A note for those who are using ActiveResource.

I ran into a bit of a problem the other day, not with using the HttpMock class itself. Mocks work pretty well in ActiveResouce. The problem came about when I tried to not use HttpMock. I almost tore my hair out but eventually a simple solution came. Thanks to Jason for the shoulder surfing effect.

First - The Problem
In my functional tests I have two controller tests. Test A is tested against the an actual resource. Test B uses ActiveResource’s HttpMock class to fake resources.

The problem is with Test A. If I run the test on its own, ie ruby /test/functional/a_test.rb the test will run fine. If I run it as part of rake test or rake test:functionals I get errors from test A complaining that no response is set up for any of the requests made in the test. (ActiveResource::InvalidRequestError: No response recorded for...)

So it would seem that it is trying to use HttpMock even though I have not required it in this test. Somehow it is staying in scope having been required in test b. I know that HttpMock overrides the http class in ActiveResource::Connection so perhaps that class is not being reloaded and the method is staying overridden. I couldn’t find a way of resetting the environment that worked.

The Fix that I wish I found 6 hours earlier…

In Test B the following line was present outside any class definitions to make ActiveResource mocks work:
require 'active_resource/http_mock'

Moving that line into the TestCase class seems to restrain the scope of HttpMock so that it doesn’t interfere with other tests.
I placed the line inside the test setup method and all was well eg:

class BControllerTest < Test::Unit::TestCase
  def setup
    require 'active_resource/http_mock'
    ##rest of your code below....
  end
  #
  #
  #
end

My tests ran happily ever after.