case debugSetClientPingDuration:
		c.clientPingInterval = args[0].(time.Duration)
	case debugAddToDeadline:
		c.addDeadline = args[0].(time.Duration)
	case debugIsOutgoingClosed:
		// params: muxID uint64, isClosed func(bool)
		muxID := args[0].(uint64)
		resp := args[1].(func(b bool))
		mid, ok := c.outgoing.Load(muxID)
		if !ok || mid == nil {
			resp(true)
			return
		}
		mid.respMu.Lock()