Method: ActiveSupport::TimeWithZone#change

Defined in:
activesupport/lib/active_support/time_with_zone.rb

#change(options) ⇒ Object

Returns a new ActiveSupport::TimeWithZone where one or more of the elements have been changed according to the options parameter. The time options (:hour, :min, :sec, :usec, :nsec) reset cascadingly, so if only the hour is passed, then minute, sec, usec, and nsec is set to 0. If the hour and minute is passed, then sec, usec, and nsec is set to 0. The options parameter takes a hash with any of these keys: :year, :month, :day, :hour, :min, :sec, :usec, :nsec, :offset, :zone. Pass either :usec or :nsec, not both. Similarly, pass either :zone or :offset, not both.

t = Time.zone.now          # => Fri, 14 Apr 2017 11:45:15.116992711 EST -05:00
t.change(year: 2020)       # => Tue, 14 Apr 2020 11:45:15.116992711 EST -05:00
t.change(hour: 12)         # => Fri, 14 Apr 2017 12:00:00.000000000 EST -05:00
t.change(min: 30)          # => Fri, 14 Apr 2017 11:30:00.000000000 EST -05:00
t.change(offset: "-10:00") # => Fri, 14 Apr 2017 11:45:15.116992711 HST -10:00
t.change(zone: "Hawaii")   # => Fri, 14 Apr 2017 11:45:15.116992711 HST -10:00


382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
# File 'activesupport/lib/active_support/time_with_zone.rb', line 382

def change(options)
  if options[:zone] && options[:offset]
    raise ArgumentError, "Can't change both :offset and :zone at the same time: #{options.inspect}"
  end

  new_time = time.change(options)

  if options[:zone]
    new_zone = ::Time.find_zone(options[:zone])
  elsif options[:offset]
    new_zone = ::Time.find_zone(new_time.utc_offset)
  end

  new_zone ||= time_zone
  periods = new_zone.periods_for_local(new_time)

  self.class.new(nil, new_zone, new_time, periods.include?(period) ? period : nil)
end