Treeherder link: https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&selectedJob=284056575&resultStatus=testfailed%2Cbusted%2Cexception

Log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=284056575&repo=mozilla-central&lineNumber=2727

[task 2020-01-08T18:26:17.461Z] 18:26:17 INFO - TEST-START | toolkit/components/telemetry/tests/unit/test_PingSender.js
[task 2020-01-08T18:26:21.970Z] 18:26:21 WARNING - TEST-UNEXPECTED-FAIL | toolkit/components/telemetry/tests/unit/test_PingSender.js | xpcshell return code: -11
[task 2020-01-08T18:26:21.971Z] 18:26:21 INFO - TEST-INFO took 4510ms
[task 2020-01-08T18:26:21.971Z] 18:26:21 INFO - >>>>>>>
[task 2020-01-08T18:26:21.972Z] 18:26:21 INFO - PID 19380 | [CodeCoverage] Setting handlers for process 19380.
[task 2020-01-08T18:26:21.972Z] 18:26:21 INFO - (xpcshell/head.js) | test MAIN run_test pending (1)
[task 2020-01-08T18:26:21.972Z] 18:26:21 INFO - (xpcshell/head.js) | test run_next_test 0 pending (2)
[task 2020-01-08T18:26:21.973Z] 18:26:21 INFO - (xpcshell/head.js) | test MAIN run_test finished (2)
[task 2020-01-08T18:26:21.973Z] 18:26:21 INFO - running event loop
[task 2020-01-08T18:26:21.973Z] 18:26:21 INFO - toolkit/components/telemetry/tests/unit/test_PingSender.js | Starting setup
[task 2020-01-08T18:26:21.973Z] 18:26:21 INFO - (xpcshell/head.js) | test setup pending (2)
[task 2020-01-08T18:26:21.973Z] 18:26:21 INFO - (xpcshell/head.js) | test run_next_test 0 finished (2)
[task 2020-01-08T18:26:21.975Z] 18:26:21 INFO - (xpcshell/head.js) | test run_next_test 1 pending (2)
[task 2020-01-08T18:26:21.975Z] 18:26:21 INFO - (xpcshell/head.js) | test setup finished (2)
[task 2020-01-08T18:26:21.975Z] 18:26:21 INFO - toolkit/components/telemetry/tests/unit/test_PingSender.js | Starting test_pingSender
[task 2020-01-08T18:26:21.977Z] 18:26:21 INFO - (xpcshell/head.js) | test test_pingSender pending (2)
[task 2020-01-08T18:26:21.977Z] 18:26:21 INFO - (xpcshell/head.js) | test run_next_test 1 finished (2)
[task 2020-01-08T18:26:21.978Z] 18:26:21 INFO - "CONSOLE_MESSAGE: (info) 1578507978504 Toolkit.Telemetry TRACE TelemetryStorage::savePingToFile - path: /tmp/xpc-profile-qCdMxj/saved-telemetry-pings/9b85fc70-5e99-4a49-abdd-146e03fef13c"
[task 2020-01-08T18:26:21.979Z] 18:26:21 INFO - TEST-PASS | toolkit/components/telemetry/tests/unit/test_PingSender.js | test_pingSender - [test_pingSender : 92] The pending ping must not be deleted if we fail to send using the PingSender - true == true
[task 2020-01-08T18:26:21.979Z] 18:26:21 INFO - PID 19380 | JavaScript strict warning: /builds/worker/workspace/build/tests/xpcshell/tests/toolkit/components/telemetry/tests/unit/head.js, line 211: ReferenceError: reference to undefined property "clientId"
[task 2020-01-08T18:26:21.980Z] 18:26:21 INFO - TEST-PASS | toolkit/components/telemetry/tests/unit/test_PingSender.js | test_pingSender - [test_pingSender : 119] Known clientId shouldn't appear in a "test-pingsender-type" ping on the server. - "c0ffeec0-ffee-c0ff-eec0-ffeec0ffeec0" != "undefined"

The priority flag is not set for this bug.
:ekyle, could you have a look please?

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The priority flag is not set for this bug.
:chutten, could you have a look please?

For more information, please visit auto_nag documentation.

Well that's interesting. This failure log suggests that the PingServer is receiving a ping without a clientId. Which is a valid ping, so the test shouldn't fail.

Looks like maybe the test for the c0ffee client id isn't handling non-client-id-having pings properly. Should be a quick fix.

Depends on D60993

https://hg.mozilla.org/mozilla-central/rev/a6d0eb170579
https://hg.mozilla.org/mozilla-central/rev/57131ac43813