main repo

node_modules/es-abstract/2021/UTF16SurrogatePairToCodePoint.js

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+'use strict';
+
+var GetIntrinsic = require('get-intrinsic');
+
+var $TypeError = require('es-errors/type');
+var $fromCharCode = GetIntrinsic('%String.fromCharCode%');
+
+var isLeadingSurrogate = require('../helpers/isLeadingSurrogate');
+var isTrailingSurrogate = require('../helpers/isTrailingSurrogate');
+
+// https://tc39.es/ecma262/2020/#sec-utf16decodesurrogatepair
+
+module.exports = function UTF16SurrogatePairToCodePoint(lead, trail) {
+	if (!isLeadingSurrogate(lead) || !isTrailingSurrogate(trail)) {
+		throw new $TypeError('Assertion failed: `lead` must be a leading surrogate char code, and `trail` must be a trailing surrogate char code');
+	}
+	// var cp = (lead - 0xD800) * 0x400 + (trail - 0xDC00) + 0x10000;
+	return $fromCharCode(lead) + $fromCharCode(trail);
+};