securityos/node_modules/es-abstract/2020/IsValidIntegerIndex.js

33 lines
841 B
JavaScript

'use strict';
var $TypeError = require('es-errors/type');
var IsInteger = require('./IsInteger');
var isNegativeZero = require('../helpers/isNegativeZero');
var isTypedArray = require('is-typed-array');
var typedArrayBuffer = require('typed-array-buffer');
// https://262.ecma-international.org/11.0/#sec-isvalidintegerindex
module.exports = function IsValidIntegerIndex(O, index) {
if (!isTypedArray) {
throw new $TypeError('Assertion failed: `O` must be a Typed Array');
}
typedArrayBuffer(O); // step 1
if (typeof index !== 'number') {
throw new $TypeError('Assertion failed: Type(index) is not Number'); // step 2
}
if (!IsInteger(index)) { return false; } // step 3
if (isNegativeZero(index)) { return false; } // step 4
if (index < 0 || index >= O.length) { return false; } // step 5
return true; // step 6
};