| Leo Repp | 58b9f11 | 2021-11-22 11:57:47 +0100 | [diff] [blame^] | 1 | 'use strict'; |
| 2 | |
| 3 | var GetIntrinsic = require('get-intrinsic'); |
| 4 | |
| 5 | var $TypeError = GetIntrinsic('%TypeError%'); |
| 6 | var $fromCharCode = GetIntrinsic('%String.fromCharCode%'); |
| 7 | |
| 8 | // https://262.ecma-international.org/7.0/#sec-utf16decode |
| 9 | |
| 10 | var isLeadingSurrogate = require('../helpers/isLeadingSurrogate'); |
| 11 | var isTrailingSurrogate = require('../helpers/isTrailingSurrogate'); |
| 12 | |
| 13 | // https://262.ecma-international.org/11.0/#sec-utf16decodesurrogatepair |
| 14 | |
| 15 | module.exports = function UTF16Decode(lead, trail) { |
| 16 | if (!isLeadingSurrogate(lead) || !isTrailingSurrogate(trail)) { |
| 17 | throw new $TypeError('Assertion failed: `lead` must be a leading surrogate char code, and `trail` must be a trailing surrogate char code'); |
| 18 | } |
| 19 | // var cp = (lead - 0xD800) * 0x400 + (trail - 0xDC00) + 0x10000; |
| 20 | return $fromCharCode(lead) + $fromCharCode(trail); |
| 21 | }; |