Rubyonrails 为什么我的 RSpec 没有加载 Devise：：Test：：ControllerHelpers

我正在使用Rails 5，并设计了3.5.1.

阅读一本关于创建/测试API的好书，该API使用Desive身份验证.它是在Rails 5之前编写的，所以我 Select 不使用新的仅api版本.

这是我的测试...

#/spec/controllers/api/v1/users_controller_spec.rb    

require 'rails_helper'

describe Api::V1::UsersController, :type => :controller do
    before(:each) { request.headers['Accept'] = "application/vnd.marketplace.v1" }
    describe "GET #show" do
        before(:each) do
            @user = FactoryGirl.create :user
            get :show, params: {id: @user.id}, format: :json
        end
        it "returns the information about a reporter on a hash" do
            user_response = JSON.parse(response.body, symbolize_names: true)
            expect(user_response[:email]).to eql @user.email
        end
        it { should respond_with 200 }
    end
end

这是一个完全出乎意料的RSpec错误

Devise::MissingWarden:
       Devise could not find the `Warden::Proxy` instance on your request environment.
       Make sure that your application is loading Devise and Warden as expected and that the `Warden::Manager` middleware is present in your middleware stack.
       If you are seeing this on one of your tests, ensure that your tests are either executing the Rails middleware stack or that your tests are using the `Devise::Test::ControllerHelpers` module to inject the `request.env['warden']` object for you.

所以我来这里-http://www.rubydoc.info/gems/devise/Devise/Test/ControllerHelpers

and tried this -> include Devise::Test::ControllerHelpers

这没用，因为文件controller_helpers.rb不在我的项目中

我错过了什么？

谢谢