early exit on broken .next in missed cases of `{ Iterator, AsyncIte…

…rator }.from` tc39/proposal-iterator-helpers#232
zloirock · Sep 14, 2022 · d3cff77 · d3cff77
1 parent 8f64706
commit d3cff77
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Showing 7 changed files with 22 additions and 20 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,5 +1,6 @@
 ## Changelog
 ##### Unreleased
+- Early exit on broken `.next` in missed cases of `{ Iterator, AsyncIterator }.from`, [proposal-iterator-helpers/232](https://github.com/tc39/proposal-iterator-helpers/pull/232)
 - Considering `document.all` as a callable in some missed cases
 - Added Safari 16.0 compat data
 - Added iOS Safari 16.0 compat data mapping

diff --git a/packages/core-js/internals/array-from-async.js b/packages/core-js/internals/array-from-async.js
@@ -4,6 +4,7 @@ var toObject = require('../internals/to-object');
 var isConstructor = require('../internals/is-constructor');
 var getAsyncIterator = require('../internals/get-async-iterator');
 var getIterator = require('../internals/get-iterator');
+var getIteratorDirect = require('../internals/get-iterator-direct');
 var getIteratorMethod = require('../internals/get-iterator-method');
 var getMethod = require('../internals/get-method');
 var getVirtual = require('../internals/entry-virtual');
@@ -30,7 +31,7 @@ module.exports = function fromAsync(asyncItems /* , mapfn = undefined, thisArg =
     var A = isConstructor(C) ? new C() : [];
     var iterator = usingAsyncIterator
       ? getAsyncIterator(O, usingAsyncIterator)
-      : new AsyncFromSyncIterator(getIterator(O, usingSyncIterator));
+      : new AsyncFromSyncIterator(getIteratorDirect(getIterator(O, usingSyncIterator)));
     resolve(toArray(iterator, mapfn, A));
   });
 };
diff --git a/packages/core-js/internals/async-from-sync-iterator.js b/packages/core-js/internals/async-from-sync-iterator.js
@@ -22,12 +22,9 @@ var asyncFromSyncIteratorContinuation = function (result, resolve, reject) {
   }, reject);
 };
 
-var AsyncFromSyncIterator = function AsyncIterator(iterator) {
-  setInternalState(this, {
-    type: ASYNC_FROM_SYNC_ITERATOR,
-    iterator: anObject(iterator),
-    next: iterator.next
-  });
+var AsyncFromSyncIterator = function AsyncIterator(iteratorRecord) {
+  iteratorRecord.type = ASYNC_FROM_SYNC_ITERATOR;
+  setInternalState(this, iteratorRecord);
 };
 
 AsyncFromSyncIterator.prototype = defineBuiltIns(create(AsyncIteratorPrototype), {

diff --git a/packages/core-js/internals/get-async-iterator.js b/packages/core-js/internals/get-async-iterator.js
@@ -2,12 +2,13 @@ var call = require('../internals/function-call');
 var AsyncFromSyncIterator = require('../internals/async-from-sync-iterator');
 var anObject = require('../internals/an-object');
 var getIterator = require('../internals/get-iterator');
+var getIteratorDirect = require('../internals/get-iterator-direct');
 var getMethod = require('../internals/get-method');
 var wellKnownSymbol = require('../internals/well-known-symbol');
 
 var ASYNC_ITERATOR = wellKnownSymbol('asyncIterator');
 
 module.exports = function (it, usingIterator) {
   var method = arguments.length < 2 ? getMethod(it, ASYNC_ITERATOR) : usingIterator;
-  return method ? anObject(call(method, it)) : new AsyncFromSyncIterator(getIterator(it));
+  return method ? anObject(call(method, it)) : new AsyncFromSyncIterator(getIteratorDirect(getIterator(it)));
 };
diff --git a/packages/core-js/modules/esnext.async-iterator.from.js b/packages/core-js/modules/esnext.async-iterator.from.js
@@ -18,15 +18,17 @@ $({ target: 'AsyncIterator', stat: true, forced: true }, {
   from: function from(O) {
     var object = toObject(O);
     var usingIterator = getMethod(object, ASYNC_ITERATOR);
-    var iterator;
+    var iteratorRecord;
     if (usingIterator) {
-      iterator = getAsyncIterator(object, usingIterator);
-      if (isPrototypeOf(AsyncIteratorPrototype, iterator)) return iterator;
+      iteratorRecord = getIteratorDirect(getAsyncIterator(object, usingIterator));
+      if (isPrototypeOf(AsyncIteratorPrototype, iteratorRecord.iterator)) return iteratorRecord.iterator;
     }
-    if (iterator === undefined) {
+    if (iteratorRecord === undefined) {
       usingIterator = getIteratorMethod(object);
-      if (usingIterator) iterator = new AsyncFromSyncIterator(getIterator(object, usingIterator));
+      if (usingIterator) iteratorRecord = getIteratorDirect(new AsyncFromSyncIterator(
+        getIteratorDirect(getIterator(object, usingIterator))
+      ));
     }
-    return new WrapAsyncIterator(getIteratorDirect(iterator !== undefined ? iterator : object));
+    return new WrapAsyncIterator(iteratorRecord !== undefined ? iteratorRecord : getIteratorDirect(object));
   }
 });
diff --git a/packages/core-js/modules/esnext.iterator.from.js b/packages/core-js/modules/esnext.iterator.from.js
@@ -17,12 +17,12 @@ $({ target: 'Iterator', stat: true, forced: true }, {
   from: function from(O) {
     var object = toObject(O);
     var usingIterator = getIteratorMethod(object);
-    var iterator;
+    var iteratorRecord;
     if (usingIterator) {
-      iterator = getIterator(object, usingIterator);
-      if (isPrototypeOf(IteratorPrototype, iterator)) return iterator;
+      iteratorRecord = getIteratorDirect(getIterator(object, usingIterator));
+      if (isPrototypeOf(IteratorPrototype, iteratorRecord.iterator)) return iteratorRecord.iterator;
     } else {
-      iterator = object;
-    } return new IteratorProxy(getIteratorDirect(iterator));
+      iteratorRecord = getIteratorDirect(object);
+    } return new IteratorProxy(iteratorRecord);
   }
 });
diff --git a/packages/core-js/modules/esnext.iterator.to-async.js b/packages/core-js/modules/esnext.iterator.to-async.js
@@ -7,6 +7,6 @@ var getIteratorDirect = require('../internals/get-iterator-direct');
 
 $({ target: 'Iterator', proto: true, real: true, forced: true }, {
   toAsync: function toAsync() {
-    return new WrapAsyncIterator(getIteratorDirect(new AsyncFromSyncIterator(this)));
+    return new WrapAsyncIterator(getIteratorDirect(new AsyncFromSyncIterator(getIteratorDirect(this))));
   }
 });