in src/scala/generator/src/main/scala/EmojiInfoGeneratedView.scala [180:196]
def regexFromCodepointSequences(codePointSequences: Seq[Seq[Int]]) = {
val normalizedCodePointSequences = if (isUCS2) {
codePointSequences.map(codePointSequence => {
codePointSequence.flatMap {
case codePoint if codePoint >= 0x10000 && codePoint < 0x110000 =>
Seq(
((codePoint - 0x10000) >> 10) + 0xd800,
(codePoint & 0x3ff) + 0xdc00
)
case codePoint if codePoint < 0x10000 => Seq(codePoint)
case _ => Nil
}
})
} else codePointSequences
internalRegexFromCodepointSequences(normalizedCodePointSequences)
}