thoughtbot/factory_girl — comment on commit f2e41389ea3f8fd455d7a14a0241c6a1ce8d801a
File: lib/factory_girl/evaluator.rb line 1
By ngan:

Rails 2.3 does not have this...

I'm getting the following error:
```
activesupport-2.3.2/lib/active_support/dependencies.rb:158:in `require': no such file to load -- active_support/core_ext/class/attribute (MissingSourceFile)
```