var (
	noRune = []rune{}
	noNext = []uint32{mergeFailed}
)

func mergeRuneSets(leftRunes, rightRunes *[]rune, leftPC, rightPC uint32) ([]rune, []uint32) {
	leftLen := len(*leftRunes)
	rightLen := len(*rightRunes)
	if leftLen&0x1 != 0 || rightLen&0x1 != 0 {
		panic("mergeRuneSets odd length []rune")
	}
	var (
		lx, rx int
	)
	merged := make([]rune, 0)
	next := make([]uint32, 0)

		[]rune{69, 74, 60, 65},
		[]rune{66, 67},
		[]rune{},
		[]uint32{mergeFailed},
		1, 2,
	},
}

func TestMergeRuneSet(t *testing.T) {
	for ix, test := range runeMergeTests {
		merged, next := mergeRuneSets(&test.left, &test.right, test.leftPC, test.rightPC)
		if !slices.Equal(merged, test.merged) {
			t.Errorf("mergeRuneSet :%d (%v, %v) merged\n have\n%v\nwant\n%v", ix, test.left, test.right, merged, test.merged)
		}