'If L{smtp.SMTPClient.sendError} is called with an exception which is
not an L{SMTPClientError}, it disconnects its transport without
writing anything more to it.'

def test_sendOtherError(self):

    client = smtp.SMTPClient(None)
    transport = StringTransport()
    client.makeConnection(transport)
    client.sendError(Exception('foo'))
    self.assertEqual(transport.value(), '')
    self.assertTrue(transport.disconnecting)
