module RSpec::Rails::ControllerExampleGroup::ClassMethods

def controller(base_class = nil, &body)
  if RSpec.configuration.infer_base_class_for_anonymous_controllers?
    base_class ||= controller_class
  end
  base_class ||= defined?(ApplicationController) ? ApplicationController : ActionController::Base
  new_controller_class = Class.new(base_class) do
    def self.name
      root_controller = defined?(ApplicationController) ? ApplicationController : ActionController::Base
      if superclass == root_controller || superclass.abstract?
        "AnonymousController"
      else
        superclass.name
      end
    end
  end
  new_controller_class.class_exec(&body)
  (class << self; self; end).__send__(:define_method, :controller_class) { new_controller_class }
  before do
    @orig_routes = routes
    resource_name = if @controller.respond_to?(:controller_name)
                      @controller.controller_name.to_sym
                    else
                      :anonymous
                    end
    resource_path = if @controller.respond_to?(:controller_path)
                      @controller.controller_path
                    else
                      resource_name.to_s
                    end
    resource_module = resource_path.rpartition('/').first.presence
    resource_as = 'anonymous_' + resource_path.tr('/', '_')
    self.routes = ActionDispatch::Routing::RouteSet.new.tap do |r|
      r.draw do
        resources resource_name,
                  as: resource_as,
                  module: resource_module,
                  path: resource_path
      end
    end
  end
  after do
    self.routes  = @orig_routes
    @orig_routes = nil
  end
end