Question

我正在关注railstutorial by Michael Hartl，并且我不明白 第5章 中未通过测试的原因。这本书使用了minitest框架，但我决定使用RSpec。为此，我删除了测试文件夹，并在我的Gemfile中包含了rspec-rails，然后运行了bundle install和rails g rspec:install来生成我的spec文件夹。但是，有些测试我觉得使用minitest语法很方便，例如static_pages_controller_spec.rb文件中的assert_select。以下是我的spec文件的样子：

require "rails_helper"

RSpec.describe StaticPagesController, type: :controller do
  describe "GET #home" do
    it "returns http success" do
      get :home
      expect(response).to have_http_status(:success)
    end
    it "should have the right title" do
      get :home
      assert_select "title", "Ruby on Rails Tutorial Sample App"
    end
  end

  describe "GET #help" do
    it "returns http success" do
      get :help
      expect(response).to have_http_status(:success)
    end
    it "should have the right title" do
      get :help
      assert_select "title", "Help | Ruby on Rails Tutorial Sample App"
    end
  end

  describe "GET #about" do
    it "returns http success" do
      get :about
      expect(response).to have_http_status(:success)
    end
    it "should have the right title" do
      get "about"
      assert_select "title", "About | Ruby on Rails Tutorial Sample App"
    end
  end
end

当我使用RSpec运行测试时，这就是我得到的失败错误：

StaticPagesController GET #home should have the right title
 Failure/Error: assert_select "title", "Ruby on Rails Tutorial Sample App"

 NoMethodError:
   undefined method `document' for nil:NilClass
# ./spec/controllers/static_pages_controller_spec.rb:11:in `block (3 levels)
in <top (required)>'

每个失败的测试中都会出现相同的错误消息(No Method error)。

我该如何解决？有什么我做错了。

Answer 1

此错误的原因是RSpec默认情况下不会为控制器规范呈现视图。您可以为特定的规范组启用视图呈现，如下所示：

describe FooController, type: :controller do
  render_views

  # write your specs
end

或者您可以通过在RSpec配置中的某处添加它来全局启用它：

RSpec.configure do |config|
  config.render_views
end

有关详细信息，请参阅https://www.relishapp.com/rspec/rspec-rails/v/2-6/docs/controller-specs/render-views。

Answer 2

问题是assert_selected是一个MiniTest构造，而你正在使用RSpec。您将需要使用RSpec机制来期待视图内容https://relishapp.com/rspec/rspec-rails/v/3-4/docs/view-specs/view-spec或将capybara添加到您的Gemfile并使用capybara匹配器：https://gist.github.com/them0nk/2166525

未定义的方法＆＃39;文件＆＃39; for nil：使用rspec运行Rails-tutorial时的NilClass

2 个答案: