'If the SSHUserAuthClient doesn\'t return anything from signData,
the client should start the authentication over again by requesting
\'none\' authentication.'

def test_publickey_without_privatekey(self):

    authClient = ClientAuthWithoutPrivateKey('foo', FakeTransport.Service())
    authClient.transport = FakeTransport(None)
    authClient.transport.sessionID = 'test'
    authClient.serviceStarted()
    authClient.tryAuth('publickey')
    authClient.transport.packets = []
    self.assertIsNone(authClient.ssh_USERAUTH_PK_OK(''))
    self.assertEqual(authClient.transport.packets, [(userauth.MSG_USERAUTH_REQUEST, ((NS('foo') + NS('nancy')) + NS('none')))])
