Question

This question is NOT about how to test controllers in a rails app.

Developing a gem I want to test if my gem integrates in a rails controller.
So running rspec in the gem root is outside the rails environment.

Now how do I write say a controller test which can use the rspec controller example group helpers like get or post?

IN particular if I set a metatag :type => :controller on an example group , how does rspec set up the rails environment and how can i hook into that in order to say set up routes, etc.

I’d rather not have to set up an entire rails app skeleton mostly empty. But I cannot even find info on how to do that. What is best practice to test a gem integrating to rails app or multiple frameworks.

These sources came closest to what I am after:
Test (with RSpec) a controller outside of a Rails environment
but this is for test unit.
http://railsware.com/blog/2012/01/07/testing-gem-integration-with-multiple-ruby-frameworks/
but this is for capybara which directly hooks in a rails app class.

thanks all

Answer 1

Below is a nice minimal example of a rails controller integration test from a gem.
my_gem. Assume that you are in a gem root with simple rspec setup (say with rspec --init). Then spec/rails_controller_integration_spec.rb will look like this.

rspec/rails does the necessary requires, among them rspec/rails/example which sets up example group types based on metatags. The metatag :type => :controller drives the inclusion of the proper group module RSpec::Rails::ControllerExampleGroup which provides you with all the goodies of rails controller specing as well as all the goodies of ActionController::TestCase like get/post.

Hope this helps.

What I still don’t get is how the Rails environment gets assigned. In particular what if I would like to set up two apps TestTailsApp1 and TestTailsApp2. any advice?

require 'spec_helper'
require 'my_gem'

require 'rails'
require 'action_controller/railtie' # allows ActionController::Base
# crucial part here:
require 'rspec/rails'
# note that require 'rspec-rails' does not work

module TestRailsApp
  class Application < Rails::Application
    # app config here
    # config.secret_token = '572c86f5ede338bd8aba8dae0fd3a326aabababc98d1e6ce34b9f5'
    # routes.draw do
    #   resources :models
    # end
  end

  class ApplicationController < ActionController::Base
    # setup
  end

end

describe 'My gem' do

  context "in a Rails controller", :type => :controller do

    controller(TestRailsApp::ApplicationController) do
      extend(RSpec::Rails::ControllerExampleGroup::BypassRescue)
      # example-specific setup for anonymous controller
      # https://www.relishapp.com/rspec/rspec-rails/docs/controller-specs/anonymous-controller
      def index
      end
    end

    before(:each) do
      # request needs to be setup to avoid path setting error
      @request = ActionController::TestRequest.new
    end

    describe "#index" do
      it "works" do
        get :index
        response.body.should == 'index content'
      end
    end
  end

end