Iterator helpers proposal changes

CHANGELOG.md

@@ -1,5 +1,17 @@
 ## Changelog
 ##### Unreleased
+- Recent updates of the [iterator helpers proposal](https://github.com/tc39/proposal-iterator-helpers), [#1101](https://github.com/zloirock/core-js/issues/1101):
+  - `.asIndexedPairs` renamed to `.indexed`, [proposal-iterator-helpers/183](https://github.com/tc39/proposal-iterator-helpers/pull/183):
+    - `Iterator.prototype.asIndexedPairs` -> `Iterator.prototype.indexed`
+    - `AsyncIterator.prototype.asIndexedPairs` -> `AsyncIterator.prototype.indexed`
+  - Avoid exposing spec fiction `%AsyncFromSyncIteratorPrototype%` in `AsyncIterator.from` and `Iterator.prototype.toAsync`, [proposal-iterator-helpers/182](https://github.com/tc39/proposal-iterator-helpers/pull/182), [proposal-iterator-helpers/202](https://github.com/tc39/proposal-iterator-helpers/pull/202)
+  - Avoid unnecessary promise creation in `%WrapForValidAsyncIteratorPrototype%.next`, [proposal-iterator-helpers/197](https://github.com/tc39/proposal-iterator-helpers/pull/197)
+  - Do not validate value in `%WrapForValid(Async)IteratorPrototype%.next`, [proposal-iterator-helpers/197](https://github.com/tc39/proposal-iterator-helpers/pull/197) and [proposal-iterator-helpers/205](https://github.com/tc39/proposal-iterator-helpers/pull/205)
+  - Do not forward the parameter of `.next` / `.return` to an underlying iterator by the extended iterator protocol, a part of [proposal-iterator-helpers/194](https://github.com/tc39/proposal-iterator-helpers/pull/194)
+  - `.throw` methods removed from all wrappers / helpers prototypes, a part of [proposal-iterator-helpers/194](https://github.com/tc39/proposal-iterator-helpers/pull/194)
+  - Close inner iterators in `{ Iterator, AsyncIterator }.prototype.flatMap` on `.return`, [proposal-iterator-helpers/195](https://github.com/tc39/proposal-iterator-helpers/pull/195)
+  - Throw `RangeError` on `NaN` in `{ Iterator, AsyncIterator }.prototype.{ drop, take }`, [proposal-iterator-helpers/181](https://github.com/tc39/proposal-iterator-helpers/pull/181)
+  - Many other updates and fixes of this proposal
 - Polyfill `Promise` with `unhandledrejection` event support (browser style) in Deno < [1.24](https://github.com/denoland/deno/releases/tag/v1.24.0)
 - Added compat data for Bun, [#1103](https://github.com/zloirock/core-js/issues/1103)
 - Added compat data for Hermes, [#1099](https://github.com/zloirock/core-js/issues/1099)

README.md

@@ -2180,17 +2180,17 @@ correctionNeeded; // => [1, 1, 3]
 core-js(-pure)/stage/2
 ```
 ##### [Iterator helpers](https://github.com/tc39/proposal-iterator-helpers)[⬆](#index)
-Modules [`esnext.async-iterator.constructor`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.constructor.js), [`esnext.async-iterator.as-indexed-pairs`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.as-indexed-pairs.js), [`esnext.async-iterator.drop`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.drop.js), [`esnext.async-iterator.every`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.every.js), [`esnext.async-iterator.filter`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.filter.js), [`esnext.async-iterator.find`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.find.js), [`esnext.async-iterator.flat-map`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.flat-map.js), [`esnext.async-iterator.for-each`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.for-each.js), [`esnext.async-iterator.from`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.from.js), [`esnext.async-iterator.map`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.map.js), [`esnext.async-iterator.reduce`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.reduce.js), [`esnext.async-iterator.some`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.some.js), [`esnext.async-iterator.take`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.take.js), [`esnext.async-iterator.to-array`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.to-array.js), [`esnext.iterator.constructor`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.constructor.js), [`esnext.iterator.as-indexed-pairs`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.as-indexed-pairs.js), [`esnext.iterator.drop`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.drop.js), [`esnext.iterator.every`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.every.js), [`esnext.iterator.filter`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.filter.js), [`esnext.iterator.find`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.find.js), [`esnext.iterator.flat-map`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.flat-map.js), [`esnext.iterator.for-each`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.for-each.js), [`esnext.iterator.from`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.from.js), [`esnext.iterator.map`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.map.js), [`esnext.iterator.reduce`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.reduce.js), [`esnext.iterator.some`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.some.js), [`esnext.iterator.take`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.take.js), [`esnext.iterator.to-array`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.to-array.js) and [`esnext.iterator.to-async`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.to-async.js)
+Modules [`esnext.async-iterator.constructor`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.constructor.js), [`esnext.async-iterator.drop`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.drop.js), [`esnext.async-iterator.every`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.every.js), [`esnext.async-iterator.filter`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.filter.js), [`esnext.async-iterator.find`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.find.js), [`esnext.async-iterator.flat-map`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.flat-map.js), [`esnext.async-iterator.for-each`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.for-each.js), [`esnext.async-iterator.from`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.from.js), [`esnext.async-iterator.indexed`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.indexed.js), [`esnext.async-iterator.map`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.map.js), [`esnext.async-iterator.reduce`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.reduce.js), [`esnext.async-iterator.some`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.some.js), [`esnext.async-iterator.take`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.take.js), [`esnext.async-iterator.to-array`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.async-iterator.to-array.js), [`esnext.iterator.constructor`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.constructor.js), [`esnext.iterator.drop`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.drop.js), [`esnext.iterator.every`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.every.js), [`esnext.iterator.filter`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.filter.js), [`esnext.iterator.find`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.find.js), [`esnext.iterator.flat-map`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.flat-map.js), [`esnext.iterator.for-each`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.for-each.js), [`esnext.iterator.from`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.from.js), [`esnext.iterator.indexed`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.indexed.js), [`esnext.iterator.map`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.map.js), [`esnext.iterator.reduce`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.reduce.js), [`esnext.iterator.some`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.some.js), [`esnext.iterator.take`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.take.js), [`esnext.iterator.to-array`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.to-array.js) and [`esnext.iterator.to-async`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/esnext.iterator.to-async.js)
 ```js
 class Iterator {
   static from(iterable: Iterable<mixed>): Iterator<any>;
-  asIndexedPairs(): Iterator<[index, any]>;
   drop(limit: uint): Iterator<any>;
   every(callbackfn: value: any => boolean): boolean;
   filter(callbackfn: value: any => boolean): Iterator<any>;
   find(callbackfn: value: any => boolean)): any;
   flatMap(callbackfn: value => any: Iterable): Iterator<any>;
   forEach(callbackfn: value => void): void;
+  indexed(): Iterator<[index, any]>;
   map(callbackfn: value => any): Iterator<any>;
   reduce(callbackfn: (memo: any, value: any) => any, initialValue: any): any;
   some(callbackfn: value: any => boolean): boolean;
@@ -2202,13 +2202,13 @@ class Iterator {
 
 class AsyncIterator {
   static from(iterable: Iterable<mixed>): AsyncIterator<any>;
-  asIndexedPairs(): AsyncIterator<[index, any]>;
   drop(limit: uint): AsyncIterator<any>;
   every(async callbackfn: value: any => boolean): Promise<boolean>;
   filter(async callbackfn: value: any => boolean): AsyncIterator<any>;
   find(async callbackfn: value: any => boolean)): Promise<any>;
   flatMap(async callbackfn: value => any: Iterable): AsyncIterator<any>;
   forEach(async callbackfn: value => void): Promise<void>;
+  indexed(): AsyncIterator<[index, any]>;
   map(async callbackfn: value => any): AsyncIterator<any>;
   reduce(async callbackfn: (memo: any, value: any) => any, initialValue: any): Promise<any>;
   some(async callbackfn: value: any => boolean): Promise<boolean>;
@@ -2221,28 +2221,28 @@ class AsyncIterator {
 ```js
 core-js/proposals/iterator-helpers
 core-js(-pure)/full/async-iterator
-core-js(-pure)/full/async-iterator/as-indexed-pairs
 core-js(-pure)/full/async-iterator/drop
 core-js(-pure)/full/async-iterator/every
 core-js(-pure)/full/async-iterator/filter
 core-js(-pure)/full/async-iterator/find
 core-js(-pure)/full/async-iterator/flat-map
 core-js(-pure)/full/async-iterator/for-each
 core-js(-pure)/full/async-iterator/from
+core-js(-pure)/full/async-iterator/indexed
 core-js(-pure)/full/async-iterator/map
 core-js(-pure)/full/async-iterator/reduce
 core-js(-pure)/full/async-iterator/some
 core-js(-pure)/full/async-iterator/take
 core-js(-pure)/full/async-iterator/to-array
 core-js(-pure)/full/iterator
-core-js(-pure)/full/iterator/as-indexed-pairs
 core-js(-pure)/full/iterator/drop
 core-js(-pure)/full/iterator/every
 core-js(-pure)/full/iterator/filter
 core-js(-pure)/full/iterator/find
 core-js(-pure)/full/iterator/flat-map
 core-js(-pure)/full/iterator/for-each
 core-js(-pure)/full/iterator/from
+core-js(-pure)/full/iterator/indexed
 core-js(-pure)/full/iterator/map
 core-js(-pure)/full/iterator/reduce
 core-js(-pure)/full/iterator/some

packages/core-js-compat/src/data.mjs

@@ -2080,6 +2080,7 @@ export const data = {
   },
   'esnext.async-iterator.constructor': {
   },
+  // TODO: Remove from `core-js@4`
   'esnext.async-iterator.as-indexed-pairs': {
   },
   'esnext.async-iterator.drop': {
@@ -2096,6 +2097,8 @@ export const data = {
   },
   'esnext.async-iterator.from': {
   },
+  'esnext.async-iterator.indexed': {
+  },
   'esnext.async-iterator.map': {
   },
   'esnext.async-iterator.reduce': {
@@ -2122,6 +2125,7 @@ export const data = {
   'esnext.global-this': null,
   'esnext.iterator.constructor': {
   },
+  // TODO: Remove from `core-js@4`
   'esnext.iterator.as-indexed-pairs': {
   },
   'esnext.iterator.drop': {
@@ -2138,6 +2142,8 @@ export const data = {
   },
   'esnext.iterator.from': {
   },
+  'esnext.iterator.indexed': {
+  },
   'esnext.iterator.map': {
   },
   'esnext.iterator.reduce': {

packages/core-js-compat/src/modules-by-versions.mjs

@@ -150,4 +150,8 @@ export default {
     'esnext.array.group-to-map',
     'esnext.symbol.metadata-key',
   ],
+  3.24: [
+    'esnext.async-iterator.indexed',
+    'esnext.iterator.indexed',
+  ],
 };

packages/core-js/full/async-iterator/index.js

@@ -3,6 +3,7 @@ require('../../modules/es.object.to-string');
 require('../../modules/es.promise');
 require('../../modules/es.string.iterator');
 require('../../modules/esnext.async-iterator.constructor');
+// TODO: Remove from `core-js@4`
 require('../../modules/esnext.async-iterator.as-indexed-pairs');
 require('../../modules/esnext.async-iterator.drop');
 require('../../modules/esnext.async-iterator.every');
@@ -11,6 +12,7 @@ require('../../modules/esnext.async-iterator.find');
 require('../../modules/esnext.async-iterator.flat-map');
 require('../../modules/esnext.async-iterator.for-each');
 require('../../modules/esnext.async-iterator.from');
+require('../../modules/esnext.async-iterator.indexed');
 require('../../modules/esnext.async-iterator.map');
 require('../../modules/esnext.async-iterator.reduce');
 require('../../modules/esnext.async-iterator.some');

packages/core-js/full/async-iterator/indexed.js

@@ -0,0 +1,8 @@
+require('../../modules/es.object.to-string');
+require('../../modules/es.promise');
+require('../../modules/esnext.async-iterator.constructor');
+require('../../modules/esnext.async-iterator.indexed');
+
+var entryUnbind = require('../../internals/entry-unbind');
+
+module.exports = entryUnbind('AsyncIterator', 'indexed');

packages/core-js/full/iterator/index.js

@@ -3,6 +3,7 @@ require('../../modules/es.object.to-string');
 require('../../modules/es.promise');
 require('../../modules/es.string.iterator');
 require('../../modules/esnext.iterator.constructor');
+// TODO: Remove from `core-js@4`
 require('../../modules/esnext.iterator.as-indexed-pairs');
 require('../../modules/esnext.iterator.drop');
 require('../../modules/esnext.iterator.every');
@@ -11,6 +12,7 @@ require('../../modules/esnext.iterator.find');
 require('../../modules/esnext.iterator.flat-map');
 require('../../modules/esnext.iterator.for-each');
 require('../../modules/esnext.iterator.from');
+require('../../modules/esnext.iterator.indexed');
 require('../../modules/esnext.iterator.map');
 require('../../modules/esnext.iterator.reduce');
 require('../../modules/esnext.iterator.some');

packages/core-js/full/iterator/indexed.js

@@ -0,0 +1,8 @@
+require('../../modules/es.object.to-string');
+require('../../modules/esnext.iterator.constructor');
+require('../../modules/esnext.iterator.indexed');
+
+var entryUnbind = require('../../internals/entry-unbind');
+
+module.exports = entryUnbind('Iterator', 'indexed');
+

packages/core-js/internals/async-from-sync-iterator.js

@@ -1,5 +1,5 @@
 'use strict';
-var apply = require('../internals/function-apply');
+var call = require('../internals/function-call');
 var anObject = require('../internals/an-object');
 var create = require('../internals/object-create');
 var getMethod = require('../internals/get-method');
@@ -30,31 +30,19 @@ var AsyncFromSyncIterator = function AsyncIterator(iterator) {
 };
 
 AsyncFromSyncIterator.prototype = defineBuiltIns(create(AsyncIteratorPrototype), {
-  next: function next(arg) {
+  next: function next() {
     var state = getInternalState(this);
-    var hasArg = !!arguments.length;
     return new Promise(function (resolve, reject) {
-      var result = anObject(apply(state.next, state.iterator, hasArg ? [arg] : []));
+      var result = anObject(call(state.next, state.iterator));
       asyncFromSyncIteratorContinuation(result, resolve, reject);
     });
   },
-  'return': function (arg) {
+  'return': function () {
     var iterator = getInternalState(this).iterator;
-    var hasArg = !!arguments.length;
     return new Promise(function (resolve, reject) {
       var $return = getMethod(iterator, 'return');
-      if ($return === undefined) return resolve({ done: true, value: arg });
-      var result = anObject(apply($return, iterator, hasArg ? [arg] : []));
-      asyncFromSyncIteratorContinuation(result, resolve, reject);
-    });
-  },
-  'throw': function (arg) {
-    var iterator = getInternalState(this).iterator;
-    var hasArg = !!arguments.length;
-    return new Promise(function (resolve, reject) {
-      var $throw = getMethod(iterator, 'throw');
-      if ($throw === undefined) return reject(arg);
-      var result = anObject(apply($throw, iterator, hasArg ? [arg] : []));
+      if ($return === undefined) return resolve({ done: true, value: undefined });
+      var result = anObject(call($return, iterator));
       asyncFromSyncIteratorContinuation(result, resolve, reject);
     });
   }

packages/core-js/internals/async-iterator-close.js

@@ -0,0 +1,18 @@
+var call = require('../internals/function-call');
+var getBuiltIn = require('../internals/get-built-in');
+var getMethod = require('../internals/get-method');
+
+module.exports = function (iterator, method, argument, reject) {
+  try {
+    var returnMethod = getMethod(iterator, 'return');
+    if (returnMethod) {
+      return getBuiltIn('Promise').resolve(call(returnMethod, iterator)).then(function () {
+        method(argument);
+      }, function (error) {
+        reject(error);
+      });
+    }
+  } catch (error2) {
+    return reject(error2);
+  } method(argument);
+};