Don't clear exception pending message if we have externally TryCatch and finally on top of stack.

src/isolate.cc

Index: src/isolate.cc
diff --git a/src/isolate.cc b/src/isolate.cc
index 3542b994ff3338ffd3860b763f49b4730dfe6d54..a5c859c6948c809208618fed9556ec1d0f15a48c 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -1144,7 +1144,7 @@ void Isolate::DoThrow(Object* exception, MessageLocation* location) {
 }
 
 
-bool Isolate::IsExternallyCaught() {
+bool Isolate::HasExternalTryCatch() {
   ASSERT(has_pending_exception());
 
   if ((thread_local_top()->catcher_ == NULL) ||
@@ -1154,10 +1154,11 @@ bool Isolate::IsExternallyCaught() {
     return false;

[Yang, 2014/06/02 15:21:16]

Can we simply return an expression?

return (thread_local_top()->catcher_ != NULL) && (try_catch_handler() ==
thread_local_top()->catcher_);

   }
 
-  if (!is_catchable_by_javascript(pending_exception())) {

[vsevik, 2014/06/02 15:31:28]

Looking at this once again I think this check is still needed.

Unfortunately you will probably need to extract another function. :(

-    return true;
-  }
+  return true;
+}
 
+
+bool Isolate::IsFinallyOnTop() {
   // Get the address of the external handler so we can compare the address to
   // determine which one is closer to the top of the stack.
   Address external_handler_address =
@@ -1177,18 +1178,18 @@ bool Isolate::IsExternallyCaught() {
       StackHandler::FromAddress(Isolate::handler(thread_local_top()));
   while (handler != NULL && handler->address() < external_handler_address) {
     ASSERT(!handler->is_catch());
-    if (handler->is_finally()) return false;
+    if (handler->is_finally()) return true;
 
     handler = handler->next();
   }
 
-  return true;
+  return false;
 }
 
 
 void Isolate::ReportPendingMessages() {
   ASSERT(has_pending_exception());
-  PropagatePendingExceptionToExternalTryCatch();
+  bool canClearMessage = PropagatePendingExceptionToExternalTryCatch();

[Yang, 2014/06/02 15:21:16]

please name this 'can_clear_message' instead.

 
   HandleScope scope(this);
   if (thread_local_top_.pending_exception_ ==
@@ -1215,7 +1216,8 @@ void Isolate::ReportPendingMessages() {
       }
     }
   }
-  clear_pending_message();
+  if (canClearMessage)
+    clear_pending_message();

[Yang, 2014/06/02 15:21:16]

no line break here.

 }
 
 
@@ -1722,13 +1724,16 @@ void Isolate::InitializeThreadLocal() {
 }
 
 
-void Isolate::PropagatePendingExceptionToExternalTryCatch() {
+bool Isolate::PropagatePendingExceptionToExternalTryCatch() {
   ASSERT(has_pending_exception());
 
-  bool external_caught = IsExternallyCaught();
-  thread_local_top_.external_caught_exception_ = external_caught;
+  bool has_external_try_catch = HasExternalTryCatch();
+  bool is_finally_on_top  = IsFinallyOnTop();
 
-  if (!external_caught) return;
+  bool should_propagate_now = has_external_try_catch && !is_finally_on_top;
+  thread_local_top_.external_caught_exception_ = should_propagate_now;
+
+  if (!should_propagate_now) return !has_external_try_catch;
 
   if (thread_local_top_.pending_exception_ ==
              heap()->termination_exception()) {
@@ -1745,13 +1750,14 @@ void Isolate::PropagatePendingExceptionToExternalTryCatch() {
     handler->has_terminated_ = false;
     handler->exception_ = pending_exception();
     // Propagate to the external try-catch only if we got an actual message.
-    if (thread_local_top_.pending_message_obj_->IsTheHole()) return;
+    if (thread_local_top_.pending_message_obj_->IsTheHole()) return true;
 
     handler->message_obj_ = thread_local_top_.pending_message_obj_;
     handler->message_script_ = thread_local_top_.pending_message_script_;
     handler->message_start_pos_ = thread_local_top_.pending_message_start_pos_;
     handler->message_end_pos_ = thread_local_top_.pending_message_end_pos_;
   }
+  return true;
 }