Last week I spent over an hour trying to debug a hang in a test that would not have taken very long at all had xpcshell either been throwing an error or at the very least logging when some code does Components.utils.reportError. I'm leaning toward error being the right call, but at this point, we might have tests that depend on that not failing, so logging may be the only option. See https://hg.mozilla.org/mozilla-central/annotate/6105fb36f613/toolkit/components/places/tests/unit/test_preventive_maintenance_console.js#l17 for an example on how to do this (hell, I'll even write this patch if someone makes the decision on which way to go).
If it doesn't fail any tests, then make it error. If it does, then just make it log for now.
Created attachment 551960 [details] [diff] [review] Write all console service messages to output, v1 In the course of filing bug 677779, I created a simple patch to write all console service messages to the output of the xpcshell test harness. The patch doesn't conditionally log (as desired from comment #1), so I'm not submitting it for review. But, if somebody wants to use it as the base for the final patch, be my guest! Or, if we just want to ignore comment #1, I suppose this is ready for review.
Comment on attachment 565412 [details] [diff] [review] Write console service messages to output, v2 Cancelling review due to Try failures.
(In reply to Gregory Szorc [:gps] from comment #4) > Comment on attachment 565412 [details] [diff] [review] > Cancelling review due to Try failures. Can you remember what kinds of errors you saw on try? This cost me some time today too - maybe a lighter approach with less impact on a "normal" run is to have the harness buffer output from a test and only dump it on test failure?