1// Copyright 2019 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package cmd
6
7import (
8	"context"
9	"flag"
10	"fmt"
11	"sort"
12
13	"golang.org/x/tools/internal/lsp/protocol"
14	"golang.org/x/tools/internal/span"
15	"golang.org/x/tools/internal/tool"
16)
17
18// references implements the references verb for gopls
19type references struct {
20	IncludeDeclaration bool `flag:"d" help:"include the declaration of the specified identifier in the results"`
21
22	app *Application
23}
24
25func (r *references) Name() string      { return "references" }
26func (r *references) Usage() string     { return "<position>" }
27func (r *references) ShortHelp() string { return "display selected identifier's references" }
28func (r *references) DetailedHelp(f *flag.FlagSet) {
29	fmt.Fprint(f.Output(), `
30Example:
31
32  $ # 1-indexed location (:line:column or :#offset) of the target identifier
33  $ gopls references helper/helper.go:8:6
34  $ gopls references helper/helper.go:#53
35
36  gopls references flags are:
37`)
38	f.PrintDefaults()
39}
40
41func (r *references) Run(ctx context.Context, args ...string) error {
42	if len(args) != 1 {
43		return tool.CommandLineErrorf("references expects 1 argument (position)")
44	}
45
46	conn, err := r.app.connect(ctx)
47	if err != nil {
48		return err
49	}
50	defer conn.terminate(ctx)
51
52	from := span.Parse(args[0])
53	file := conn.AddFile(ctx, from.URI())
54	if file.err != nil {
55		return file.err
56	}
57	loc, err := file.mapper.Location(from)
58	if err != nil {
59		return err
60	}
61	p := protocol.ReferenceParams{
62		Context: protocol.ReferenceContext{
63			IncludeDeclaration: r.IncludeDeclaration,
64		},
65		TextDocumentPositionParams: protocol.TextDocumentPositionParams{
66			TextDocument: protocol.TextDocumentIdentifier{URI: loc.URI},
67			Position:     loc.Range.Start,
68		},
69	}
70	locations, err := conn.References(ctx, &p)
71	if err != nil {
72		return err
73	}
74	var spans []string
75	for _, l := range locations {
76		f := conn.AddFile(ctx, fileURI(l.URI))
77		// convert location to span for user-friendly 1-indexed line
78		// and column numbers
79		span, err := f.mapper.Span(l)
80		if err != nil {
81			return err
82		}
83		spans = append(spans, fmt.Sprint(span))
84	}
85
86	sort.Strings(spans)
87	for _, s := range spans {
88		fmt.Println(s)
89	}
90	return nil
91}
92