A great productivity comes from the small things. When making sure that the app works fine on the new version of Rails, I had to fix failures like this one many many times:
{% highlight ruby %} PostsControllerTest#test_whatever Expected response to be a <200: ok>, but was a <422: Unprocessable Entity>. Expected: 200 Actual: 422 {% endhighlight %}
The test was usually fairly easy and it looked like this:
{% highlight ruby %} class PostsControllerTest < ActionDispatch::Integration def test_whatever post :create, params: { post: { title: "title" } }, format: :json, as: :json assert_response :ok end end {% endhighlight %}
Every time I wanted to look inside, I had to insert a debugger (pry)
before the assert_response line and check what kind of errors are present the response body.
I thought: what can I do to make it easier? And I came up with this patch:
{% highlight ruby %} module BetterAssertResponse def assert_response(*args) super rescue Minitest::Assertion => e if response.body.size < 200 better_message = "#{e.message}\nResponse body: #{response.body}" raise Minitest::Assertion, better_message else raise end end end ActionDispatch::IntegrationTest.prepend(BetterAssertResponse) {% endhighlight %}
Can you guess how it works?
Before:
{% highlight ruby %} PostsControllerTest#test_whatever Expected response to be a <200: ok>, but was a <422: Unprocessable Entity>. Expected: 200 Actual: 422 {% endhighlight %}
After:
{% highlight ruby %} PostsControllerTest#test_whatever Expected response to be a <200: ok>, but was a <422: Unprocessable Entity>. Expected: 200 Actual: 422 Response body: {"errors":["Invalid settings object for section '1'"]} {% endhighlight %}
This trick saves me and other developers a few seconds every time we need to fix a failing test. Counting the number of failing tests we had after upgrading Rails (> 1000), this potentually saves hours of work.
Good news: I've submitted a patch to Rails to bring this upstream.
You can do the same trick with ActionController::TestCase in your app. Unfortunatelly, we can't bring it into Rails because ActionController testing has been deprecated.
