Fake attrs on _Namespace change breaks Neutron tests

[Davanum Srinivas (DIMS)]

Running Neutron with oslo.config from master breaks py27 test

2016-02-02 14:14:53.045 | neutron.tests.unit.db.test_migration.TestCli.test_downgrade_fails
2016-02-02 14:14:53.045 | -----------------------------------------------------------------
2016-02-02 14:14:53.045 |
2016-02-02 14:14:53.045 | Captured traceback:
2016-02-02 14:14:53.045 | ~~~~~~~~~~~~~~~~~~~
2016-02-02 14:14:53.045 | Traceback (most recent call last):
2016-02-02 14:14:53.045 | File "neutron/tests/unit/db/test_migration.py", line 336, in test_downgrade_fails
2016-02-02 14:14:53.045 | self.assert_command_fails(['prog', 'downgrade', '--sql', 'juno'])
2016-02-02 14:14:53.045 | File "neutron/tests/unit/db/test_migration.py", line 333, in assert_command_fails
2016-02-02 14:14:53.045 | self.assertRaises(SystemExit, cli.main)
2016-02-02 14:14:53.046 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/local/lib/python2.7/site-packages/testtools/testcase.py", line 434, in assertRaises
2016-02-02 14:14:53.046 | self.assertThat(our_callable, matcher)
2016-02-02 14:14:53.046 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/local/lib/python2.7/site-packages/testtools/testcase.py", line 445, in assertThat
2016-02-02 14:14:53.046 | mismatch_error = self._matchHelper(matchee, matcher, message, verbose)
2016-02-02 14:14:53.046 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/local/lib/python2.7/site-packages/testtools/testcase.py", line 495, in _matchHelper
2016-02-02 14:14:53.046 | mismatch = matcher.match(matchee)
2016-02-02 14:14:53.046 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/local/lib/python2.7/site-packages/testtools/matchers/_exception.py", line 108, in match
2016-02-02 14:14:53.046 | mismatch = self.exception_matcher.match(exc_info)
2016-02-02 14:14:53.046 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/local/lib/python2.7/site-packages/testtools/matchers/_higherorder.py", line 62, in match
2016-02-02 14:14:53.046 | mismatch = matcher.match(matchee)
2016-02-02 14:14:53.046 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/local/lib/python2.7/site-packages/testtools/testcase.py", line 426, in match
2016-02-02 14:14:53.047 | reraise(*matchee)
2016-02-02 14:14:53.047 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/local/lib/python2.7/site-packages/testtools/matchers/_exception.py", line 101, in match
2016-02-02 14:14:53.047 | result = matchee()
2016-02-02 14:14:53.047 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/local/lib/python2.7/site-packages/testtools/testcase.py", line 982, in __call__
2016-02-02 14:14:53.047 | return self._callable_object(*self._args, **self._kwargs)
2016-02-02 14:14:53.047 | File "neutron/db/migration/cli.py", line 739, in main
2016-02-02 14:14:53.047 | CONF(project='neutron')
2016-02-02 14:14:53.047 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/src/oslo.config/oslo_config/cfg.py", line 2166, in __call__
2016-02-02 14:14:53.047 | else sys.argv[1:])
2016-02-02 14:14:53.047 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/src/oslo.config/oslo_config/cfg.py", line 2750, in _parse_cli_opts
2016-02-02 14:14:53.047 | return self._parse_config_files()
2016-02-02 14:14:53.048 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/src/oslo.config/oslo_config/cfg.py", line 2767, in _parse_config_files
2016-02-02 14:14:53.048 | self._oparser.parse_args(self._args, namespace)
2016-02-02 14:14:53.048 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/src/oslo.config/oslo_config/cfg.py", line 2016, in parse_args
2016-02-02 14:14:53.048 | return super(_CachedArgumentParser, self).parse_args(args, namespace)
2016-02-02 14:14:53.048 | File "/usr/lib/python2.7/argparse.py", line 1690, in parse_args
2016-02-02 14:14:53.048 | args, argv = self.parse_known_args(args, namespace)
2016-02-02 14:14:53.048 | File "/usr/lib/python2.7/argparse.py", line 1725, in parse_known_args
2016-02-02 14:14:53.048 | delattr(namespace, _UNRECOGNIZED_ARGS_ATTR)
2016-02-02 14:14:53.048 | File "/home/jenkins/workspace/gate-neutron-python27-constraints/.tox/py27-constraints/src/oslo.config/oslo_config/cfg.py", line 1787, in __delattr__
2016-02-02 14:14:53.048 | "'_Namespace' object has no attribute '%s'" % name)
2016-02-02 14:14:53.048 | AttributeError: '_Namespace' object has no attribute '_unrecognized_args'

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/275307

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/275307
Committed: https://git.openstack.org/cgit/openstack/oslo.config/commit/?id=068784afab28631b2a8fcd5dbc55a777508f63b6
Submitter: Jenkins
Branch: master

commit 068784afab28631b2a8fcd5dbc55a777508f63b6
Author: Alexis Lee <email address hidden>
Date: Tue Feb 2 16:19:20 2016 +0000

    Fix unrecognized subparser args

    Someone thought a transient attr would be a clever way to smuggle data
    from a _SubParsersAction up to the main ArgumentsParser. Unfortunately
    they use a really weird way to set the attr:

        vars(namespace).setdefault(_UNRECOGNIZED_ARGS_ATTR, [])

    This bypasses __setattr__ so when they try to delattr later,
    __delattr__ can't find it and bombs. Even though the delattr is
    protected by a hasattr, because hasattr uses getattr which checks the
    private object dict first before calling __getattr__.

    Handle this by falling back to super in __getattr__ and __delattr__.

    Change-Id: Id89a0c00fd32b6580d891ccf69d58fa17f11ec49
    Closes-Bug: #1540959

[Davanum Srinivas (DIMS) (dims-v)]

This issue was fixed in the openstack/oslo.config 3.5.0 release.