ES6: Add Object.getOwnPropertySymbols

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 43a047e78c0cd80c179a3c476c919f6251475362..6b9435476b35e81f4030f92c2ea9057037ec5f9b 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -5911,6 +5911,19 @@ bool JSReceiver::IsSimpleEnum() {
 }
 
 
+static bool FilterKey(Object* key, PropertyAttributes filter) {
+  if (key->IsSymbol()) {

[rossberg, 2013/12/18 16:50:12]

I would prefer to turn this inside out and do the filter checks first and the
(more expensive) instance type checks only if necessary.

[arv (Not doing code reviews), 2013/12/18 18:07:12]

Done.

However, these filters are not mutually exclusive so I can either call IsSymbol
once for each case or I could do it once by adding another bitmask check.

+    if (filter & SYMBOLIC) return true;
+    if ((filter & PRIVATE_SYMBOL) && Symbol::cast(key)->is_private()) {
+      return true;
+    }
+  } else {
+    if (filter & STRING) return true;
+  }
+  return false;
+}
+
+
 int Map::NumberOfDescribedProperties(DescriptorFlag which,
                                      PropertyAttributes filter) {
   int result = 0;
@@ -5920,7 +5933,7 @@ int Map::NumberOfDescribedProperties(DescriptorFlag which,
       : NumberOfOwnDescriptors();
   for (int i = 0; i < limit; i++) {
     if ((descs->GetDetails(i).attributes() & filter) == 0 &&
-        ((filter & SYMBOLIC) == 0 || !descs->GetKey(i)->IsSymbol())) {
+        !FilterKey(descs->GetKey(i), filter)) {
       result++;
     }
   }
@@ -13551,7 +13564,7 @@ void JSObject::GetLocalPropertyNames(
     DescriptorArray* descs = map()->instance_descriptors();
     for (int i = 0; i < real_size; i++) {
       if ((descs->GetDetails(i).attributes() & filter) == 0 &&
-          ((filter & SYMBOLIC) == 0 || !descs->GetKey(i)->IsSymbol())) {
+          !FilterKey(descs->GetKey(i), filter)) {
         storage->set(index++, descs->GetKey(i));
       }
     }
@@ -15653,7 +15666,7 @@ int Dictionary<Shape, Key>::NumberOfElementsFilterAttributes(
   for (int i = 0; i < capacity; i++) {
     Object* k = HashTable<Shape, Key>::KeyAt(i);
     if (HashTable<Shape, Key>::IsKey(k) &&
-        ((filter & SYMBOLIC) == 0 || !k->IsSymbol())) {
+        !FilterKey(k, filter)) {
       PropertyDetails details = DetailsAt(i);
       if (details.IsDeleted()) continue;
       PropertyAttributes attr = details.attributes();