Why debug won't work in this situation?

I'm using the gem called omniauth-facebook, with which I succeeded at implementing of facebook login auth.
It looks fine but it won't pass data of whole object to the view.
It should show array things in the case when using 'debug'

But it shows this somehow :(

--- 
...

Why it won't work as usual? How can I fix it?
I just want to check inside of data as usual.

Controller

@auth = request.env["omniauth.auth"]

View

<%= debug @auth %>