b.RunParallel(func(pb *testing.PB) {
		var buf bytes.Buffer
		for pb.Next() {
			runOnce(&buf)
		}
	})
}

func writeTestsToFS(tests []WriteTest) fs.FS {
	fsys := fstest.MapFS{}
	for _, wt := range tests {
		fsys[wt.Name] = &fstest.MapFile{
			Data: wt.Data,
			Mode: wt.Mode,
		}
	}
	return fsys
}

func TestWriterAddFS(t *testing.T) {
	buf := new(bytes.Buffer)
	w := NewWriter(buf)

package tar

import (
	"bytes"
	"encoding/hex"
	"errors"
	"io"
	"io/fs"
	"maps"
	"os"
	"path"
	"slices"
	"sort"
	"strings"
	"testing"
	"testing/fstest"
	"testing/iotest"
	"time"
)

func bytediff(a, b []byte) string {
	const (
		uniqueA  = "-  "
		uniqueB  = "+  "
		identity = "   "
	)
	var ss []string