Return browserify bundle instead of generating the bundle

I've made the change and fixed a bunch of tests, but there are some that I couldn't. They are all using run.js in order to run the command line version of mochify. The problem resides in the return code of the operation, it is always 0-ok. I believe it is because what will fail now is the bundle but not the process itself. 

Can you please have a look and let me know how will be the way to fix it? i believe it is in run.js
Thanks
F