'When an attempt is made to open an unknown channel type, the L{Deferred}
returned by L{SSHChannel.sendRequest} fires its errback.'

def test_unknownChannel(self):

    d = self.assertFailure(self._ourServerOurClientTest('crazy-unknown-channel'), Exception)
    def cbFailed(ignored):
        errors = self.flushLoggedErrors(error.ConchError)
        self.assertEqual(errors[0].value.args, (3, 'unknown    channel'))
        self.assertEqual(len(errors), 1)
    d.addCallback(cbFailed)
    return d
