ruby-on-rails - Rails 插件的功能测试，assert_template 损坏了吗？

Question

我正在编写一个向 ActionController::Base 添加类方法的插件，因此在我的功能测试中，我创建了一个简单的 Controller 来进行测试。下面的示例被完全精简为基本上什么都不做。测试一直成功到 assert_template，但失败了。

require 'rubygems'
require 'test/unit'
require 'active_support'
require 'active_support/test_case'
require 'action_controller'
require 'action_controller/test_process'

class UnderTestController < ActionController::Base
  def index; end
end
ActionController::Routing::Routes.draw {|map| map.resources :under_test }

class MyPluginTest < ActionController::TestCase
  def setup
    @controller = UnderTestController.new
    @request    = ActionController::TestRequest.new
    @response   = ActionController::TestResponse.new
  end

  test "should render the correct template" do
    get :index
    assert_template :index  # everything works except this assert
  end
end

下面是运行上述文件的结果:

Loaded suite /Users/jjulian/sandbox/vendor/plugins/my_plugin/test/my_plugin_test
Started
E 
Finished in 0.014567 seconds.

  1) Error:
test_should_render_the_correct_template(MyPluginTest):
NoMethodError: undefined method `[]' for nil:NilClass
method assert_template in response_assertions.rb at line 103
method clean_backtrace in test_case.rb at line 114
method assert_template in response_assertions.rb at line 100
method test_should_render_the_correct_template in so_test.rb at line 22
method __send__ in setup_and_teardown.rb at line 62
method run in setup_and_teardown.rb at line 62

1 tests, 0 assertions, 0 failures, 1 errors

我的问题:为了让 assert_template 起作用，我错过了什么？我需要正确的库吗？扩展正确的 TestCase 类？

Answer 1

我想通了。首先，缺少模板是因为 view_path 需要在被测 Controller 中显式设置:

before_filter {|c| c.prepend_view_path(File.join(File.dirname(__FILE__), 'fixtures')) }

我在 test/fixtures/under_test/index.erb 中创建了一个虚拟 erb 文件。这让我回到了 response_assertions.rb 中的 nil 错误。好吧，看来我需要包含另一个测试类:

require 'action_view/test_case'

现在可以了。

一个补充说明:assert_template 使用 match 来确定成功，所以在这种情况下，assert_template 'ind' 会成功，assert_template 'x'。