Trigger debug event on not yet caught exception in promises.

src/debug.cc

Index: src/debug.cc
diff --git a/src/debug.cc b/src/debug.cc
index b41375b825a0286c7450a9829188202cd419ec96..d3cf89543e3401813694805e19f1de517b4b2793 100644
--- a/src/debug.cc
+++ b/src/debug.cc
@@ -2628,13 +2628,15 @@ MaybeHandle<Object> Debugger::MakeBreakEvent(Handle<Object> break_points_hit) {
 
 
 MaybeHandle<Object> Debugger::MakeExceptionEvent(Handle<Object> exception,
-                                                 bool uncaught) {
+                                                 bool uncaught,
+                                                 Handle<Object> promise) {
   Handle<Object> exec_state;
   if (!MakeExecutionState().ToHandle(&exec_state)) return MaybeHandle<Object>();
   // Create the new exception event object.
   Handle<Object> argv[] = { exec_state,
                             exception,
-                            isolate_->factory()->ToBoolean(uncaught) };
+                            isolate_->factory()->ToBoolean(uncaught),
+                            promise };
   return MakeJSObject(CStrVector("MakeExceptionEvent"), ARRAY_SIZE(argv), argv);
 }
 
@@ -2664,7 +2666,9 @@ MaybeHandle<Object> Debugger::MakeScriptCollectedEvent(int id) {
 }
 
 
-void Debugger::OnException(Handle<Object> exception, bool uncaught) {
+void Debugger::OnException(Handle<Object> exception,
+                           bool uncaught,
+                           Handle<Object> promise) {
   HandleScope scope(isolate_);
   Debug* debug = isolate_->debug();
 
@@ -2688,13 +2692,26 @@ void Debugger::OnException(Handle<Object> exception, bool uncaught) {
 
   // Clear all current stepping setup.
   debug->ClearStepping();
+
+  // Determine event;
+  DebugEvent event;
+  if (promise.is_null()) {
+    event = v8::Exception;
+    promise = isolate_->factory()->undefined_value();

[aandrey, 2014/04/24 11:04:59]

maybe set undefined to promise by default instead of null? then this line will
go away naturally

[Yang, 2014/04/24 11:13:48]

Done.

+  } else {
+    event = v8::UncaughtExceptionInPromise;
+  }
+
   // Create the event data object.
   Handle<Object> event_data;
   // Bail out and don't call debugger if exception.
-  if (!MakeExceptionEvent(exception, uncaught).ToHandle(&event_data)) return;
+  if (!MakeExceptionEvent(
+          exception, uncaught, promise).ToHandle(&event_data)) {
+    return;
+  }
 
   // Process debug event.
-  ProcessDebugEvent(v8::Exception, Handle<JSObject>::cast(event_data), false);
+  ProcessDebugEvent(event, Handle<JSObject>::cast(event_data), false);
   // Return to continue execution from where the exception was thrown.
 }