'A pair of FilePaths are returned for device_file and backing_file.'

def test_parse_one_line(self):

    input_text = '\n'.join(['/dev/loop0:    []:    (/tmp/rjw)', ''])
    self.assertEqual([(FilePath('/dev/loop0'), FilePath('/tmp/rjw'))], _losetup_list_parse(input_text))
