func RunWithStdin(ctx context.Context, dir string, stdin io.Reader, cmdline ...any) ([]byte, error) {
	if dir != "" {
		muIface, ok := dirLock.Load(dir)
		if !ok {
			muIface, _ = dirLock.LoadOrStore(dir, new(sync.Mutex))
		}
		mu := muIface.(*sync.Mutex)
		mu.Lock()
		defer mu.Unlock()
	}

	cmd := str.StringList(cmdline...)
	if os.Getenv("TESTGOVCS") == "panic" {

func (s *Server) HandleScript(scriptRelPath string, logger *log.Logger, f func(http.Handler)) error {
	ri, ok := s.scriptCache.Load(scriptRelPath)
	if !ok {
		ri, _ = s.scriptCache.LoadOrStore(scriptRelPath, new(scriptResult))
	}
	r := ri.(*scriptResult)

	relDir := strings.TrimSuffix(scriptRelPath, filepath.Ext(scriptRelPath))
	workDir := filepath.Join(s.workDir, relDir)

	// real func (f) to be ready and then calls it. This indirect
	// func is only used for recursive types.
	var (
		wg sync.WaitGroup
		f  encoderFunc
	)
	wg.Add(1)
	fi, loaded := encoderCache.LoadOrStore(t, encoderFunc(func(e *encodeState, v reflect.Value, opts encOpts) {
		wg.Wait()
		f(e, v, opts)
	}))
	if loaded {
		return fi.(encoderFunc)
	}

		} else {
			str = "rpc.Register: type " + sname + " has no exported methods of suitable type"
		}
		log.Print(str)
		return errors.New(str)
	}

	if _, dup := server.serviceMap.LoadOrStore(sname, s); dup {
		return errors.New("rpc: service already defined: " + sname)
	}
	return nil
}

// suitableMethods returns suitable Rpc methods of typ. It will log
// errors if logErr is true.

		}
		if f.Module != nil {
			summary.module = f.Module.Mod
			summary.deprecated = f.Module.Deprecated
		}
		if f.Go != nil {
			rawGoVersion.LoadOrStore(m, f.Go.Version)
			summary.goVersion = f.Go.Version
			summary.pruning = pruningForGoVersion(f.Go.Version)
		} else {
			summary.pruning = unpruned
		}
		if f.Toolchain != nil {

			client.cancelFn(context.DeadlineExceeded)
			return nil, context.DeadlineExceeded
		}
	}
	for {
		// Handle the extremely unlikely scenario that we wrapped.
		if _, loaded := c.outgoing.LoadOrStore(client.MuxID, client); client.MuxID != 0 && !loaded {
			if debugReqs {
				_, found := c.outgoing.Load(client.MuxID)

// which to run the command.
func helperCommandContext(t *testing.T, ctx context.Context, name string, args ...string) (cmd *exec.Cmd) {
	helperCommandUsed.LoadOrStore(name, true)

	t.Helper()
	testenv.MustHaveExec(t)

	cs := append([]string{name}, args...)
	if ctx != nil {
		cmd = exec.CommandContext(ctx, exePath(t), cs...)
	} else {