if err := os.Chtimes(fn, past, past); err != nil {
		t.Fatal(err)
	}

	info, err := os.Stat(fn)
	if err != nil {
		t.Fatal(err)
	}

	defer func() { *write = false }()
	*write = true

	initParserMode()
	initRewrite()

	const maxWeight = 2 << 20
	var buf, errBuf strings.Builder
	s := newSequencer(maxWeight, &buf, &errBuf)
	s.Add(fileWeight(fn, info), func(r *reporter) error {

	panicOnError  = flag.Bool("panic", false, "panic on first error")
)

var (
	fset       = token.NewFileSet()
	errorCount = 0
	sequential = false
	parserMode parser.Mode
)

func initParserMode() {
	if *allErrors {
		parserMode |= parser.AllErrors
	}
	if *printAST {
		sequential = true
	}
	if *printTrace {
		parserMode |= parser.Trace
		sequential = true
	}

		case "-s":
			*simplifyAST = true
		case "-stdin":
			// fake flag - pretend input is from stdin
			info = nil
		default:
			t.Errorf("unrecognized flag name: %s", name)
		}
	}

	initParserMode()
	initRewrite()

	const maxWeight = 2 << 20
	var buf, errBuf bytes.Buffer
	s := newSequencer(maxWeight, &buf, &errBuf)
	s.Add(fileWeight(in, info), func(r *reporter) error {
		return processFile(in, info, nil, r)

var (
	rewrite    func(*token.FileSet, *ast.File) *ast.File
	parserMode parser.Mode
)

func usage() {
	fmt.Fprintf(os.Stderr, "usage: gofmt [flags] [path ...]\n")
	flag.PrintDefaults()
}

func initParserMode() {
	parserMode = parser.ParseComments
	if *allErrors {
		parserMode |= parser.AllErrors
	}
	// It's only -r that makes use of go/ast's object resolution,
	// so avoid the unnecessary work if the flag isn't used.