681   def ExpectNoPacketsOn(self, netid, msg):  argument
687     self.assertFalse(packets, msg + ": unexpected packet: " + firstpacket)
689   def ExpectPacketOn(self, netid, msg, expected):  argument
700     self.assertTrue(packets, msg + ": received no packets")
715           "%s: diff with last packet:\n%s" % (msg, e.message))
736     msg = "Receiving %s on %s to %s IP, %s" % (desc, iif, ip_if, extra)
738       msg += ": Expecting %s on %s" % (reply_desc, iif)
740       msg += ": Expecting no packets on %s" % iif
741     return msg
743   def _ReceiveAndExpectResponse(self, netid, packet, reply, msg):  argument
746       return self.ExpectPacketOn(netid, msg, reply)
748       self.ExpectNoPacketsOn(netid, msg)