在 RSpec 中测试创建操作时没有得到准确的输出答案

【问题标题】：Not getting the exact output when testing Create action in RSpec在 RSpec 中测试创建操作时没有得到准确的输出
【发布时间】：2016-11-18 11:55:09
【问题描述】：

我正在使用模拟和存根进行测试，但在控制器中测试 create 操作时无法获得所需的输出。

失败的测试：

describe 'authenticated user' do
  let(:user) { instance_double(User) }
  before do
    allow(controller).to receive(:current_user) { user }
    allow(controller).to receive(:authenticate_user!) { true }
  end

  describe "POST create" do
    let(:achievement_params) { { title: "title" } }
    let(:create_achievement) { instance_double(CreateAchievement) }

    before do
      allow(CreateAchievement).to receive(:new) { create_achievement }
    end

    it 'sends create message to CreateAchievement' do
    expect(CreateAchievement).to receive(:new).with(achievement_params, user)
    expect(create_achievement).to receive(:create)
    post :create, achievement: achievement_params

    end
  end
end

控制器中的create 操作

def create
  service = CreateAchievement.new(params[:achievement], current_user)
  service.create
  render nothing: true
end

错误：

  1) AchievementsController authenticated user POST create sends create message to CreateAchivement
 Failure/Error: expect(CreateAchievement).to receive(:new).with(achievement_params, user)

   #<CreateAchievement (class)> received :new with unexpected arguments
     expected: ({:title=>"title"}, #<InstanceDouble(User) (anonymous)>)
          got: (<ActionController::Parameters {"title"=>"title"} permitted: false>, #<InstanceDouble(User) (anonymous)>)
   Diff:
   @@ -1,2 +1,3 @@
   -[{:title=>"title"}, #<InstanceDouble(User) (anonymous)>]
   +[<ActionController::Parameters {"title"=>"title"} permitted: false>,
   + #<InstanceDouble(User) (anonymous)>]

【问题讨论】：

标签： ruby-on-rails rspec stub rspec-mocks

【解决方案1】：

那是因为您需要在控制器中“允许”您的 POST 值：

def achievement_params
  params.require(:achievement).permit(:title)
end

然后，从您的控制器操作中调用它：

service = CreateAchievement.new(achievement_params, current_user)

【讨论】：

【解决方案2】：

您需要允许控制器中的参数：

private

def achievement_params
   params.require(:achievement).permit(:title)
end

更改您的创建方法以接收这些参数，而不是 params[:achievement]：

def create
  service = CreateAchievement.new(achievement_params, current_user)
  service.create
  render body: nil
end

在您的规范中，您需要使用允许title 参数的ActionController::Parameters.new 方法创建参数：

let(:achievement_params) { ActionController::Parameters.new('title': 'title').permit(:title) }

如下：

describe 'POST create' do
  let(:achievement_params) { ActionController::Parameters.new('title': 'title').permit(:title) }
  let(:create_achievement) {instance_double(CreateAchievement)}

  before do
    allow(CreateAchievement).to receive(:new) {create_achievement}
  end

  it 'sends create message to CreateAchievement' do
    expect(CreateAchievement).to receive(:new).with(achievement_params, user)
    expect(create_achievement).to receive(:create)

    post :create, params: {achievement: achievement_params }
  end
end

【讨论】：