tr := NewReader(&buf)

	names := make([]string, 0, len(fsys))
	for name := range fsys {
		names = append(names, name)
	}
	sort.Strings(names)

	entriesLeft := len(fsys)
	for _, name := range names {
		entriesLeft--

		entryInfo, err := fsys.Stat(name)
		if err != nil {
			t.Fatalf("getting entry info error: %v", err)
		}
		hdr, err := tr.Next()
		if err == io.EOF {