plataformatec/simple_form — pull request #417 by nyjt (2012-01-25 14:16:00+00:00)
Title: Mongoid compatibility improvement in belongs_to case 

(no more: undefined method `options' for #)

In belongs_to case only :collection => Products.all is not help. :collection option is also necessary now, but not enough. This modification is help. I tried it with Mongoid 2.4.3 and mongoid 3.0.0 (master branch). This little modification made more compatible simple_form with mongoid and may be with others.