| // 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" |
| "fmt" |
| "strings" |
| |
| "golang.org/x/tools/gopls/internal/lsp/protocol" |
| "golang.org/x/tools/gopls/internal/lsp/source" |
| "golang.org/x/tools/gopls/internal/lsp/source/completion" |
| "golang.org/x/tools/gopls/internal/lsp/template" |
| "golang.org/x/tools/gopls/internal/lsp/work" |
| "golang.org/x/tools/internal/event" |
| "golang.org/x/tools/internal/event/tag" |
| ) |
| |
| func (s *Server) completion(ctx context.Context, params *protocol.CompletionParams) (*protocol.CompletionList, error) { |
| ctx, done := event.Start(ctx, "lsp.Server.completion", tag.URI.Of(params.TextDocument.URI)) |
| defer done() |
| |
| snapshot, fh, ok, release, err := s.beginFileRequest(ctx, params.TextDocument.URI, source.UnknownKind) |
| defer release() |
| if !ok { |
| return nil, err |
| } |
| var candidates []completion.CompletionItem |
| var surrounding *completion.Selection |
| switch snapshot.View().FileKind(fh) { |
| case source.Go: |
| candidates, surrounding, err = completion.Completion(ctx, snapshot, fh, params.Position, params.Context) |
| case source.Mod: |
| candidates, surrounding = nil, nil |
| case source.Work: |
| cl, err := work.Completion(ctx, snapshot, fh, params.Position) |
| if err != nil { |
| break |
| } |
| return cl, nil |
| case source.Tmpl: |
| var cl *protocol.CompletionList |
| cl, err = template.Completion(ctx, snapshot, fh, params.Position, params.Context) |
| if err != nil { |
| break // use common error handling, candidates==nil |
| } |
| return cl, nil |
| } |
| if err != nil { |
| event.Error(ctx, "no completions found", err, tag.Position.Of(params.Position)) |
| } |
| if candidates == nil { |
| return &protocol.CompletionList{ |
| IsIncomplete: true, |
| Items: []protocol.CompletionItem{}, |
| }, nil |
| } |
| |
| rng, err := surrounding.Range() |
| if err != nil { |
| return nil, err |
| } |
| |
| // When using deep completions/fuzzy matching, report results as incomplete so |
| // client fetches updated completions after every key stroke. |
| options := snapshot.View().Options() |
| incompleteResults := options.DeepCompletion || options.Matcher == source.Fuzzy |
| |
| items := toProtocolCompletionItems(candidates, rng, options) |
| |
| return &protocol.CompletionList{ |
| IsIncomplete: incompleteResults, |
| Items: items, |
| }, nil |
| } |
| |
| func toProtocolCompletionItems(candidates []completion.CompletionItem, rng protocol.Range, options *source.Options) []protocol.CompletionItem { |
| var ( |
| items = make([]protocol.CompletionItem, 0, len(candidates)) |
| numDeepCompletionsSeen int |
| ) |
| for i, candidate := range candidates { |
| // Limit the number of deep completions to not overwhelm the user in cases |
| // with dozens of deep completion matches. |
| if candidate.Depth > 0 { |
| if !options.DeepCompletion { |
| continue |
| } |
| if numDeepCompletionsSeen >= completion.MaxDeepCompletions { |
| continue |
| } |
| numDeepCompletionsSeen++ |
| } |
| insertText := candidate.InsertText |
| if options.InsertTextFormat == protocol.SnippetTextFormat { |
| insertText = candidate.Snippet() |
| } |
| |
| // This can happen if the client has snippets disabled but the |
| // candidate only supports snippet insertion. |
| if insertText == "" { |
| continue |
| } |
| |
| doc := &protocol.Or_CompletionItem_documentation{ |
| Value: protocol.MarkupContent{ |
| Kind: protocol.Markdown, |
| Value: source.CommentToMarkdown(candidate.Documentation, options), |
| }, |
| } |
| if options.PreferredContentFormat != protocol.Markdown { |
| doc.Value = candidate.Documentation |
| } |
| item := protocol.CompletionItem{ |
| Label: candidate.Label, |
| Detail: candidate.Detail, |
| Kind: candidate.Kind, |
| TextEdit: &protocol.TextEdit{ |
| NewText: insertText, |
| Range: rng, |
| }, |
| InsertTextFormat: &options.InsertTextFormat, |
| AdditionalTextEdits: candidate.AdditionalTextEdits, |
| // This is a hack so that the client sorts completion results in the order |
| // according to their score. This can be removed upon the resolution of |
| // https://github.com/Microsoft/language-server-protocol/issues/348. |
| SortText: fmt.Sprintf("%05d", i), |
| |
| // Trim operators (VSCode doesn't like weird characters in |
| // filterText). |
| FilterText: strings.TrimLeft(candidate.InsertText, "&*"), |
| |
| Preselect: i == 0, |
| Documentation: doc, |
| Tags: nonNilSliceCompletionItemTag(candidate.Tags), |
| Deprecated: candidate.Deprecated, |
| } |
| items = append(items, item) |
| } |
| return items |
| } |