Rails 2.3.2 and testing with assert_select_email

I upgraded a project to Rails 2.3.2 a while back and have been getting the following error when running some unit tests…

NoMethodError: undefined method `assert_select_email' for #<UserMailerTest>

I posted to the rubyonrails-talk google group but never got a response, and I was not the first to post about this problem to that group. However I found someone else commenting on this in an rspec lighthouse ticket and they’d fixed it for their setup. It was an easy conversion to non-rspec and here’s the line you need to add to your test/test_helper.rb file

include ActionController::Assertions::SelectorAssertions

I’m not sure why it’s broken but it appears to have regressed in one of the Rails 2.3.2 RCs.