2.months.ago

Ruby on Rails has many useful helpers and extensions to core Ruby. Everyone using Rails does know forms like 10.days.ago or 2.months.ago. Well the former is sometimes risky one. Why? Look at this:

./script/console
Loading development environment.
>> Time.now
=> Mon Mar 12 13:58:16 +0100 2007
>> 12.months.ago
=> Fri Mar 17 13:58:19 +0100 2006
>>

This is what You have expected? Well in that case You probably know that months has this simple definition:

44:         def months
45:           self * 30.days
46:         end

Time travel was anticipated as an hard task :) and it is really. So what is answer to question: how to travel back in time with right months calculations? It is Time#advance:

>> Time.now
=> Mon Mar 12 14:02:42 +0100 2007
>> Time.now.advance(:months => -2)
=> Fri Jan 12 14:02:43 +0100 2007
>>

Got it?