Fix es-iterator-helpers test fails

packages/npm/es-iterator-helpers/Iterator.concat/implementation.js

@@ -21,11 +21,9 @@ module.exports =
   typeof IteratorConcat === 'function'
     ? IteratorConcat
     : function concat(...iterables) {
-        // ECMAScript Standard Built-in Objects
+        // Built-in functions that are not identified as constructors do
+        // not implement [[Construct]] unless otherwise specified.
         // https://tc39.es/ecma262/#sec-ecmascript-standard-built-in-objects
-        // Built-in function objects that are not identified as constructors do
-        // not implement the [[Construct]] internal method unless otherwise
-        // specified in the description of a particular function.
         if (new.target) {
           throw new TypeErrorCtor('`Iterator.concat` is not a constructor')
         }
@@ -36,37 +34,48 @@ module.exports =
         for (let i = 0; i < length; i += 1) {
           const iterable = iterables[i]
           // Step 2.a: If item is not an Object, throw a TypeError exception.
+          ensureObject(iterable, 'iterable')
           // Step 2.b: Let method be GetMethod(item, %Symbol.iterator%).
+          const method = getMethod(iterable, SymbolIterator)
           // Step 2.c: If method is undefined, throw a TypeError exception.
+          if (method === undefined) {
+            throw new TypeErrorCtor(
+              '`Iterator.concat` requires all arguments to be iterable'
+            )
+          }
           // (Handled by getMethod, which throws if method is missing or not callable.)
           records[i] = {
             iterable,
             openMethod: getMethod(iterable, SymbolIterator)
           }
         }
         let index = 0
+        let innerIterator = null
         // Step 3: Let closure be a new Abstract Closure that captures iterables.
         const closure = {
           // This closure will perform the steps defined in Step 3.a.
           next() {
-            const { length } = records
             while (index < length) {
-              const { iterable, openMethod } = records[index]
-              // Step 3.a.i: Let iter be Call(iterable.[[OpenMethod]], iterable.[[Iterable]]).
-              const iterator = ReflectApply(openMethod, iterable, [])
-              // Step 3.a.ii: If iter is not an Object, throw a TypeError exception.
-              ensureObject(iterator)
+              if (!innerIterator) {
+                // If we haven't initialized an inner iterator yet, do so
+                const { iterable, openMethod } = records[index]
+                // Step 3.a.i: Let iter be Call(iterable.[[OpenMethod]], iterable.[[Iterable]]).
+                innerIterator = ReflectApply(openMethod, iterable, [])
+                // Step 3.a.ii: If iter is not an Object, throw a TypeError exception.
+                ensureObject(innerIterator, 'iterator')
+              }
               // Step 3.a.iii: Let iteratorRecord be GetIteratorDirect(iter).
-              const { next } = getIteratorDirect(iterator)
+              const { next } = getIteratorDirect(innerIterator)
               // Step 3.a.iv: Let innerAlive be true.
               // (Handled by the loop structure)
               // Step 3.a.v: Repeat, while innerAlive is true.
-              const result = ReflectApply(next, iterator, [])
+              const result = ReflectApply(next, innerIterator, [])
               if (!result.done) {
                 // Step 3.a.v.3.a: Yield the value of the iterator.
                 return result
               }
               // Step 3.a.v.2: If innerValue is done, move to the next iterable.
+              innerIterator = null
               index += 1
             }
             // Step 3.b: Return Completion(undefined).

packages/npm/es-iterator-helpers/Iterator.concat/polyfill.js

@@ -1,8 +1,7 @@
 'use strict'
 
 const impl = require('./implementation')
-const Iterator = require('../Iterator/implementation')
 
 module.exports = function getPolyfill() {
-  return typeof Iterator.concat === 'function' ? Iterator.concat : impl
+  return impl
 }

packages/npm/es-iterator-helpers/Iterator.concat/shim.js

@@ -1,14 +1,14 @@
 'use strict'
 
 const getPolyfill = require('./polyfill')
-const Iterator = require('../Iterator/implementation')
+const IteratorCtor = require('../Iterator/implementation')
 
 const { defineProperty: ObjectDefineProperty } = Object
 
 module.exports = function shimIteratorConcat() {
   const polyfill = getPolyfill()
-  if (Iterator.concat !== polyfill) {
-    ObjectDefineProperty(Iterator, 'concat', {
+  if (IteratorCtor.concat !== polyfill) {
+    ObjectDefineProperty(IteratorCtor, 'concat', {
       __proto__: null,
       configurable: true,
       enumerable: false,

packages/npm/es-iterator-helpers/Iterator.from/implementation.js

@@ -1,23 +1,41 @@
 'use strict'
 
+const IteratorCtor = require('../Iterator/implementation')
 const {
-  ReflectApply,
+  IteratorCtor: IteratorCtorRaw,
+  ObjectCreate,
   TypeErrorCtor,
-  createIteratorFromClosure,
+  WrapForValidIteratorPrototype,
   getIteratorFlattenable,
-  setUnderlyingIterator
+  setIterated
 } = require('../shared')
 
-module.exports = function from(O) {
-  if (new.target) {
-    throw new TypeErrorCtor('`Iterator.from` is not a constructor')
-  }
-  const { iterator, next } = getIteratorFlattenable(O)
-  const wrapper = createIteratorFromClosure({
-    next() {
-      return ReflectApply(next, iterator, [])
-    }
-  })
-  setUnderlyingIterator(wrapper, iterator)
-  return wrapper
-}
+const IteratorFrom = IteratorCtorRaw?.from
+
+// Based specification text:
+// https://tc39.es/ecma262/#sec-iterator.from
+module.exports =
+  typeof IteratorFrom === 'function'
+    ? IteratorFrom
+    : function from(O) {
+        // Built-in functions that are not identified as constructors do
+        // not implement [[Construct]] unless otherwise specified.
+        // https://tc39.es/ecma262/#sec-ecmascript-standard-built-in-objects
+        if (new.target) {
+          throw new TypeErrorCtor('`Iterator.from` is not a constructor')
+        }
+        // Step 1: Let iteratorRecord be GetIteratorFlattenable(O, iterate-string-primitives).
+        const { iterator, next } = getIteratorFlattenable(O, true)
+        // Step 2: Let hasInstance be OrdinaryHasInstance(%Iterator%, iteratorRecord.[[Iterator]]).
+        // Step 3: If hasInstance is true, then
+        if (iterator instanceof IteratorCtor) {
+          // Step 3.a: Return iteratorRecord.[[Iterator]].
+          return iterator
+        }
+        // Step 4: Let wrapper be OrdinaryObjectCreate(%WrapForValidIteratorPrototype%, << [[Iterated]] >>).
+        const wrapper = ObjectCreate(WrapForValidIteratorPrototype)
+        // Step 5: Set wrapper.[[Iterated]] to iteratorRecord.
+        setIterated(wrapper, { iterator, next })
+        // Step 6: Return wrapper.
+        return wrapper
+      }

packages/npm/es-iterator-helpers/Iterator.from/shim.js

@@ -1,14 +1,14 @@
 'use strict'
 
 const getPolyfill = require('./polyfill')
-const Iterator = require('../Iterator/implementation')
+const IteratorCtor = require('../Iterator/implementation')
 
 const { defineProperty: ObjectDefineProperty } = Object
 
 module.exports = function shimIteratorFrom() {
   const polyfill = getPolyfill()
   if (Iterator.from !== polyfill) {
-    ObjectDefineProperty(Iterator, 'from', {
+    ObjectDefineProperty(IteratorCtor, 'from', {
       __proto__: null,
       configurable: true,
       enumerable: false,

packages/npm/es-iterator-helpers/Iterator.prototype.drop/implementation.js

@@ -16,11 +16,9 @@ const {
 // Based specification text:
 // https://tc39.es/ecma262/#sec-iterator.prototype.drop
 module.exports = function drop(limit) {
-  // ECMAScript Standard Built-in Objects
+  // Built-in functions that are not identified as constructors do
+  // not implement [[Construct]] unless otherwise specified.
   // https://tc39.es/ecma262/#sec-ecmascript-standard-built-in-objects
-  // Built-in function objects that are not identified as constructors do
-  // not implement the [[Construct]] internal method unless otherwise
-  // specified in the description of a particular function.
   if (new.target) {
     throw new TypeErrorCtor('`drop` is not a constructor')
   }

packages/npm/es-iterator-helpers/Iterator.prototype.filter/implementation.js

@@ -13,11 +13,9 @@ const {
 // Based specification text:
 // https://tc39.es/ecma262/#sec-iterator.prototype.filter
 module.exports = function filter(predicate) {
-  // ECMAScript Standard Built-in Objects
+  // Built-in functions that are not identified as constructors do
+  // not implement [[Construct]] unless otherwise specified.
   // https://tc39.es/ecma262/#sec-ecmascript-standard-built-in-objects
-  // Built-in function objects that are not identified as constructors do
-  // not implement the [[Construct]] internal method unless otherwise
-  // specified in the description of a particular function.
   if (new.target) {
     throw new TypeErrorCtor('`filter` is not a constructor')
   }

packages/npm/es-iterator-helpers/Iterator.prototype.flatMap/implementation.js

@@ -14,11 +14,9 @@ const {
 } = require('../shared')
 
 module.exports = function flatMap(mapper) {
-  // ECMAScript Standard Built-in Objects
+  // Built-in functions that are not identified as constructors do
+  // not implement [[Construct]] unless otherwise specified.
   // https://tc39.es/ecma262/#sec-ecmascript-standard-built-in-objects
-  // Built-in function objects that are not identified as constructors do
-  // not implement the [[Construct]] internal method unless otherwise
-  // specified in the description of a particular function.
   if (new.target) {
     throw new TypeErrorCtor('`flatMap` is not a constructor')
   }

packages/npm/es-iterator-helpers/Iterator.prototype.map/implementation.js

@@ -13,11 +13,9 @@ const {
 // Based on the specification text:
 // https://tc39.es/ecma262/#sec-iterator.prototype.map
 module.exports = function map(mapper) {
-  // ECMAScript Standard Built-in Objects
+  // Built-in functions that are not identified as constructors do
+  // not implement [[Construct]] unless otherwise specified.
   // https://tc39.es/ecma262/#sec-ecmascript-standard-built-in-objects
-  // Built-in function objects that are not identified as constructors do
-  // not implement the [[Construct]] internal method unless otherwise
-  // specified in the description of a particular function.
   if (new.target) {
     throw new TypeErrorCtor('`Iterator.map` is not a constructor')
   }

packages/npm/es-iterator-helpers/Iterator.prototype.toArray/implementation.js

@@ -8,17 +8,29 @@ const {
 } = require('../shared')
 
 module.exports = function toArray() {
+  // Built-in functions that are not identified as constructors do
+  // not implement [[Construct]] unless otherwise specified.
+  // https://tc39.es/ecma262/#sec-ecmascript-standard-built-in-objects
   if (new.target) {
     throw new TypeErrorCtor('`toArray` is not a constructor')
   }
-  ensureObject(this)
+  // Step 1: Let O be the this value.
+  const O = this
+  // Step 2: If O is not an Object, throw a TypeError exception.
+  ensureObject(O)
+  // Step 3: Let iterated be GetIteratorDirect(O).
   const { iterator, next } = getIteratorDirect(this)
+  // Step 4: Let items be a new empty List.
   const items = []
+  // Step 5: Repeat.
   while (true) {
+    // Step 5.a: Let value be IteratorStepValue(iterated).
     const result = ReflectApply(next, iterator, [])
+    // Step 5.b: If value is done, return CreateArrayFromList(items).
     if (result.done) {
       return items
     }
+    // Step 5.c: Append value to items.
     items[items.length] = result.value
   }
 }

packages/npm/es-iterator-helpers/Iterator.prototype/shim.js

@@ -1,14 +1,14 @@
 'use strict'
 
 const getPolyfill = require('./polyfill')
-const Iterator = require('../Iterator/implementation')
+const IteratorCtor = require('../Iterator/implementation')
 
 const { defineProperty: ObjectDefineProperty } = Object
 
 module.exports = function shimIteratorProto() {
   const polyfill = getPolyfill()
-  if (Iterator.prototype !== polyfill) {
-    ObjectDefineProperty(Iterator, 'prototype', {
+  if (IteratorCtor.prototype !== polyfill) {
+    ObjectDefineProperty(IteratorCtor, 'prototype', {
       __proto__: null,
       configurable: true,
       enumerable: false,

packages/npm/es-iterator-helpers/shared.d.ts

@@ -1,22 +1,32 @@
-declare interface IteratorResult<T> {
-  value: T
-  done: boolean
-}
 declare interface Iterator<T> {
   next(value?: any): IteratorResult<T>
   return?(value?: any): IteratorResult<T>
   [Symbol.iterator](): Iterator<T>
 }
+declare interface IteratorHelper<T> extends Iterator<T> {
+  [Symbol.toStringTag](): 'Iterator Helper'
+}
+declare interface IteratorRecord<T> {
+  iterator: Iterator<T>
+  next: () => IteratorResult<T>
+}
+declare interface IteratorResult<T> {
+  value: T
+  done: boolean
+}
 declare interface InternalShared {
   SLOT: WeakMap<any, any>
   SLOT_GENERATOR_CONTEXT: string
   SLOT_GENERATOR_STATE: string
+  SLOT_ITERATED: string
   SLOT_UNDERLYING_ITERATOR: string
   GENERATOR_STATE_COMPLETED: string
   GENERATOR_STATE_SUSPENDED_STARTED: string
   IteratorCtor: typeof globalThis.Iterator
-  IteratorPrototype: any
-  IteratorHelperPrototype: any
+  ArrayCtor: ArrayConstructor
+  IteratorPrototype: Iterator<any>
+  IteratorHelperPrototype: IteratorHelper<any>
+  WrapForValidIteratorPrototype: Iterator<any>
   NumberCtor: NumberConstructor
   MathTrunc: (x: number) => number
   NegativeInfinity: number
@@ -30,17 +40,11 @@ declare interface InternalShared {
   SymbolToStringTag: symbol
   TypeErrorCtor: typeof TypeError
   abruptCloseIterator(iterator: Iterator<any>, error: any): void
-  closeIterator<T>(iterator: Iterator<any>, completion: T): T
+  closeIterator<T>(iterator: Iterator<T>, completion: T): T
   createIteratorFromClosure<T>(closure: Iterator<T>): Iterator<T>
   ensureObject(thisArg: any, what?: string): void
-  getIteratorDirect<T>(obj: any): {
-    next: () => IteratorResult<T>
-    iterator: Iterator<T>
-  }
-  getIteratorFlattenable(obj: any): {
-    next: () => IteratorResult<any>
-    iterator: Iterator<any>
-  }
+  getIteratorDirect<T>(obj: any): IteratorRecord<T>
+  getIteratorFlattenable(obj: any): IteratorRecord<any>
   getMethod(
     obj: any,
     key: string | symbol
@@ -53,7 +57,8 @@ declare interface InternalShared {
   isObjectType(value: any): boolean
   resolveSlots(O: any, slot: string): any
   setSlot(O: any, slot: string, value: any): void
-  setUnderlyingIterator(generator: any, iterator: any): void
+  setUnderlyingIterator(generator: Iterator<any>, iterator: Iterator<any>): void
+  setIterated(wrapper: Iterator<any>, record: IteratorRecord<any>): void
   toIntegerOrInfinity(value: any): number
 }
 declare const shared: InternalShared