blob: 24dee1b9a8dae3faa04c23ee65a7e9749f08fff3 [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 (
"context"
"golang.org/x/tools/internal/event"
"golang.org/x/tools/internal/lsp/debug/tag"
"golang.org/x/tools/internal/lsp/protocol"
"golang.org/x/tools/internal/lsp/source"
)
func (s *Server) signatureHelp(ctx context.Context, params *protocol.SignatureHelpParams) (*protocol.SignatureHelp, error) {
snapshot, fh, ok, release, err := s.beginFileRequest(ctx, params.TextDocument.URI, source.Go)
defer release()
if !ok {
return nil, err
}
info, activeParameter, err := source.SignatureHelp(ctx, snapshot, fh, params.Position)
if err != nil {
event.Error(ctx, "no signature help", err, tag.Position.Of(params.Position))
return nil, nil
}
return &protocol.SignatureHelp{
Signatures: []protocol.SignatureInformation{*info},
ActiveParameter: uint32(activeParameter),
}, nil
}