'setup_databases() doesn\'t fail with dummy database backend.'

def test_setup_databases(self):

    tested_connections = db.ConnectionHandler({})
    with mock.patch('django.test.utils.connections', new=tested_connections):
        runner_instance = DiscoverRunner(verbosity=0)
        old_config = runner_instance.setup_databases()
        runner_instance.teardown_databases(old_config)
