How to add Jasmine unit tests to a custom ruby gem?

We have a custom ruby gem that we use within some of our rails apps. This gem contains some Javascript libraries which I would like to test with Jasmine. I see plenty of examples of how to include Jasmine in my rails app, and we do use it for testing there. But I haven;t found any examples of how to use it within a custom gem. Any insight would be greatly appreciated.