# class Date

### Constants

DATE_FORMATS
DAYS_INTO_WEEK

### Public Class Methods

current() click to toggle source

Returns Time.zone.today when `Time.zone` or `config.time_zone` are set, otherwise just returns Date.today.

    # File lib/active_support/core_ext/date/calculations.rb, line 40
    def current
      ::Time.zone ? ::Time.zone.today : ::Date.today
    end

tomorrow() click to toggle source

Returns a new Date representing the date 1 day after today (i.e. tomorrow’s date).

    # File lib/active_support/core_ext/date/calculations.rb, line 35
    def tomorrow
      ::Date.current.tomorrow
    end

yesterday() click to toggle source

Returns a new Date representing the date 1 day ago (i.e. yesterday’s date).

    # File lib/active_support/core_ext/date/calculations.rb, line 30
    def yesterday
      ::Date.current.yesterday
    end

### Public Instance Methods

>>(n) click to toggle source

Backported from 1.9. The one in 1.8 leads to incorrect #next_month and friends for dates where the calendar reform is involved. It additionally prevents an infinite loop fixed in r27013.

    # File lib/active_support/core_ext/date/calculations.rb, line 16
    def >>(n)
      y, m = (year * 12 + (mon - 1) + n).divmod(12)
      m,   = (m + 1)                    .divmod(1)
      d = mday
      until jd2 = self.class.valid_civil?(y, m, d, start)
        d -= 1
        raise ArgumentError, 'invalid date' unless d > 0
      end
      self + (jd2 - jd)
    end

acts_like_date?() click to toggle source

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

    # File lib/active_support/core_ext/date/acts_like.rb, line 5
    def acts_like_date?
      true
    end

advance(options) click to toggle source

Provides precise Date calculations for years, months, and days. The `options` parameter takes a hash with any of these keys: `:years`, `:months`, `:weeks`, `:days`.

    # File lib/active_support/core_ext/date/calculations.rb, line 108
    def advance(options)
      options = options.dup
      d = self
      d = d >> options.delete(:years) * 12 if options[:years]
      d = d >> options.delete(:months)     if options[:months]
      d = d +  options.delete(:weeks) * 7  if options[:weeks]
      d = d +  options.delete(:days)       if options[:days]
      d
    end

ago(seconds) click to toggle source

Converts Date to a Time (or DateTime if necessary) with the time portion set to the beginning of the day (0:00) and then subtracts the specified number of seconds.

    # File lib/active_support/core_ext/date/calculations.rb, line 62
    def ago(seconds)
      to_time_in_current_zone.since(-seconds)
    end

at_beginning_of_day() click to toggle source
Alias for: beginning_of_day
at_beginning_of_month() click to toggle source
Alias for: beginning_of_month
at_beginning_of_quarter() click to toggle source
Alias for: beginning_of_quarter
at_beginning_of_week(start_day = :monday) click to toggle source
Alias for: beginning_of_week
at_beginning_of_year() click to toggle source
Alias for: beginning_of_year
at_end_of_month() click to toggle source
Alias for: end_of_month
at_end_of_quarter() click to toggle source
Alias for: end_of_quarter
at_end_of_week(start_day = :monday) click to toggle source
Alias for: end_of_week
at_end_of_year() click to toggle source
Alias for: end_of_year
at_midnight() click to toggle source
Alias for: beginning_of_day
beginning_of_day() click to toggle source

Converts Date to a Time (or DateTime if necessary) with the time portion set to the beginning of the day (0:00)

    # File lib/active_support/core_ext/date/calculations.rb, line 74
    def beginning_of_day
      to_time_in_current_zone
    end

Also aliased as: midnight, at_midnight, at_beginning_of_day
beginning_of_month() click to toggle source

Returns a new ; DateTime objects will have time set to 0:00DateTime representing the start of the month (1st of the month; DateTime objects will have time set to 0:00)

    # File lib/active_support/core_ext/date/calculations.rb, line 231
    def beginning_of_month
      self.acts_like?(:time) ? change(:day => 1, :hour => 0) : change(:day => 1)
    end

Also aliased as: at_beginning_of_month
beginning_of_quarter() click to toggle source

Returns a new Date/DateTime representing the start of the quarter (1st of january, april, july, october; DateTime objects will have time set to 0:00)

    # File lib/active_support/core_ext/date/calculations.rb, line 244
    def beginning_of_quarter
      beginning_of_month.change(:month => [10, 7, 4, 1].detect { |m| m <= self.month })
    end

Also aliased as: at_beginning_of_quarter
beginning_of_week(start_day = :monday) click to toggle source

Returns a new `Date`/`DateTime` representing the start of this week. Week is assumed to start on `start_day`, default is `:monday`. `DateTime` objects have their time set to 0:00.

    # File lib/active_support/core_ext/date/calculations.rb, line 188
    def beginning_of_week(start_day = :monday)
      days_to_start = days_to_week_start(start_day)
      result = self - days_to_start
      acts_like?(:time) ? result.midnight : result
    end

Also aliased as: at_beginning_of_week
beginning_of_year() click to toggle source

Returns a new Date/DateTime representing the start of the year (1st of january; DateTime objects will have time set to 0:00)

    # File lib/active_support/core_ext/date/calculations.rb, line 256
    def beginning_of_year
      self.acts_like?(:time) ? change(:month => 1, :day => 1, :hour => 0) : change(:month => 1, :day => 1)
    end

Also aliased as: at_beginning_of_year
change(options) click to toggle source

Returns a new Date where one or more of the elements have been changed according to the `options` parameter.

Examples:

    Date.new(2007, 5, 12).change(:day => 1)                  # => Date.new(2007, 5, 1)
    Date.new(2007, 5, 12).change(:year => 2005, :month => 1) # => Date.new(2005, 1, 12)

    # File lib/active_support/core_ext/date/calculations.rb, line 124
    def change(options)
      ::Date.new(
        options[:year]  || self.year,
        options[:month] || self.month,
        options[:day]   || self.day
      )
    end

days_to_week_start(start_day = :monday) click to toggle source

Returns number of days to start of this week. Week is assumed to start on `start_day`, default is `:monday`.

    # File lib/active_support/core_ext/date/calculations.rb, line 179
    def days_to_week_start(start_day = :monday)
      start_day_number = DAYS_INTO_WEEK[start_day]
      current_day_number = wday != 0 ? wday - 1 : 6
      (current_day_number - start_day_number) % 7
    end

default_inspect() click to toggle source
Alias for: inspect
end_of_day() click to toggle source

Converts Date to a Time (or DateTime if necessary) with the time portion set to the end of the day (23:59:59)

    # File lib/active_support/core_ext/date/calculations.rb, line 82
    def end_of_day
      to_time_in_current_zone.end_of_day
    end

end_of_month() click to toggle source

Returns a new Date/DateTime representing the end of the month (last day of the month; DateTime objects will have time set to 0:00)

    # File lib/active_support/core_ext/date/calculations.rb, line 237
    def end_of_month
      last_day = ::Time.days_in_month( self.month, self.year )
      self.acts_like?(:time) ? change(:day => last_day, :hour => 23, :min => 59, :sec => 59) : change(:day => last_day)
    end

Also aliased as: at_end_of_month
end_of_quarter() click to toggle source

Returns a new Date/DateTime representing the end of the quarter (last day of march, june, september, december; DateTime objects will have time set to 23:59:59)

    # File lib/active_support/core_ext/date/calculations.rb, line 250
    def end_of_quarter
      beginning_of_month.change(:month => [3, 6, 9, 12].detect { |m| m >= self.month }).end_of_month
    end

Also aliased as: at_end_of_quarter
end_of_week(start_day = :monday) click to toggle source

Returns a new `Date`/`DateTime` representing the end of this week. Week is assumed to start on `start_day`, default is `:monday`. `DateTime` objects have their time set to 23:59:59.

    # File lib/active_support/core_ext/date/calculations.rb, line 204
    def end_of_week(start_day = :monday)
      days_to_end = 6 - days_to_week_start(start_day)
      result = self + days_to_end.days
      self.acts_like?(:time) ? result.end_of_day : result
    end

Also aliased as: at_end_of_week
end_of_year() click to toggle source

Returns a new Time representing the end of the year (31st of december; DateTime objects will have time set to 23:59:59)

    # File lib/active_support/core_ext/date/calculations.rb, line 262
    def end_of_year
      self.acts_like?(:time) ? change(:month => 12, :day => 31, :hour => 23, :min => 59, :sec => 59) : change(:month => 12, :day => 31)
    end

Also aliased as: at_end_of_year
future?() click to toggle source

Returns true if the Date object’s date lies in the future.

    # File lib/active_support/core_ext/date/calculations.rb, line 56
    def future?
      self > ::Date.current
    end

in(seconds) click to toggle source
Alias for: since
inspect() click to toggle source
Also aliased as: default_inspect
Alias for: readable_inspect
iso8601() click to toggle source

    # File lib/active_support/core_ext/date/conversions.rb, line 97
    def iso8601
      strftime('%F')
    end

Also aliased as: rfc3339
midnight() click to toggle source
Alias for: beginning_of_day
monday() click to toggle source

Returns a new `Date`/`DateTime` representing the start of this week. Week is assumed to start on a Monday. `DateTime` objects have their time set to 0:00.

    # File lib/active_support/core_ext/date/calculations.rb, line 197
    def monday
      beginning_of_week
    end

months_ago(months) click to toggle source

Returns a new Date/DateTime representing the time a number of specified months ago.

    # File lib/active_support/core_ext/date/calculations.rb, line 138
    def months_ago(months)
      advance(:months => -months)
    end

months_since(months) click to toggle source

Returns a new Date/DateTime representing the time a number of specified months in the future.

    # File lib/active_support/core_ext/date/calculations.rb, line 143
    def months_since(months)
      advance(:months => months)
    end

next_month() click to toggle source

Shorthand for #months_since(1)

    # File lib/active_support/core_ext/date/calculations.rb, line 173
    def next_month
      months_since(1)
    end

next_week(day = :monday) click to toggle source

Returns a new Date/DateTime representing the start of the given day in next week (default is :monday).

    # File lib/active_support/core_ext/date/calculations.rb, line 225
    def next_week(day = :monday)
      result = (self + 7).beginning_of_week + DAYS_INTO_WEEK[day]
      self.acts_like?(:time) ? result.change(:hour => 0) : result
    end

next_year() click to toggle source

Shorthand for #years_since(1)

    # File lib/active_support/core_ext/date/calculations.rb, line 163
    def next_year
      years_since(1)
    end

past?() click to toggle source

Returns true if the Date object’s date lies in the past. Otherwise returns false.

    # File lib/active_support/core_ext/date/calculations.rb, line 46
    def past?
      self < ::Date.current
    end

prev_month() click to toggle source

Shorthand for #months_ago(1)

    # File lib/active_support/core_ext/date/calculations.rb, line 168
    def prev_month
      months_ago(1)
    end

prev_week(day = :monday) click to toggle source

Returns a new `Date`/`DateTime` representing the given `day` in the previous week. Default is `:monday`. `DateTime` objects have their time set to 0:00.

    # File lib/active_support/core_ext/date/calculations.rb, line 219
    def prev_week(day = :monday)
      result = (self - 7).beginning_of_week + DAYS_INTO_WEEK[day]
      self.acts_like?(:time) ? result.change(:hour => 0) : result
    end

prev_year() click to toggle source

Shorthand for #years_ago(1)

    # File lib/active_support/core_ext/date/calculations.rb, line 158
    def prev_year
      years_ago(1)
    end

readable_inspect() click to toggle source

Overrides the default inspect method with a human readable one, e.g., “Mon, 21 Feb 2005”

    # File lib/active_support/core_ext/date/conversions.rb, line 60
    def readable_inspect
      strftime("%a, %d %b %Y")
    end

Also aliased as: inspect
rfc3339() click to toggle source
Alias for: iso8601
since(seconds) click to toggle source

Converts Date to a Time (or DateTime if necessary) with the time portion set to the beginning of the day (0:00) and then adds the specified number of seconds

    # File lib/active_support/core_ext/date/calculations.rb, line 68
    def since(seconds)
      to_time_in_current_zone.since(seconds)
    end

Also aliased as: in
sunday() click to toggle source

Returns a new `Date`/`DateTime` representing the end of this week. Week is assumed to start on a Monday. `DateTime` objects have their time set to 23:59:59.

    # File lib/active_support/core_ext/date/calculations.rb, line 213
    def sunday
      end_of_week
    end

to_date() click to toggle source

A method to keep Time, Date and DateTime instances interchangeable on conversions. In this case, it simply returns `self`.

    # File lib/active_support/core_ext/date/conversions.rb, line 68
    def to_date
      self
    end

to_datetime() click to toggle source

Converts a Date instance to a DateTime, where the time is set to the beginning of the day and UTC offset is set to 0.

#### Examples

    date = Date.new(2007, 11, 10)  # => Sat, 10 Nov 2007

    date.to_datetime               # => Sat, 10 Nov 2007 00:00:00 0000

    # File lib/active_support/core_ext/date/conversions.rb, line 93
    def to_datetime
      ::DateTime.civil(year, month, day, 0, 0, 0, 0)
    end

to_default_s(format = :default) click to toggle source
Alias for: to_s
to_formatted_s(format = :default) click to toggle source

Convert to a formatted string. See DATE_FORMATS for predefined formats.

This method is aliased to `to_s`.

#### Examples

    date = Date.new(2007, 11, 10)       # => Sat, 10 Nov 2007

    date.to_formatted_s(:db)            # => "2007-11-10"
    date.to_s(:db)                      # => "2007-11-10"

    date.to_formatted_s(:short)         # => "10 Nov"
    date.to_formatted_s(:long)          # => "November 10, 2007"
    date.to_formatted_s(:long_ordinal)  # => "November 10th, 2007"
    date.to_formatted_s(:rfc822)        # => "10 Nov 2007"

## Adding your own time formats to #to_formatted_s

You can add your own formats to the Date::DATE_FORMATS hash. Use the format name as the hash key and either a strftime string or Proc instance that takes a date argument as the value.

    # config/initializers/time_formats.rb
    Date::DATE_FORMATS[:month_and_year] = "%B %Y"
    Date::DATE_FORMATS[:short_ordinal] = lambda { |date| date.strftime("%B #{date.day.ordinalize}") }

    # File lib/active_support/core_ext/date/conversions.rb, line 45
    def to_formatted_s(format = :default)
      if formatter = DATE_FORMATS[format]
        if formatter.respond_to?(:call)
          formatter.call(self).to_s
        else
          strftime(formatter)
        end
      else
        to_default_s
      end
    end

Also aliased as: to_s
to_s(format = :default) click to toggle source
Also aliased as: to_default_s
Alias for: to_formatted_s
to_time(form = :local) click to toggle source

Converts a Date instance to a Time, where the time is set to the beginning of the day. The timezone can be either :local or :utc (default :local).

#### Examples

    date = Date.new(2007, 11, 10)  # => Sat, 10 Nov 2007

    date.to_time                   # => Sat Nov 10 00:00:00 0800 2007
    date.to_time(:local)           # => Sat Nov 10 00:00:00 0800 2007

    date.to_time(:utc)             # => Sat Nov 10 00:00:00 UTC 2007

    # File lib/active_support/core_ext/date/conversions.rb, line 82
    def to_time(form = :local)
      ::Time.send("#{form}_time", year, month, day)
    end

to_time_in_current_zone() click to toggle source

Converts Date to a TimeWithZone in the current zone if Time.zone or Time.zone_default is set, otherwise converts Date to a Time via #to_time

    # File lib/active_support/core_ext/date/zones.rb, line 7
    def to_time_in_current_zone
      if ::Time.zone
        ::Time.zone.local(year, month, day)
      else
        to_time
      end
    end

today?() click to toggle source

Returns true if the Date object’s date is today.

    # File lib/active_support/core_ext/date/calculations.rb, line 51
    def today?
      self.to_date == ::Date.current # we need the to_date because of DateTime
    end

tomorrow() click to toggle source

Convenience method which returns a new Date/DateTime representing the time 1 day since the instance time

    # File lib/active_support/core_ext/date/calculations.rb, line 273
    def tomorrow
      self + 1
    end

weeks_ago(weeks) click to toggle source

Returns a new Date/DateTime representing the time a number of specified weeks ago.

    # File lib/active_support/core_ext/date/calculations.rb, line 133
    def weeks_ago(weeks)
      advance(:weeks => -weeks)
    end

xmlschema() click to toggle source

    # File lib/active_support/core_ext/date/conversions.rb, line 103
    def xmlschema
      to_time_in_current_zone.xmlschema
    end

years_ago(years) click to toggle source

Returns a new Date/DateTime representing the time a number of specified years ago.

    # File lib/active_support/core_ext/date/calculations.rb, line 148
    def years_ago(years)
      advance(:years => -years)
    end

years_since(years) click to toggle source

Returns a new Date/DateTime representing the time a number of specified years in the future.

    # File lib/active_support/core_ext/date/calculations.rb, line 153
    def years_since(years)
      advance(:years => years)
    end

yesterday() click to toggle source

Convenience method which returns a new Date/DateTime representing the time 1 day ago

    # File lib/active_support/core_ext/date/calculations.rb, line 268
    def yesterday
      self - 1
    end