Implement `in' for proxies.

src/objects.cc

 // Copyright 2011 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 2178 matching lines @@
   if (result->IsFound() && result->type() == HANDLER) {
     return JSProxy::cast(this)->SetPropertyWithHandler(
         key, value, attributes, strict_mode);
   } else {
     return JSObject::cast(this)->SetPropertyForResult(
         result, key, value, attributes, strict_mode);
   }
 }
 
 
+bool JSProxy::HasPropertyWithHandler(String* name_raw) {
+  Isolate* isolate = GetIsolate();
+  HandleScope scope(isolate);
+  Handle<Object> receiver(this);
+  Handle<Object> name(name_raw);
+  Handle<Object> handler(this->handler());
+
+  // Extract trap function.
+  Handle<String> trap_name = isolate->factory()->LookupAsciiSymbol("has");
+  Handle<Object> trap(v8::internal::GetProperty(handler, trap_name));

[Mads Ager (chromium), 2011/07/19 09:35:28]

I would use = instead of constructor syntax here.

+  if (trap->IsUndefined()) {
+    trap = isolate->derived_has_trap();
+  }
+
+  // Call trap function.
+  Object** args[] = { name.location() };
+  bool has_exception;
+  Handle<Object> result =
+      Execution::Call(trap, handler, ARRAY_SIZE(args), args, &has_exception);
+  if (has_exception) return Failure::Exception();
+
+  return result->ToBoolean()->IsTrue();
+}
+
+
 MUST_USE_RESULT MaybeObject* JSProxy::SetPropertyWithHandler(
     String* name_raw,
     Object* value_raw,
     PropertyAttributes attributes,
     StrictModeFlag strict_mode) {
   Isolate* isolate = GetIsolate();
   HandleScope scope(isolate);
   Handle<Object> receiver(this);
   Handle<Object> name(name_raw);
   Handle<Object> value(value_raw);
@@ skipping 9555 matching lines @@
   if (break_point_objects()->IsUndefined()) return 0;
   // Single beak point.
   if (!break_point_objects()->IsFixedArray()) return 1;
   // Multiple break points.
   return FixedArray::cast(break_point_objects())->length();
 }
 #endif
 
 
 } }  // namespace v8::internal