| 12345678910111213141516171819202122232425262728293031323334 | 'use strict';var GetIntrinsic = require('get-intrinsic');var CodePointAt = require('./CodePointAt');var IsIntegralNumber = require('./IsIntegralNumber');var Type = require('./Type');var MAX_SAFE_INTEGER = require('../helpers/maxSafeInteger');var $TypeError = GetIntrinsic('%TypeError%');// https://ecma-international.org/ecma-262/12.0/#sec-advancestringindexmodule.exports = function AdvanceStringIndex(S, index, unicode) {	if (Type(S) !== 'String') {		throw new $TypeError('Assertion failed: `S` must be a String');	}	if (!IsIntegralNumber(index) || index < 0 || index > MAX_SAFE_INTEGER) {		throw new $TypeError('Assertion failed: `length` must be an integer >= 0 and <= 2**53');	}	if (Type(unicode) !== 'Boolean') {		throw new $TypeError('Assertion failed: `unicode` must be a Boolean');	}	if (!unicode) {		return index + 1;	}	var length = S.length;	if ((index + 1) >= length) {		return index + 1;	}	var cp = CodePointAt(S, index);	return index + cp['[[CodeUnitCount]]'];};
 |