Make formatting error message side-effect-free.

src/runtime.cc

 // Copyright 2012 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 4220 matching lines @@
   }
 
   return Runtime::ForceSetObjectProperty(isolate,
                                          js_object,
                                          name,
                                          obj_value,
                                          attr);
 }
 
 
+// Return property without being observable by accessors or interceptors.
+RUNTIME_FUNCTION(MaybeObject*, Runtime_GetDataProperty) {
+  ASSERT(args.length() == 2);
+  CONVERT_ARG_HANDLE_CHECKED(JSObject, object, 0);
+  CONVERT_ARG_HANDLE_CHECKED(String, key, 1);
+  LookupResult lookup(isolate);
+  object->LookupRealNamedProperty(*key, &lookup);
+  if (!lookup.IsProperty()) return isolate->heap()->undefined_value();

[Sven Panne, 2012/11/12 10:14:00]

With the change below, this can change to ...!lookup.IsFound()...

+  switch (lookup.type()) {
+    case NORMAL:
+      return lookup.holder()->GetNormalizedProperty(&lookup);
+    case FIELD:
+      return lookup.holder()->FastPropertyAt(lookup.GetFieldIndex());
+    case CONSTANT_FUNCTION:
+      return lookup.GetConstantFunction();
+    default:

[Sven Panne, 2012/11/12 10:14:00]

Please explicitly list all PropertyTypes. We should never use a default case for
enums, because it makes it impossible to find the places which should change
when the corresponding enum changes in an automatic way.

+      return isolate->heap()->undefined_value();
+  }
+}
+
+
 MaybeObject* Runtime::SetObjectProperty(Isolate* isolate,
                                         Handle<Object> object,
                                         Handle<Object> key,
                                         Handle<Object> value,
                                         PropertyAttributes attr,
                                         StrictModeFlag strict_mode) {
   SetPropertyMode set_mode = attr == NONE ? SET_PROPERTY : DEFINE_PROPERTY;
   HandleScope scope(isolate);
 
   if (object->IsUndefined() || object->IsNull()) {
@@ skipping 9113 matching lines @@
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(Heap::kNoGCFlags,
                                        "Runtime::PerformGC");
   }
 }
 
 
 } }  // namespace v8::internal