jsonrpc2: add testcase taken from golang/tools@aa71c3f324

https://github.com/golang/tools/blob/aa71c3f32488bfee7774668abdf1ae045e013079/internal/jsonrpc2/jsonrpc2_test.go

Author: zchee

jsonrpc2_test.go

@@ -0,0 +1,142 @@
+// Copyright 2019 The go-language-server Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package jsonrpc2_test
+
+import (
+	"context"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io"
+	"path"
+	"reflect"
+	"testing"
+
+	"go.uber.org/zap"
+
+	"github.com/go-language-server/jsonrpc2"
+)
+
+var logRPC = flag.Bool("logrpc", false, "Enable jsonrpc2 communication logging")
+
+type callTest struct {
+	method string
+	params interface{}
+	expect interface{}
+}
+
+var callTests = []callTest{
+	{"no_args", nil, true},
+	{"one_string", "fish", "got:fish"},
+	{"one_number", 10, "got:10"},
+	{"join", []string{"a", "b", "c"}, "a/b/c"},
+	//TODO: expand the test cases
+}
+
+func (test *callTest) newResults() interface{} {
+	switch e := test.expect.(type) {
+	case []interface{}:
+		var r []interface{}
+		for _, v := range e {
+			r = append(r, reflect.New(reflect.TypeOf(v)).Interface())
+		}
+		return r
+	case nil:
+		return nil
+	default:
+		return reflect.New(reflect.TypeOf(test.expect)).Interface()
+	}
+}
+
+func (test *callTest) verifyResults(t *testing.T, results interface{}) {
+	if results == nil {
+		return
+	}
+	val := reflect.Indirect(reflect.ValueOf(results)).Interface()
+	if !reflect.DeepEqual(val, test.expect) {
+		t.Errorf("%v:Results are incorrect, got %+v expect %+v", test.method, val, test.expect)
+	}
+}
+
+func prepare(ctx context.Context, t *testing.T) (*jsonrpc2.Conn, *jsonrpc2.Conn) {
+	aR, bW := io.Pipe()
+	bR, aW := io.Pipe()
+	a := run(ctx, t, aR, aW)
+	b := run(ctx, t, bR, bW)
+	return a, b
+}
+
+func run(ctx context.Context, t *testing.T, r io.ReadCloser, w io.WriteCloser) *jsonrpc2.Conn {
+	stream := jsonrpc2.NewStream(r, w)
+	conn := jsonrpc2.NewConn(stream)
+	conn.Handler = handle
+
+	if *logRPC {
+		conn.Logger, _ = zap.NewDevelopment()
+	}
+
+	go func() {
+		defer func() {
+			r.Close()
+			w.Close()
+		}()
+
+		if err := conn.Run(ctx); err != nil {
+			t.Fatalf("Stream failed: %v", err)
+		}
+	}()
+
+	return conn
+}
+
+func handle(ctx context.Context, c *jsonrpc2.Conn, r *jsonrpc2.Request) {
+	switch r.Method {
+	case "no_args":
+		if r.Params != nil {
+			c.Reply(ctx, r, nil, jsonrpc2.Errorf(jsonrpc2.CodeInvalidParams, "Expected no params"))
+			return
+		}
+		c.Reply(ctx, r, true, nil)
+	case "one_string":
+		var v string
+		if err := json.Unmarshal(*r.Params, &v); err != nil {
+			c.Reply(ctx, r, nil, jsonrpc2.Errorf(jsonrpc2.CodeParseError, "%v", err.Error()))
+			return
+		}
+		c.Reply(ctx, r, "got:"+v, nil)
+	case "one_number":
+		var v int
+		if err := json.Unmarshal(*r.Params, &v); err != nil {
+			c.Reply(ctx, r, nil, jsonrpc2.Errorf(jsonrpc2.CodeParseError, "%v", err.Error()))
+			return
+		}
+		c.Reply(ctx, r, fmt.Sprintf("got:%d", v), nil)
+	case "join":
+		var v []string
+		if err := json.Unmarshal(*r.Params, &v); err != nil {
+			c.Reply(ctx, r, nil, jsonrpc2.Errorf(jsonrpc2.CodeParseError, "%v", err.Error()))
+			return
+		}
+		c.Reply(ctx, r, path.Join(v...), nil)
+	default:
+		c.Reply(ctx, r, nil, jsonrpc2.Errorf(jsonrpc2.CodeMethodNotFound, "method %q not found", r.Method))
+	}
+}
+
+func TestCall(t *testing.T) {
+	ctx := context.Background()
+	a, b := prepare(ctx, t)
+	for _, test := range callTests {
+		results := test.newResults()
+		if err := a.Call(ctx, test.method, test.params, results); err != nil {
+			t.Fatalf("%v:Call failed: %v", test.method, err)
+		}
+		test.verifyResults(t, results)
+		if err := b.Call(ctx, test.method, test.params, results); err != nil {
+			t.Fatalf("%v:Call failed: %v", test.method, err)
+		}
+		test.verifyResults(t, results)
+	}
+}