blob: 52f8a7a9abf67322d9bffe8debd11429ef1e59b4 [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/lsp/protocol"
"golang.org/x/tools/internal/lsp/source"
"golang.org/x/tools/internal/span"
"golang.org/x/tools/internal/telemetry/log"
"golang.org/x/tools/internal/telemetry/tag"
)
func (s *Server) signatureHelp(ctx context.Context, params *protocol.SignatureHelpParams) (*protocol.SignatureHelp, error) {
uri := span.NewURI(params.TextDocument.URI)
view, err := s.session.ViewOf(uri)
if err != nil {
return nil, err
}
snapshot := view.Snapshot()
f, err := view.GetFile(ctx, uri)
if err != nil {
return nil, err
}
info, err := source.SignatureHelp(ctx, snapshot, f, params.Position)
if err != nil {
log.Print(ctx, "no signature help", tag.Of("At", params.Position), tag.Of("Failure", err))
return nil, nil
}
return toProtocolSignatureHelp(info), nil
}
func toProtocolSignatureHelp(info *source.SignatureInformation) *protocol.SignatureHelp {
return &protocol.SignatureHelp{
ActiveParameter: float64(info.ActiveParameter),
ActiveSignature: 0, // there is only ever one possible signature
Signatures: []protocol.SignatureInformation{
{
Label: info.Label,
Documentation: info.Documentation,
Parameters: toProtocolParameterInformation(info.Parameters),
},
},
}
}
func toProtocolParameterInformation(info []source.ParameterInformation) []protocol.ParameterInformation {
var result []protocol.ParameterInformation
for _, p := range info {
result = append(result, protocol.ParameterInformation{
Label: p.Label,
})
}
return result
}