module ActionController::TestCase::Behavior::ClassMethods

def controller_class
  if current_controller_class = self._controller_class
    current_controller_class
  else
    self.controller_class = determine_default_controller_class(name)
  end
end

def controller_class=(new_class)
  prepare_controller_class(new_class) if new_class
  self._controller_class = new_class
end

def determine_default_controller_class(name)
  name.sub(/Test$/, '').safe_constantize
end

def prepare_controller_class(new_class)
  new_class.send :include, ActionController::TestCase::RaiseActionExceptions
end

def tests(controller_class)
  case controller_class
  when String, Symbol
    self.controller_class = "#{controller_class.to_s.underscore}_controller".camelize.constantize
  when Class
    self.controller_class = controller_class
  else
    raise ArgumentError, "controller class must be a String, Symbol, or Class"
  end
end