gopls/internal/lsp/source: eliminate Snapshot.FileSet

Eliminate remaining uses of the global fileset API.

For golang/go#57987

Change-Id: Ida5a7c556bf48d07a90966aa4f5623e64cc48378
Reviewed-on: https://go-review.googlesource.com/c/tools/+/468215
TryBot-Result: Gopher Robot <[email protected]>
gopls-CI: kokoro <[email protected]>
Run-TryBot: Robert Findley <[email protected]>
Reviewed-by: Alan Donovan <[email protected]>

Author: findleyr

gopls/internal/lsp/cache/check.go

@@ -449,7 +449,7 @@ func doTypeCheck(ctx context.Context, snapshot *snapshot, inputs typeCheckInputs
 	pkg := &syntaxPackage{
 		id:        inputs.id,
 		mode:      inputs.mode,
-		fset:      snapshot.FileSet(), // must match parse call below (snapshot.ParseGo for now)
+		fset:      snapshot.view.fset, // must match parse call below (snapshot.ParseGo for now)
 		types:     types.NewPackage(string(inputs.pkgPath), string(inputs.name)),
 		importMap: new(importMap),
 		typesInfo: &types.Info{

gopls/internal/lsp/cache/parse.go

@@ -64,7 +64,7 @@ func (s *snapshot) ParseGo(ctx context.Context, fh source.FileHandle, mode sourc
 	// cache miss?
 	if !hit {
 		promise, release := s.store.Promise(key, func(ctx context.Context, arg interface{}) interface{} {
-			parsed, err := parseGoImpl(ctx, arg.(*snapshot).FileSet(), fh, mode)
+			parsed, err := parseGoImpl(ctx, arg.(*snapshot).view.fset, fh, mode)
 			return parseGoResult{parsed, err}
 		})
 

gopls/internal/lsp/cache/snapshot.go

@@ -261,10 +261,6 @@ func (s *snapshot) BackgroundContext() context.Context {
 	return s.backgroundCtx
 }
 
-func (s *snapshot) FileSet() *token.FileSet {
-	return s.view.fset
-}
-
 func (s *snapshot) ModFiles() []span.URI {
 	var uris []span.URI
 	for modURI := range s.workspaceModFiles {

gopls/internal/lsp/command.go

@@ -743,7 +743,8 @@ func (c *commandHandler) ListImports(ctx context.Context, args command.URIArg) (
 		if err != nil {
 			return err
 		}
-		for _, group := range astutil.Imports(deps.snapshot.FileSet(), pgf.File) {
+		fset := source.SingletonFileSet(pgf.Tok)
+		for _, group := range astutil.Imports(fset, pgf.File) {
 			for _, imp := range group {
 				if imp.Path == nil {
 					continue

gopls/internal/lsp/source/fix.go

@@ -26,6 +26,9 @@ type (
 	// suggested fixes with their diagnostics, so we have to compute them
 	// separately. Such analyzers should provide a function with a signature of
 	// SuggestedFixFunc.
+	//
+	// The returned FileSet must map all token.Pos found in the suggested text
+	// edits.
 	SuggestedFixFunc  func(ctx context.Context, snapshot Snapshot, fh FileHandle, pRng protocol.Range) (*token.FileSet, *analysis.SuggestedFix, error)
 	singleFileFixFunc func(fset *token.FileSet, start, end token.Pos, src []byte, file *ast.File, pkg *types.Package, info *types.Info) (*analysis.SuggestedFix, error)
 )

gopls/internal/lsp/source/format.go

@@ -33,7 +33,6 @@ func Format(ctx context.Context, snapshot Snapshot, fh FileHandle) ([]protocol.T
 		return nil, fmt.Errorf("can't format %q: file is generated", fh.URI().Filename())
 	}
 
-	fset := snapshot.FileSet()
 	pgf, err := snapshot.ParseGo(ctx, fh, ParseFull)
 	if err != nil {
 		return nil, err
@@ -54,6 +53,7 @@ func Format(ctx context.Context, snapshot Snapshot, fh FileHandle) ([]protocol.T
 	// This should be acceptable for all users, who likely be prompted to rebuild
 	// the LSP server on each Go release.
 	buf := &bytes.Buffer{}
+	fset := SingletonFileSet(pgf.Tok)
 	if err := format.Node(buf, fset, pgf.File); err != nil {
 		return nil, err
 	}

gopls/internal/lsp/source/stub.go

@@ -125,7 +125,7 @@ func stubSuggestedFixFunc(ctx context.Context, snapshot Snapshot, fh FileHandle,
 			NewText: []byte(edit.New),
 		})
 	}
-	return snapshot.FileSet(), // to match snapshot.ParseGo above
+	return SingletonFileSet(parsedConcreteFile.Tok), // edits use parsedConcreteFile.Tok
 		&analysis.SuggestedFix{TextEdits: edits},
 		nil
 }

gopls/internal/lsp/source/types_format.go

@@ -87,7 +87,6 @@ func (s *signature) Params() []string {
 // NewBuiltinSignature returns signature for the builtin object with a given
 // name, if a builtin object with the name exists.
 func NewBuiltinSignature(ctx context.Context, s Snapshot, name string) (*signature, error) {
-	fset := s.FileSet()
 	builtin, err := s.BuiltinFile(ctx)
 	if err != nil {
 		return nil, err
@@ -111,6 +110,7 @@ func NewBuiltinSignature(ctx context.Context, s Snapshot, name string) (*signatu
 			variadic = true
 		}
 	}
+	fset := SingletonFileSet(builtin.Tok)
 	params, _ := formatFieldList(ctx, fset, decl.Type.Params, variadic)
 	results, needResultParens := formatFieldList(ctx, fset, decl.Type.Results, false)
 	d := decl.Doc.Text()

gopls/internal/lsp/source/view.go

@@ -62,14 +62,6 @@ type Snapshot interface {
 	// on behalf of this snapshot.
 	BackgroundContext() context.Context
 
-	// Fileset returns the Fileset used to parse all the Go files in this snapshot.
-	//
-	// If the files are known to belong to a specific Package, use
-	// Package.FileSet instead. (We plan to eliminate the
-	// Snapshot's cache of parsed files, and thus the need for a
-	// snapshot-wide FileSet.)
-	FileSet() *token.FileSet
-
 	// ValidBuildConfiguration returns true if there is some error in the
 	// user's workspace. In particular, if they are both outside of a module
 	// and their GOPATH.