How to convert a ByteArray to a ShortArray in Kotlin?

Question

If I have a well-formed ByteArray (say, byteArrayOf(12, 0, 24, 0)), what is the easiest way to convert this into a ShortArray?

For simplicity's sake, assume little-endian unless endianness handling is easy too.

Resultant ShortArray should look like (12, 24).

Answer 1

You can process the ByteArray as a list with .chunked(), though you have to manually convert the two bytes into a Short:

val bytes = byteArrayOf(12, 0, 24, 0)
val shorts = bytes
    .asList()
    .chunked(2)
    .map { (l, h) -> (l.toInt() + h.shl(8)).toShort() }
    .toShortArray()

Answer 2

I'm not certain why, but it appears that Kotlin treats bytes as if they are signed and the above answer work only when the first byte of each pair is < 127.

For example (editing the above to return correct answers):

    val byteArray = byteArrayOf(211.toByte(), 0, 24, 0)
    val shortArray = ShortArray(byteArray.size / 2) {
        (byteArray[it * 2].toUByte().toInt() + (byteArray[(it * 2) + 1].toInt() shl 8)).toShort()
    }
    println(shortArray.toList()) // [211, 24]

Using the above code with the same values returns incorrect information as [-45, 24]