}
	fn.add(stmtf("return false"))
	genFile.add(fn)

	// Remove unused imports and variables.
	buf := new(bytes.Buffer)
	fprint(buf, genFile)
	fset := token.NewFileSet()
	file, err := parser.ParseFile(fset, "", buf, parser.ParseComments)
	if err != nil {
		filename := fmt.Sprintf("%s_broken.go", arch.name)
		if err := os.WriteFile(filename, buf.Bytes(), 0644); err != nil {

	// Pass in the overlaid source if we have an overlay for this file.
	src, err := fsys.Open(filename)
	if err != nil {
		return err
	}
	defer src.Close()
	f, err := parser.ParseFile(testFileSet, filename, src, parser.ParseComments|parser.SkipObjectResolution)
	if err != nil {
		return err
	}
	for _, d := range f.Decls {
		n, ok := d.(*ast.FuncDecl)
		if !ok {
			continue
		}

package p

func A(func(any), ...any) {}
func B[T any](T)          {}

func _() {
	A(B, nil // syntax error: missing ',' before newline in argument list
}
`
	fset := token.NewFileSet()
	f, err := parser.ParseFile(fset, pkgName(src), src, 0)
	if err == nil {
		t.Fatal("expected syntax error")
	}

	var conf Config
	conf.Check(f.Name.Name, fset, []*ast.File{f}, nil) // must not panic
}

// at https://go.dev/s/generatedcode.
//
// The syntax tree must have been parsed with the [parser.ParseComments] flag.
// Example:
//
//	f, err := parser.ParseFile(fset, filename, src, parser.ParseComments|parser.PackageClauseOnly)
//	if err != nil { ... }
//	gen := ast.IsGenerated(f)
func IsGenerated(file *File) bool {
	_, ok := generator(file)
	return ok
}

func (p *Package) annotateFile(name string, fd io.Writer) {
	fset := token.NewFileSet()
	content, err := os.ReadFile(name)
	if err != nil {
		log.Fatalf("cover: %s: %s", name, err)
	}
	parsedFile, err := parser.ParseFile(fset, name, content, parser.ParseComments)
	if err != nil {
		log.Fatalf("cover: %s: %s", name, err)
	}

	file := &File{
		fset:    fset,
		name:    name,
		content: content,