undefined method `camelize' for "default_search_form":String (NoMethodError)

I encountered that camelize error a few weeks ago. It was quite frustrating since I have not modified my code and the error was quite unfamiliar for me. After doing a bit more research and trial and error I found out the error is caused by activesupport 3.0.

undefined method `camelize' for "default_search_form":String (NoMethodError)

I used a ruby gem called Gizmo which is a simple page model testing framework. At that time, I was using Gizmo version 0.1.0 which was using activesupport 3.0. Apparently, activesupport 3.0 is not compatible with Gizmo or some other gems that I am using in my code.

To fix the issue I simply downgraded my activesupport gem to be 2.3.3. However, Gizmo gem has now been updated to 0.1.1 which uses the correct version of activesupport.