test_drop_privileges AssertionError groups mismatch

[Corey Bryant]

This test is failing in Ubuntu builds on Artful. However I think it generally just gets lucky when it is successful.

======================================================================
FAIL: test_drop_privileges (test.unit.common.test_utils.TestUtils)
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Traceback (most recent call last):
  File "/<<PKGBUILDDIR>>/test/unit/common/test_utils.py", line 2151, in test_drop_privileges
    self.assertEqual(set(groups), set(os.getgroups()))
AssertionError: Items in the second set but not the first:
110
    """Fail immediately, with the given message."""
>> raise self.failureException('Items in the second set but not the first:\n110')

It seems that setgroups() is mocked out. Part of what drop_privileges() does is:

    groups = [g.gr_gid for g in grp.getgrall() if user in g.gr_mem]
    os.setgroups(groups)

The failing part of test_drop_privileges() is:

    groups = [g.gr_gid for g in grp.getgrall() if user in g.gr_mem]
    groups.append(pwd.getpwnam(user).pw_gid)
    self.assertEqual(set(groups), set(os.getgroups()))

The test is trying to assert that os.getgroups() was set in drop_privileges. However os.getgroups() can't change since os.setgroups() is mocked out, and os.getgroups() isn't mocked out.