Adding development gem dependencies to a rails application.

It has been possible to specify gem dependencies for your application for a while. But sometimes when moving to another machine we would complain about there not being a development dependency option for config.gem as there is for gems. But we hadn’t actually given it any thought…

Today I had some weird test failures, which were related to not having test-spec 0.9 installed on my macbook. Most tests did pass because I did have an older version installed. So after a few minutes of thinking about it, I finally figured out the stupid simple solution. Simply define the dependencies in config/environments/test.rb!

# Development gems:
config.gem 'test-spec', :version => '0.9', :lib => 'test/spec'
config.gem 'mocha', :version => '0.9.3'

This one is probably obvious to some, but as far as I know it has never been actively promoted. And it’s just too easy to think of ;-)