Rails Engine (4.0.2) routing methods fail in controllers using MiniTest

Question

I am able to successfully call actions in my engine controllers from my ActionController::TestCase derived test with:

test "should get new" do
  get :new, {'form_id' => '1-2', use_route: :engine_controllers}
  assert_response :success
  assert_match(/Hello World/, @response.body)
end

But I am getting an error when referencing a routing method within the controller or view. Specifically, from the following routes:

    Routes for FormEngine::Engine:
            GET  /:form_id(.:format)         form_engine/submissions#new
submissions POST /:form_id(.:format)         form_engine/submissions#create
            POST /payment_info/:id(.:format) form_engine/submissions#update
 submission GET  /submissions/:id(.:format)  form_engine/submissions#show

These are intentionally not restful routes.

When I reference submissions_path or form_engine.submissions_path I get the following error in my test run:

ActionController::UrlGenerationError: No route matches {:controller=>"form_engine/submissions", :action=>"create"} missing required keys: [:form_id]

I do not get this error when running the server. I get the path expected: /form_engine/1-2

I have traced the problem down to the fact that when run as a server request.path_parameters has the :form_id in it, but in the test case run request.path_parameters is empty.

In a non-engine controller test case, request.path_parameters correctly has the path parameters. From what I can tell, in

actionpack (4.0.2) lib/action_controller/test_case.rb:189:
extra_keys = routes.extra_keys(parameters)

ends up listing all of the parameters as extra keys and get added to non_path_parameters. I have not figured out what is misfiring in routes.extra_keys so that :form_id is being listed as an extra key.

I'm guessing that routes is losing the use_route or something like that.

I found a somewhat similar question, but I'm not sure it is actually related: Rails 3.2 Engines - routes not working in test cases. So far there hasn't been a satisfactory answer to it.

If anyone can see an obvious mistake I am making or knows of a workaround, I would love to hear it.

Thanks in advance.

Answer 1

I found the solution (for me) in the Ruby on Rails Engine Guide

module MyEngineName
  class FooControllerTest < ActionController::TestCase
    setup do
      @routes = Engine.routes
    end

    def test_index
      get :index
      ...
    end
  end
end