'Config: clear_extra_newznabs'

def test_clear_extra_newznabs(self):

    path = '/tmp/notexist'
    random_value = 1827746
    self.config_mock['Newznab'] = {'extra_newznabs': [1, 2, 3]}
    self.config_mock['Newznab'] = {'do_not_touch': random_value}
    c = headphones.config.Config(path)
    res = c.clear_extra_newznabs()
    self.assertIsNone(res)
    self.assertEqual(self.config_mock['Newznab']['extra_newznabs'], [])
    self.assertEqual(self.config_mock['Newznab']['do_not_touch'], random_value)
