'L{StaticProducer.stopProducing} sets the request instance variable to
None, which indicates to subclasses\' resumeProducing methods that no
more data should be produced.'

def test_stopProducingSetsRequestToNone(self):

    fileObject = StringIO()
    producer = static.StaticProducer(DummyRequest([]), fileObject)
    producer.stopProducing()
    self.assertIdentical(None, producer.request)
