def test_xml_filters_round_trip():
 plot = Bar()
 plot.add('A', [60, 75, 80, 78, 83, 90])
 plot.add('B', [92, 87, 81, 73, 68, 55])
 before = plot.render()
 plot.add_xml_filter((lambda T: T))
 after = plot.render()
 assert (before == after)

def test_xml_filters_round_trip ( ) : plot = Bar ( ) plot . add ( 'A' , [ 60 , 75 , 80 , 78 , 83 , 90 ] ) plot . add ( 'B' , [ 92 , 87 , 81 , 73 , 68 , 55 ] ) before = plot . render ( ) plot . add_xml_filter ( ( lambda T : T ) ) after = plot . render ( ) assert ( before == after )
ensure doing nothing does nothing .