ES6: Add Object.getOwnPropertySymbols

src/v8natives.js

Index: src/v8natives.js
diff --git a/src/v8natives.js b/src/v8natives.js
index 96b88c5285c9962d479fa75d0e71031cd0c35b6c..76f64c946cd42af11b7c4dd7d5aca1b20a92d2c9 100644
--- a/src/v8natives.js
+++ b/src/v8natives.js
@@ -1037,46 +1037,41 @@ function ToNameArray(obj, trap, includeSymbols) {
 }
 
 
-// ES5 section 15.2.3.4.
-function ObjectGetOwnPropertyNames(obj) {
-  if (!IS_SPEC_OBJECT(obj)) {
-    throw MakeTypeError("called_on_non_object", ["Object.getOwnPropertyNames"]);
-  }
-  // Special handling for proxies.
-  if (%IsJSProxy(obj)) {
-    var handler = %GetHandler(obj);
-    var names = CallTrap0(handler, "getOwnPropertyNames", UNDEFINED);
-    return ToNameArray(names, "getOwnPropertyNames", false);
-  }
-
+function ObjectGetOwnPropertyKeys(obj, symbolsOnly) {
   var nameArrays = new InternalArray();
+  var filter = symbolsOnly ?
+      PROPERTY_ATTRIBUTES_STRING | PROPERTY_ATTRIBUTES_PRIVATE_SYMBOL :
+      PROPERTY_ATTRIBUTES_SYMBOLIC;
 
   // Find all the indexed properties.
 
-  // Get the local element names.
-  var localElementNames = %GetLocalElementNames(obj);
-  for (var i = 0; i < localElementNames.length; ++i) {
-    localElementNames[i] = %_NumberToString(localElementNames[i]);
-  }
-  nameArrays.push(localElementNames);
-
-  // Get names for indexed interceptor properties.
-  var interceptorInfo = %GetInterceptorInfo(obj);
-  if ((interceptorInfo & 1) != 0) {
-    var indexedInterceptorNames = %GetIndexedInterceptorElementNames(obj);
-    if (!IS_UNDEFINED(indexedInterceptorNames)) {
-      nameArrays.push(indexedInterceptorNames);
+  // Only get the local element names if we want to include string keys.
+  if (!symbolsOnly) {
+    var localElementNames = %GetLocalElementNames(obj);
+    for (var i = 0; i < localElementNames.length; ++i) {
+      localElementNames[i] = %_NumberToString(localElementNames[i]);
+    }
+    nameArrays.push(localElementNames);
+
+    // Get names for indexed interceptor properties.
+    var interceptorInfo = %GetInterceptorInfo(obj);
+    if ((interceptorInfo & 1) != 0) {
+      var indexedInterceptorNames = %GetIndexedInterceptorElementNames(obj);
+      if (!IS_UNDEFINED(indexedInterceptorNames)) {
+        nameArrays.push(indexedInterceptorNames);
+      }
     }
   }
 
   // Find all the named properties.
 
   // Get the local property names.
-  nameArrays.push(%GetLocalPropertyNames(obj, false));
+  nameArrays.push(%GetLocalPropertyNames(obj, filter));
 
   // Get names for named interceptor properties if any.
   if ((interceptorInfo & 2) != 0) {
-    var namedInterceptorNames = %GetNamedInterceptorPropertyNames(obj);
+    var namedInterceptorNames =

[rossberg, 2014/01/09 12:01:28]

Nit: obsolete line wrap

+        %GetNamedInterceptorPropertyNames(obj);
     if (!IS_UNDEFINED(namedInterceptorNames)) {
       nameArrays.push(namedInterceptorNames);
     }
@@ -1089,18 +1084,18 @@ function ObjectGetOwnPropertyNames(obj) {
   // Property names are expected to be unique strings,
   // but interceptors can interfere with that assumption.
   if (interceptorInfo != 0) {
-    var propertySet = { __proto__: null };
+    var seenKeys = { __proto__: null };
     var j = 0;
     for (var i = 0; i < propertyNames.length; ++i) {
-      if (IS_SYMBOL(propertyNames[i])) continue;
-      var name = ToString(propertyNames[i]);
-      // We need to check for the exact property value since for intrinsic
-      // properties like toString if(propertySet["toString"]) will always
-      // succeed.
-      if (propertySet[name] === true) {
-        continue;
+      var name = propertyNames[i];
+      if (symbolsOnly) {
+        if (!IS_SYMBOL(name) || IS_PRIVATE(name)) continue;
+      } else {
+        if (IS_SYMBOL(name)) continue;
+        name = ToString(name);
       }
-      propertySet[name] = true;
+      if (seenKeys[name]) continue;
+      seenKeys[name] = true;
       propertyNames[j++] = name;
     }
     propertyNames.length = j;
@@ -1110,6 +1105,22 @@ function ObjectGetOwnPropertyNames(obj) {
 }
 
 
+// ES5 section 15.2.3.4.
+function ObjectGetOwnPropertyNames(obj) {
+  if (!IS_SPEC_OBJECT(obj)) {
+    throw MakeTypeError("called_on_non_object", ["Object.getOwnPropertyNames"]);
+  }
+  // Special handling for proxies.
+  if (%IsJSProxy(obj)) {
+    var handler = %GetHandler(obj);
+    var names = CallTrap0(handler, "getOwnPropertyNames", UNDEFINED);
+    return ToNameArray(names, "getOwnPropertyNames", false);
+  }
+
+  return ObjectGetOwnPropertyKeys(obj, false);
+}
+
+
 // ES5 section 15.2.3.5.
 function ObjectCreate(proto, properties) {
   if (!IS_SPEC_OBJECT(proto) && proto !== null) {
@@ -1419,12 +1430,15 @@ function SetUpObject() {
     "getPrototypeOf", ObjectGetPrototypeOf,
     "getOwnPropertyDescriptor", ObjectGetOwnPropertyDescriptor,
     "getOwnPropertyNames", ObjectGetOwnPropertyNames,
+    // getOwnPropertySymbols is added in symbol.js.
     "is", ObjectIs,
     "isExtensible", ObjectIsExtensible,
     "isFrozen", ObjectIsFrozen,
     "isSealed", ObjectIsSealed,
     "preventExtensions", ObjectPreventExtension,
     "seal", ObjectSeal
+    // deliverChangeRecords, getNotifier, observe and unobserve are added
+    // in object-observe.js.
   ));
 }