Implement function proxies (except for their use as constructors).

src/execution.cc

Index: src/execution.cc
diff --git a/src/execution.cc b/src/execution.cc
index bdbdca81bb7cfcdf5cf34316ce4d541abab5fed6..51dc6bafaf69021acefad5c071a5b52f98f59362 100644
--- a/src/execution.cc
+++ b/src/execution.cc
@@ -149,12 +149,27 @@ Handle<Object> Execution::Call(Handle<Object> callable,
                                Handle<Object> receiver,
                                int argc,
                                Object*** args,
-                               bool* pending_exception) {
+                               bool* pending_exception,
+                               bool convert_receiver) {
   if (!callable->IsJSFunction()) {
     callable = TryGetFunctionDelegate(callable, pending_exception);
     if (*pending_exception) return callable;
   }
   Handle<JSFunction> func = Handle<JSFunction>::cast(callable);
+
+  // In non-strict mode, convert receiver.
+  if (convert_receiver && !receiver->IsJSReceiver() &&
+      !func->shared()->native() && !func->shared()->strict_mode()) {
+    if (receiver->IsUndefined() || receiver->IsNull()) {
+      Object* global = func->context()->global()->global_receiver();
+      // Is there a way to get the proper global object if func is a builtin?

[Kevin Millikin (Chromium), 2011/09/12 14:42:47]

I guess I'm not sure what is proper.  isolate()->global_context()->builtins() is
the builtins object, isolate()->global_object()->global_receiver() is the global
receiver of the current context.

[rossberg, 2011/09/12 15:17:25]

Ah, thanks, the latter is what I was looking for, but somehow missed. Because
func->context()->global()->g_r() gives me the JSBuiltin object if func happens
to be a builtin, which would not be good (and breaks one of the tests).

Now, the only thing that still puzzles me is how that very logic is used in the
generated FunctionApply builtin without causing the same issue...

+      if (!global->IsJSBuiltinsObject()) receiver = Handle<Object>(global);
+    } else {
+      receiver = ToObject(receiver, pending_exception);
+    }
+    if (*pending_exception) return callable;
+  }
+
   return Invoke(false, func, receiver, argc, args, pending_exception);
 }
 
@@ -210,10 +225,17 @@ Handle<Object> Execution::GetFunctionDelegate(Handle<Object> object) {
   // If you return a function from here, it will be called when an
   // attempt is made to call the given object as a function.
 
+  // If object is a function proxies, get its handler. Iterate if necessary.
+  Object* fun = *object;
+  while (fun->IsJSFunctionProxy()) {
+    fun = JSFunctionProxy::cast(fun)->call_trap();
+  }
+  if (fun->IsJSFunction()) return Handle<Object>(fun);
+
   // Objects created through the API can have an instance-call handler
   // that should be used when calling the object as a function.
-  if (object->IsHeapObject() &&
-      HeapObject::cast(*object)->map()->has_instance_call_handler()) {
+  if (fun->IsHeapObject() &&
+      HeapObject::cast(fun)->map()->has_instance_call_handler()) {
     return Handle<JSFunction>(
         isolate->global_context()->call_as_function_delegate());
   }
@@ -227,10 +249,17 @@ Handle<Object> Execution::TryGetFunctionDelegate(Handle<Object> object,
   ASSERT(!object->IsJSFunction());
   Isolate* isolate = Isolate::Current();
 
+  // If object is a function proxies, get its handler. Iterate if necessary.
+  Object* fun = *object;
+  while (fun->IsJSFunctionProxy()) {
+    fun = JSFunctionProxy::cast(fun)->call_trap();
+  }
+  if (fun->IsJSFunction()) return Handle<Object>(fun);
+
   // Objects created through the API can have an instance-call handler
   // that should be used when calling the object as a function.
-  if (object->IsHeapObject() &&
-      HeapObject::cast(*object)->map()->has_instance_call_handler()) {
+  if (fun->IsHeapObject() &&
+      HeapObject::cast(fun)->map()->has_instance_call_handler()) {
     return Handle<JSFunction>(
         isolate->global_context()->call_as_function_delegate());
   }
@@ -253,10 +282,17 @@ Handle<Object> Execution::GetConstructorDelegate(Handle<Object> object) {
   // If you return a function from here, it will be called when an
   // attempt is made to call the given object as a constructor.
 
+  // If object is a function proxies, get its handler. Iterate if necessary.
+  Object* fun = *object;
+  while (fun->IsJSFunctionProxy()) {
+    fun = JSFunctionProxy::cast(fun)->call_trap();
+  }
+  if (fun->IsJSFunction()) return Handle<Object>(fun);
+
   // Objects created through the API can have an instance-call handler
   // that should be used when calling the object as a function.
-  if (object->IsHeapObject() &&
-      HeapObject::cast(*object)->map()->has_instance_call_handler()) {
+  if (fun->IsHeapObject() &&
+      HeapObject::cast(fun)->map()->has_instance_call_handler()) {
     return Handle<JSFunction>(
         isolate->global_context()->call_as_constructor_delegate());
   }
@@ -274,10 +310,17 @@ Handle<Object> Execution::TryGetConstructorDelegate(
   // If you return a function from here, it will be called when an
   // attempt is made to call the given object as a constructor.
 
+  // If object is a function proxies, get its handler. Iterate if necessary.
+  Object* fun = *object;
+  while (fun->IsJSFunctionProxy()) {
+    fun = JSFunctionProxy::cast(fun)->call_trap();
+  }
+  if (fun->IsJSFunction()) return Handle<Object>(fun);
+
   // Objects created through the API can have an instance-call handler
   // that should be used when calling the object as a function.
-  if (object->IsHeapObject() &&
-      HeapObject::cast(*object)->map()->has_instance_call_handler()) {
+  if (fun->IsHeapObject() &&
+      HeapObject::cast(fun)->map()->has_instance_call_handler()) {
     return Handle<JSFunction>(
         isolate->global_context()->call_as_constructor_delegate());
   }
@@ -553,7 +596,7 @@ Handle<Object> Execution::ToDetailString(Handle<Object> obj, bool* exc) {
 
 
 Handle<Object> Execution::ToObject(Handle<Object> obj, bool* exc) {
-  if (obj->IsJSObject()) return obj;
+  if (obj->IsSpecObject()) return obj;
   RETURN_NATIVE_CALL(to_object, 1, { obj.location() }, exc);
 }