class Time

Constants

COMMON_YEAR_DAYS_IN_MONTH
DATE_FORMATS

Attributes

Public Class Methods

Overriding case equality method so that it returns true for ActiveSupport::TimeWithZone instances

Calls superclass method
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 18
def ===(other)
  super || (self == Time && other.is_a?(ActiveSupport::TimeWithZone))
end

Layers additional behavior on Time.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 45
def at_with_coercion(*args, **kwargs)
  return at_without_coercion(*args, **kwargs) if args.size != 1 || !kwargs.empty?

  # Time.at can be called with a time or numerical value
  time_or_number = args.first

  if time_or_number.is_a?(ActiveSupport::TimeWithZone)
    at_without_coercion(time_or_number.to_r).getlocal
  elsif time_or_number.is_a?(DateTime)
    at_without_coercion(time_or_number.to_f).getlocal
  else
    at_without_coercion(time_or_number)
  end
end
Also aliased as: at

Returns 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 39
def current
  ::Time.zone ? ::Time.zone.now : ::Time.now
end

Returns 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 24
def days_in_month(month, year = current.year)
  if month == 2 && ::Date.gregorian_leap?(year)
    29
  else
    COMMON_YEAR_DAYS_IN_MONTH[month]
  end
end

Returns 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/calculations.rb, line 34
def days_in_year(year = current.year)
  days_in_month(2, year) + 337
end

Returns 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 93
def find_zone(time_zone)
  find_zone!(time_zone) rescue nil
end

Returns 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/zones.rb, line 81
def find_zone!(time_zone)
  return time_zone unless time_zone

  ActiveSupport::TimeZone[time_zone] || raise(ArgumentError, "Invalid Timezone: #{time_zone}")
end

Creates 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/calculations.rb, line 69
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)
  )
end

Allows 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 ActiveSupport::TimeWithZone 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 61
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
end

Returns the TimeZone for the current request, if this has been set (via Time.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 14
def zone
  ::ActiveSupport::IsolatedExecutionState[:time_zone] || zone_default
end

Sets 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
# File activesupport/lib/active_support/core_ext/time/zones.rb, line 41
def zone=(time_zone)
  ::ActiveSupport::IsolatedExecutionState[:time_zone] = find_zone!(time_zone)
end

Public Instance Methods

Duck-types as a Time-like class. See Object#acts_like?.

# File activesupport/lib/active_support/core_ext/time/acts_like.rb, line 7
def acts_like_time?
  true
end

Uses 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

Just like Date#advance, increments are applied in order of time units from largest to smallest. This order can affect the result around the end of a month.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 202
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.gregorian.advance(options)
  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
end

Returns a new Time representing the time a number of seconds ago, this is basically a wrapper around the Numeric extension

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 228
def ago(seconds)
  since(-seconds)
end

Returns a new Time representing the start of the day (0:00)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 241
def beginning_of_day
  change(hour: 0)
end

Returns a new Time representing the start of the hour (x:00)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 270
def beginning_of_hour
  change(min: 0)
end
Also aliased as: at_beginning_of_hour

Returns a new Time representing the start of the minute (x:xx:00)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 286
def beginning_of_minute
  change(sec: 0)
end
Also aliased as: at_beginning_of_minute
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 121
def ceil(precision = 0)
  change(nsec: 0) + subsec.ceil(precision)
end

Returns 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, :offset. 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 138
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)
  new_offset = options.fetch(:offset, nil)

  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

  raise ArgumentError, "argument out of range" if new_usec >= 1000000

  new_sec += Rational(new_usec, 1000000)

  if new_offset
    ::Time.new(new_year, new_month, new_day, new_hour, new_min, new_sec, new_offset)
  elsif utc?
    ::Time.utc(new_year, new_month, new_day, new_hour, new_min, new_sec)
  elsif zone&.respond_to?(:utc_to_local)
    new_time = ::Time.new(new_year, new_month, new_day, new_hour, new_min, new_sec, zone)

    # When there are two occurrences of a nominal time due to DST ending,
    # `Time.new` chooses the first chronological occurrence (the one with a
    # larger UTC offset). However, for `change`, we want to choose the
    # occurrence that matches this time's UTC offset.
    #
    # If the new time's UTC offset is larger than this time's UTC offset, the
    # new time might be a first chronological occurrence. So we add the offset
    # difference to fast-forward the new time, and check if the result has the
    # desired UTC offset (i.e. is the second chronological occurrence).
    offset_difference = new_time.utc_offset - utc_offset
    if offset_difference > 0 && (new_time_2 = new_time + offset_difference).utc_offset == utc_offset
      new_time_2
    else
      new_time
    end
  elsif zone
    ::Time.local(new_sec, new_min, new_hour, new_day, new_month, new_year, nil, nil, isdst, nil)
  else
    ::Time.new(new_year, new_month, new_day, new_hour, new_min, new_sec, utc_offset)
  end
end

Layers 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 332
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
end
Also aliased as: <=>

Returns a new Time representing the end of the day, 23:59:59.999999

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 259
def end_of_day
  change(
    hour: 23,
    min: 59,
    sec: 59,
    usec: Rational(999999999, 1000)
  )
end
Also aliased as: at_end_of_day

Returns a new Time representing the end of the hour, x:59:59.999999

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 276
def end_of_hour
  change(
    min: 59,
    sec: 59,
    usec: Rational(999999999, 1000)
  )
end
Also aliased as: at_end_of_hour

Returns a new Time representing the end of the minute, x:xx:59.999999

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 292
def end_of_minute
  change(
    sec: 59,
    usec: Rational(999999999, 1000)
  )
end
Also aliased as: at_end_of_minute

Layers additional behavior on Time#eql? so that ActiveSupport::TimeWithZone instances can be eql? to an equivalent Time

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 347
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)
end
Also aliased as: eql?
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 112
def floor(precision = 0)
  change(nsec: 0) + subsec.floor(precision)
end

Returns 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/conversions.rb, line 69
def formatted_offset(colon = true, alternate_utc_string = nil)
  utc? && alternate_utc_string || ActiveSupport::TimeZone.seconds_to_utc_offset(utc_offset, colon)
end

Returns a new Time representing the middle of the day (12:00)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 249
def middle_of_day
  change(hour: 12)
end

Time#- 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 323
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)
end
Also aliased as: -

Returns a new time the specified number of days in the future.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 361
def next_day(days = 1)
  advance(days: days)
end

Returns a new time the specified number of months in the future.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 371
def next_month(months = 1)
  advance(months: months)
end

Returns a new time the specified number of years in the future.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 381
def next_year(years = 1)
  advance(years: years)
end

Returns a new time the specified number of days ago.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 356
def prev_day(days = 1)
  advance(days: -days)
end

Returns a new time the specified number of months ago.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 366
def prev_month(months = 1)
  advance(months: -months)
end

Returns a new time the specified number of years ago.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 376
def prev_year(years = 1)
  advance(years: -years)
end

Returns 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 107
def sec_fraction
  subsec
end

Returns 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 91
def seconds_since_midnight
  to_i - change(hour: 0).to_i + (usec / 1.0e+6)
end

Returns 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 100
def seconds_until_end_of_day
  end_of_day.to_i - to_i
end

Returns a new Time representing the time a number of seconds since the instance time

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 233
def since(seconds)
  self + seconds
rescue
  to_datetime.since(seconds)
end
Also aliased as: in

Converts to a formatted string. See DATE_FORMATS for built-in formats.

This method is aliased to to_formatted_s.

time = Time.now                    # => 2007-01-18 06:10:17 -06:00

time.to_fs(:time)                  # => "06:10"
time.to_formatted_s(:time)         # => "06:10"

time.to_fs(:db)           # => "2007-01-18 06:10:17"
time.to_fs(:number)       # => "20070118061017"
time.to_fs(:short)        # => "18 Jan 06:10"
time.to_fs(:long)         # => "January 18, 2007 06:10"
time.to_fs(:long_ordinal) # => "January 18th, 2007 06:10"
time.to_fs(:rfc822)       # => "Thu, 18 Jan 2007 06:10:17 -0600"
time.to_fs(:iso8601)      # => "2007-01-18T06:10:17-06:00"

Adding your own time formats to to_fs

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/conversions.rb, line 53
def to_fs(format = :default)
  if formatter = DATE_FORMATS[format]
    formatter.respond_to?(:call) ? formatter.call(self).to_s : strftime(formatter)
  else
    to_s
  end
end
Also aliased as: to_formatted_s

Either return self or the time in the local system timezone depending on the setting of ActiveSupport.to_time_preserves_timezone.

# File activesupport/lib/active_support/core_ext/time/compatibility.rb, line 13
def to_time
  preserve_timezone ? self : getlocal
end