lepu-test-platform-web/node_modules/es-abstract/2019/ToIndex.js

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'use strict';
var GetIntrinsic = require('../GetIntrinsic');
var $RangeError = GetIntrinsic('%RangeError%');
var ToInteger = require('./ToInteger');
var ToLength = require('./ToLength');
var SameValueZero = require('./SameValueZero');
// https://www.ecma-international.org/ecma-262/8.0/#sec-toindex
module.exports = function ToIndex(value) {
if (typeof value === 'undefined') {
return 0;
}
var integerIndex = ToInteger(value);
if (integerIndex < 0) {
throw new $RangeError('index must be >= 0');
}
var index = ToLength(integerIndex);
if (!SameValueZero(integerIndex, index)) {
throw new $RangeError('index must be >= 0 and < 2 ** 53 - 1');
}
return index;
};