Sadly Rubymine still hasn’t resolved the debugger issue when trying to debug a Ruby 1.9.x application inside Rubymine. It’s not hard to get the debugger up and running when you know how, there’s also a lot of chatter among the topic.
It boils down to the following steps:
1) Download linecache19 0.5.13 and install it with
gem install linecache19-0.5.13.gem
2) Install the 1.9.x Ruby debug base (pre-release)
gem install ruby-debug-base19x --pre
3) Install the 1.9.x Ruby debug ide (also pre-release)
gem install ruby-debug-ide19 --pre
4) Start Rubymine and you’re set!