Teach JSReceiver::GetKeys() how to include symbols

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index b6c40d67fe8a64c13d4f7b44779e47281956a306..80d00f69e398cdc5b5fe8c16f4bc4bd4c3de8d78 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -6831,8 +6831,9 @@ void KeyAccumulator::Grow() {
 }
 
 
-MaybeHandle<FixedArray> JSReceiver::GetKeys(Handle<JSReceiver> object,
-                                            KeyCollectionType type) {
+MaybeHandle<FixedArray> JSReceiver::GetKeys(
+    Handle<JSReceiver> object, KeyCollectionType type,
+    IncludeSymbolNamedProperties include_symbols) {
   USE(ContainsOnlyValidKeys);
   Isolate* isolate = object->GetIsolate();
   KeyAccumulator accumulator(isolate);
@@ -6890,33 +6891,46 @@ MaybeHandle<FixedArray> JSReceiver::GetKeys(Handle<JSReceiver> object,
       DCHECK(ContainsOnlyValidKeys(accumulator.GetKeys()));
     }
 
-    // We can cache the computed property keys if access checks are
-    // not needed and no interceptors are involved.
-    //
-    // We do not use the cache if the object has elements and
-    // therefore it does not make sense to cache the property names
-    // for arguments objects.  Arguments objects will always have
-    // elements.
-    // Wrapped strings have elements, but don't have an elements
-    // array or dictionary.  So the fast inline test for whether to
-    // use the cache says yes, so we should not create a cache.
-    bool cache_enum_keys =
-        ((current->map()->GetConstructor() != *arguments_function) &&
-         !current->IsJSValue() && !current->IsAccessCheckNeeded() &&
-         !current->HasNamedInterceptor() && !current->HasIndexedInterceptor());
-    // Compute the property keys and cache them if possible.
-
-    Handle<FixedArray> enum_keys =
-        JSObject::GetEnumPropertyKeys(current, cache_enum_keys);
-    accumulator.AddKeys(enum_keys, FixedArray::ALL_KEYS);
+    if (include_symbols == SKIP_SYMBOLS) {
+      // We can cache the computed property keys if access checks are
+      // not needed and no interceptors are involved.
+      //
+      // We do not use the cache if the object has elements and
+      // therefore it does not make sense to cache the property names
+      // for arguments objects.  Arguments objects will always have
+      // elements.
+      // Wrapped strings have elements, but don't have an elements
+      // array or dictionary.  So the fast inline test for whether to
+      // use the cache says yes, so we should not create a cache.
+      bool cache_enum_keys =
+          ((current->map()->GetConstructor() != *arguments_function) &&
+           !current->IsJSValue() && !current->IsAccessCheckNeeded() &&
+           !current->HasNamedInterceptor() &&
+           !current->HasIndexedInterceptor());
+      // Compute the property keys and cache them if possible.
+      Handle<FixedArray> enum_keys =
+          JSObject::GetEnumPropertyKeys(current, cache_enum_keys);
+      accumulator.AddKeys(enum_keys, FixedArray::ALL_KEYS);
+    } else {
+      DCHECK(include_symbols == INCLUDE_SYMBOLS);
+      PropertyAttributes filter =
+          static_cast<PropertyAttributes>(DONT_ENUM | PRIVATE_SYMBOL);
+      Handle<FixedArray> property_keys = isolate->factory()->NewFixedArray(
+          current->NumberOfOwnProperties(filter));
+      current->GetOwnPropertyNames(*property_keys, 0, filter);

[Camillo Bruni, 2015/09/29 16:27:20]

Not sure how much work this would be, but essentially you could add the property
names directly to the accumulator and avoid the property_keys temporary. Might
be harder for the dict paths in GetOwnPropertyNames.

[Jakob Kummerow, 2015/09/30 13:59:30]

I'm leaving that to you :-)

+      accumulator.AddKeys(property_keys, FixedArray::ALL_KEYS);
+    }
     DCHECK(ContainsOnlyValidKeys(accumulator.GetKeys()));
 
-    // Add the non-symbol property keys from the interceptor.
+    // Add the property keys from the interceptor.
     if (current->HasNamedInterceptor()) {
       Handle<JSObject> result;
       if (JSObject::GetKeysForNamedInterceptor(
               current, object).ToHandle(&result)) {
-        accumulator.AddKeys(result, FixedArray::NON_SYMBOL_KEYS);
+        FixedArray::KeyFilter filter = include_symbols == SKIP_SYMBOLS
+                                           ? FixedArray::NON_SYMBOL_KEYS
+                                           : FixedArray::ALL_KEYS;
+        accumulator.AddKeys(result, filter);
       }
       DCHECK(ContainsOnlyValidKeys(accumulator.GetKeys()));
     }
@@ -13832,13 +13846,8 @@ int JSObject::GetOwnPropertyNames(FixedArray* storage, int index,
 
 
 int JSObject::NumberOfOwnElements(PropertyAttributes filter) {
-  return GetOwnElementKeys(NULL, filter);
-}
-
-
-int JSObject::NumberOfEnumElements() {
   // Fast case for objects with no elements.
-  if (!IsJSValue() && HasFastObjectElements()) {
+  if (!IsJSValue() && HasFastElements()) {
     uint32_t length = IsJSArray() ?
         static_cast<uint32_t>(
             Smi::cast(JSArray::cast(this)->length())->value()) :
@@ -13846,6 +13855,11 @@ int JSObject::NumberOfEnumElements() {
     if (length == 0) return 0;
   }
   // Compute the number of enumerable elements.
+  return GetOwnElementKeys(NULL, filter);
+}
+
+
+int JSObject::NumberOfEnumElements() {
   return NumberOfOwnElements(static_cast<PropertyAttributes>(DONT_ENUM));
 }