2 var $ = require('../internals/export');
3 var createIteratorConstructor = require('../internals/create-iterator-constructor');
4 var getPrototypeOf = require('../internals/object-get-prototype-of');
5 var setPrototypeOf = require('../internals/object-set-prototype-of');
6 var setToStringTag = require('../internals/set-to-string-tag');
7 var createNonEnumerableProperty = require('../internals/create-non-enumerable-property');
8 var redefine = require('../internals/redefine');
9 var wellKnownSymbol = require('../internals/well-known-symbol');
10 var IS_PURE = require('../internals/is-pure');
11 var Iterators = require('../internals/iterators');
12 var IteratorsCore = require('../internals/iterators-core');
14 var IteratorPrototype = IteratorsCore.IteratorPrototype;
15 var BUGGY_SAFARI_ITERATORS = IteratorsCore.BUGGY_SAFARI_ITERATORS;
16 var ITERATOR = wellKnownSymbol('iterator');
18 var VALUES = 'values';
19 var ENTRIES = 'entries';
21 var returnThis = function () { return this; };
23 module.exports = function (Iterable, NAME, IteratorConstructor, next, DEFAULT, IS_SET, FORCED) {
24 createIteratorConstructor(IteratorConstructor, NAME, next);
26 var getIterationMethod = function (KIND) {
27 if (KIND === DEFAULT && defaultIterator) return defaultIterator;
28 if (!BUGGY_SAFARI_ITERATORS && KIND in IterablePrototype) return IterablePrototype[KIND];
30 case KEYS: return function keys() { return new IteratorConstructor(this, KIND); };
31 case VALUES: return function values() { return new IteratorConstructor(this, KIND); };
32 case ENTRIES: return function entries() { return new IteratorConstructor(this, KIND); };
33 } return function () { return new IteratorConstructor(this); };
36 var TO_STRING_TAG = NAME + ' Iterator';
37 var INCORRECT_VALUES_NAME = false;
38 var IterablePrototype = Iterable.prototype;
39 var nativeIterator = IterablePrototype[ITERATOR]
40 || IterablePrototype['@@iterator']
41 || DEFAULT && IterablePrototype[DEFAULT];
42 var defaultIterator = !BUGGY_SAFARI_ITERATORS && nativeIterator || getIterationMethod(DEFAULT);
43 var anyNativeIterator = NAME == 'Array' ? IterablePrototype.entries || nativeIterator : nativeIterator;
44 var CurrentIteratorPrototype, methods, KEY;
47 if (anyNativeIterator) {
48 CurrentIteratorPrototype = getPrototypeOf(anyNativeIterator.call(new Iterable()));
49 if (IteratorPrototype !== Object.prototype && CurrentIteratorPrototype.next) {
50 if (!IS_PURE && getPrototypeOf(CurrentIteratorPrototype) !== IteratorPrototype) {
52 setPrototypeOf(CurrentIteratorPrototype, IteratorPrototype);
53 } else if (typeof CurrentIteratorPrototype[ITERATOR] != 'function') {
54 createNonEnumerableProperty(CurrentIteratorPrototype, ITERATOR, returnThis);
57 // Set @@toStringTag to native iterators
58 setToStringTag(CurrentIteratorPrototype, TO_STRING_TAG, true, true);
59 if (IS_PURE) Iterators[TO_STRING_TAG] = returnThis;
63 // fix Array#{values, @@iterator}.name in V8 / FF
64 if (DEFAULT == VALUES && nativeIterator && nativeIterator.name !== VALUES) {
65 INCORRECT_VALUES_NAME = true;
66 defaultIterator = function values() { return nativeIterator.call(this); };
70 if ((!IS_PURE || FORCED) && IterablePrototype[ITERATOR] !== defaultIterator) {
71 createNonEnumerableProperty(IterablePrototype, ITERATOR, defaultIterator);
73 Iterators[NAME] = defaultIterator;
75 // export additional methods
78 values: getIterationMethod(VALUES),
79 keys: IS_SET ? defaultIterator : getIterationMethod(KEYS),
80 entries: getIterationMethod(ENTRIES)
82 if (FORCED) for (KEY in methods) {
83 if (BUGGY_SAFARI_ITERATORS || INCORRECT_VALUES_NAME || !(KEY in IterablePrototype)) {
84 redefine(IterablePrototype, KEY, methods[KEY]);
86 } else $({ target: NAME, proto: true, forced: BUGGY_SAFARI_ITERATORS || INCORRECT_VALUES_NAME }, methods);