Change the D8 JavaScript debugger to fully use the JSON protocol....

src/d8-debug.cc

 // Copyright 2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 28 matching lines @@
                       Handle<Value> data) {
   HandleScope scope;
 
   // Check for handled event.
   if (event != Break && event != Exception && event != AfterCompile) {
     return;
   }
 
   TryCatch try_catch;
 
+  // Get the toJSONProtocol function on the event and get the JSON format.
+  Local<String> to_json_fun_name = String::New("toJSONProtocol");
+  Local<Function> to_json_fun =
+      Function::Cast(*event_data->Get(to_json_fun_name));
+  Local<Value> event_json = to_json_fun->Call(event_data, 0, NULL);
+  if (try_catch.HasCaught()) {
+    Shell::ReportException(&try_catch);
+    return;
+  }
+
   // Print the event details.
-  Handle<String> details = Shell::DebugEventToText(event_data);
+  Handle<String> details =
+      Shell::DebugEventToText(Handle<String>::Cast(event_json));
   if (details->Length() == 0) {
     // Empty string is used to signal not to process this event.
     return;
   }
   String::Utf8Value str(details);
   printf("%s\n", *str);
 
   // Get the debug command processor.
   Local<String> fun_name = String::New("debugCommandProcessor");
   Local<Function> fun = Function::Cast(*exec_state->Get(fun_name));
@@ skipping 60 matching lines @@
     if (text_str.length() > 0) {
       printf("%s\n", *text_str);
     }
     running =
         response_details->Get(String::New("running"))->ToBoolean()->Value();
   }
 }
 
 
 }  // namespace v8