functional test for Rails plugin, assert_template broken?

Question

I'm writing a plugin that adds a class method to ActionController::Base, so in my functional test I am creating a simple controller to test against. The example below is totally stripped down to basically do nothing. The test succeeds all the way up to assert_template, which fails.

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

Here are the results from running the above file:

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

My questions: what am I missing to allow assert_template to work? Am I requiring the correct libraries? Extending the correct TestCase class?

Answer 1

I figured it out. First, the missing template is because the view_path needs to be explicitly set in the controller under test:

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

I created a dummy erb file in test/fixtures/under_test/index.erb. That brings me back to the nil error in response_assertions.rb. Well, it looks like I need to include another test class:

require 'action_view/test_case'

Now it works.

One additional note: assert_template uses match to determine success, so in this case, assert_template 'ind' would succeed, as would assert_template 'x'.