def run_test(self, ignored=None):
     positions = dynamic_positions
     if ignored:
         positions = [pos for pos in positions
                      if not pos[2].startswith(ignored)]
         parameters = ['--ignore', ','.join(ignored)]
     else:
         parameters = []
     self.messages = []
     flake8_string_format.main(parameters + [self.tmp_file])
     self.compare_results(self.iterator(), positions)
 def test_main(self):
     self.assertIs(flake8_string_format.main([]), False)
     self.assertEqual(self.messages,
                      ['argparse is required for the standalone version.'])