Example class used for http://www.reddit.com/r/rails/comments/3ajld9/writing_clean_code_with_rubocop_and_atom_linters/csdxzoi

smelly_application_controller.rb

class ApplicationController < ActionController::Base
  # Prevent CSRF attacks by raising an exception.
  # For APIs, you may want to use :null_session instead.
  protect_from_forgery with: :exception

  @public_actions = [:new, :create, :validate, :show, :index]

  before_filter :require_login, except: @public_actions

  def not_authenticated
    redirect_to login_path, notice: "You must log in first to access this"
  end

  protected

  def render_error(error_code=403, layout=false)
    render(:file => File.join(Rails.root, "public/#{error_code}.html"), :status => error_code, :layout => layout)
  end
end