Testing time in Rails with Minitest

Time travel

Some tests are time-sensitive. Luckily for us, Rails has nice time helpers like freeze_time, travel_to, travel_back, and travel:

Time.current     # => Sat, 09 Nov 2013 15:34:49 EST -05:00
travel_to Time.zone.local(2004, 11, 24, 01, 04, 44)
Time.current     # => Wed, 24 Nov 2004 01:04:44 EST -05:00
Date.current     # => Wed, 24 Nov 2004
DateTime.current # => Wed, 24 Nov 2004 01:04:44 -0500

They also come in a block variant isolating the action we need:

# Travel forward in time
Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00
travel 1.day do
  User.create.created_at # => Sun, 10 Nov 2013 15:34:49 EST -05:00
end
Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00

This way we can control time in our tests and make sure everything works as expected.