| 'use strict'; |
| |
| var GetIntrinsic = require('get-intrinsic'); |
| |
| var $TypeError = GetIntrinsic('%TypeError%'); |
| 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 UTF16DecodeSurrogatePair(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); |
| }; |