def cross_cube_self_test():
    """
  This is the non-regression test of cross_cube.
  Look at the Tk window to check errors.
  """
    r_tests = [['simplest test', ''], ['extra cut',
        '--cross_cube_extra_cut_thickness 1.0'], ['extra cut negative',
        '--cross_cube_extra_cut_thickness -2.0'], ['one crest',
        '--face_A1_crest'], ['two crests',
        '--face_A1_crest --face_B1_crest'], ['double crests on A',
        '--face_A1_crest --face_A2_crest'], ['outputfile',
        '--output_file_basename test_output/cross_cube_self_test.dxf'], [
        'last test', '']]
    return r_tests
