blob: 80c28e8470423e2679624d78092d2c42ef68ee33 [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"
"fmt"
"sort"
"strings"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/internal/event"
"golang.org/x/tools/internal/imports"
"golang.org/x/tools/internal/lsp/debug/tag"
"golang.org/x/tools/internal/lsp/protocol"
"golang.org/x/tools/internal/lsp/source"
"golang.org/x/tools/internal/span"
)
func (s *Server) codeAction(ctx context.Context, params *protocol.CodeActionParams) ([]protocol.CodeAction, error) {
snapshot, fh, ok, release, err := s.beginFileRequest(ctx, params.TextDocument.URI, source.UnknownKind)
defer release()
if !ok {
return nil, err
}
uri := fh.URI()
// Determine the supported actions for this file kind.
supportedCodeActions, ok := snapshot.View().Options().SupportedCodeActions[fh.Kind()]
if !ok {
return nil, fmt.Errorf("no supported code actions for %v file kind", fh.Kind())
}
// The Only field of the context specifies which code actions the client wants.
// If Only is empty, assume that the client wants all of the possible code actions.
var wanted map[protocol.CodeActionKind]bool
if len(params.Context.Only) == 0 {
wanted = supportedCodeActions
} else {
wanted = make(map[protocol.CodeActionKind]bool)
for _, only := range params.Context.Only {
wanted[only] = supportedCodeActions[only]
}
}
if len(wanted) == 0 {
return nil, fmt.Errorf("no supported code action to execute for %s, wanted %v", uri, params.Context.Only)
}
var codeActions []protocol.CodeAction
switch fh.Kind() {
case source.Mod:
// TODO: Support code actions for views with multiple modules.
if snapshot.View().ModFile() == "" {
return nil, nil
}
if diagnostics := params.Context.Diagnostics; len(diagnostics) > 0 {
modQuickFixes, err := moduleQuickFixes(ctx, snapshot, diagnostics)
if err == source.ErrTmpModfileUnsupported {
return nil, nil
}
if err != nil {
return nil, err
}
codeActions = append(codeActions, modQuickFixes...)
}
if wanted[protocol.SourceOrganizeImports] {
action, err := goModTidy(ctx, snapshot)
if err == source.ErrTmpModfileUnsupported {
return nil, nil
}
if err != nil {
return nil, err
}
codeActions = append(codeActions, *action)
}
case source.Go:
// Don't suggest fixes for generated files, since they are generally
// not useful and some editors may apply them automatically on save.
if source.IsGenerated(ctx, snapshot, uri) {
return nil, nil
}
diagnostics := params.Context.Diagnostics
// First, process any missing imports and pair them with the
// diagnostics they fix.
if wantQuickFixes := wanted[protocol.QuickFix] && len(diagnostics) > 0; wantQuickFixes || wanted[protocol.SourceOrganizeImports] {
importEdits, importEditsPerFix, err := source.AllImportsFixes(ctx, snapshot, fh)
if err != nil {
event.Error(ctx, "imports fixes", err, tag.File.Of(fh.URI().Filename()))
}
// Separate this into a set of codeActions per diagnostic, where
// each action is the addition, removal, or renaming of one import.
if wantQuickFixes {
for _, importFix := range importEditsPerFix {
fixes := importDiagnostics(importFix.Fix, diagnostics)
if len(fixes) == 0 {
continue
}
codeActions = append(codeActions, protocol.CodeAction{
Title: importFixTitle(importFix.Fix),
Kind: protocol.QuickFix,
Edit: protocol.WorkspaceEdit{
DocumentChanges: documentChanges(fh, importFix.Edits),
},
Diagnostics: fixes,
})
}
}
// Send all of the import edits as one code action if the file is
// being organized.
if wanted[protocol.SourceOrganizeImports] && len(importEdits) > 0 {
codeActions = append(codeActions, protocol.CodeAction{
Title: "Organize Imports",
Kind: protocol.SourceOrganizeImports,
Edit: protocol.WorkspaceEdit{
DocumentChanges: documentChanges(fh, importEdits),
},
})
}
}
if ctx.Err() != nil {
return nil, ctx.Err()
}
pkgs, err := snapshot.PackagesForFile(ctx, fh.URI(), source.TypecheckFull)
if err != nil {
return nil, err
}
pkg, err := source.WidestPackage(pkgs)
if err != nil {
return nil, err
}
if (wanted[protocol.QuickFix] || wanted[protocol.SourceFixAll]) && len(diagnostics) > 0 {
analysisQuickFixes, highConfidenceEdits, err := analysisFixes(ctx, snapshot, pkg, diagnostics)
if err != nil {
return nil, err
}
if wanted[protocol.QuickFix] {
// Add the quick fixes reported by go/analysis.
codeActions = append(codeActions, analysisQuickFixes...)
// If there are any diagnostics relating to the go.mod file,
// add their corresponding quick fixes.
modQuickFixes, err := moduleQuickFixes(ctx, snapshot, diagnostics)
if err != nil {
// Not a fatal error.
event.Error(ctx, "module suggested fixes failed", err, tag.Directory.Of(snapshot.View().Folder()))
}
codeActions = append(codeActions, modQuickFixes...)
}
if wanted[protocol.SourceFixAll] && len(highConfidenceEdits) > 0 {
codeActions = append(codeActions, protocol.CodeAction{
Title: "Simplifications",
Kind: protocol.SourceFixAll,
Edit: protocol.WorkspaceEdit{
DocumentChanges: highConfidenceEdits,
},
})
}
}
if ctx.Err() != nil {
return nil, ctx.Err()
}
// Add any suggestions that do not necessarily fix any diagnostics.
if wanted[protocol.RefactorRewrite] {
fixes, err := convenienceFixes(ctx, snapshot, pkg, uri, params.Range)
if err != nil {
return nil, err
}
codeActions = append(codeActions, fixes...)
}
if wanted[protocol.RefactorExtract] {
fixes, err := extractionFixes(ctx, snapshot, pkg, uri, params.Range)
if err != nil {
return nil, err
}
codeActions = append(codeActions, fixes...)
}
default:
// Unsupported file kind for a code action.
return nil, nil
}
return codeActions, nil
}
func (s *Server) getSupportedCodeActions() []protocol.CodeActionKind {
allCodeActionKinds := make(map[protocol.CodeActionKind]struct{})
for _, kinds := range s.session.Options().SupportedCodeActions {
for kind := range kinds {
allCodeActionKinds[kind] = struct{}{}
}
}
var result []protocol.CodeActionKind
for kind := range allCodeActionKinds {
result = append(result, kind)
}
sort.Slice(result, func(i, j int) bool {
return result[i] < result[j]
})
return result
}
func importFixTitle(fix *imports.ImportFix) string {
var str string
switch fix.FixType {
case imports.AddImport:
str = fmt.Sprintf("Add import: %s %q", fix.StmtInfo.Name, fix.StmtInfo.ImportPath)
case imports.DeleteImport:
str = fmt.Sprintf("Delete import: %s %q", fix.StmtInfo.Name, fix.StmtInfo.ImportPath)
case imports.SetImportName:
str = fmt.Sprintf("Rename import: %s %q", fix.StmtInfo.Name, fix.StmtInfo.ImportPath)
}
return str
}
func importDiagnostics(fix *imports.ImportFix, diagnostics []protocol.Diagnostic) (results []protocol.Diagnostic) {
for _, diagnostic := range diagnostics {
switch {
// "undeclared name: X" may be an unresolved import.
case strings.HasPrefix(diagnostic.Message, "undeclared name: "):
ident := strings.TrimPrefix(diagnostic.Message, "undeclared name: ")
if ident == fix.IdentName {
results = append(results, diagnostic)
}
// "could not import: X" may be an invalid import.
case strings.HasPrefix(diagnostic.Message, "could not import: "):
ident := strings.TrimPrefix(diagnostic.Message, "could not import: ")
if ident == fix.IdentName {
results = append(results, diagnostic)
}
// "X imported but not used" is an unused import.
// "X imported but not used as Y" is an unused import.
case strings.Contains(diagnostic.Message, " imported but not used"):
idx := strings.Index(diagnostic.Message, " imported but not used")
importPath := diagnostic.Message[:idx]
if importPath == fmt.Sprintf("%q", fix.StmtInfo.ImportPath) {
results = append(results, diagnostic)
}
}
}
return results
}
func analysisFixes(ctx context.Context, snapshot source.Snapshot, pkg source.Package, diagnostics []protocol.Diagnostic) ([]protocol.CodeAction, []protocol.TextDocumentEdit, error) {
if len(diagnostics) == 0 {
return nil, nil, nil
}
var (
codeActions []protocol.CodeAction
sourceFixAllEdits []protocol.TextDocumentEdit
)
for _, diag := range diagnostics {
srcErr, analyzer, ok := findSourceError(ctx, snapshot, pkg.ID(), diag)
if !ok {
continue
}
// If the suggested fix for the diagnostic is expected to be separate,
// see if there are any supported commands available.
if analyzer.Command != nil {
action, err := diagnosticToCommandCodeAction(ctx, snapshot, srcErr, &diag, protocol.QuickFix)
if err != nil {
return nil, nil, err
}
codeActions = append(codeActions, *action)
continue
}
for _, fix := range srcErr.SuggestedFixes {
action := protocol.CodeAction{
Title: fix.Title,
Kind: protocol.QuickFix,
Diagnostics: []protocol.Diagnostic{diag},
Edit: protocol.WorkspaceEdit{},
}
for uri, edits := range fix.Edits {
fh, err := snapshot.GetFile(ctx, uri)
if err != nil {
return nil, nil, err
}
docChanges := documentChanges(fh, edits)
if analyzer.HighConfidence {
sourceFixAllEdits = append(sourceFixAllEdits, docChanges...)
}
action.Edit.DocumentChanges = append(action.Edit.DocumentChanges, docChanges...)
}
codeActions = append(codeActions, action)
}
}
return codeActions, sourceFixAllEdits, nil
}
func findSourceError(ctx context.Context, snapshot source.Snapshot, pkgID string, diag protocol.Diagnostic) (*source.Error, source.Analyzer, bool) {
analyzer := diagnosticToAnalyzer(snapshot, diag.Source, diag.Message)
if analyzer == nil {
return nil, source.Analyzer{}, false
}
analysisErrors, err := snapshot.Analyze(ctx, pkgID, analyzer.Analyzer)
if err != nil {
return nil, source.Analyzer{}, false
}
for _, err := range analysisErrors {
if err.Message != diag.Message {
continue
}
if protocol.CompareRange(err.Range, diag.Range) != 0 {
continue
}
if err.Category != analyzer.Analyzer.Name {
continue
}
// The error matches.
return err, *analyzer, true
}
return nil, source.Analyzer{}, false
}
// diagnosticToAnalyzer return the analyzer associated with a given diagnostic.
// It assumes that the diagnostic's source will be the name of the analyzer.
// If this changes, this approach will need to be reworked.
func diagnosticToAnalyzer(snapshot source.Snapshot, src, msg string) (analyzer *source.Analyzer) {
// Make sure that the analyzer we found is enabled.
defer func() {
if analyzer != nil && !analyzer.IsEnabled(snapshot.View()) {
analyzer = nil
}
}()
if a, ok := snapshot.View().Options().DefaultAnalyzers[src]; ok {
return &a
}
if a, ok := snapshot.View().Options().StaticcheckAnalyzers[src]; ok {
return &a
}
if a, ok := snapshot.View().Options().ConvenienceAnalyzers[src]; ok {
return &a
}
// Hack: We publish diagnostics with the source "compiler" for type errors,
// but these analyzers have different names. Try both possibilities.
if a, ok := snapshot.View().Options().TypeErrorAnalyzers[src]; ok {
return &a
}
if src != "compiler" {
return nil
}
for _, a := range snapshot.View().Options().TypeErrorAnalyzers {
if a.FixesError(msg) {
return &a
}
}
return nil
}
func convenienceFixes(ctx context.Context, snapshot source.Snapshot, pkg source.Package, uri span.URI, rng protocol.Range) ([]protocol.CodeAction, error) {
var analyzers []*analysis.Analyzer
for _, a := range snapshot.View().Options().ConvenienceAnalyzers {
if !a.IsEnabled(snapshot.View()) {
continue
}
if a.Command == nil {
event.Error(ctx, "convenienceFixes", fmt.Errorf("no suggested fixes for convenience analyzer %s", a.Analyzer.Name))
continue
}
analyzers = append(analyzers, a.Analyzer)
}
diagnostics, err := snapshot.Analyze(ctx, pkg.ID(), analyzers...)
if err != nil {
return nil, err
}
var codeActions []protocol.CodeAction
for _, d := range diagnostics {
// For now, only show diagnostics for matching lines. Maybe we should
// alter this behavior in the future, depending on the user experience.
if d.URI != uri {
continue
}
if !protocol.Intersect(d.Range, rng) {
continue
}
action, err := diagnosticToCommandCodeAction(ctx, snapshot, d, nil, protocol.RefactorRewrite)
if err != nil {
return nil, err
}
codeActions = append(codeActions, *action)
}
return codeActions, nil
}
func diagnosticToCommandCodeAction(ctx context.Context, snapshot source.Snapshot, e *source.Error, d *protocol.Diagnostic, kind protocol.CodeActionKind) (*protocol.CodeAction, error) {
// The fix depends on the category of the analyzer. The diagnostic may be
// nil, so use the error's category.
analyzer := diagnosticToAnalyzer(snapshot, e.Category, e.Message)
if analyzer == nil {
return nil, fmt.Errorf("no convenience analyzer for category %s", e.Category)
}
if analyzer.Command == nil {
return nil, fmt.Errorf("no command for convenience analyzer %s", analyzer.Analyzer.Name)
}
jsonArgs, err := source.MarshalArgs(e.URI, e.Range)
if err != nil {
return nil, err
}
var diagnostics []protocol.Diagnostic
if d != nil {
diagnostics = append(diagnostics, *d)
}
return &protocol.CodeAction{
Title: e.Message,
Kind: kind,
Diagnostics: diagnostics,
Command: &protocol.Command{
Command: analyzer.Command.Name,
Title: e.Message,
Arguments: jsonArgs,
},
}, nil
}
func extractionFixes(ctx context.Context, snapshot source.Snapshot, pkg source.Package, uri span.URI, rng protocol.Range) ([]protocol.CodeAction, error) {
if rng.Start == rng.End {
return nil, nil
}
fh, err := snapshot.GetFile(ctx, uri)
if err != nil {
return nil, err
}
jsonArgs, err := source.MarshalArgs(uri, rng)
if err != nil {
return nil, err
}
var actions []protocol.CodeAction
for _, command := range []*source.Command{
source.CommandExtractFunction,
source.CommandExtractVariable,
} {
if !command.Applies(ctx, snapshot, fh, rng) {
continue
}
actions = append(actions, protocol.CodeAction{
Title: command.Title,
Kind: protocol.RefactorExtract,
Command: &protocol.Command{
Command: command.Name,
Arguments: jsonArgs,
},
})
}
return actions, nil
}
func documentChanges(fh source.VersionedFileHandle, edits []protocol.TextEdit) []protocol.TextDocumentEdit {
return []protocol.TextDocumentEdit{
{
TextDocument: protocol.VersionedTextDocumentIdentifier{
Version: fh.Version(),
TextDocumentIdentifier: protocol.TextDocumentIdentifier{
URI: protocol.URIFromSpanURI(fh.URI()),
},
},
Edits: edits,
},
}
}
func moduleQuickFixes(ctx context.Context, snapshot source.Snapshot, diagnostics []protocol.Diagnostic) ([]protocol.CodeAction, error) {
modFH, err := snapshot.GetFile(ctx, snapshot.View().ModFile())
if err != nil {
return nil, err
}
tidied, err := snapshot.ModTidy(ctx, modFH)
if err == source.ErrTmpModfileUnsupported {
return nil, nil
}
if err != nil {
return nil, err
}
var quickFixes []protocol.CodeAction
for _, e := range tidied.Errors {
var diag *protocol.Diagnostic
for _, d := range diagnostics {
if sameDiagnostic(d, e) {
diag = &d
break
}
}
if diag == nil {
continue
}
for _, fix := range e.SuggestedFixes {
action := protocol.CodeAction{
Title: fix.Title,
Kind: protocol.QuickFix,
Diagnostics: []protocol.Diagnostic{*diag},
Edit: protocol.WorkspaceEdit{},
}
for uri, edits := range fix.Edits {
if uri != modFH.URI() {
continue
}
action.Edit.DocumentChanges = append(action.Edit.DocumentChanges, protocol.TextDocumentEdit{
TextDocument: protocol.VersionedTextDocumentIdentifier{
Version: modFH.Version(),
TextDocumentIdentifier: protocol.TextDocumentIdentifier{
URI: protocol.URIFromSpanURI(modFH.URI()),
},
},
Edits: edits,
})
}
quickFixes = append(quickFixes, action)
}
}
return quickFixes, nil
}
func sameDiagnostic(d protocol.Diagnostic, e source.Error) bool {
return d.Message == e.Message && protocol.CompareRange(d.Range, e.Range) == 0 && d.Source == e.Category
}
func goModTidy(ctx context.Context, snapshot source.Snapshot) (*protocol.CodeAction, error) {
modFH, err := snapshot.GetFile(ctx, snapshot.View().ModFile())
if err != nil {
return nil, err
}
tidied, err := snapshot.ModTidy(ctx, modFH)
if err != nil {
return nil, err
}
left, err := modFH.Read()
if err != nil {
return nil, err
}
right := tidied.TidiedContent
edits := snapshot.View().Options().ComputeEdits(modFH.URI(), string(left), string(right))
protocolEdits, err := source.ToProtocolEdits(tidied.Parsed.Mapper, edits)
if err != nil {
return nil, err
}
return &protocol.CodeAction{
Title: "Tidy",
Kind: protocol.SourceOrganizeImports,
Edit: protocol.WorkspaceEdit{
DocumentChanges: []protocol.TextDocumentEdit{{
TextDocument: protocol.VersionedTextDocumentIdentifier{
Version: modFH.Version(),
TextDocumentIdentifier: protocol.TextDocumentIdentifier{
URI: protocol.URIFromSpanURI(modFH.URI()),
},
},
Edits: protocolEdits,
}},
},
}, nil
}