22 lines
821 B
JavaScript
22 lines
821 B
JavaScript
'use strict';
|
|
|
|
var GetIntrinsic = require('get-intrinsic');
|
|
|
|
var $TypeError = require('es-errors/type');
|
|
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);
|
|
};
|