How should I upgrade a Rails app to use the latest

Question

I'm working on a Rails app that currently uses Rails 1.2, so I'm now quite a long way behind the latest stable release (Rails 2.3).

How should I go about the process of moving to a newer version of Rails?

Should I upgrade one point release at a time or straight to Rails 2.3?

How do I find out what has changed between versions of Rails, both

• improvements or new features that give me more reasons to upgrade
• Rails changes that will require me to modify my app before it will work with the new version.

(I have seen this question on the mechanics of upgrading, but I'm more interested in the process I should go through to make the upgrade as painless as possible.)

Answer 1

You've probably had plenty of experience with this at this point, but I ran across this while searching for a different Rails 1.2>2.3 upgrade question, and thought I'd toss in a little advice myself:

The biggest break I had in a relatively simple app was with Pagination. I found the Classic Pagination plugin to be a godsend for this.