'L{Element.render} loads a document from the C{loader} attribute and
returns it.'

def test_render(self):

    class TemplateLoader(object, ):
        def load(self):
            return 'result'
    class StubElement(Element, ):
        loader = TemplateLoader()
    element = StubElement()
    self.assertEqual(element.render(None), 'result')
