rpcnil_test.go

// server.go
package main

import (
	"fmt"
	"log"
	"net"
	"net/rpc"
	"testing"
)

type Args struct {
	X *int
	Y *int
}

type Calculator struct{}

func (t *Calculator) Add(args Args, reply *int) error {

	if args.X == nil && args.Y == nil {
		return fmt.Errorf("X and Y are nil")
	}
	if args.X == nil {
		return fmt.Errorf("X is nil")
	}
	if args.Y == nil {
		return fmt.Errorf("Y is nil")
	}

	*reply = *args.X + *args.Y
	return nil
}

func server(listener net.Listener) {
	cal := new(Calculator)
	rpc.Register(cal)
	for {
		if conn, err := listener.Accept(); err != nil {
			log.Fatal("accept error: " + err.Error())
		} else {
			log.Printf("new connection established\n")
			go rpc.ServeConn(conn)
		}
	}
}

func TestRPCNil(t *testing.T) {

	listener, err := net.Listen("tcp", ":1234")
	if err != nil {
		t.Fatalf("Could not listen: %s", err)
	}
	go server(listener)
	client, err := rpc.Dial("tcp", "127.0.0.1:1234")
	if err != nil {
		t.Fatal("dialing:", err)
	}

	zero := 0
	seven := 7
	eight := 8
	args := Args{&seven, &eight}
	var reply int
	err = client.Call("Calculator.Add", args, &reply)
	if err != nil {
		t.Fatal("arith error:", err)
	}
	t.Logf("Result: %d+%d=%d", *args.X, *args.Y, reply)

	args = Args{&zero,&seven}
	err = client.Call("Calculator.Add", args, &reply)
	if err != nil {
		t.Fatal("arith error:", err)
	}

}