'The I{traceback} renderer of L{FailureElement} renders the failure\'s
stack frames using L{_StackElement}.'

def test_failureElementTraceback(self):

    element = FailureElement(self.failure)
    renderer = element.lookupRenderMethod('traceback')
    tag = tags.div()
    result = renderer(None, tag)
    self.assertIsInstance(result, _StackElement)
    self.assertIdentical(result.stackFrames, self.failure.frames)
    self.assertEqual([tag], result.loader.load())
