Let's push this down a level, make it more of a unit test than an integration test.  Instantiate a Printable like https://github.com/arches/table_print/blob/master/lib/table_print.rb#L45 and assert the resultant display methods.  On that note, let's also move this into printable_spec.

An integration test wouldn't be unreasonable, but it should go in a feature rather than a spec.