def test_dont_add_file_extension_again(self):
     """Extension is not added to a filename if already present."""
     fname = 'filename.{0}'.format(self.fextension)
     assert tasks.add_file_extension(fname) == fname
 def test_add_file_extension(self):
     """Extension is added to a filename when not present."""
     fname = 'filename'
     fname_expected = '{0}.{1}'.format(fname, self.fextension)
     assert tasks.add_file_extension(fname) == fname_expected