// style command. The optional args specify the analyzers to describe.
// Help calls log.Fatal if no such analyzer exists.
func Help(progname string, analyzers []*analysis.Analyzer, args []string) {
	// No args: show summary of all analyzers.
	if len(args) == 0 {
		fmt.Println(strings.Replace(help, "PROGNAME", progname, -1))
		fmt.Println("Registered analyzers:")
		fmt.Println()
		sort.Slice(analyzers, func(i, j int) bool {

	// TODO(adonovan): clarify the contract.

	// Print the tool version so the build system can track changes.
	// Formats:
	//   $progname version devel ... buildID=...
	//   $progname version go1.9.1
	progname, err := os.Executable()
	if err != nil {
		return err
	}
	f, err := os.Open(progname)
	if err != nil {
		log.Fatal(err)
	}
	h := sha256.New()
	if _, err := io.Copy(h, f); err != nil {
		log.Fatal(err)

//	foo.cfg         perform separate modular analyze on the single
//	                unit described by a JSON config file foo.cfg.
func Main(analyzers ...*analysis.Analyzer) {
	progname := filepath.Base(os.Args[0])
	log.SetFlags(0)
	log.SetPrefix(progname + ": ")

	if err := analysis.Validate(analyzers); err != nil {
		log.Fatal(err)
	}

	flag.Usage = func() {

}

func testTraceProg(t *testing.T, progName string, extra func(t *testing.T, trace, stderr []byte, stress bool)) {
	testenv.MustHaveGoRun(t)

	// Check if we're on a builder.
	onBuilder := testenv.Builder() != ""
	onOldBuilder := !strings.Contains(testenv.Builder(), "gotip") && !strings.Contains(testenv.Builder(), "go1")

	testPath := filepath.Join("./testdata/testprog", progName)
	testName := progName