Running Rails tests multiple times for I18n testing

Is it possible to wrap every single test created for a Rails website to make them run multiple times, each time with a slight change to global config? Specifically I want to be able to do:

For all supported languages
  Set I18n language to <next language>
  Run all tests

Since my tests fail if, for example, there is no French translation of 'Hello', I can then use this to at least confirm that 'something' exists in the French variant (although I don't, of course, know it's not 'au revoir' :-) ).