Inside this directory you'll find a Ruby program to format date ranges with optional start and end times.
You can run its test suite like so:
$ bundle install
$ rspec
The main code can be found in lib/date_range_formatter.rb and its behaviour is defined in spec/date_range_formatter_spec.rb
However, the code is difficult to read and seems to have a bug: when given a start date of 2009-11-1 and an end date of 2010-11-3, it should format the date range as "1st November 2009 - 3rd November 2010" but actually returns "1st - 3rd November 2009".
Find and fix the bug, writing tests if need be and refactor the code as you see fit.