mirror of
https://github.com/golang/go
synced 2024-10-01 01:18:32 -06:00
de023d59a5
With #34111, we are forwarding the LSP from one gopls instance to another. This exposed an asymmetry in our LSP dispatching: for both ClientDispatcher and ServerDispatcher, we unmarshal to non-nil response structs. This means that when forwarding the LSP, we translate empty JSON responses (corresponding to nil values) into the non-nil zero value. This causes problems for some editors, as reported in #37570. Fix it by instead unmarshaling to a pointer. This is, of course, a somewhat dangerous change. I fixed the one NPE that occurred in tests, and have done some mild manual testing. I wouldn't be surprised if we discover more NPEs later on, but I still think this is the right change to make. Updates golang/go#34111 Fixes golang/go#37570 Change-Id: Ie69e92d2821c829cdfc4f4ab303679a725f1f859 Reviewed-on: https://go-review.googlesource.com/c/tools/+/222058 Reviewed-by: Peter Weinberger <pjw@google.com> Reviewed-by: Rebecca Stambler <rstambler@golang.org> Run-TryBot: Robert Findley <rfindley@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org>
89 lines
2.0 KiB
Go
89 lines
2.0 KiB
Go
// Copyright 2019 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 cmd
|
|
|
|
import (
|
|
"context"
|
|
"flag"
|
|
"fmt"
|
|
|
|
"golang.org/x/tools/internal/lsp/protocol"
|
|
"golang.org/x/tools/internal/span"
|
|
"golang.org/x/tools/internal/tool"
|
|
)
|
|
|
|
// signature implements the signature verb for gopls
|
|
type signature struct {
|
|
app *Application
|
|
}
|
|
|
|
func (r *signature) Name() string { return "signature" }
|
|
func (r *signature) Usage() string { return "<position>" }
|
|
func (r *signature) ShortHelp() string { return "display selected identifier's signature" }
|
|
func (r *signature) DetailedHelp(f *flag.FlagSet) {
|
|
fmt.Fprint(f.Output(), `
|
|
Example:
|
|
|
|
$ # 1-indexed location (:line:column or :#offset) of the target identifier
|
|
$ gopls signature helper/helper.go:8:6
|
|
$ gopls signature helper/helper.go:#53
|
|
|
|
gopls signature flags are:
|
|
`)
|
|
f.PrintDefaults()
|
|
}
|
|
|
|
func (r *signature) Run(ctx context.Context, args ...string) error {
|
|
if len(args) != 1 {
|
|
return tool.CommandLineErrorf("signature expects 1 argument (position)")
|
|
}
|
|
|
|
conn, err := r.app.connect(ctx)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
defer conn.terminate(ctx)
|
|
|
|
from := span.Parse(args[0])
|
|
file := conn.AddFile(ctx, from.URI())
|
|
if file.err != nil {
|
|
return file.err
|
|
}
|
|
|
|
loc, err := file.mapper.Location(from)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
tdpp := protocol.TextDocumentPositionParams{
|
|
TextDocument: protocol.TextDocumentIdentifier{
|
|
URI: protocol.URIFromSpanURI(from.URI()),
|
|
},
|
|
Position: loc.Range.Start,
|
|
}
|
|
p := protocol.SignatureHelpParams{
|
|
TextDocumentPositionParams: tdpp,
|
|
}
|
|
|
|
s, err := conn.SignatureHelp(ctx, &p)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if s == nil || len(s.Signatures) == 0 {
|
|
return tool.CommandLineErrorf("%v: not a function", from)
|
|
}
|
|
|
|
// there is only ever one possible signature,
|
|
// see toProtocolSignatureHelp in lsp/signature_help.go
|
|
signature := s.Signatures[0]
|
|
fmt.Printf("%s\n", signature.Label)
|
|
if signature.Documentation != "" {
|
|
fmt.Printf("\n%s\n", signature.Documentation)
|
|
}
|
|
|
|
return nil
|
|
}
|