// check for omitted fields
	zb0001Len := uint32(18)
	var zb0001Mask uint32 /* 18 bits */
	_ = zb0001Mask
	if z.PartIndices == nil {
		zb0001Len--
		zb0001Mask |= 0x2000
	}
	// variable map header, size zb0001Len
	err = en.WriteMapHeader(zb0001Len)
	if err != nil {
		return
	}
	if zb0001Len == 0 {
		return
	}
	// write "ID"

	{" ", []rune{32}, false},
	{"ABC", []rune{65, 66, 67}, false},
	{"abc", []rune{97, 98, 99}, false},
	{"\u65e5\u672c\u8a9e", []rune{26085, 26412, 35486}, false},
	{"ab\x80c", []rune{97, 98, 0xFFFD, 99}, true},
	{"ab\xc0c", []rune{97, 98, 0xFFFD, 99}, true},
}

func TestRunes(t *testing.T) {
	for _, tt := range RunesTests {
		tin := []byte(tt.in)
		a := Runes(tin)
		if !slices.Equal(a, tt.out) {