Functional test parameters should be strings

HTTP parameters aren't integers or Date objects or ActiveRecords, but
Rails functional tests allow you to pass all of these things as
parameters to test requests. Tests should emulate real life, so I
wrote up a patch that verifies that all parameters you send in a
request for a functional test are properly typed.

I'm sure this will break plenty of tests (I had to fix quite a few
Rails tests), but it will make your tests better, and that should save
time in the long run. I'm curious to hear about any edge cases I
didn't think of.

Check it out here:
https://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/2970-parameters-to-functional-test-requests-should-have-proper-values