How to calculate next, previous business day in Rails?

Question

How to calculate next and previous business days in Rails?

Answer 1

This is a method I use in my production scheduling script:

require 'date'
def shift_business_days(date, incr)
  date = Date.parse(date.to_s)
  incr.abs.times do
    date += (incr < 0 ? -1 : 1)
    while date.saturday? || date.sunday? do
      date += (incr < 0 ? -1 : 1)
    end
  end
  date
end

It takes a date and a positive or negative integer incr as arguments, and increments or decrements the date by incr days, skipping weekends. This has the added benefit of being able handle a Date/Time object or any date string that Date.parse can handle. For example:

# (today is 2019-03-08)
shift_business_days(Time.now, 2)
##=> #

shift_business_days('5/20', -10)
##=> #