lepu-test-platform-web/node_modules/es-abstract/2016/IterableToArrayLike.js

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'use strict';
var callBound = require('../helpers/callBound');
var $arrayPush = callBound('Array.prototype.push');
var getIteratorMethod = require('../helpers/getIteratorMethod');
var AdvanceStringIndex = require('./AdvanceStringIndex');
var GetIterator = require('./GetIterator');
var GetMethod = require('./GetMethod');
var IsArray = require('./IsArray');
var IteratorStep = require('./IteratorStep');
var IteratorValue = require('./IteratorValue');
var ToObject = require('./ToObject');
var Type = require('./Type');
var ES = {
AdvanceStringIndex: AdvanceStringIndex,
GetMethod: GetMethod,
IsArray: IsArray,
Type: Type
};
// https://www.ecma-international.org/ecma-262/7.0/#sec-iterabletoarraylike
/**
* 1. Let usingIterator be ? GetMethod(items, @@iterator).
* 2. If usingIterator is not undefined, then
* 1. Let iterator be ? GetIterator(items, usingIterator).
* 2. Let values be a new empty List.
* 3. Let next be true.
* 4. Repeat, while next is not false
* 1. Let next be ? IteratorStep(iterator).
* 2. If next is not false, then
* 1. Let nextValue be ? IteratorValue(next).
* 2. Append nextValue to the end of the List values.
* 5. Return CreateArrayFromList(values).
* 3. NOTE: items is not an Iterable so assume it is already an array-like object.
* 4. Return ! ToObject(items).
*/
module.exports = function IterableToArrayLike(items) {
var usingIterator = getIteratorMethod(ES, items);
if (typeof usingIterator !== 'undefined') {
var iterator = GetIterator(items, usingIterator);
var values = [];
var next = true;
while (next) {
next = IteratorStep(iterator);
if (next) {
var nextValue = IteratorValue(next);
$arrayPush(values, nextValue);
}
}
return values;
}
return ToObject(items);
};