Strict mode delete.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 5003b4f8c30b76d10c0bfeb29b3ed7c0c9736ce8..8f70c724fea103a87d8c5eddd87b9ccb5ddac13f 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -1399,7 +1399,7 @@ MaybeObject* JSObject::AddProperty(String* name,
   if (!map()->is_extensible()) {
     Handle<Object> args[1] = {Handle<String>(name)};
     return Top::Throw(*Factory::NewTypeError("object_not_extensible",
-                                               HandleVector(args, 1)));
+                                             HandleVector(args, 1)));
   }
   if (HasFastProperties()) {
     // Ensure the descriptor array does not get too big.
@@ -2620,7 +2620,14 @@ MaybeObject* JSObject::DeleteElement(uint32_t index, DeleteMode mode) {
       NumberDictionary* dictionary = element_dictionary();
       int entry = dictionary->FindEntry(index);
       if (entry != NumberDictionary::kNotFound) {
-        return dictionary->DeleteProperty(entry, mode);
+        Object* result = dictionary->DeleteProperty(entry, mode);

[Martin Maly, 2011/02/14 05:15:22]

DeleteProperty is a wrong place to report the error because it is missing the
necessary data to report good error, and it is called from other places which
don't even have the relevant information.
Checking for false_value() for strict mode delete felt cleanest.

[Mads Ager (chromium), 2011/02/14 10:27:24]

I think that makes sense. Could you add a comment in the body of the if
statement that deleting non-configurable properties in strict mode should throw
exceptions?

[Martin Maly, 2011/02/14 21:46:51]

Done.

+        if (mode == STRICT_DELETION && result == Heap::false_value()) {
+          HandleScope scope;
+          Handle<Object> i = Factory::NewNumberFromUint(index);
+          Handle<Object> args[2] = { i, Handle<Object>(this) };
+          return Top::Throw(*Factory::NewTypeError("strict_delete_property",
+                                                   HandleVector(args, 2)));
+        }
       }
       break;
     }
@@ -2659,6 +2666,12 @@ MaybeObject* JSObject::DeleteProperty(String* name, DeleteMode mode) {
     if (!result.IsProperty()) return Heap::true_value();
     // Ignore attributes if forcing a deletion.
     if (result.IsDontDelete() && mode != FORCE_DELETION) {
+      if (mode == STRICT_DELETION) {
+        HandleScope scope;
+        Handle<Object> args[2] = { Handle<Object>(name), Handle<Object>(this) };
+        return Top::Throw(*Factory::NewTypeError("strict_delete_property",
+                                                 HandleVector(args, 2)));
+      }
       return Heap::false_value();
     }
     // Check for interceptor.
@@ -9345,7 +9358,7 @@ Object* Dictionary<Shape, Key>::DeleteProperty(int entry,
                                                JSObject::DeleteMode mode) {
   PropertyDetails details = DetailsAt(entry);
   // Ignore attributes if forcing a deletion.
-  if (details.IsDontDelete() && mode == JSObject::NORMAL_DELETION) {
+  if (details.IsDontDelete() && mode != JSObject::FORCE_DELETION) {
     return Heap::false_value();
   }
   SetEntry(entry, Heap::null_value(), Heap::null_value(), Smi::FromInt(0));