--- /dev/null
+// 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 source
+
+import (
+ "context"
+ "fmt"
+ "strings"
+
+ "golang.org/x/tools/go/analysis"
+ "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/span"
+ errors "golang.org/x/xerrors"
+)
+
+type Diagnostic struct {
+ Range protocol.Range
+ Message string
+ Source string
+ Severity protocol.DiagnosticSeverity
+ Tags []protocol.DiagnosticTag
+
+ Related []RelatedInformation
+}
+
+type SuggestedFix struct {
+ Title string
+ Edits map[span.URI][]protocol.TextEdit
+ Command *protocol.Command
+}
+
+type RelatedInformation struct {
+ URI span.URI
+ Range protocol.Range
+ Message string
+}
+
+func Diagnostics(ctx context.Context, snapshot Snapshot, pkg Package, withAnalysis bool) (map[VersionedFileIdentity][]*Diagnostic, bool, error) {
+ onlyIgnoredFiles := true
+ for _, pgf := range pkg.CompiledGoFiles() {
+ onlyIgnoredFiles = onlyIgnoredFiles && snapshot.IgnoredFile(pgf.URI)
+ }
+ if onlyIgnoredFiles {
+ return nil, false, nil
+ }
+
+ // If we are missing dependencies, it may because the user's workspace is
+ // not correctly configured. Report errors, if possible.
+ var warn bool
+ if len(pkg.MissingDependencies()) > 0 {
+ warn = true
+ }
+ // If we have a package with a single file and errors about "undeclared" symbols,
+ // we may have an ad-hoc package with multiple files. Show a warning message.
+ // TODO(golang/go#36416): Remove this when golang.org/cl/202277 is merged.
+ if len(pkg.CompiledGoFiles()) == 1 && hasUndeclaredErrors(pkg) {
+ warn = true
+ }
+ // Prepare the reports we will send for the files in this package.
+ reports := make(map[VersionedFileIdentity][]*Diagnostic)
+ for _, pgf := range pkg.CompiledGoFiles() {
+ clearReports(snapshot, reports, pgf.URI)
+ }
+ // Prepare any additional reports for the errors in this package.
+ for _, e := range pkg.GetErrors() {
+ // We only need to handle lower-level errors.
+ if e.Kind != ListError {
+ continue
+ }
+ // If no file is associated with the error, pick an open file from the package.
+ if e.URI.Filename() == "" {
+ for _, pgf := range pkg.CompiledGoFiles() {
+ if snapshot.IsOpen(pgf.URI) {
+ e.URI = pgf.URI
+ }
+ }
+ }
+ clearReports(snapshot, reports, e.URI)
+ }
+ // Run diagnostics for the package that this URI belongs to.
+ hadDiagnostics, hadTypeErrors, err := diagnostics(ctx, snapshot, reports, pkg, len(pkg.MissingDependencies()) > 0)
+ if err != nil {
+ return nil, warn, err
+ }
+ if hadDiagnostics || !withAnalysis {
+ return reports, warn, nil
+ }
+ // Exit early if the context has been canceled. This also protects us
+ // from a race on Options, see golang/go#36699.
+ if ctx.Err() != nil {
+ return nil, warn, ctx.Err()
+ }
+ // If we don't have any list or parse errors, run analyses.
+ analyzers := pickAnalyzers(snapshot, hadTypeErrors)
+ if err := analyses(ctx, snapshot, reports, pkg, analyzers); err != nil {
+ event.Error(ctx, "analyses failed", err, tag.Snapshot.Of(snapshot.ID()), tag.Package.Of(pkg.ID()))
+ if ctx.Err() != nil {
+ return nil, warn, ctx.Err()
+ }
+ }
+ return reports, warn, nil
+}
+
+func pickAnalyzers(snapshot Snapshot, hadTypeErrors bool) map[string]Analyzer {
+ analyzers := make(map[string]Analyzer)
+
+ // Always run convenience analyzers.
+ for k, v := range snapshot.View().Options().ConvenienceAnalyzers {
+ analyzers[k] = v
+ }
+ // If we had type errors, only run type error analyzers.
+ if hadTypeErrors {
+ for k, v := range snapshot.View().Options().TypeErrorAnalyzers {
+ analyzers[k] = v
+ }
+ return analyzers
+ }
+ for k, v := range snapshot.View().Options().DefaultAnalyzers {
+ analyzers[k] = v
+ }
+ for k, v := range snapshot.View().Options().StaticcheckAnalyzers {
+ analyzers[k] = v
+ }
+ return analyzers
+}
+
+func FileDiagnostics(ctx context.Context, snapshot Snapshot, uri span.URI) (VersionedFileIdentity, []*Diagnostic, error) {
+ fh, err := snapshot.GetVersionedFile(ctx, uri)
+ if err != nil {
+ return VersionedFileIdentity{}, nil, err
+ }
+ pkg, _, err := GetParsedFile(ctx, snapshot, fh, NarrowestPackage)
+ if err != nil {
+ return VersionedFileIdentity{}, nil, err
+ }
+ reports, _, err := Diagnostics(ctx, snapshot, pkg, true)
+ if err != nil {
+ return VersionedFileIdentity{}, nil, err
+ }
+ diagnostics, ok := reports[fh.VersionedFileIdentity()]
+ if !ok {
+ return VersionedFileIdentity{}, nil, errors.Errorf("no diagnostics for %s", uri)
+ }
+ return fh.VersionedFileIdentity(), diagnostics, nil
+}
+
+type diagnosticSet struct {
+ listErrors, parseErrors, typeErrors []*Diagnostic
+}
+
+func diagnostics(ctx context.Context, snapshot Snapshot, reports map[VersionedFileIdentity][]*Diagnostic, pkg Package, hasMissingDeps bool) (bool, bool, error) {
+ ctx, done := event.Start(ctx, "source.diagnostics", tag.Package.Of(pkg.ID()))
+ _ = ctx // circumvent SA4006
+ defer done()
+
+ diagSets := make(map[span.URI]*diagnosticSet)
+ for _, e := range pkg.GetErrors() {
+ diag := &Diagnostic{
+ Message: e.Message,
+ Range: e.Range,
+ Severity: protocol.SeverityError,
+ Related: e.Related,
+ }
+ set, ok := diagSets[e.URI]
+ if !ok {
+ set = &diagnosticSet{}
+ diagSets[e.URI] = set
+ }
+ switch e.Kind {
+ case ParseError:
+ set.parseErrors = append(set.parseErrors, diag)
+ diag.Source = "syntax"
+ case TypeError:
+ set.typeErrors = append(set.typeErrors, diag)
+ diag.Source = "compiler"
+ case ListError:
+ set.listErrors = append(set.listErrors, diag)
+ diag.Source = "go list"
+ }
+ }
+ var nonEmptyDiagnostics, hasTypeErrors bool // track if we actually send non-empty diagnostics
+ for uri, set := range diagSets {
+ // Don't report type errors if there are parse errors or list errors.
+ diags := set.typeErrors
+ if len(set.parseErrors) > 0 {
+ diags, nonEmptyDiagnostics = set.parseErrors, true
+ } else if len(set.listErrors) > 0 {
+ // Only show list errors if the package has missing dependencies.
+ if hasMissingDeps {
+ diags, nonEmptyDiagnostics = set.listErrors, true
+ }
+ } else if len(set.typeErrors) > 0 {
+ hasTypeErrors = true
+ }
+ if err := addReports(snapshot, reports, uri, diags...); err != nil {
+ return false, false, err
+ }
+ }
+ return nonEmptyDiagnostics, hasTypeErrors, nil
+}
+
+func analyses(ctx context.Context, snapshot Snapshot, reports map[VersionedFileIdentity][]*Diagnostic, pkg Package, analyses map[string]Analyzer) error {
+ var analyzers []*analysis.Analyzer
+ for _, a := range analyses {
+ if !a.IsEnabled(snapshot.View()) {
+ continue
+ }
+ analyzers = append(analyzers, a.Analyzer)
+ }
+ analysisErrors, err := snapshot.Analyze(ctx, pkg.ID(), analyzers...)
+ if err != nil {
+ return err
+ }
+
+ // Report diagnostics and errors from root analyzers.
+ for _, e := range analysisErrors {
+ // If the diagnostic comes from a "convenience" analyzer, it is not
+ // meant to provide diagnostics, but rather only suggested fixes.
+ // Skip these types of errors in diagnostics; we will use their
+ // suggested fixes when providing code actions.
+ if isConvenienceAnalyzer(e.Category) {
+ continue
+ }
+ // This is a bit of a hack, but clients > 3.15 will be able to grey out unnecessary code.
+ // If we are deleting code as part of all of our suggested fixes, assume that this is dead code.
+ // TODO(golang/go#34508): Return these codes from the diagnostics themselves.
+ var tags []protocol.DiagnosticTag
+ if onlyDeletions(e.SuggestedFixes) {
+ tags = append(tags, protocol.Unnecessary)
+ }
+ if err := addReports(snapshot, reports, e.URI, &Diagnostic{
+ Range: e.Range,
+ Message: e.Message,
+ Source: e.Category,
+ Severity: protocol.SeverityWarning,
+ Tags: tags,
+ Related: e.Related,
+ }); err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+func clearReports(snapshot Snapshot, reports map[VersionedFileIdentity][]*Diagnostic, uri span.URI) {
+ fh := snapshot.FindFile(uri)
+ if fh == nil {
+ return
+ }
+ reports[fh.VersionedFileIdentity()] = []*Diagnostic{}
+}
+
+func addReports(snapshot Snapshot, reports map[VersionedFileIdentity][]*Diagnostic, uri span.URI, diagnostics ...*Diagnostic) error {
+ fh := snapshot.FindFile(uri)
+ if fh == nil {
+ return nil
+ }
+ existingDiagnostics, ok := reports[fh.VersionedFileIdentity()]
+ if !ok {
+ return fmt.Errorf("diagnostics for unexpected file %s", uri)
+ }
+ if len(diagnostics) == 1 {
+ d1 := diagnostics[0]
+ if _, ok := snapshot.View().Options().TypeErrorAnalyzers[d1.Source]; ok {
+ for i, d2 := range existingDiagnostics {
+ if r := protocol.CompareRange(d1.Range, d2.Range); r != 0 {
+ continue
+ }
+ if d1.Message != d2.Message {
+ continue
+ }
+ reports[fh.VersionedFileIdentity()][i].Tags = append(reports[fh.VersionedFileIdentity()][i].Tags, d1.Tags...)
+ }
+ return nil
+ }
+ }
+ reports[fh.VersionedFileIdentity()] = append(reports[fh.VersionedFileIdentity()], diagnostics...)
+ return nil
+}
+
+// onlyDeletions returns true if all of the suggested fixes are deletions.
+func onlyDeletions(fixes []SuggestedFix) bool {
+ for _, fix := range fixes {
+ for _, edits := range fix.Edits {
+ for _, edit := range edits {
+ if edit.NewText != "" {
+ return false
+ }
+ if protocol.ComparePosition(edit.Range.Start, edit.Range.End) == 0 {
+ return false
+ }
+ }
+ }
+ }
+ return len(fixes) > 0
+}
+
+// hasUndeclaredErrors returns true if a package has a type error
+// about an undeclared symbol.
+func hasUndeclaredErrors(pkg Package) bool {
+ for _, err := range pkg.GetErrors() {
+ if err.Kind != TypeError {
+ continue
+ }
+ if strings.Contains(err.Message, "undeclared name:") {
+ return true
+ }
+ }
+ return false
+}
+
+func isConvenienceAnalyzer(category string) bool {
+ for _, a := range DefaultOptions().ConvenienceAnalyzers {
+ if category == a.Analyzer.Name {
+ return true
+ }
+ }
+ return false
+}