py35 unit tests are hugely failing

[Sylvain Bauza]

We have a long list of Nova unit tests that fail for the py35 job with this pattern :

ft2.9: nova.tests.unit.api.openstack.compute.test_create_backup.CreateBackupTestsV21.test_create_backup_raises_conflict_on_invalid_state_StringException: Empty attachments:
  pythonlogging:''
  stderr
  stdout

traceback-1: {{{
Traceback (most recent call last):
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/fixtures/fixture.py", line 125, in cleanUp
    return self._cleanups(raise_errors=raise_first)
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/fixtures/callmany.py", line 89, in __call__
    reraise(error[0], error[1], error[2])
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/testtools/_compat3x.py", line 16, in reraise
    raise exc_obj.with_traceback(exc_tb)
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/fixtures/callmany.py", line 83, in __call__
    cleanup(*args, **kwargs)
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/mox3/mox.py", line 289, in VerifyAll
    mock_obj._Verify()
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/mox3/mox.py", line 543, in _Verify
    raise ExpectedMethodCallsError(self._expected_calls_queue)
mox3.mox.ExpectedMethodCallsError: Verify: Expected methods never called:
  0. function.__call__(<nova.tests.unit.api.openstack.fakes.FakeRequestContext object at 0x7f481db10668>, {}) -> None
}}}

Traceback (most recent call last):
  File "/home/jenkins/workspace/gate-nova-python35-db/nova/tests/unit/api/openstack/compute/test_create_backup.py", line 281, in test_create_backup_raises_conflict_on_invalid_state
    exception_arg='createBackup')
  File "/home/jenkins/workspace/gate-nova-python35-db/nova/tests/unit/api/openstack/compute/admin_only_action_common.py", line 123, in _test_invalid_state
    instance = self._stub_instance_get()
  File "/home/jenkins/workspace/gate-nova-python35-db/nova/tests/unit/api/openstack/compute/admin_only_action_common.py", line 40, in _stub_instance_get
    self.context, uuid, expected_attrs=None).AndReturn(instance)
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/mox3/mox.py", line 814, in __call__
    return mock_method(*params, **named_params)
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/mox3/mox.py", line 1152, in __call__
    self._checker.Check(params, named_params)
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/mox3/mox.py", line 1067, in Check
    self._RecordArgumentGiven(arg_name, arg_status)
  File "/home/jenkins/workspace/gate-nova-python35-db/.tox/py35/lib/python3.5/site-packages/mox3/mox.py", line 994, in _RecordArgumentGiven
    raise AttributeError('%s provided more than once' % (arg_name,))
AttributeError: expected_attrs provided more than once

eg. http://logs.openstack.org/34/418134/7/check/gate-nova-python35-db/578aaff/testr_results.html.gz

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/mox3 0.20.0 release.

[Matt Riedemann (mriedem)]

Will be fixed once this is through: https://review.openstack.org/#/c/422709/

[Matt Riedemann (mriedem)]

The mox3 revert is merged, released and in upper-constraints now so we're good again.