Make exception thrown via v8 public API propagate to v8::TryCatch as JS thrown exceptions do.

src/top.cc

Index: src/top.cc
diff --git a/src/top.cc b/src/top.cc
index 62850b13e0e742f50d18736c364f3c118390ae73..c8c56a266510f251a86530b370b4ea0db9138e22 100644
--- a/src/top.cc
+++ b/src/top.cc
@@ -70,6 +70,7 @@ void ThreadLocalTop::Initialize() {
   int id = Isolate::Current()->thread_manager()->CurrentId();
   thread_id_ = (id == 0) ? ThreadManager::kInvalidId : id;
   external_caught_exception_ = false;
+  in_exception_reporting_ = false;
   failed_access_check_callback_ = NULL;
   save_context_ = NULL;
   catcher_ = NULL;
@@ -796,55 +797,38 @@ bool Isolate::IsExternallyCaught() {
 
 void Isolate::ReportPendingMessages() {
   ASSERT(has_pending_exception());
+  PropagatePendingExceptionToExternalTryCatch();
+
   // If the pending exception is OutOfMemoryException set out_of_memory in
   // the global context.  Note: We have to mark the global context here
   // since the GenerateThrowOutOfMemory stub cannot make a RuntimeCall to
   // set it.
-  bool external_caught = IsExternallyCaught();
-  thread_local_top()->external_caught_exception_ = external_caught;
-  HandleScope scope(this);
-  if (thread_local_top()->pending_exception_ ==
-      Failure::OutOfMemoryException()) {
+  HandleScope scope;
+  if (thread_local_top_.pending_exception_ == Failure::OutOfMemoryException()) {
     context()->mark_out_of_memory();
-  } else if (thread_local_top()->pending_exception_ ==
-             heap_.termination_exception()) {
-    if (external_caught) {
-      try_catch_handler()->can_continue_ = false;
-      try_catch_handler()->exception_ = heap_.null_value();
-    }
+  } else if (thread_local_top_.pending_exception_ ==
+             heap()->termination_exception()) {
+    // Do nothing: if needed, the exception has been already propagated to
+    // v8::TryCatch.
   } else {
-    // At this point all non-object (failure) exceptions have
-    // been dealt with so this shouldn't fail.
-    Object* pending_exception_object = pending_exception()->ToObjectUnchecked();
-    Handle<Object> exception(pending_exception_object);
-    thread_local_top()->external_caught_exception_ = false;
-    if (external_caught) {
-      try_catch_handler()->can_continue_ = true;
-      try_catch_handler()->exception_ = thread_local_top()->pending_exception_;
-      if (!thread_local_top()->pending_message_obj_->IsTheHole()) {
-        try_catch_handler()->message_ =
-            thread_local_top()->pending_message_obj_;
-      }
-    }
-    if (thread_local_top()->has_pending_message_) {
-      thread_local_top()->has_pending_message_ = false;
-      if (thread_local_top()->pending_message_ != NULL) {
-        MessageHandler::ReportMessage(thread_local_top()->pending_message_);
-      } else if (!thread_local_top()->pending_message_obj_->IsTheHole()) {
-        Handle<Object> message_obj(thread_local_top()->pending_message_obj_);
-        if (thread_local_top()->pending_message_script_ != NULL) {
-          Handle<Script> script(thread_local_top()->pending_message_script_);
-          int start_pos = thread_local_top()->pending_message_start_pos_;
-          int end_pos = thread_local_top()->pending_message_end_pos_;
+    if (thread_local_top_.has_pending_message_) {
+      thread_local_top_.has_pending_message_ = false;
+      if (thread_local_top_.pending_message_ != NULL) {
+        MessageHandler::ReportMessage(thread_local_top_.pending_message_);
+      } else if (!thread_local_top_.pending_message_obj_->IsTheHole()) {
+        HandleScope scope;
+        Handle<Object> message_obj(thread_local_top_.pending_message_obj_);
+        if (thread_local_top_.pending_message_script_ != NULL) {
+          Handle<Script> script(thread_local_top_.pending_message_script_);
+          int start_pos = thread_local_top_.pending_message_start_pos_;
+          int end_pos = thread_local_top_.pending_message_end_pos_;
           MessageLocation location(script, start_pos, end_pos);
-          MessageHandler::ReportMessage(&location, message_obj);
+          MessageHandler::ReportMessage(this, &location, message_obj);
         } else {
-          MessageHandler::ReportMessage(NULL, message_obj);
+          MessageHandler::ReportMessage(this, NULL, message_obj);
         }
       }
     }
-    thread_local_top()->external_caught_exception_ = external_caught;
-    set_pending_exception(*exception);
   }
   clear_pending_message();
 }
@@ -856,6 +840,9 @@ void Isolate::TraceException(bool flag) {
 
 
 bool Isolate::OptionalRescheduleException(bool is_bottom_call) {
+  ASSERT(has_pending_exception());
+  PropagatePendingExceptionToExternalTryCatch();
+
   // Allways reschedule out of memory exceptions.
   if (!is_out_of_memory()) {
     bool is_termination_exception =
@@ -968,7 +955,7 @@ char* Isolate::RestoreThread(char* from) {
   memcpy(reinterpret_cast<char*>(thread_local_top()), from,
          sizeof(ThreadLocalTop));
   // This might be just paranoia, but it seems to be needed in case a
-  // thread_local_ is restored on a separate OS thread.
+  // thread_local_top_ is restored on a separate OS thread.
 #ifdef USE_SIMULATOR
 #ifdef V8_TARGET_ARCH_ARM
   thread_local_top()->simulator_ = Simulator::current(this);