Rails has helpers for months_ago, years_ago etc. But not weeks_ago. This patch adds a weeks_ago method to active_support, as well as a prev_week short hand method. Usage is the same as months_ago or prev_month. So, Date.new(2005,5,24).weeks_ago(2) will return Date.new(2005,5,10) And Date.new(2005,5,17).prev_week will return Date.new(2005,5,10) This is my first patch to Rails so hopefully I've done