as well, so I was wondering why we shouldn't just enable e10s for mochitest-chrome on desktop (or at least by some option).  The patch in this bug seems to prevent any option to enable e10s for mochitest-chrome.

[1] see
if you submit a patch with try results, I am happy to review it.  My understanding is mochitest-chrome doesn't work in e10s mode.
Component: Mochitest Chrome → Mochitest
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