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..cdea005829fb4e1fec14d4402272592cb58138d5 100644
--- a/src/execution.cc
+++ b/src/execution.cc
@@ -149,12 +149,28 @@ 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()) {
+      // Careful, func->context()->global()->global_receiver() gives
+      // the JSBuiltinsObject if func is a builtin. Not what we want here.
+      receiver =
+          Handle<Object>(func->GetIsolate()->global()->global_receiver());
+    } else {
+      receiver = ToObject(receiver, pending_exception);
+    }
+    if (*pending_exception) return callable;
+  }
+
   return Invoke(false, func, receiver, argc, args, pending_exception);
 }
 
@@ -210,10 +226,17 @@ 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 +250,17 @@ 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 +283,17 @@ 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 +311,17 @@ 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 +597,7 @@ 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);
 }