module CanCan::Ability

def authorize!(action, subject, *args)
  message = args.last.is_a?(Hash) && args.last.key?(:message) ? args.pop[:message] : nil
  if cannot?(action, subject, *args)
    message ||= unauthorized_message(action, subject)
    raise AccessDenied.new(message, action, subject, args)
  end
  subject
end