Rails%203%20In%20Action

480 CHAPTER 17 Engines
This is really helpful for Test::Unit, but you can also cannibalize it for your RSpec.
Let’s create a spec directory and put in it a spec /spec_helper.rb, which contains similar
content to the test/test_helper.rb file:
# Configure Rails Environment
ENV["RAILS_ENV"] = "test"
require File.expand_path("../dummy/config/environment.rb",
require 'rspec/rails'
__FILE__)
Rails.backtrace_cleaner.remove_silencers! B Remove backtrace cleaner
# Load support files
Dir["#{File.dirname(__FILE__)}/support/**/*.rb"].each { |f| require f }
It’s about identical, except you’ve replaced the require to rails/test_help with
rspec/rails. This spec/spec_helper.rb file will be loaded by RSpec when you run
your tests.
One thing to note is the line Rails.backtrace_cleaner.remove_silencers! B.
Rails has an automated backtrace cleaner, which it uses to shorten the resulting backtrace
from errors so that it’s easier to track down. You don’t need this silencing going
on in your tests, and so you can remove it using remove_silencers!.
You need to add one more thing to the end of spec/spec_helper.rb, which will reset
your database back to a clean slate once all of your tests have finished running. It will
do this by running the test’s database queries inside a transaction, which is then rolled
back at the end of the test. That would be this little configuration option:
RSpec.configure do |config|
config.use_transactional_fixtures = true
end
Without this, test data would accumulate in your database, leading to undesired
results.
Your next step in replacing Test::Unit with RSpec is to move the test/dummy directory
to spec/dummy. This folder is the dummy application for your engine and contains
the all-important config/environment.rb file, which is required in spec/
spec_helper.rb.
With all this code moved over, you can remove the test directory completely,
because you don’t need it any more. The test/dummy directory itself is still referenced
in the engine in a couple of places, and you’ll need to replace these references with
the new spec/dummy location.
The first of these locations is the Rakefile file at the root of the engine. This file is
loaded when any rake task is executed and is responsible for loading those tasks. You
need to replace this line in Rakefile
APP_RAKEFILE = File.expand_path("../test/dummy/Rakefile", __FILE__)
with this:
APP_RAKEFILE = File.expand_path("../spec/dummy/Rakefile", __FILE__)