fix one case of built-in iterators deoptimization in V8, related #377

zloirock · Mar 27, 2018 · 546d2d8 · 546d2d8
1 parent 6fd2e8c
commit 546d2d8
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/modules/_iter-define.js b/modules/_iter-define.js
@@ -41,7 +41,7 @@ module.exports = function (Base, NAME, Constructor, next, DEFAULT, IS_SET, FORCE
       // Set @@toStringTag to native iterators
       setToStringTag(IteratorPrototype, TAG, true);
       // fix for some old engines
-      if (!LIBRARY && !has(IteratorPrototype, ITERATOR)) hide(IteratorPrototype, ITERATOR, returnThis);
+      if (!LIBRARY && typeof IteratorPrototype[ITERATOR] != 'function') hide(IteratorPrototype, ITERATOR, returnThis);
     }
   }
   // fix Array#{values, @@iterator}.name in V8 / FF