{"\xff\x80\x00\x00\x00\x00\x00\x00\x00", math.MinInt64, true},
		{"\xff\x7f\xff\xff\xff\xff\xff\xff\xff", 0, false},
		{"\xf5\xec\xd1\xc7\x7e\x5f\x26\x48\x81\x9f\x8f\x9b", 0, false},

		// Test base-8 (octal) encoded values.
		{"0000000\x00", 0, true},
		{" \x0000000\x00", 0, true},
		{" \x0000003\x00", 3, true},
		{"00000000227\x00", 0227, true},
		{"032033\x00 ", 032033, true},
		{"320330\x00 ", 0320330, true},

			// files generated by a pre-Go1.8 toolchain. If the generated file
			// happened to have a prefix field that parses as valid
			// atime and ctime fields (e.g., when they are valid octal strings),
			// 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

}

func TestRoundTrip(t *testing.T) {
	data := []byte("some file contents")

	var b bytes.Buffer
	tw := NewWriter(&b)
	hdr := &Header{
		Name:       "file.txt",
		Uid:        1 << 21, // Too big for 8 octal digits
		Size:       int64(len(data)),
		ModTime:    time.Now().Round(time.Second),
		PAXRecords: map[string]string{"uid": "2097152"},
		Format:     FormatPAX,
		Typeflag:   TypeReg,
	}