if !bytes.Contains(buf.Bytes(), []byte("PaxHeaders.0")) {
		t.Fatal("Expected at least one PAX header to be written.")
	}

	// xattr bar should always appear before others
	indices := []int{
		bytes.Index(buf.Bytes(), []byte("bar=bar")),
		bytes.Index(buf.Bytes(), []byte("baz=baz")),
		bytes.Index(buf.Bytes(), []byte("foo=foo")),
		bytes.Index(buf.Bytes(), []byte("qux=qux")),
	}

	Mode   fs.FileMode
}

var writeTests = []WriteTest{
	{
		Name:   "foo",
		Data:   []byte("Rabbits, guinea pigs, gophers, marsupial rats, and quolls."),
		Method: Store,
		Mode:   0666,
	},
	{
		Name:   "bar",
		Data:   nil, // large data set in the test
		Method: Deflate,
		Mode:   0644,
	},
	{
		Name:   "setuid",
		Data:   []byte("setuid file"),
		Method: Deflate,
		Mode:   0755 | fs.ModeSetuid,
	},
	{