v8::TryCatch should cancel the scheduled exception on Reset.

src/api.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/api.h"
 
 #include <string.h>  // For memcpy, strlen.
 #ifdef V8_USE_ADDRESS_SANITIZER
 #include <sanitizer/asan_interface.h>
 #endif  // V8_USE_ADDRESS_SANITIZER
@@ skipping 1805 matching lines @@
 
 
 v8::TryCatch::TryCatch()
     : isolate_(i::Isolate::Current()),
       next_(isolate_->try_catch_handler()),
       is_verbose_(false),
       can_continue_(true),
       capture_message_(true),
       rethrow_(false),
       has_terminated_(false) {
-  Reset();
+  ResetInternal();
   // Special handling for simulators which have a separate JS stack.
   js_stack_comparable_address_ =
       reinterpret_cast<void*>(v8::internal::SimulatorStack::RegisterCTryCatch(
           GetCurrentStackPosition()));
   isolate_->RegisterTryCatchHandler(this);
 }
 
 
 v8::TryCatch::~TryCatch() {
   DCHECK(isolate_ == i::Isolate::Current());
@@ skipping 91 matching lines @@
   if (HasCaught() && !message->IsTheHole()) {
     return v8::Utils::MessageToLocal(i::Handle<i::Object>(message, isolate_));
   } else {
     return v8::Local<v8::Message>();
   }
 }
 
 
 void v8::TryCatch::Reset() {
   DCHECK(isolate_ == i::Isolate::Current());
+  if (!rethrow_ && HasCaught() && isolate_->has_scheduled_exception()) {
+    // If an exception was caught but is still scheduled because no API call
+    // promoted it, then it is canceled to prevent it from being propagated.
+    // Note that this will not cancel termination exceptions.
+    isolate_->CancelScheduledExceptionFromTryCatch(this);
+  }
+  ResetInternal();
+}
+
+
+void v8::TryCatch::ResetInternal() {
   i::Object* the_hole = isolate_->heap()->the_hole_value();
   exception_ = the_hole;
   message_obj_ = the_hole;
   message_script_ = the_hole;
   message_start_pos_ = 0;
   message_end_pos_ = 0;
 }
 
 
 void v8::TryCatch::SetVerbose(bool value) {
@@ skipping 5675 matching lines @@
   Isolate* isolate = reinterpret_cast<Isolate*>(info.GetIsolate());
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 } }  // namespace v8::internal