text: # -*- coding: utf-8 -*-
  ###########################################################################
  # Copyright (c), The AiiDA team. All rights reserved.                     #
  # This file is part of the AiiDA code.                                    #
  #                                                                         #
  # The code is hosted on GitHub at https://github.com/aiidateam/aiida-core #
  # For further information on the license, see the LICENSE.txt file        #
  # For further information please visit http://www.aiida.net               #
  ###########################################################################
  """Tests for the links utilities."""
  
  from aiida.backends.testbase import AiidaTestCase
  from aiida.common.links import validate_link_label
  
  
  class TestValidateLinkLabel(AiidaTestCase):
      """Tests for `validate_link_label` function."""
  
      def test_validate_link_label(self):
          """Test that illegal link labels will raise a `ValueError`."""
  
          illegal_link_labels = [
              '_leading_underscore',
              'trailing_underscore_',
              'non_numeric_%',
              'including.period',
              'disallowed👻unicodecharacters',
              'white space',
              'das-hes',
          ]
  
          for link_label in illegal_link_labels:
              with self.assertRaises(ValueError):
                  validate_link_label(link_label)
  