Change Object.defineProperty to accept undefined as getters and setters and t...

src/runtime.cc

Index: src/runtime.cc
===================================================================
--- src/runtime.cc	(revision 6011)
+++ src/runtime.cc	(working copy)
@@ -3516,7 +3516,8 @@
   CONVERT_ARG_CHECKED(JSObject, obj, 0);
   CONVERT_CHECKED(String, name, args[1]);

[Lasse Reichstein, 2010/12/16 09:43:34]

This argument is not stored in a handle, so why use a handle for fun?
(In fact, this whole function seems like it should not use handles at all, since
it doesn't for most of its values).

[Rico, 2010/12/16 12:17:55]

Done.

   CONVERT_CHECKED(Smi, flag_setter, args[2]);
-  CONVERT_CHECKED(JSFunction, fun, args[3]);
+  Handle<Object> fun = args.at<Object>(3);
+  RUNTIME_ASSERT(fun->IsJSFunction() || fun->IsUndefined());
   CONVERT_CHECKED(Smi, flag_attr, args[4]);
   int unchecked = flag_attr->value();
   RUNTIME_ASSERT((unchecked & ~(READ_ONLY | DONT_ENUM | DONT_DELETE)) == 0);
@@ -3537,7 +3538,7 @@
       if (!maybe_ok->ToObject(&ok)) return maybe_ok;
     }
   }
-  return obj->DefineAccessor(name, flag_setter->value() == 0, fun, attr);
+  return obj->DefineAccessor(name, flag_setter->value() == 0, *fun, attr);
 }
 
 static MaybeObject* Runtime_DefineOrRedefineDataProperty(Arguments args) {
@@ -3572,7 +3573,7 @@
   }
 
   LookupResult result;
-  js_object->LocalLookupRealNamedProperty(*name, &result);
+  js_object->LookupRealNamedProperty(*name, &result);
 
   // Take special care when attributes are different and there is already
   // a property. For simplicity we normalize the property which enables us
@@ -3580,7 +3581,8 @@
   // map. The current version of SetObjectProperty does not handle attributes
   // correctly in the case where a property is a field and is reset with
   // new attributes.
-  if (result.IsProperty() && attr != result.GetAttributes()) {
+  if (result.IsProperty() &&
+      (attr != result.GetAttributes() || result.type() == CALLBACKS)) {
     // New attributes - normalize to avoid writing to instance descriptor
     NormalizeProperties(js_object, CLEAR_INOBJECT_PROPERTIES, 0);
     // Use IgnoreAttributes version since a readonly property may be