# Assert\_difference gives undefined method error in unit tests **URL:** \ **Category:** Rails\ **Created:** [August 7, 2006, 1:17am UTC](https://www.ruby-forum.com/t/assert-difference-gives-undefined-method-error-in-unit-tests/101638 "2006-08-07T01:17:40Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![indigoi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/i/b3f665/32.png) [@indigoi](https://www.ruby-forum.com/u/indigoi)\ **Post date:** [August 7, 2006, 1:17am UTC](https://www.ruby-forum.com/t/assert-difference-gives-undefined-method-error-in-unit-tests/101638/1 "2006-08-07T01:17:40Z")
Hi there Am hitting undefined method errors for ‘assert\_difference’ in my unit tests under Rails 1.1.4 What could I be missing? Richard S. ---
**Author:** ![indigoi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/i/b3f665/32.png) [@indigoi](https://www.ruby-forum.com/u/indigoi)\ **Post date:** [August 7, 2006, 5:56am UTC](https://www.ruby-forum.com/t/assert-difference-gives-undefined-method-error-in-unit-tests/101638/2 "2006-08-07T05:56:52Z")
On 8/6/06, Richard S. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > removed\_email\_address@domain.invalid > [http://lists.rubyonrails.org/mailman/listinfo/rails](http://lists.rubyonrails.org/mailman/listinfo/rails) Just what it sounds like… that’s a custom assertion 🙂 ---
**Author:** ![indigoi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/i/b3f665/32.png) [@indigoi](https://www.ruby-forum.com/u/indigoi)\ **Post date:** [August 7, 2006, 9:30am UTC](https://www.ruby-forum.com/t/assert-difference-gives-undefined-method-error-in-unit-tests/101638/3 "2006-08-07T09:30:04Z")
Yeah, I got it going - I was using an old version of the plugin without the assert\_difference in authenticated\_test\_helper.rb But now I’m stuck on the ‘remember me’ functionality of the plugin, but that’s a seperate question for the list 🙂 Richard