A few methods to disable and restore ActiveRecord in a spec helper

disable_ar_helper.rb

def disable_ar
  class << ActiveRecord::Base
    def fail_connection; fail 'Tried to access the DB'; end
    alias_method :old_connection, :connection
    alias_method :connection, :fail_connection
  end
end

def restore_ar
  class << ActiveRecord::Base
    alias_method :connection, :old_connection
  end
end