How to test Rails 3 Engines with Cucumber & Rspec? - ruby-on-rails

I apologize if this question is slightly subjective... I am trying to figure out the best way to test Rails 3 Engines with Cucumber & Rspec. In order to test the engine a rails 3 app is necessary. Here is what I am currently doing:
Add a rails test app to the root of the gem (myengine) by running: rails new /myengine/rails_app
Add Cucumber to /myengine/rails_app/features as you would in a normal Rails app
Require the Rails Engine Gem (using :path=>"/myengine") in /myengine/rails_app/Gemfile
Add spec to the root directory of the gem: /myengine/spec
Include the fixtures in /myengine/spec/fixtures and I add the following to my cuc env.rb:
env.rb:
Fixtures.reset_cache
fixtures_folder = File.join(Rails.root, 'spec', 'fixtures')
fixtures = Dir[File.join(fixtures_folder, '*.yml')].map {|f| File.basename(f, '.yml') }
Fixtures.create_fixtures(fixtures_folder, fixtures)
Do you see any problems with setting it up like this? The tests run fine, but I am a bit hesitant to put the features inside the test rails app. I originally tried putting the features in the root of the gem and I created the test rails app inside features/support, but for some reason my engine would not initialize when I ran the tests, even though I could see the app loading everything else when cuc ran.
If anyone is working with Rails Engines and is using cuc and rspec for testing, I would be interested to hear your setup.
**UPDATE
I changed my setup a bit since I wrote this question. I decided to get rid of the spec directory under the root of the engine. Now I just create a rails app named "test_app" and setup cuc and rspec inside that app like I would normally do in a rails app. Then I include the gem like I did in step #3 above. Since the engine is a sub-app, I guess its just best to test it like it was a normal rails app. I am still interested in hearing if anyone has a different setup.

Rails 3.1 (will) generate a pretty good scaffold for engines. I'd recommend using RVM to create a new gemset called edge and switch to it:
rvm gemset create edge
rvm use #edge
Then install edge rails:
git clone git://github.com/rails/rails.git
cd rails
rake install
From there, you can follow Piotr Sarnacki's mountable app tutorial, replacing calls such as:
bundle exec ./bin/rails plugin new ../blog --edge --mountable
With simply:
rails plugin new blog --mountable --full
The mountable option makes the application mountable, whilst the full option makes it an engine with tests already built-in. To test the engine, this generator generates a folder in test called dummy which contains a small Rails application. You can see how this is loaded in test/test_helper.rb.
Then it's up to you to massage the data to do what it needs to in order to work. I would recommend copying over the cucumber files from a standard rails g cucumber:install into the project and then messing about with it until it works. I've done this once before so I know it's possible, but I cannot find the code right now.
Let me know how you go.

I'll explain how I did it using as example the following gem: https://github.com/skozlov/netzke-core
The testing application. It is in netzke-core/test/rails_app. This app can be run independently, so I can also use it for manual testing or for playing around with new features if I like.
In order for the testing app to load the gem itself, I have the following in application.rb:
$:.unshift File.expand_path('../../../../lib', __FILE__)
require 'netzke-core'
Cucumber features. They are in netzke-core/features. In env.rb I have:
require File.expand_path(File.dirname(__FILE__) + '/../../test/rails_app/config/environment')
... which will load the testing application before executing the features.
Specs. These are in netzke-core/spec. In spec_helper.rb I have the following:
require File.expand_path("../../test/rails_app/config/environment", __FILE__)
... which will load the testing application before running the specs.
Running tests. This setup lets me run the tests from the root of the gem:
cucumber features
and
rspec spec
Factory Girl. Not for this particular gem, but I'm normally using factory_girl instead of fixtures (see, for example, a similar setup in https://github.com/skozlov/netzke-basepack).

A bit late to the party, but here is my strategy:
Generating the rails plugin in 3.2:
rails plugin new blog --mountable --full
This creates test/dummy, containing the dummy rails app
Add the specs to spec
Move the dummy folder to spec (and optionally get rid of the other testfiles)
Adapt specs/spec_helper.rb so it includes
require File.expand_path("../.../config/environment", __FILE__)
instead of
require File.expand_path("../dummy/config/environment", __FILE__)
Execute rails g cucumber:install. It will generate features folder a.o.
Add
ENV["RAILS_ROOT"] ||= File.expand_path(File.dirname(__FILE__) + '/../../spec/dummy')
before
require 'cucumber/rails'
in features/support/env.rb
Now you have features and spec in the root of you project, while the dummy rails app is neatly tucked away under spec/dummy

Related

How to test a gem that depends on Rails and uses Rails commands

I'm making a gem that executes Rails commands (rails g model Item for example). When I use it in a Rails project, everything works. The problem is testing it in development outside of a Rails project.
I'm using cucumber with aruba to test if CLI commands execute the proper rails commands and generate the expected files. Unfortunately, when I try to test the behaviour it fails because there are no rails files and the commands require to be run inside of a Rails project in order to work.
I have added a rails dependency to the gemspec:
Gem::Specification.new do |spec|
spec.add_development_dependency 'rails', '~> 5.2.4'
end
I've thought about creating a new rails project on test start and then deleting it after the tests run, but that seems highly inconvenient. Is there a better way to do this?
A technique we use for WickedPDF is in the default rake task, before we run the tests, is to delete & generate a full Rails application in a gitignored subdirectory of the gem.
As a high-level simplified example of this Rakefile, it looks something like this:
Rakefile
require 'rake'
require 'rake/testtask'
# This gets run when you run `bin/rake` or `bundle exec rake` without specifying a task.
task :default => [:generate_dummy_rails_app, :test]
desc 'generate a rails app inside the test directory to get access to it'
task :generate_dummy_rails_app do
if File.exist?('test/dummy/config/environment.rb')
FileUtils.rm_r Dir.glob('test/dummy/')
end
system('rails new test/dummy --database=sqlite3')
system('touch test/dummy/db/schema.rb')
FileUtils.cp 'test/fixtures/database.yml', 'test/dummy/config/'
FileUtils.rm_r Dir.glob('test/dummy/test/*') # clobber existing tests
end
desc 'run tests in the test directory, which includes the generated rails app'
Rake::TestTask.new(:test) do |t|
t.libs << 'lib'
t.libs << 'test'
t.pattern = 'test/**/*_test.rb'
t.verbose = true
end
Then, in test/test_helper.rb, we require the generated Rails app, which loads Rails itself and it's environment:
test/test_helper.rb
ENV['RAILS_ENV'] = 'test'
require File.expand_path('../dummy/config/environment.rb', __FILE__)
require 'test/unit' # or possibly rspec/minispec
# Tests can go here, or other test files can require this file to have the Rails environment available to them.
# Some tests may need to copy assets/fixtures/controllers into the dummy app before being run. That can happen here, or in your test setup.
You could skip parts of Rails that aren't needed by customizing the command that generates the app. For example, your gem may not need a database at all or a lot of things by default, so you command could be customized for a simpler app. Something like this maybe:
system("rails new test/dummy --skip-active-record \
--skip-active-storage --skip-action-cable --skip-webpack-install \
--skip-git --skip-sprockets --skip-javascript --skip-turbolinks")
In the WickedPDF project, we wanted to test across a wide range of "default" Rails installs, so we don't customize the command much, but that may generate much more than what you need to test some generator tasks.
WickedPDF also tests against multiple versions of Rails with TravisCI and multiple Gemfiles, but this could also be accomplished with the Appraisal gem that Luke suggested in this thread.
Check out Thoughbot's Appraisal gem:
Appraisal integrates with bundler and rake to test your library against different versions of dependencies in repeatable scenarios called "appraisals."
Here is a guide on how to set it up, including setting up a micro Rails app within your tests dir.

How to uninstall minitest from Rails

I'm using Ruby 2.2.0p0, and Rails 4.2.0. The Rails application is currently defaulting to using minitest, even though there's no testing gems mentioned in the Gemfile. For example, I have rake test in my rake tasks, and a test folder.
I can see how to install RSpec-rails. But what, if anything, do I need to do to uninstall minitest?
The only thing the RSpec-Rails README has is
Once installed, RSpec will generate spec files instead of Test::Unit
test files when commands like rails generate model and rails generate
controller are used.
It seems to me that in your case it not necessary to uninstall minitest, just add rspec to your Gemfile and start using it. However I recommend you to make RSpec as your default test framework.
Just add to config/application.rb next line:
config.generators.test_framework :rspec
That's it. Now Rails knows that you use RSpec and when you use Rails generators, it will add appropriate RSpec templete files, not Minitest ones. If you have test folder in your application (it's used by Minitest and Test::Unit) you can delete it now.

How to require fixture_builder in cucumber?

I have a Rails 4.1 project that uses RSpec and Cucumber.
I've recently added fixture_builder.
fixture_builder.rb includes logic to rebuild fixtures any time the file changes.
This works fine for RSpec with require 'fixture_builder' in spec_helper.rb.
However, when running Cucumber tests fixture_builder.rb is not called, so fixtures are not updated if any changes have been made to fixture_builder.rb.
Is there an equivalent config file like spec_helper.rb for Cucumber?
By default, Cucumber loads all *.rb files in the same directory as the feature(s) it's running and all subdirectories of that directory, so you can put your require in any file you want in any of those directories.
The conventional thing to do is to put 'support' code like require in features/support/env.rb, or in another file in features/support if your env.rb gets too big.
The cucumber-rails gem provides a generator that sets up Cucumber to work with Rails. If you haven't already, install the gem and run
rails g cucumber:install
to create features/support/env.rb and the rest of the usual Rails + Cucumber setup.

How do you revert back Test::Unit when you skipped it in the install process?

When I first learned Rails, the tutorial suggested I use RSpec. After evaluating my code, Test::Unit seems like a better fit. But my application is already built up, how do I revert the command:
rails new my_app --skip-test-unit
without destroying/redoing my application?
Uncomment the following line in config/application.rb
require "rails/test_unit/railtie"
and remove rspec from Gemfile.
You will probably have to make a test directory. As well, you will need to add all the relevant details and files from here for all those other things that weren't automagically generated. Check out the latest for Rails testing here:
http://guides.rubyonrails.org/testing.html
mkdir test
cd test
mkdir fixtures functional integration
and so on to make up for the non-generated files.
This page helped to get the answer:
Ruby on Rails: Switch from test_unit to rspec

Writing tests for Rails plugins

I'm working on a plugin for Rails that would add limited in-memory caching to ActiveRecord's finders. The functionality itself is mature enough, but I can't for the life of me get unit tests to work with the plugin.
I now have under vendor/plugins/my_plugin/test/my_plugin_test.rb a standard subclass of ActiveSupport::TestCase with a couple of basic tests. I try running 'rake test' from the plugin directory, and I have confirmed that this task loads the ruby file with the test case, but it doesn't actually run any of the tests.
I followed the Rails plugin guide (http://guides.rubyonrails.org/plugins.html) where applicable, but it seems to be horribly outdated (it suggests things that Rails now do automatically, etc.)
The only output I get is this:
Kakadu:ingenious_record adam$ rake test
(in /Users/adam/Sites/1_PRK/vendor/plugins/ingenious_record)
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby -Ilib:lib:test "/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/rake-0.8.3/lib/rake/rake_test_loader.rb" "test/ingenious_record_test.rb"
The simplest test case looks like this:
require 'test_helper'
require 'active_record'
class IngeniousRecordTest < ActiveSupport::TestCase
test "example" do
assert false
end
end
This should definitely produce at least some output, and the only test in that file should produce a failed assertion.
Any ideas what I could do to get Rails to run my tests?
I test my plugins using the Engines plugin's rake tasks:
rake test:plugins:all PLUGIN=myplugin
I'm sure you can do it without Engines, but it is an option. Recent versions of Rails (I'm still on 2.2.2) have Engines support integrated.
Apparently there is a little problem with rails 2.2.3, as it does not include the 'test/unit' package/file in plugins.
In order to fix your plugin problems, just add the following to the top of your test_helper.rb file:
require 'test/unit'
Found it as a ticket at lighthouse.

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