blob: 2632e654cb8a655c39ee07fe0d1fd8cffd4ebf74 [file] [log] [blame]
Leo Repp58b9f112021-11-22 11:57:47 +01001'use strict';
2
3var GetIntrinsic = require('get-intrinsic');
4
5var $TypeError = GetIntrinsic('%TypeError%');
6var $fromCharCode = GetIntrinsic('%String.fromCharCode%');
7
8var isLeadingSurrogate = require('../helpers/isLeadingSurrogate');
9var isTrailingSurrogate = require('../helpers/isTrailingSurrogate');
10
11// https://262.ecma-international.org/11.0/#sec-utf16decodesurrogatepair
12
13module.exports = function UTF16DecodeSurrogatePair(lead, trail) {
14 if (!isLeadingSurrogate(lead) || !isTrailingSurrogate(trail)) {
15 throw new $TypeError('Assertion failed: `lead` must be a leading surrogate char code, and `trail` must be a trailing surrogate char code');
16 }
17 // var cp = (lead - 0xD800) * 0x400 + (trail - 0xDC00) + 0x10000;
18 return $fromCharCode(lead) + $fromCharCode(trail);
19};