'A L{defer.Deferred} without a canceller must errback with a
L{defer.CancelledError} and not callback.'

def test_noCanceller(self):

    d = defer.Deferred()
    d.addCallbacks(self._callback, self._errback)
    d.cancel()
    self.assertEqual(self.errbackResults.type, defer.CancelledError)
    self.assertIsNone(self.callbackResults)
