Merge lp:~abentley/launchpad/better-find-missing-ready-error into lp:launchpad

[Aaron Bentley]

Add detailed failure output to test_find_missing_ready.

= Summary =
Add detailed failure output to test_find_missing_ready, so that we can diagnose the cause of its intermittent failures.

== Proposed fix ==
Because we cannot reproduce the bug outside of buildbot, leave test_find_missing_ready active, but add more diagnostics so that we can understand the cause of the problem.

== Pre-implementation notes ==
Discussed with deryck

== LOC Rationale ==
I have a LOC credit of 1928

== Implementation details ==
None

== Tests ==
bin/test -t test_find_missing_ready

== Demo and Q/A ==
None

= Launchpad lint =

Checking for conflicts and issues in changed files.

Linting changed files:
  lib/lp/services/job/tests/test_celeryjob.py

[Francesco Banconi (frankban)]

Looks good, thank you.
As said on IRC, please add an XXX that points to the bug we are trying to diagnose.

review: Approve (code*)

[Raphaël Badin (rvb)]

Looks good, have fun with the debugging ;).

fwiw, we use fixture's self.addDetail a lot in MAAS, very useful to debug intermittent failures.

review: Approve

=== modified file 'lib/lp/services/job/tests/test_celeryjob.py'
--- lib/lp/services/job/tests/test_celeryjob.py	2012-07-30 19:07:47 +0000
+++ lib/lp/services/job/tests/test_celeryjob.py	2012-08-01 15:12:09 +0000
@@ -62,7 +62,15 @@
         job.runViaCelery()
         self.assertQueueSize(self.CeleryRunJob.app,
                              [BranchScanJob.task_queue], 1)
-        self.assertEqual([], self.find_missing_ready(BranchScanJob))
+        #self.assertEqual([], self.find_missing_ready(BranchScanJob))
+        # XXX AaronBentley: 2012-08-01 bug=1031018: Extra diagnostic info to
+        # help diagnose this hard-to-reproduce failure.
+        if self.find_missing_ready(BranchScanJob) != []:
+            from lazr.jobrunner.celerytask import list_queued
+            contents = list_queued(
+                self.CeleryRunJob.app, [BranchScanJob.task_queue])
+            self.fail('queue: %r, job.id: %d, job.job_id: %d' %
+                      (contents, job.id, job.job_id))
         drain_celery_queues()
         self.assertQueueSize(self.CeleryRunJob.app,
                              [BranchScanJob.task_queue], 0)