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class Time
Constants
- COMMON_YEAR_DAYS_IN_MONTH
- DATE_FORMATS
Attributes
Public Class Methods
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 15
def ===(other)
  super || (self == Time && other.is_a?(ActiveSupport::TimeWithZone))
endOverriding case equality method so that it returns true for ActiveSupport::TimeWithZone instances
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 42
def at_with_coercion(*args)
  return at_without_coercion(*args) if args.size != 1
  # Time.at can be called with a time or numerical value
  time_or_number = args.first
  if time_or_number.is_a?(ActiveSupport::TimeWithZone) || time_or_number.is_a?(DateTime)
    at_without_coercion(time_or_number.to_f).getlocal
  else
    at_without_coercion(time_or_number)
  end
endLayers additional behavior on ::at so that ActiveSupport::TimeWithZone and DateTime instances can be used when called with a single argument
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 36
def current
  ::Time.zone ? ::Time.zone.now : ::Time.now
endReturns Time.zone.now when Time.zone or config.time_zone are set, otherwise just returns Time.now.
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 21
def days_in_month(month, year = current.year)
  if month == 2 && ::Date.gregorian_leap?(year)
    29
  else
    COMMON_YEAR_DAYS_IN_MONTH[month]
  end
endReturns the number of days in the given month. If no year is specified, it will use the current year.
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 31
def days_in_year(year = current.year)
  days_in_month(2, year) + 337
endReturns the number of days in the given year. If no year is specified, it will use the current year.
# File activesupport/lib/active_support/core_ext/time/zones.rb, line 107
def find_zone(time_zone)
  find_zone!(time_zone) rescue nil
endReturns a TimeZone instance matching the time zone provided. Accepts the time zone in any format supported by Time.zone=. Returns nil for invalid time zones.
Time.find_zone "America/New_York" # => #<ActiveSupport::TimeZone @name="America/New_York" ...>
Time.find_zone "NOT-A-TIMEZONE"   # => nil
# File activesupport/lib/active_support/core_ext/time/zones.rb, line 80
def find_zone!(time_zone)
  if !time_zone || time_zone.is_a?(ActiveSupport::TimeZone)
    time_zone
  else
    # Look up the timezone based on the identifier (unless we've been
    # passed a TZInfo::Timezone)
    unless time_zone.respond_to?(:period_for_local)
      time_zone = ActiveSupport::TimeZone[time_zone] || TZInfo::Timezone.get(time_zone)
    end
    # Return if a TimeZone instance, or wrap in a TimeZone instance if a TZInfo::Timezone
    if time_zone.is_a?(ActiveSupport::TimeZone)
      time_zone
    else
      ActiveSupport::TimeZone.create(time_zone.name, nil, time_zone)
    end
  end
rescue TZInfo::InvalidTimezoneIdentifier
  raise ArgumentError, "Invalid Timezone: #{time_zone}"
endReturns a TimeZone instance matching the time zone provided. Accepts the time zone in any format supported by Time.zone=. Raises an ArgumentError for invalid time zones.
Time.find_zone! "America/New_York" # => #<ActiveSupport::TimeZone @name="America/New_York" ...>
Time.find_zone! "EST"              # => #<ActiveSupport::TimeZone @name="EST" ...>
Time.find_zone! -5.hours           # => #<ActiveSupport::TimeZone @name="Bogota" ...>
Time.find_zone! nil                # => nil
Time.find_zone! false              # => false
Time.find_zone! "NOT-A-TIMEZONE"   # => ArgumentError: Invalid Timezone: NOT-A-TIMEZONE
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 64
def rfc3339(str)
  parts = Date._rfc3339(str)
  raise ArgumentError, "invalid date" if parts.empty?
  Time.new(
    parts.fetch(:year),
    parts.fetch(:mon),
    parts.fetch(:mday),
    parts.fetch(:hour),
    parts.fetch(:min),
    parts.fetch(:sec) + parts.fetch(:sec_fraction, 0),
    parts.fetch(:offset)
  )
endCreates a Time instance from an RFC 3339 string.
Time.rfc3339('1999-12-31T14:00:00-10:00') # => 2000-01-01 00:00:00 -1000
If the time or offset components are missing then an ArgumentError will be raised.
Time.rfc3339('1999-12-31') # => ArgumentError: invalid date
# File activesupport/lib/active_support/core_ext/time/zones.rb, line 60
def use_zone(time_zone)
  new_zone = find_zone!(time_zone)
  begin
    old_zone, ::Time.zone = ::Time.zone, new_zone
    yield
  ensure
    ::Time.zone = old_zone
  end
endAllows override of Time.zone locally inside supplied block; resets Time.zone to existing value when done.
 class ApplicationController < ActionController::Base
   around_action :set_time_zone
   private
   def set_time_zone
     Time.use_zone(current_user.timezone) { yield }
   end
 end
NOTE: This won't affect any <tt>ActiveSupport::TimeWithZone</tt>
objects that have already been created, e.g. any model timestamp
attributes that have been read before the block will remain in
the application's default timezone.# File activesupport/lib/active_support/core_ext/time/zones.rb, line 12
def zone
  Thread.current[:time_zone] || zone_default
endReturns the TimeZone for the current request, if this has been set (via ::zone=). If Time.zone has not been set for the current request, returns the TimeZone specified in config.time_zone.
# File activesupport/lib/active_support/core_ext/time/zones.rb, line 39
def zone=(time_zone)
  Thread.current[:time_zone] = find_zone!(time_zone)
endSets Time.zone to a TimeZone object for the current request/thread.
This method accepts any of the following:
- A Rails TimeZone object. 
- An identifier for a Rails TimeZone object (e.g., “Eastern Time (US & Canada)”, - -5.hours).
- A TZInfo::Timezone object. 
- An identifier for a TZInfo::Timezone object (e.g., “America/New_York”). 
Here's an example of how you might set Time.zone on a per request basis and reset it when the request is done. current_user.time_zone just needs to return a string identifying the user's preferred time zone:
class ApplicationController < ActionController::Base
  around_action :set_time_zone
  def set_time_zone
    if logged_in?
      Time.use_zone(current_user.time_zone) { yield }
    else
      yield
    end
  end
end
Public Instance Methods
# File activesupport/lib/active_support/core_ext/time/acts_like.rb, line 5
def acts_like_time?
  true
endDuck-types as a Time-like class. See Object#acts_like?.
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 154
def advance(options)
  unless options[:weeks].nil?
    options[:weeks], partial_weeks = options[:weeks].divmod(1)
    options[:days] = options.fetch(:days, 0) + 7 * partial_weeks
  end
  unless options[:days].nil?
    options[:days], partial_days = options[:days].divmod(1)
    options[:hours] = options.fetch(:hours, 0) + 24 * partial_days
  end
  d = to_date.advance(options)
  d = d.gregorian if d.julian?
  time_advanced_by_date = change(year: d.year, month: d.month, day: d.day)
  seconds_to_advance =        options.fetch(:seconds, 0) +
    options.fetch(:minutes, 0) * 60 +
    options.fetch(:hours, 0) * 3600
  if seconds_to_advance.zero?
    time_advanced_by_date
  else
    time_advanced_by_date.since(seconds_to_advance)
  end
endUses Date to provide precise Time calculations for years, months, and days according to the proleptic Gregorian calendar. The options parameter takes a hash with any of these keys: :years, :months, :weeks, :days, :hours, :minutes, :seconds.
Time.new(2015, 8, 1, 14, 35, 0).advance(seconds: 1) # => 2015-08-01 14:35:01 -0700
Time.new(2015, 8, 1, 14, 35, 0).advance(minutes: 1) # => 2015-08-01 14:36:00 -0700
Time.new(2015, 8, 1, 14, 35, 0).advance(hours: 1)   # => 2015-08-01 15:35:00 -0700
Time.new(2015, 8, 1, 14, 35, 0).advance(days: 1)    # => 2015-08-02 14:35:00 -0700
Time.new(2015, 8, 1, 14, 35, 0).advance(weeks: 1)   # => 2015-08-08 14:35:00 -0700
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 194
def beginning_of_day
  change(hour: 0)
endReturns a new Time representing the start of the day (0:00)
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 223
def beginning_of_hour
  change(min: 0)
endReturns a new Time representing the start of the hour (x:00)
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 239
def beginning_of_minute
  change(sec: 0)
endReturns a new Time representing the start of the minute (x:xx:00)
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 118
def change(options)
  new_year  = options.fetch(:year, year)
  new_month = options.fetch(:month, month)
  new_day   = options.fetch(:day, day)
  new_hour  = options.fetch(:hour, hour)
  new_min   = options.fetch(:min, options[:hour] ? 0 : min)
  new_sec   = options.fetch(:sec, (options[:hour] || options[:min]) ? 0 : sec)
  if new_nsec = options[:nsec]
    raise ArgumentError, "Can't change both :nsec and :usec at the same time: #{options.inspect}" if options[:usec]
    new_usec = Rational(new_nsec, 1000)
  else
    new_usec = options.fetch(:usec, (options[:hour] || options[:min] || options[:sec]) ? 0 : Rational(nsec, 1000))
  end
  if utc?
    ::Time.utc(new_year, new_month, new_day, new_hour, new_min, new_sec, new_usec)
  elsif zone
    ::Time.local(new_year, new_month, new_day, new_hour, new_min, new_sec, new_usec)
  else
    raise ArgumentError, "argument out of range" if new_usec >= 1000000
    ::Time.new(new_year, new_month, new_day, new_hour, new_min, new_sec + (new_usec.to_r / 1000000), utc_offset)
  end
endReturns a new Time 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. Pass either :usec or :nsec, not both.
Time.new(2012, 8, 29, 22, 35, 0).change(day: 1)              # => Time.new(2012, 8, 1, 22, 35, 0)
Time.new(2012, 8, 29, 22, 35, 0).change(year: 1981, day: 1)  # => Time.new(1981, 8, 1, 22, 35, 0)
Time.new(2012, 8, 29, 22, 35, 0).change(year: 1981, hour: 0) # => Time.new(1981, 8, 29, 0, 0, 0)
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 285
def compare_with_coercion(other)
  # we're avoiding Time#to_datetime and Time#to_time because they're expensive
  if other.class == Time
    compare_without_coercion(other)
  elsif other.is_a?(Time)
    compare_without_coercion(other.to_time)
  else
    to_datetime <=> other
  end
endLayers additional behavior on Time#<=> so that DateTime and ActiveSupport::TimeWithZone instances can be chronologically compared with a Time
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 212
def end_of_day
  change(
    hour: 23,
    min: 59,
    sec: 59,
    usec: Rational(999999999, 1000)
  )
endReturns a new Time representing the end of the day, 23:59:59.999999
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 229
def end_of_hour
  change(
    min: 59,
    sec: 59,
    usec: Rational(999999999, 1000)
  )
endReturns a new Time representing the end of the hour, x:59:59.999999
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 245
def end_of_minute
  change(
    sec: 59,
    usec: Rational(999999999, 1000)
  )
endReturns a new Time representing the end of the minute, x:xx:59.999999
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 300
def eql_with_coercion(other)
  # if other is an ActiveSupport::TimeWithZone, coerce a Time instance from it so we can do eql? comparison
  other = other.comparable_time if other.respond_to?(:comparable_time)
  eql_without_coercion(other)
endLayers additional behavior on #eql? so that ActiveSupport::TimeWithZone instances can be eql? to an equivalent Time
# File activesupport/lib/active_support/core_ext/time/conversions.rb, line 64
def formatted_offset(colon = true, alternate_utc_string = nil)
  utc? && alternate_utc_string || ActiveSupport::TimeZone.seconds_to_utc_offset(utc_offset, colon)
endReturns a formatted string of the offset from UTC, or an alternative string if the time zone is already UTC.
Time.local(2000).formatted_offset        # => "-06:00"
Time.local(2000).formatted_offset(false) # => "-0600"
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 202
def middle_of_day
  change(hour: 12)
endReturns a new Time representing the middle of the day (12:00)
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 276
def minus_with_coercion(other)
  other = other.comparable_time if other.respond_to?(:comparable_time)
  other.is_a?(DateTime) ? to_f - other.to_f : minus_without_coercion(other)
endTime#- can also be used to determine the number of seconds between two Time instances. We're layering on additional behavior so that ActiveSupport::TimeWithZone instances are coerced into values that Time#- will recognize
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 102
def sec_fraction
  subsec
endReturns the fraction of a second as a Rational
Time.new(2012, 8, 29, 0, 0, 0.5).sec_fraction # => (1/2)
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 86
def seconds_since_midnight
  to_i - change(hour: 0).to_i + (usec / 1.0e+6)
endReturns the number of seconds since 00:00:00.
Time.new(2012, 8, 29,  0,  0,  0).seconds_since_midnight # => 0.0
Time.new(2012, 8, 29, 12, 34, 56).seconds_since_midnight # => 45296.0
Time.new(2012, 8, 29, 23, 59, 59).seconds_since_midnight # => 86399.0
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 95
def seconds_until_end_of_day
  end_of_day.to_i - to_i
endReturns the number of seconds until 23:59:59.
Time.new(2012, 8, 29,  0,  0,  0).seconds_until_end_of_day # => 86399
Time.new(2012, 8, 29, 12, 34, 56).seconds_until_end_of_day # => 41103
Time.new(2012, 8, 29, 23, 59, 59).seconds_until_end_of_day # => 0
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 186
def since(seconds)
  self + seconds
rescue
  to_datetime.since(seconds)
endReturns a new Time representing the time a number of seconds since the instance time
# File activesupport/lib/active_support/core_ext/time/conversions.rb, line 49
def to_formatted_s(format = :default)
  if formatter = DATE_FORMATS[format]
    formatter.respond_to?(:call) ? formatter.call(self).to_s : strftime(formatter)
  else
    to_default_s
  end
endConverts to a formatted string. See DATE_FORMATS for built-in formats.
This method is aliased to to_s.
time = Time.now                    # => 2007-01-18 06:10:17 -06:00
time.to_formatted_s(:time)         # => "06:10"
time.to_s(:time)                   # => "06:10"
time.to_formatted_s(:db)           # => "2007-01-18 06:10:17"
time.to_formatted_s(:number)       # => "20070118061017"
time.to_formatted_s(:short)        # => "18 Jan 06:10"
time.to_formatted_s(:long)         # => "January 18, 2007 06:10"
time.to_formatted_s(:long_ordinal) # => "January 18th, 2007 06:10"
time.to_formatted_s(:rfc822)       # => "Thu, 18 Jan 2007 06:10:17 -0600"
time.to_formatted_s(:iso8601)      # => "2007-01-18T06:10:17-06:00"
Adding your own time formats to to_formatted_s
      You can add your own formats to the Time::DATE_FORMATS hash. Use the format name as the hash key and either a strftime string or Proc instance that takes a time argument as the value.
# config/initializers/time_formats.rb
Time::DATE_FORMATS[:month_and_year] = '%B %Y'
Time::DATE_FORMATS[:short_ordinal]  = ->(time) { time.strftime("%B #{time.day.ordinalize}") }
# File activesupport/lib/active_support/core_ext/time/compatibility.rb, line 11
def to_time
  preserve_timezone ? self : getlocal
endEither return self or the time in the local system timezone depending on the setting of ActiveSupport.to_time_preserves_timezone.
© 2004–2018 David Heinemeier Hansson
Licensed under the MIT License.