def it_can_calculate_relative_ref_value(self):
     cases = (
         ('/', '/ppt/presentation.xml', 'ppt/presentation.xml'),
         ('/ppt', '/ppt/slideMasters/slideMaster1.xml',
          'slideMasters/slideMaster1.xml'),
         ('/ppt/slides', '/ppt/slideLayouts/slideLayout1.xml',
          '../slideLayouts/slideLayout1.xml'),
     )
     for baseURI, uri_str, expected_relative_ref in cases:
         pack_uri = PackURI(uri_str)
         assert pack_uri.relative_ref(baseURI) == expected_relative_ref
 def it_can_calculate_relative_ref_value(self):
     cases = (
         ("/", "/ppt/presentation.xml", "ppt/presentation.xml"),
         (
             "/ppt",
             "/ppt/slideMasters/slideMaster1.xml",
             "slideMasters/slideMaster1.xml",
         ),
         (
             "/ppt/slides",
             "/ppt/slideLayouts/slideLayout1.xml",
             "../slideLayouts/slideLayout1.xml",
         ),
     )
     for baseURI, uri_str, expected_relative_ref in cases:
         pack_uri = PackURI(uri_str)
         assert pack_uri.relative_ref(baseURI) == expected_relative_ref