Constnium/node_modules/es-abstract/2018/UnicodeEscape.js

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2022-06-23 02:27:43 +02:00
'use strict';
var GetIntrinsic = require('get-intrinsic');
var $TypeError = GetIntrinsic('%TypeError%');
var callBound = require('call-bind/callBound');
var $charCodeAt = callBound('String.prototype.charCodeAt');
var $numberToString = callBound('Number.prototype.toString');
var $toLowerCase = callBound('String.prototype.toLowerCase');
var $strSlice = callBound('String.prototype.slice');
// https://262.ecma-international.org/9.0/#sec-unicodeescape
module.exports = function UnicodeEscape(C) {
if (typeof C !== 'string' || C.length !== 1) {
throw new $TypeError('Assertion failed: `C` must be a single code unit');
}
var n = $charCodeAt(C, 0);
if (n > 0xFFFF) {
throw new $TypeError('`Assertion failed: numeric value of `C` must be <= 0xFFFF');
}
return '\\u' + $strSlice('0000' + $toLowerCase($numberToString(n, 16)), -4);
};