'SSHSession.extReceived() passed data of type EXTENDED_DATA_STDERR along
to the client.  If the data comes before there is a client, or if the
data is not of type EXTENDED_DATA_STDERR, it is discared.'

def test_client_extReceived(self):

    self.session.extReceived(connection.EXTENDED_DATA_STDERR, '1')
    self.session.extReceived(255, '2')
    self.session.client = StubClient()
    self.session.extReceived(connection.EXTENDED_DATA_STDERR, '3')
    self.assertEqual(self.session.client.transport.err, '3')
