Upgrading from rails 4.0 to 4.2

Ruby on Rails
8

@acandael I am changing the files mentioned in the RailsDiff website between 4.0.0 and 4.1.0 and one of the changes is -Railsdiff::Application.initialize! to +Rails.application.initialize! however when I do this changing Rails to my app name I get undefined method 'application' for Aas:module

Any ideas?

Thanks