Implement Object.keys for proxies.

src/v8natives.js

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 290 matching lines @@
   if (receiver == null && !IS_UNDETECTABLE(receiver)) {
     receiver = %GlobalReceiver(global);
   }
   return %LookupAccessor(ToObject(receiver), ToString(name), SETTER);
 }
 
 
 function ObjectKeys(obj) {
   if (!IS_SPEC_OBJECT(obj))
     throw MakeTypeError("obj_ctor_property_non_object", ["keys"]);
+  if (%IsJSProxy(obj)) {
+    var handler = %GetHandler(obj);
+    var keys = handler.keys;
+    if (IS_UNDEFINED(keys)) keys = DerivedKeysTrap;
+    var names = keys.call(handler);

[Mads Ager (chromium), 2011/07/12 13:28:19]

Do you want to rely on Function.prototype.call here or do you want to use
%_CallFunction(handler, keys)?

[rossberg, 2011/07/13 10:11:52]

Done, here and in a few other places. (Btw, who picked the argument order of
that built-in??)

[Mads Ager (chromium), 2011/07/13 10:17:25]

I don't remember. I would have preferred having the function first... :-)

+    return ToStringArray(names);
+  }
   return %LocalKeys(obj);
 }
 
 
 // ES5 8.10.1.
 function IsAccessorDescriptor(desc) {
   if (IS_UNDEFINED(desc)) return false;
   return desc.hasGetter() || desc.hasSetter();
 }
 
@@ skipping 1136 matching lines @@
 // ----------------------------------------------------------------------------
 
 function SetupFunction() {
   InstallFunctions($Function.prototype, DONT_ENUM, $Array(
     "bind", FunctionBind,
     "toString", FunctionToString
   ));
 }
 
 SetupFunction();