blob: 86927b478ccdb26659380330009b5d3eaae0e8a3 [file] [log] [blame]
'use strict';
var GetIntrinsic = require('get-intrinsic');
var $TypeError = GetIntrinsic('%TypeError%');
var $fromCharCode = GetIntrinsic('%String.fromCharCode%');
// https://262.ecma-international.org/7.0/#sec-utf16decode
var isLeadingSurrogate = require('../helpers/isLeadingSurrogate');
var isTrailingSurrogate = require('../helpers/isTrailingSurrogate');
// https://262.ecma-international.org/11.0/#sec-utf16decodesurrogatepair
module.exports = function UTF16Decode(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);
};