def test_serialise(self, GradientFill): gf = GradientFill(degree=90, left=1, right=2, top=3, bottom=4, stop=[BLACK, WHITE]) xml = tostring(gf.to_tree()) expected = """ <fill> <gradientFill bottom="4" degree="90" left="1" right="2" top="3" type="linear"> <stop position="0"> <color rgb="00000000"></color> </stop> <stop position="1"> <color rgb="00FFFFFF"></color> </stop> </gradientFill> </fill> """ diff = compare_xml(xml, expected) assert diff is None, diff