es2017.js
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'use strict';
var GetIntrinsic = require('./GetIntrinsic');
var ES2016 = require('./es2016');
var assign = require('./helpers/assign');
var forEach = require('./helpers/forEach');
var callBind = require('./helpers/callBind');
var $TypeError = GetIntrinsic('%TypeError%');
var callBound = require('./helpers/callBound');
var $isEnumerable = callBound('Object.prototype.propertyIsEnumerable');
var $pushApply = callBind.apply(GetIntrinsic('%Array.prototype.push%'));
var $arrayPush = callBound('Array.prototype.push');
var ES2017 = assign(assign({}, ES2016), {
ToIndex: function ToIndex(value) {
if (typeof value === 'undefined') {
return 0;
}
var integerIndex = this.ToInteger(value);
if (integerIndex < 0) {
throw new RangeError('index must be >= 0');
}
var index = this.ToLength(integerIndex);
if (!this.SameValueZero(integerIndex, index)) {
throw new RangeError('index must be >= 0 and < 2 ** 53 - 1');
}
return index;
},
// https://www.ecma-international.org/ecma-262/8.0/#sec-enumerableownproperties
EnumerableOwnProperties: function EnumerableOwnProperties(O, kind) {
var keys = ES2016.EnumerableOwnNames(O);
if (kind === 'key') {
return keys;
}
if (kind === 'value' || kind === 'key+value') {
var results = [];
forEach(keys, function (key) {
if ($isEnumerable(O, key)) {
$pushApply(results, [
kind === 'value' ? O[key] : [key, O[key]]
]);
}
});
return results;
}
throw new $TypeError('Assertion failed: "kind" is not "key", "value", or "key+value": ' + kind);
},
// https://www.ecma-international.org/ecma-262/8.0/#sec-iterabletolist
IterableToList: function IterableToList(items, method) {
var iterator = this.GetIterator(items, method);
var values = [];
var next = true;
while (next) {
next = this.IteratorStep(iterator);
if (next) {
var nextValue = this.IteratorValue(next);
$arrayPush(values, nextValue);
}
}
return values;
}
});
delete ES2017.EnumerableOwnNames; // replaced with EnumerableOwnProperties
delete ES2017.IterableToArrayLike; // replaced with IterableToList
module.exports = ES2017;