https://tbpl.mozilla.org/php/getParsedLog.php?id=33771907&tree=Mozilla-Inbound#error0 slave: tst-linux64-ec2-018 16:27:59 INFO - 4592 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | 2 === 2: Should resolve to 2. 16:27:59 INFO - 4593 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | true: Should cast to a Promise. 16:27:59 INFO - 4594 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | [object Promise] === [object Promise]: Should return original Promise. 16:27:59 INFO - 4595 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | true: Should return a Promise. 16:27:59 INFO - 4596 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | true: Should return a Promise. 16:27:59 INFO - 4597 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | true === true: First value should win. 16:27:59 INFO - 4598 ERROR TEST-UNEXPECTED-FAIL | /tests/dom/workers/test/test_promise.html | 50 === 20: Fastest timeout should win. 16:27:59 INFO - 4599 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | true: Should be rejected 16:27:59 INFO - 4600 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | true: Should reject with Error. 16:27:59 INFO - 4601 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | true: Message should match. 16:27:59 INFO - 4602 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | true: Should be rejected 16:27:59 INFO - 4603 INFO TEST-PASS | /tests/dom/workers/test/test_promise.html | true: Should reject with ReferenceError for function nonExistent().

Nikhil, any idea what might be going on here? :)

Guess I can't rely on setTimeout() ordering. Will fix this soon.

Yes, using setTimeout in tests is almost always a bad idea :) https://developer.mozilla.org/en-US/docs/Mozilla/QA/Avoiding_intermittent_oranges

Comment on attachment 8441579 [details] [diff] [review] Fix intermittent oranges on promise worker tests. Ah, yes. You can't "rely on timeout ordering" because what can happen is that after the timeoutPromise(50) call you lose the timeslice for 40ms, so the timeoutPromise(20) ends up scheduled for T+60 while the timeoutPromise(50) is scheduled for T+50. >+ new Promise(function() {}), What resolves this promise, exactly? Also, don't you need a similar change for test_promise_utils.html?

(In reply to Boris Zbarsky [:bz] from comment #204) > Comment on attachment 8441579 [details] [diff] [review] > Fix intermittent oranges on promise worker tests. > > Ah, yes. You can't "rely on timeout ordering" because what can happen is > that after the timeoutPromise(50) call you lose the timeslice for 40ms, so > the timeoutPromise(20) ends up scheduled for T+60 while the > timeoutPromise(50) is scheduled for T+50. > > >+ new Promise(function() {}), > > What resolves this promise, exactly? Nothing, it is unresolved. > > Also, don't you need a similar change for test_promise_utils.html? Good point.

Updated main thread tests.

> Nothing, it is unresolved. Ah, I guess for race() that doesn't matter, right.

Comment on attachment 8441613 [details] [diff] [review] Fix intermittent oranges on promise tests. r=me

remote: https://hg.mozilla.org/integration/mozilla-inbound/rev/0a3b00521c3b

Backed out in https://hg.mozilla.org/integration/mozilla-inbound/rev/d7a66cb08140 for making test_promise.html practically permafail: https://tbpl.mozilla.org/php/getParsedLog.php?id=41912041&tree=Mozilla-Inbound