unittest setUp fails to cleanup resources (from tearDown) if setUp fails - knockon effect looks like testresources issue as testresources does not use addCleanup

[Björn Tillenius]

If I inherit from ResourcedTestCase and something goes wrong in my setUp, the resources won't get cleaned up, since tearDown() won't be called. This can cause the next tests to fail, since the environment isn't cleaned (for example the db might not have been reset, thus containing unexpected data)

From IRC:

< BjornT> lifeless: no, the issue is that when something goes wrong in
          setUp(), TestCase.tearDown() doesn't get called, which makes
          all following tests fail with a db error (since it doesn't
          start with a clean db)
< lifeless> ah
< lifeless> cleanups addressed this, by running always (IIRC)
< lifeless> I'm not sure if we fixed tearDown in that matter for
            testtools.
< lifeless> we might want to do a cleanup based variant of
            resourcedtestcase

[Robert Collins (lifeless)]

For clarity, tearDown not running isn't due to anything in
testresources, its the test framework (unittest/unittest2/testtools)
doing that.

This however is obviously affecting whether resourceteardown is occuring.

[Robert Collins (lifeless)]

Ok, so - this is basically no different with testresources than with any by-hand use of shared state across tests. Use of addCleanup rather than depending on tearDown running would fix it.

-> We should have the TestResources basic glue use addCleanup when possible.

[Mariusz Jamro (mariusz-jamro)]

The same happens if the test is skipped by raising SkipTest in setUp

class SkipTestCase(testresources.ResourcedTestCase):
    resources = [TEST_RESOURCE]

    def setUp(self):
        raise SkipTest("Skip")

    def test(self):
        pass

The TEST_RESOUCE will be made but won't be cleared.