Use GetProperty for getting elements.

src/elements.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_ELEMENTS_H_
 #define V8_ELEMENTS_H_
 
 #include "src/elements-kind.h"
 #include "src/heap/heap.h"
 #include "src/isolate.h"
@@ skipping 30 matching lines @@
       Handle<JSObject> holder,
       uint32_t key) {
     return HasElement(holder, key, handle(holder->elements()));
   }
 
   // Returns the element with the specified key or undefined if there is no such
   // element. This method doesn't iterate up the prototype chain.  The caller
   // can optionally pass in the backing store to use for the check, which must
   // be compatible with the ElementsKind of the ElementsAccessor. If
   // backing_store is NULL, the holder->elements() is used as the backing store.
-  MUST_USE_RESULT virtual MaybeHandle<Object> Get(
-      Handle<Object> receiver,
-      Handle<JSObject> holder,
-      uint32_t key,
-      Handle<FixedArrayBase> backing_store) = 0;
+  virtual Handle<Object> Get(Handle<JSObject> holder, uint32_t key,
+                             Handle<FixedArrayBase> backing_store) = 0;
 
-  MUST_USE_RESULT inline MaybeHandle<Object> Get(
-      Handle<Object> receiver,
-      Handle<JSObject> holder,
-      uint32_t key) {
-    return Get(receiver, holder, key, handle(holder->elements()));
+  inline Handle<Object> Get(Handle<JSObject> holder, uint32_t key) {
+    return Get(holder, key, handle(holder->elements()));
   }
 
   // Returns an element's attributes, or ABSENT if there is no such
   // element. This method doesn't iterate up the prototype chain.  The caller
   // can optionally pass in the backing store to use for the check, which must
   // be compatible with the ElementsKind of the ElementsAccessor. If
   // backing_store is NULL, the holder->elements() is used as the backing store.
-  MUST_USE_RESULT virtual PropertyAttributes GetAttributes(
-      Handle<JSObject> holder,
-      uint32_t key,
-      Handle<FixedArrayBase> backing_store) = 0;
+  virtual PropertyAttributes GetAttributes(JSObject* holder, uint32_t key,
+                                           FixedArrayBase* backing_store) = 0;
 
-  MUST_USE_RESULT inline PropertyAttributes GetAttributes(
-      Handle<JSObject> holder,
-      uint32_t key) {
-    return GetAttributes(holder, key, handle(holder->elements()));
+  inline PropertyAttributes GetAttributes(Handle<JSObject> holder,
+                                          uint32_t key) {
+    return GetAttributes(*holder, key, holder->elements());
   }
 
   // Returns an element's accessors, or NULL if the element does not exist or
   // is plain. This method doesn't iterate up the prototype chain.  The caller
   // can optionally pass in the backing store to use for the check, which must
   // be compatible with the ElementsKind of the ElementsAccessor. If
   // backing_store is NULL, the holder->elements() is used as the backing store.
-  MUST_USE_RESULT virtual MaybeHandle<AccessorPair> GetAccessorPair(
-      Handle<JSObject> holder,
-      uint32_t key,
+  virtual MaybeHandle<AccessorPair> GetAccessorPair(
+      Handle<JSObject> holder, uint32_t key,
       Handle<FixedArrayBase> backing_store) = 0;
 
-  MUST_USE_RESULT inline MaybeHandle<AccessorPair> GetAccessorPair(
-      Handle<JSObject> holder,
-      uint32_t key) {
+  inline MaybeHandle<AccessorPair> GetAccessorPair(Handle<JSObject> holder,
+                                                   uint32_t key) {
     return GetAccessorPair(holder, key, handle(holder->elements()));
   }
 
   // Modifies the length data property as specified for JSArrays and resizes the
   // underlying backing store accordingly. The method honors the semantics of
   // changing array sizes as defined in EcmaScript 5.1 15.4.5.2, i.e. array that
   // have non-deletable elements can only be shrunk to the size of highest
   // element that is non-deletable.
   MUST_USE_RESULT virtual MaybeHandle<Object> SetLength(
       Handle<JSArray> holder,
@@ skipping 48 matching lines @@
       int copy_size) = 0;
 
   inline void CopyElements(
       Handle<JSObject> from_holder,
       Handle<FixedArrayBase> to,
       ElementsKind from_kind) {
     CopyElements(
       *from_holder, 0, from_kind, to, 0, kCopyToEndAndInitializeToHole);
   }
 
-  MUST_USE_RESULT virtual MaybeHandle<FixedArray> AddElementsToFixedArray(
+  virtual Handle<FixedArray> AddElementsToFixedArray(
       Handle<JSObject> receiver, Handle<FixedArray> to,
       FixedArray::KeyFilter filter) = 0;
 
   // Returns a shared ElementsAccessor for the specified ElementsKind.
   static ElementsAccessor* ForKind(ElementsKind elements_kind) {
     DCHECK(static_cast<int>(elements_kind) < kElementsKindCount);
     return elements_accessors_[elements_kind];
   }
 
   static ElementsAccessor* ForArray(Handle<FixedArrayBase> array);
@@ skipping 17 matching lines @@
   // specified in JavaScript to access the element. In most implementations,
   // keys are equivalent to indexes, and GetKeyForIndex returns the same value
   // it is passed. In the NumberDictionary ElementsAccessor, GetKeyForIndex maps
   // the index to a key using the KeyAt method on the NumberDictionary.
   virtual uint32_t GetKeyForIndex(FixedArrayBase* backing_store,
                                   uint32_t index) = 0;
   virtual uint32_t GetIndexForKey(FixedArrayBase* backing_store,
                                   uint32_t key) = 0;
   virtual PropertyDetails GetDetails(FixedArrayBase* backing_store,
                                      uint32_t index) = 0;
+  virtual bool HasIndex(FixedArrayBase* backing_store, uint32_t key) = 0;
 
  private:
   static ElementsAccessor** elements_accessors_;
   const char* name_;
 
   DISALLOW_COPY_AND_ASSIGN(ElementsAccessor);
 };
 
 void CheckArrayAbuse(Handle<JSObject> obj, const char* op, uint32_t key,
                      bool allow_appending = false);
 
 MUST_USE_RESULT MaybeHandle<Object> ArrayConstructInitializeElements(
     Handle<JSArray> array,
     Arguments* args);
 
 } }  // namespace v8::internal
 
 #endif  // V8_ELEMENTS_H_