buf.WriteRune(r)
		}
	}
}

// From Issue 5154.
func BenchmarkBufferNotEmptyWriteRead(b *testing.B) {
	buf := make([]byte, 1024)
	for i := 0; i < b.N; i++ {
		var b Buffer
		b.Write(buf[0:1])
		for i := 0; i < 5<<10; i++ {
			b.Write(buf)
			b.Read(buf)
		}
	}
}

// Check that we don't compact too often. From Issue 5154.
func BenchmarkBufferFullSmallReads(b *testing.B) {

		if !validPAXRecord(k, v) {
			return FormatUnknown, nil, headerError{fmt.Sprintf("invalid PAX record: %q", k+" = "+v)}
		}
	}

	// TODO(dsnet): Re-enable this when adding sparse support.
	// See https://golang.org/issue/22735
	/*
		// Check sparse files.
		if len(h.SparseHoles) > 0 || h.Typeflag == TypeGNUSparse {
			if isHeaderOnlyType(h.Typeflag) {
				return FormatUnknown, nil, headerError{"header-only type cannot be sparse"}

To work around this issue without adjusting kernel settings, transparent huge
pages can be disabled for Go memory with the
[`disablethp` setting](/pkg/runtime#hdr-Environment_Variable).
This behavior was backported to Go 1.21.1, but the setting is only available
starting with Go 1.21.6.
This setting may be removed in a future release, and users impacted by this issue

		}
	}

	if got, want := f0.UncompressedSize64, uint64(size)+uint64(len(end)); got != want {
		t.Errorf("UncompressedSize64 %#x, want %#x", got, want)
	}

	return buf
}

// Issue 9857
func testZip64DirectoryRecordLength(buf *rleBuffer, t *testing.T) {
	if !suffixIsZip64(t, buf) {
		t.Fatal("not a zip64")
	}
}

func testValidHeader(h *FileHeader, t *testing.T) {
	var buf bytes.Buffer

func Repeat(b []byte, count int) []byte {
	if count == 0 {
		return []byte{}
	}

	// Since we cannot return an error on overflow,
	// we should panic if the repeat will generate an overflow.
	// See golang.org/issue/16237.
	if count < 0 {
		panic("bytes: negative Repeat count")
	}
	if len(b) >= maxInt/count {
		panic("bytes: Repeat output length overflow")
	}
	n := len(b) * count

	if len(b) == 0 {

			// then it is impossible to distinguish between a valid GNU file
			// and an invalid pre-Go1.8 file.
			//
			// See https://golang.org/issues/12594
			// See https://golang.org/issues/21005
			if p2.err != nil {
				hdr.AccessTime, hdr.ChangeTime = time.Time{}, time.Time{}
				ustar := tr.blk.toUSTAR()
				if s := p.parseString(ustar.prefix()); isASCII(s) {
					prefix = s

	if w.last != nil && !w.last.closed {
		if err := w.last.close(); err != nil {
			return err
		}
	}
	if len(w.dir) > 0 && w.dir[len(w.dir)-1].FileHeader == fh {
		// See https://golang.org/issue/11144 confusion.
		return errors.New("archive/zip: invalid duplicate FileHeader")
	}
	return nil
}

// CreateHeader adds a file to the zip archive using the provided [FileHeader]

	h, err := FileInfoHeader(fi, "")
	if err != nil {
		t.Fatalf("FileInfoHeader: %v", err)
	}
	if g, e := h.Name, "testdata/"; g != e {
		t.Errorf("Name = %q; want %q", g, e)
	}
	// Ignoring c_ISGID for golang.org/issue/4867
	if g, e := h.Mode&^c_ISGID, int64(fi.Mode().Perm()); g != e {
		t.Errorf("Mode = %#o; want %#o", g, e)
	}
	if g, e := h.Size, int64(0); g != e {
		t.Errorf("Size = %v; want %v", g, e)
	}

				Gname:    "dsnet",
				ModTime:  time.Unix(0, 0),
				Format:   FormatGNU,
			}, nil},
			testClose{nil},
		},
		// TODO(dsnet): Re-enable this test when adding sparse support.
		// See https://golang.org/issue/22735
		/*
			}, {
				file: "testdata/gnu-nil-sparse-data.tar",
				tests: []testFnc{
					testHeader{Header{
						Typeflag:    TypeGNUSparse,
						Name:        "sparse.db",
						Size:        1000,

	}
	// TODO: ReleaseTags (need to load default)
	key := dir

	// explicit on GOOS and GOARCH as global cache will use "all" cached packages for
	// an indirect imported package. See https://github.com/golang/go/issues/21181
	// for more detail.
	tags = append(tags, context.GOOS, context.GOARCH)
	sort.Strings(tags)

	for _, tag := range tags {
		if ctags[tag] {
			key += "," + tag
			ctags[tag] = false
		}
	}