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/lsp/protocol"
 	"golang.org/x/tools/internal/lsp/telemetry"
 	"golang.org/x/tools/internal/span"
 	"golang.org/x/tools/internal/telemetry/log"
 	"golang.org/x/tools/internal/telemetry/trace"
 	errors "golang.org/x/xerrors"
 )

 type Diagnostic struct {
 	Range    protocol.Range
 	Message  string
 	Source   string
 	Severity protocol.DiagnosticSeverity
 	Tags     []protocol.DiagnosticTag

 	SuggestedFixes []SuggestedFix
 	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 FileDiagnostics(ctx context.Context, snapshot Snapshot, fh FileHandle, withAnalysis bool, disabledAnalyses map[string]struct{}) (map[FileIdentity][]Diagnostic, string, error) {
 	if fh.Identity().Kind != Go {
 		return nil, "", errors.Errorf("unexpected file type: %q", fh.Identity().URI.Filename)
 	}
 	phs, err := snapshot.PackageHandles(ctx, fh)
 	if err != nil {
 		return nil, "", err
 	}
 	ph, err := WidestCheckPackageHandle(phs)
 	if err != nil {
 		return nil, "", err
 	}
 	// If we are missing dependencies, it may because the user's workspace is
 	// not correctly configured. Report errors, if possible.
 	var warningMsg string
 	if len(ph.MissingDependencies()) > 0 {
 		if warningMsg, err = checkCommonErrors(ctx, snapshot.View()); err != nil {
 			log.Error(ctx, "error checking common errors", err, telemetry.File.Of(fh.Identity().URI))
 		}
 	}
 	reports, msg, err := PackageDiagnostics(ctx, snapshot, ph, withAnalysis, disabledAnalyses)
 	if warningMsg == "" {
 		warningMsg = msg
 	}
 	return reports, warningMsg, err
 }

 func PackageDiagnostics(ctx context.Context, snapshot Snapshot, ph PackageHandle, withAnalysis bool, disabledAnalyses map[string]struct{}) (map[FileIdentity][]Diagnostic, string, error) {
 	pkg, err := ph.Check(ctx)
 	if err != nil {
 		return nil, "", err
 	}
 	var warningMsg string
 	// 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) {
 		fh := pkg.CompiledGoFiles()[0].File()
 		if warningMsg, err = checkCommonErrors(ctx, snapshot.View()); err != nil {
 			log.Error(ctx, "error checking common errors", err, telemetry.File.Of(fh.Identity().URI))
 		}
 	}
 	// Prepare the reports we will send for the files in this package.
 	reports := make(map[FileIdentity][]Diagnostic)
 	for _, fh := range pkg.CompiledGoFiles() {
 		clearReports(snapshot, reports, fh.File().Identity())
 	}
 	// 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 _, ph := range pkg.CompiledGoFiles() {
 				if snapshot.View().Session().IsOpen(ph.File().Identity().URI) {
 					e.URI = ph.File().Identity().URI
 				}
 			}
 		}
 		fh, err := snapshot.GetFile(e.URI)
 		if err != nil {
 			return nil, warningMsg, err
 		}
 		clearReports(snapshot, reports, fh.Identity())
 	}
 	// Run diagnostics for the package that this URI belongs to.
 	hadDiagnostics, err := diagnostics(ctx, snapshot, reports, pkg)
 	if err != nil {
 		return nil, warningMsg, err
 	}
 	if !hadDiagnostics && withAnalysis {
 		// If we don't have any list, parse, or type errors, run analyses.
 		if err := analyses(ctx, snapshot, reports, ph, disabledAnalyses); err != nil {
 			// Exit early if the context has been canceled.
 			if err == context.Canceled {
 				return nil, warningMsg, err
 			}
 			log.Error(ctx, "failed to run analyses", err, telemetry.Package.Of(ph.ID()))
 		}
 	}
 	// Updates to the diagnostics for this package may need to be propagated.
 	reverseDeps, err := snapshot.GetReverseDependencies(ctx, pkg.ID())
 	if err != nil {
 		if err == context.Canceled {
 			return nil, warningMsg, err
 		}
 		log.Error(ctx, "no reverse dependencies", err)
 		return reports, warningMsg, nil
 	}
 	for _, ph := range reverseDeps {
 		pkg, err := ph.Check(ctx)
 		if err != nil {
 			return nil, warningMsg, err
 		}
 		for _, fh := range pkg.CompiledGoFiles() {
 			clearReports(snapshot, reports, fh.File().Identity())
 		}
 		diagnostics(ctx, snapshot, reports, pkg)
 	}
 	return reports, warningMsg, nil
 }

 type diagnosticSet struct {
 	listErrors, parseErrors, typeErrors []*Diagnostic
 }

 func diagnostics(ctx context.Context, snapshot Snapshot, reports map[FileIdentity][]Diagnostic, pkg Package) (bool, error) {
 	ctx, done := trace.StartSpan(ctx, "source.diagnostics", telemetry.Package.Of(pkg.ID()))
 	_ = ctx // circumvent SA4006
 	defer done()

 	diagSets := make(map[FileIdentity]*diagnosticSet)
 	for _, e := range pkg.GetErrors() {
 		diag := &Diagnostic{
 			Message:  e.Message,
 			Range:    e.Range,
 			Severity: protocol.SeverityError,
 		}
 		fh, err := snapshot.GetFile(e.URI)
 		if err != nil {
 			return false, err
 		}
 		set, ok := diagSets[fh.Identity()]
 		if !ok {
 			set = &diagnosticSet{}
 			diagSets[fh.Identity()] = 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 bool // track if we actually send non-empty diagnostics
 	for fileID, 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 = set.parseErrors
 		} else if len(set.listErrors) > 0 {
 			diags = set.listErrors
 		}
 		if len(diags) > 0 {
 			nonEmptyDiagnostics = true
 		}
 		addReports(ctx, snapshot, reports, fileID, diags...)
 	}
 	return nonEmptyDiagnostics, nil
 }

 func analyses(ctx context.Context, snapshot Snapshot, reports map[FileIdentity][]Diagnostic, ph PackageHandle, disabledAnalyses map[string]struct{}) error {
 	var analyzers []*analysis.Analyzer
 	for _, a := range snapshot.View().Options().Analyzers {
 		if _, ok := disabledAnalyses[a.Name]; ok {
 			continue
 		}
 		analyzers = append(analyzers, a)
 	}

 	diagnostics, err := snapshot.Analyze(ctx, ph.ID(), analyzers)
 	if err != nil {
 		return err
 	}

 	// Report diagnostics and errors from root analyzers.
 	for _, e := range diagnostics {
 		// 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)
 		}
 		fh, err := snapshot.GetFile(e.URI)
 		if err != nil {
 			return err
 		}
 		addReports(ctx, snapshot, reports, fh.Identity(), &Diagnostic{
 			Range:          e.Range,
 			Message:        e.Message,
 			Source:         e.Category,
 			Severity:       protocol.SeverityWarning,
 			Tags:           tags,
 			SuggestedFixes: e.SuggestedFixes,
 			Related:        e.Related,
 		})
 	}
 	return nil
 }

 func clearReports(snapshot Snapshot, reports map[FileIdentity][]Diagnostic, fileID FileIdentity) {
 	if snapshot.View().Ignore(fileID.URI) {
 		return
 	}
 	reports[fileID] = []Diagnostic{}
 }

 func addReports(ctx context.Context, snapshot Snapshot, reports map[FileIdentity][]Diagnostic, fileID FileIdentity, diagnostics ...*Diagnostic) error {
 	if snapshot.View().Ignore(fileID.URI) {
 		return nil
 	}
 	if _, ok := reports[fileID]; !ok {
 		return errors.Errorf("diagnostics for unexpected file %s", fileID.URI)
 	}
 	for _, diag := range diagnostics {
 		if diag == nil {
 			continue
 		}
 		reports[fileID] = append(reports[fileID], *diag)
 	}
 	return nil
 }

 func singleDiagnostic(fileID FileIdentity, format string, a ...interface{}) map[FileIdentity][]Diagnostic {
 	return map[FileIdentity][]Diagnostic{
 		fileID: []Diagnostic{
 			{
 				Source:   "gopls",
 				Range:    protocol.Range{},
 				Message:  fmt.Sprintf(format, a...),
 				Severity: protocol.SeverityError,
 			},
 		},
 	}
 }

 // 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 true
 }

 // 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
 }
	// 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/lsp/protocol"
	"golang.org/x/tools/internal/lsp/telemetry"
	"golang.org/x/tools/internal/span"
	"golang.org/x/tools/internal/telemetry/log"
	"golang.org/x/tools/internal/telemetry/trace"
	errors "golang.org/x/xerrors"
	)

	type Diagnostic struct {
	Range protocol.Range
	Message string
	Source string
	Severity protocol.DiagnosticSeverity
	Tags []protocol.DiagnosticTag

	SuggestedFixes []SuggestedFix
	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 FileDiagnostics(ctx context.Context, snapshot Snapshot, fh FileHandle, withAnalysis bool, disabledAnalyses map[string]struct{}) (map[FileIdentity][]Diagnostic, string, error) {
	if fh.Identity().Kind != Go {
	return nil, "", errors.Errorf("unexpected file type: %q", fh.Identity().URI.Filename)
	}
	phs, err := snapshot.PackageHandles(ctx, fh)
	if err != nil {
	return nil, "", err
	}
	ph, err := WidestCheckPackageHandle(phs)
	if err != nil {
	return nil, "", err
	}
	// If we are missing dependencies, it may because the user's workspace is
	// not correctly configured. Report errors, if possible.
	var warningMsg string
	if len(ph.MissingDependencies()) > 0 {
	if warningMsg, err = checkCommonErrors(ctx, snapshot.View()); err != nil {
	log.Error(ctx, "error checking common errors", err, telemetry.File.Of(fh.Identity().URI))
	}
	}
	reports, msg, err := PackageDiagnostics(ctx, snapshot, ph, withAnalysis, disabledAnalyses)
	if warningMsg == "" {
	warningMsg = msg
	}
	return reports, warningMsg, err
	}

	func PackageDiagnostics(ctx context.Context, snapshot Snapshot, ph PackageHandle, withAnalysis bool, disabledAnalyses map[string]struct{}) (map[FileIdentity][]Diagnostic, string, error) {
	pkg, err := ph.Check(ctx)
	if err != nil {
	return nil, "", err
	}
	var warningMsg string
	// 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) {
	fh := pkg.CompiledGoFiles()[0].File()
	if warningMsg, err = checkCommonErrors(ctx, snapshot.View()); err != nil {
	log.Error(ctx, "error checking common errors", err, telemetry.File.Of(fh.Identity().URI))
	}
	}
	// Prepare the reports we will send for the files in this package.
	reports := make(map[FileIdentity][]Diagnostic)
	for _, fh := range pkg.CompiledGoFiles() {
	clearReports(snapshot, reports, fh.File().Identity())
	}
	// 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 _, ph := range pkg.CompiledGoFiles() {
	if snapshot.View().Session().IsOpen(ph.File().Identity().URI) {
	e.URI = ph.File().Identity().URI
	}
	}
	}
	fh, err := snapshot.GetFile(e.URI)
	if err != nil {
	return nil, warningMsg, err
	}
	clearReports(snapshot, reports, fh.Identity())
	}
	// Run diagnostics for the package that this URI belongs to.
	hadDiagnostics, err := diagnostics(ctx, snapshot, reports, pkg)
	if err != nil {
	return nil, warningMsg, err
	}
	if !hadDiagnostics && withAnalysis {
	// If we don't have any list, parse, or type errors, run analyses.
	if err := analyses(ctx, snapshot, reports, ph, disabledAnalyses); err != nil {
	// Exit early if the context has been canceled.
	if err == context.Canceled {
	return nil, warningMsg, err
	}
	log.Error(ctx, "failed to run analyses", err, telemetry.Package.Of(ph.ID()))
	}
	}
	// Updates to the diagnostics for this package may need to be propagated.
	reverseDeps, err := snapshot.GetReverseDependencies(ctx, pkg.ID())
	if err != nil {
	if err == context.Canceled {
	return nil, warningMsg, err
	}
	log.Error(ctx, "no reverse dependencies", err)
	return reports, warningMsg, nil
	}
	for _, ph := range reverseDeps {
	pkg, err := ph.Check(ctx)
	if err != nil {
	return nil, warningMsg, err
	}
	for _, fh := range pkg.CompiledGoFiles() {
	clearReports(snapshot, reports, fh.File().Identity())
	}
	diagnostics(ctx, snapshot, reports, pkg)
	}
	return reports, warningMsg, nil
	}

	type diagnosticSet struct {
	listErrors, parseErrors, typeErrors []*Diagnostic
	}

	func diagnostics(ctx context.Context, snapshot Snapshot, reports map[FileIdentity][]Diagnostic, pkg Package) (bool, error) {
	ctx, done := trace.StartSpan(ctx, "source.diagnostics", telemetry.Package.Of(pkg.ID()))
	_ = ctx // circumvent SA4006
	defer done()

	diagSets := make(map[FileIdentity]*diagnosticSet)
	for _, e := range pkg.GetErrors() {
	diag := &Diagnostic{
	Message: e.Message,
	Range: e.Range,
	Severity: protocol.SeverityError,
	}
	fh, err := snapshot.GetFile(e.URI)
	if err != nil {
	return false, err
	}
	set, ok := diagSets[fh.Identity()]
	if !ok {
	set = &diagnosticSet{}
	diagSets[fh.Identity()] = 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 bool // track if we actually send non-empty diagnostics
	for fileID, 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 = set.parseErrors
	} else if len(set.listErrors) > 0 {
	diags = set.listErrors
	}
	if len(diags) > 0 {
	nonEmptyDiagnostics = true
	}
	addReports(ctx, snapshot, reports, fileID, diags...)
	}
	return nonEmptyDiagnostics, nil
	}

	func analyses(ctx context.Context, snapshot Snapshot, reports map[FileIdentity][]Diagnostic, ph PackageHandle, disabledAnalyses map[string]struct{}) error {
	var analyzers []*analysis.Analyzer
	for _, a := range snapshot.View().Options().Analyzers {
	if _, ok := disabledAnalyses[a.Name]; ok {
	continue
	}
	analyzers = append(analyzers, a)
	}

	diagnostics, err := snapshot.Analyze(ctx, ph.ID(), analyzers)
	if err != nil {
	return err
	}

	// Report diagnostics and errors from root analyzers.
	for _, e := range diagnostics {
	// 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)
	}
	fh, err := snapshot.GetFile(e.URI)
	if err != nil {
	return err
	}
	addReports(ctx, snapshot, reports, fh.Identity(), &Diagnostic{
	Range: e.Range,
	Message: e.Message,
	Source: e.Category,
	Severity: protocol.SeverityWarning,
	Tags: tags,
	SuggestedFixes: e.SuggestedFixes,
	Related: e.Related,
	})
	}
	return nil
	}

	func clearReports(snapshot Snapshot, reports map[FileIdentity][]Diagnostic, fileID FileIdentity) {
	if snapshot.View().Ignore(fileID.URI) {
	return
	}
	reports[fileID] = []Diagnostic{}
	}

	func addReports(ctx context.Context, snapshot Snapshot, reports map[FileIdentity][]Diagnostic, fileID FileIdentity, diagnostics ...*Diagnostic) error {
	if snapshot.View().Ignore(fileID.URI) {
	return nil
	}
	if _, ok := reports[fileID]; !ok {
	return errors.Errorf("diagnostics for unexpected file %s", fileID.URI)
	}
	for _, diag := range diagnostics {
	if diag == nil {
	continue
	}
	reports[fileID] = append(reports[fileID], *diag)
	}
	return nil
	}

	func singleDiagnostic(fileID FileIdentity, format string, a ...interface{}) map[FileIdentity][]Diagnostic {
	return map[FileIdentity][]Diagnostic{
	fileID: []Diagnostic{
	{
	Source: "gopls",
	Range: protocol.Range{},
	Message: fmt.Sprintf(format, a...),
	Severity: protocol.SeverityError,
	},
	},
	}
	}

	// 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 true
	}

	// 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
	}