'Test the case where the association type (assoc_type) returned
in an unsupported-type response is absent.'

def testEmptyAssocType(self):

    msg = Message(self.endpoint.preferredNamespace())
    msg.setArg(OPENID_NS, 'error', 'Unsupported    type')
    msg.setArg(OPENID_NS, 'error_code', 'unsupported-type')
    msg.setArg(OPENID_NS, 'session_type', 'new-session-type')
    self.consumer.return_messages = [msg]
    self.assertEqual(self.consumer._negotiateAssociation(self.endpoint), None)
    self.failUnlessLogMatches('Unsupported    association    type', ('Server    responded    with    unsupported    association    ' + 'session    but    did    not    supply    a    fallback.'))
