def test_definedRenderer(self):
        class ElementWithRenderMethod(Element):
            def foo(self, request, tag):
                return "bar"
            renderer(foo)
        foo = ElementWithRenderMethod().renderer("foo")
        self.assertEqual(foo(None, None), "bar")
When called with the name of a defined render method, L{Element.renderer}
dataset/ETHPy150Open twisted/nevow/nevow/test/test_element.py/ElementTests.test_definedRenderer