blob: d898df4ee112ef6dfb51481fc049ef2a25119340 [file] [log] [blame]
// Copyright 2018 The Go 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 lsp
import (
"bytes"
"context"
"fmt"
"go/ast"
"go/token"
"net/url"
"regexp"
"strconv"
"strings"
"sync"
"golang.org/x/tools/internal/lsp/protocol"
"golang.org/x/tools/internal/lsp/source"
"golang.org/x/tools/internal/span"
"golang.org/x/tools/internal/telemetry/event"
)
func (s *Server) documentLink(ctx context.Context, params *protocol.DocumentLinkParams) ([]protocol.DocumentLink, error) {
// TODO(golang/go#36501): Support document links for go.mod files.
snapshot, fh, ok, err := s.beginFileRequest(params.TextDocument.URI, source.UnknownKind)
if !ok {
return nil, err
}
switch fh.Identity().Kind {
case source.Mod:
return modLinks(ctx, snapshot, fh)
case source.Go:
return goLinks(ctx, snapshot.View(), fh)
}
return nil, nil
}
func modLinks(ctx context.Context, snapshot source.Snapshot, fh source.FileHandle) ([]protocol.DocumentLink, error) {
view := snapshot.View()
file, m, err := snapshot.ModHandle(ctx, fh).Parse(ctx)
if err != nil {
return nil, err
}
var links []protocol.DocumentLink
for _, req := range file.Require {
dep := []byte(req.Mod.Path)
s, e := req.Syntax.Start.Byte, req.Syntax.End.Byte
i := bytes.Index(m.Content[s:e], dep)
if i == -1 {
continue
}
// Shift the start position to the location of the
// dependency within the require statement.
start, end := token.Pos(s+i), token.Pos(s+i+len(dep))
target := fmt.Sprintf("https://%s/mod/%s", view.Options().LinkTarget, req.Mod.String())
if l, err := toProtocolLink(view, m, target, start, end, source.Mod); err == nil {
links = append(links, l)
} else {
event.Error(ctx, "failed to create protocol link", err)
}
}
// TODO(ridersofrohan): handle links for replace and exclude directives
if syntax := file.Syntax; syntax == nil {
return links, nil
}
// Get all the links that are contained in the comments of the file.
for _, expr := range file.Syntax.Stmt {
comments := expr.Comment()
if comments == nil {
continue
}
for _, cmt := range comments.Before {
links = append(links, findLinksInString(ctx, view, cmt.Token, token.Pos(cmt.Start.Byte), m, source.Mod)...)
}
for _, cmt := range comments.Suffix {
links = append(links, findLinksInString(ctx, view, cmt.Token, token.Pos(cmt.Start.Byte), m, source.Mod)...)
}
for _, cmt := range comments.After {
links = append(links, findLinksInString(ctx, view, cmt.Token, token.Pos(cmt.Start.Byte), m, source.Mod)...)
}
}
return links, nil
}
func goLinks(ctx context.Context, view source.View, fh source.FileHandle) ([]protocol.DocumentLink, error) {
phs, err := view.Snapshot().PackageHandles(ctx, fh)
if err != nil {
return nil, err
}
ph, err := source.WidestPackageHandle(phs)
if err != nil {
return nil, err
}
file, _, m, _, err := view.Session().Cache().ParseGoHandle(fh, source.ParseFull).Parse(ctx)
if err != nil {
return nil, err
}
var links []protocol.DocumentLink
ast.Inspect(file, func(node ast.Node) bool {
switch n := node.(type) {
case *ast.ImportSpec:
// For import specs, provide a link to a documentation website, like https://pkg.go.dev.
if target, err := strconv.Unquote(n.Path.Value); err == nil {
if mod, version, ok := moduleAtVersion(ctx, target, ph); ok && strings.ToLower(view.Options().LinkTarget) == "pkg.go.dev" {
target = strings.Replace(target, mod, mod+"@"+version, 1)
}
target = fmt.Sprintf("https://%s/%s", view.Options().LinkTarget, target)
// Account for the quotation marks in the positions.
start, end := n.Path.Pos()+1, n.Path.End()-1
if l, err := toProtocolLink(view, m, target, start, end, source.Go); err == nil {
links = append(links, l)
} else {
event.Error(ctx, "failed to create protocol link", err)
}
}
return false
case *ast.BasicLit:
// Look for links in string literals.
if n.Kind == token.STRING {
links = append(links, findLinksInString(ctx, view, n.Value, n.Pos(), m, source.Go)...)
}
return false
}
return true
})
// Look for links in comments.
for _, commentGroup := range file.Comments {
for _, comment := range commentGroup.List {
links = append(links, findLinksInString(ctx, view, comment.Text, comment.Pos(), m, source.Go)...)
}
}
return links, nil
}
func moduleAtVersion(ctx context.Context, target string, ph source.PackageHandle) (string, string, bool) {
pkg, err := ph.Check(ctx)
if err != nil {
return "", "", false
}
impPkg, err := pkg.GetImport(target)
if err != nil {
return "", "", false
}
if impPkg.Module() == nil {
return "", "", false
}
version, modpath := impPkg.Module().Version, impPkg.Module().Path
if modpath == "" || version == "" {
return "", "", false
}
return modpath, version, true
}
func findLinksInString(ctx context.Context, view source.View, src string, pos token.Pos, m *protocol.ColumnMapper, fileKind source.FileKind) []protocol.DocumentLink {
var links []protocol.DocumentLink
for _, index := range view.Options().URLRegexp.FindAllIndex([]byte(src), -1) {
start, end := index[0], index[1]
startPos := token.Pos(int(pos) + start)
endPos := token.Pos(int(pos) + end)
url, err := url.Parse(src[start:end])
if err != nil {
event.Error(ctx, "failed to parse matching URL", err)
continue
}
// If the URL has no scheme, use https.
if url.Scheme == "" {
url.Scheme = "https"
}
l, err := toProtocolLink(view, m, url.String(), startPos, endPos, fileKind)
if err != nil {
event.Error(ctx, "failed to create protocol link", err)
continue
}
links = append(links, l)
}
// Handle golang/go#1234-style links.
r := getIssueRegexp()
for _, index := range r.FindAllIndex([]byte(src), -1) {
start, end := index[0], index[1]
startPos := token.Pos(int(pos) + start)
endPos := token.Pos(int(pos) + end)
matches := r.FindStringSubmatch(src)
if len(matches) < 4 {
continue
}
org, repo, number := matches[1], matches[2], matches[3]
target := fmt.Sprintf("https://github.com/%s/%s/issues/%s", org, repo, number)
l, err := toProtocolLink(view, m, target, startPos, endPos, fileKind)
if err != nil {
event.Error(ctx, "failed to create protocol link", err)
continue
}
links = append(links, l)
}
return links
}
func getIssueRegexp() *regexp.Regexp {
once.Do(func() {
issueRegexp = regexp.MustCompile(`(\w+)/([\w-]+)#([0-9]+)`)
})
return issueRegexp
}
var (
once sync.Once
issueRegexp *regexp.Regexp
)
func toProtocolLink(view source.View, m *protocol.ColumnMapper, target string, start, end token.Pos, fileKind source.FileKind) (protocol.DocumentLink, error) {
var rng protocol.Range
switch fileKind {
case source.Go:
spn, err := span.NewRange(view.Session().Cache().FileSet(), start, end).Span()
if err != nil {
return protocol.DocumentLink{}, err
}
rng, err = m.Range(spn)
if err != nil {
return protocol.DocumentLink{}, err
}
case source.Mod:
s, e := int(start), int(end)
line, col, err := m.Converter.ToPosition(s)
if err != nil {
return protocol.DocumentLink{}, err
}
start := span.NewPoint(line, col, s)
line, col, err = m.Converter.ToPosition(e)
if err != nil {
return protocol.DocumentLink{}, err
}
end := span.NewPoint(line, col, e)
rng, err = m.Range(span.New(m.URI, start, end))
if err != nil {
return protocol.DocumentLink{}, err
}
}
return protocol.DocumentLink{
Range: rng,
Target: target,
}, nil
}