Lobashov_Ivan_PIBD-21_IP/Lab2/node_modules/es-abstract/2020/AdvanceStringIndex.js

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2024-01-10 22:39:31 +04:00
'use strict';
var GetIntrinsic = require('get-intrinsic');
var CodePointAt = require('./CodePointAt');
var Type = require('./Type');
var isInteger = require('../helpers/isInteger');
var MAX_SAFE_INTEGER = require('../helpers/maxSafeInteger');
var $TypeError = GetIntrinsic('%TypeError%');
// https://262.ecma-international.org/11.0/#sec-advancestringindex
module.exports = function AdvanceStringIndex(S, index, unicode) {
if (Type(S) !== 'String') {
throw new $TypeError('Assertion failed: `S` must be a String');
}
if (!isInteger(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]]'];
};