Today I was confronted with testing my API in Cucumber (I should actually write a post on it). The scenario I was testing was involving deleting a resource that does not belong to this user. As the resource it is not found it raises a ActiveRecord::RecordNotFound error, what is actually ok. The API client should actually not see the error, but have a 404 returned. I’ve implemented a custom error handling using an error controller and use the routing middlewhere as the “exceptions_app”. More on this can be found here.

Back to my original problem. Everything was working fine. Testing the destroyment using curl was giving me a nice 404 and a “error- not found” JSON response. However Cucumber was raising the error and did not show the error page. I spent some time googling and found a work around. Trying to implement that workaround in env.rb I saw a comment in the env.rb

# By default, any exception happening in your Rails application will bubble up
# to Cucumber so that your scenario will fail. This is a different from how
# your application behaves in the production environment, where an error page will
# be rendered instead.
# Sometimes we want to override this default behaviour and allow Rails to rescue
# exceptions and display an error page (just like when the app is running in production).
# Typical scenarios where you want to do this is when you test your error pages.
# There are two ways to allow Rails to rescue exceptions:
# 1) Tag your scenario (or feature) with @allow-rescue
# 2) Set the value below to true. Beware that doing this globally is not
# recommended as it will mask a lot of errors for you!</blockquote>

So rendering error pages is built in in Cucumber (should have thought about that earlier). It’s as simple as tagging the scenario with @allow-rescue.