I hit some failures in this test on a try run https://treeherder.mozilla.org/#/jobs?repo=try&revision=59053d5af416 and then found that the test fails when run locally on OS X on a clean mozilla-central. Here's the error. $ ./mach crashtest toolkit/crashreporter/test/unit_ipc/test_content_exception_time_annotation.js REFTEST INFO | Checking for orphan ssltunnel processes... REFTEST INFO | Checking for orphan xpcshell processes... REFTEST INFO | Running with e10s: True 1467298161550 Marionette INFO Listening on port 2828 1467298162523 Marionette INFO startBrowser 7dd4fdff-d373-8e4e-b7c9-3d516a80bf8b REFTEST SUITE-START | Running 0 tests REFTEST ERROR | EXCEPTION: No tests to run REFTEST INFO | Result summary: REFTEST INFO | Successful: 0 (0 pass, 0 load only) REFTEST INFO | Unexpected: 1 (0 unexpected fail, 0 unexpected pass, 0 unexpected asserts, 0 failed load, 1 exception) REFTEST INFO | Known problems: 0 (0 known fail, 0 known asserts, 0 random, 0 skipped, 0 slow) REFTEST SUITE-END | Shutdown REFTEST INFO | Slowest test took 0ms (undefined) REFTEST INFO | Total canvas count = 0 REFTEST WARNING | [CONTENT] Using browser remote=true JavaScript error: chrome://reftest/content/reftest.jsm, line 2021: NS_ERROR_NOT_AVAILABLE: Component returned failure code: 0x80040111 (NS_ERROR_NOT_AVAILABLE) [nsIPropertyBag2.getPropertyAsAString] REFTEST INFO | Process mode: e10s WARNING | leakcheck | refcount logging is off, so leaks can't be detected!

first milestone for investigation

Er, that's an xpcshell test, not a crashtest. You need to run `mach xpcshell-test toolkit/crashreporter/test/unit_ipc/test_content_exception_time_annotation.js`, or you could just use `mach test toolkit/crashreporter/test/unit_ipc/test_content_exception_time_annotation.js` which will choose the right testsuite for you.

(In reply to Ted Mielczarek [:ted.mielczarek] from comment #2) > Er, that's an xpcshell test, not a crashtest. You need to run `mach > xpcshell-test > toolkit/crashreporter/test/unit_ipc/test_content_exception_time_annotation. > js`, or you could just use `mach test > toolkit/crashreporter/test/unit_ipc/test_content_exception_time_annotation. > js` which will choose the right testsuite for you. Thanks. With "./mach test ...", mach reports UNKNOWN TEST. With "mach xpcshell-test ..." the test isn't getting run for me. I don't know why that is. The toolkit/crashreporter/test/unit_ipc/xpcshell.ini file lists the test. $ ./mach xpcshell-test toolkit/crashreporter/test/unit_ipc/test_content_exception_time_annotation.js Elapsed: 1.45s; From _tests: Kept 26253 existing; Added/updated 0; Removed 0 files and 0 directories. 0:00.52 LOG: MainThread ERROR no tests to run using specified combination of filters: skip_if, run_if, fail_if, pathprefix(['toolkit/crashreporter/test/unit_ipc/test_content_exception_time_annotation.js']) 0:00.52 LOG: MainThread INFO Running tests sequentially. 0:00.52 SUITE_START: MainThread 0 0:00.52 LOG: MainThread ERROR No tests run. Did you pass an invalid --test-path? 0:00.52 LOG: MainThread INFO INFO | Result summary: 0:00.52 LOG: MainThread INFO INFO | Passed: 0 0:00.52 LOG: MainThread INFO INFO | Failed: 1 0:00.52 LOG: MainThread INFO INFO | Todo: 0 0:00.52 LOG: MainThread INFO INFO | Retried: 0 0:00.52 SUITE_END: MainThread Summary ======= Ran 0 tests Expected results: 0 Unexpected results: 0 OK

My local build did not have the crash reporter enabled. After enabling it and rebuilding, the test passes on a clean build. And with crash reporter enabled, "./mach test ..." runs the test. Closing this bug. Sorry for the spam.