internal/lsp/source/diagnostics.go - tools - Git at Google

 // 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
 }

 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
 }
	// 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
	}

	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
	}