add tag v2_2_9

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/tags/v2_2_9@61257 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 682 insertions, 0 deletions

diff --git a/ruby_2_2/lib/time.rb b/ruby_2_2/lib/time.rb
new file mode 100644
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+++ b/ruby_2_2/lib/time.rb
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+require 'date'
+
+# = time.rb
+#
+# When 'time' is required, Time is extended with additional methods for parsing
+# and converting Times.
+#
+# == Features
+#
+# This library extends the Time class with the following conversions between
+# date strings and Time objects:
+#
+# * date-time defined by {RFC 2822}[http://www.ietf.org/rfc/rfc2822.txt]
+# * HTTP-date defined by {RFC 2616}[http://www.ietf.org/rfc/rfc2616.txt]
+# * dateTime defined by XML Schema Part 2: Datatypes ({ISO
+#   8601}[http://www.iso.org/iso/date_and_time_format])
+# * various formats handled by Date._parse
+# * custom formats handled by Date._strptime
+#
+# == Examples
+#
+# All examples assume you have loaded Time with:
+#
+#   require 'time'
+#
+# All of these examples were done using the EST timezone which is GMT-5.
+#
+# === Converting to a String
+#
+#   t = Time.now
+#   t.iso8601  # => "2011-10-05T22:26:12-04:00"
+#   t.rfc2822  # => "Wed, 05 Oct 2011 22:26:12 -0400"
+#   t.httpdate # => "Thu, 06 Oct 2011 02:26:12 GMT"
+#
+# === Time.parse
+#
+# #parse takes a string representation of a Time and attempts to parse it
+# using a heuristic.
+#
+#   Date.parse("2010-10-31") #=> 2010-10-31 00:00:00 -0500
+#
+# Any missing pieces of the date are inferred based on the current date.
+#
+#   # assuming the current date is "2011-10-31"
+#   Time.parse("12:00") #=> 2011-10-31 12:00:00 -0500
+#
+# We can change the date used to infer our missing elements by passing a second
+# object that responds to #mon, #day and #year, such as Date, Time or DateTime.
+# We can also use our own object.
+#
+#   class MyDate
+#     attr_reader :mon, :day, :year
+#
+#     def initialize(mon, day, year)
+#       @mon, @day, @year = mon, day, year
+#     end
+#   end
+#
+#   d  = Date.parse("2010-10-28")
+#   t  = Time.parse("2010-10-29")
+#   dt = DateTime.parse("2010-10-30")
+#   md = MyDate.new(10,31,2010)
+#
+#   Time.parse("12:00", d)  #=> 2010-10-28 12:00:00 -0500
+#   Time.parse("12:00", t)  #=> 2010-10-29 12:00:00 -0500
+#   Time.parse("12:00", dt) #=> 2010-10-30 12:00:00 -0500
+#   Time.parse("12:00", md) #=> 2010-10-31 12:00:00 -0500
+#
+# #parse also accepts an optional block. You can use this block to specify how
+# to handle the year component of the date. This is specifically designed for
+# handling two digit years. For example, if you wanted to treat all two digit
+# years prior to 70 as the year 2000+ you could write this:
+#
+#   Time.parse("01-10-31") {|year| year + (year < 70 ? 2000 : 1900)}
+#   #=> 2001-10-31 00:00:00 -0500
+#   Time.parse("70-10-31") {|year| year + (year < 70 ? 2000 : 1900)}
+#   #=> 1970-10-31 00:00:00 -0500
+#
+# === Time.strptime
+#
+# #strptime works similar to +parse+ except that instead of using a heuristic
+# to detect the format of the input string, you provide a second argument that
+# describes the format of the string. For example:
+#
+#   Time.strptime("2000-10-31", "%Y-%m-%d") #=> 2000-10-31 00:00:00 -0500
+
+class Time
+  class << Time
+
+    #
+    # A hash of timezones mapped to hour differences from UTC. The
+    # set of time zones corresponds to the ones specified by RFC 2822
+    # and ISO 8601.
+    #
+    ZoneOffset = { # :nodoc:
+      'UTC' => 0,
+      # ISO 8601
+      'Z' => 0,
+      # RFC 822
+      'UT' => 0, 'GMT' => 0,
+      'EST' => -5, 'EDT' => -4,
+      'CST' => -6, 'CDT' => -5,
+      'MST' => -7, 'MDT' => -6,
+      'PST' => -8, 'PDT' => -7,
+      # Following definition of military zones is original one.
+      # See RFC 1123 and RFC 2822 for the error in RFC 822.
+      'A' => +1, 'B' => +2, 'C' => +3, 'D' => +4,  'E' => +5,  'F' => +6,
+      'G' => +7, 'H' => +8, 'I' => +9, 'K' => +10, 'L' => +11, 'M' => +12,
+      'N' => -1, 'O' => -2, 'P' => -3, 'Q' => -4,  'R' => -5,  'S' => -6,
+      'T' => -7, 'U' => -8, 'V' => -9, 'W' => -10, 'X' => -11, 'Y' => -12,
+    }
+
+    #
+    # Return the number of seconds the specified time zone differs
+    # from UTC.
+    #
+    # Numeric time zones that include minutes, such as
+    # <code>-10:00</code> or <code>+1330</code> will work, as will
+    # simpler hour-only time zones like <code>-10</code> or
+    # <code>+13</code>.
+    #
+    # Textual time zones listed in ZoneOffset are also supported.
+    #
+    # If the time zone does not match any of the above, +zone_offset+
+    # will check if the local time zone (both with and without
+    # potential Daylight Saving \Time changes being in effect) matches
+    # +zone+. Specifying a value for +year+ will change the year used
+    # to find the local time zone.
+    #
+    # If +zone_offset+ is unable to determine the offset, nil will be
+    # returned.
+    def zone_offset(zone, year=self.now.year)
+      off = nil
+      zone = zone.upcase
+      if /\A([+-])(\d\d):?(\d\d)\z/ =~ zone
+        off = ($1 == '-' ? -1 : 1) * ($2.to_i * 60 + $3.to_i) * 60
+      elsif /\A[+-]\d\d\z/ =~ zone
+        off = zone.to_i * 3600
+      elsif ZoneOffset.include?(zone)
+        off = ZoneOffset[zone] * 3600
+      elsif ((t = self.local(year, 1, 1)).zone.upcase == zone rescue false)
+        off = t.utc_offset
+      elsif ((t = self.local(year, 7, 1)).zone.upcase == zone rescue false)
+        off = t.utc_offset
+      end
+      off
+    end
+
+    def zone_utc?(zone)
+      # * +0000
+      #   In RFC 2822, +0000 indicate a time zone at Universal Time.
+      #   Europe/Lisbon is "a time zone at Universal Time" in Winter.
+      #   Atlantic/Reykjavik is "a time zone at Universal Time".
+      #   Africa/Dakar is "a time zone at Universal Time".
+      #   So +0000 is a local time such as Europe/London, etc.
+      # * GMT
+      #   GMT is used as a time zone abbreviation in Europe/London,
+      #   Africa/Dakar, etc.
+      #   So it is a local time.
+      #
+      # * -0000, -00:00
+      #   In RFC 2822, -0000 the date-time contains no information about the
+      #   local time zone.
+      #   In RFC 3339, -00:00 is used for the time in UTC is known,
+      #   but the offset to local time is unknown.
+      #   They are not appropriate for specific time zone such as
+      #   Europe/London because time zone neutral,
+      #   So -00:00 and -0000 are treated as UTC.
+      if /\A(?:-00:00|-0000|-00|UTC|Z|UT)\z/i =~ zone
+        true
+      else
+        false
+      end
+    end
+    private :zone_utc?
+
+    def force_zone!(t, zone, offset=nil)
+      if zone_utc?(zone)
+        t.utc
+      elsif offset ||= zone_offset(zone)
+        # Prefer the local timezone over the fixed offset timezone because
+        # the former is a real timezone and latter is an artificial timezone.
+        t.localtime
+        if t.utc_offset != offset
+          # Use the fixed offset timezone only if the local timezone cannot
+          # represent the given offset.
+          t.localtime(offset)
+        end
+      else
+        t.localtime
+      end
+    end
+    private :force_zone!
+
+    LeapYearMonthDays = [31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31] # :nodoc:
+    CommonYearMonthDays = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31] # :nodoc:
+    def month_days(y, m)
+      if ((y % 4 == 0) && (y % 100 != 0)) || (y % 400 == 0)
+        LeapYearMonthDays[m-1]
+      else
+        CommonYearMonthDays[m-1]
+      end
+    end
+    private :month_days
+
+    def apply_offset(year, mon, day, hour, min, sec, off)
+      if off < 0
+        off = -off
+        off, o = off.divmod(60)
+        if o != 0 then sec += o; o, sec = sec.divmod(60); off += o end
+        off, o = off.divmod(60)
+        if o != 0 then min += o; o, min = min.divmod(60); off += o end
+        off, o = off.divmod(24)
+        if o != 0 then hour += o; o, hour = hour.divmod(24); off += o end
+        if off != 0
+          day += off
+          days = month_days(year, mon)
+          if days and days < day
+            mon += 1
+            if 12 < mon
+              mon = 1
+              year += 1
+            end
+            day = 1
+          end
+        end
+      elsif 0 < off
+        off, o = off.divmod(60)
+        if o != 0 then sec -= o; o, sec = sec.divmod(60); off -= o end
+        off, o = off.divmod(60)
+        if o != 0 then min -= o; o, min = min.divmod(60); off -= o end
+        off, o = off.divmod(24)
+        if o != 0 then hour -= o; o, hour = hour.divmod(24); off -= o end
+        if off != 0 then
+          day -= off
+          if day < 1
+            mon -= 1
+            if mon < 1
+              year -= 1
+              mon = 12
+            end
+            day = month_days(year, mon)
+          end
+        end
+      end
+      return year, mon, day, hour, min, sec
+    end
+    private :apply_offset
+
+    def make_time(date, year, mon, day, hour, min, sec, sec_fraction, zone, now)
+      if !year && !mon && !day && !hour && !min && !sec && !sec_fraction
+        raise ArgumentError, "no time information in #{date.inspect}"
+      end
+
+      off_year = year || now.year
+      off = nil
+      off = zone_offset(zone, off_year) if zone
+
+      if off
+        now = now.getlocal(off) if now.utc_offset != off
+      else
+        now = now.getlocal
+      end
+
+      usec = nil
+      usec = sec_fraction * 1000000 if sec_fraction
+
+      if now
+        begin
+          break if year; year = now.year
+          break if mon; mon = now.mon
+          break if day; day = now.day
+          break if hour; hour = now.hour
+          break if min; min = now.min
+          break if sec; sec = now.sec
+          break if sec_fraction; usec = now.tv_usec
+        end until true
+      end
+
+      year ||= 1970
+      mon ||= 1
+      day ||= 1
+      hour ||= 0
+      min ||= 0
+      sec ||= 0
+      usec ||= 0
+
+      if year != off_year
+        off = nil
+        off = zone_offset(zone, year) if zone
+      end
+
+      if off
+        year, mon, day, hour, min, sec =
+          apply_offset(year, mon, day, hour, min, sec, off)
+        t = self.utc(year, mon, day, hour, min, sec, usec)
+        force_zone!(t, zone, off)
+        t
+      else
+        self.local(year, mon, day, hour, min, sec, usec)
+      end
+    end
+    private :make_time
+
+    #
+    # Parses +date+ using Date._parse and converts it to a Time object.
+    #
+    # If a block is given, the year described in +date+ is converted by the
+    # block.  For example:
+    #
+    #     Time.parse(...) {|y| 0 <= y && y < 100 ? (y >= 69 ? y + 1900 : y + 2000) : y}
+    #
+    # If the upper components of the given time are broken or missing, they are
+    # supplied with those of +now+.  For the lower components, the minimum
+    # values (1 or 0) are assumed if broken or missing.  For example:
+    #
+    #     # Suppose it is "Thu Nov 29 14:33:20 2001" now and
+    #     # your time zone is EST which is GMT-5.
+    #     now = Time.parse("Thu Nov 29 14:33:20 2001")
+    #     Time.parse("16:30", now)     #=> 2001-11-29 16:30:00 -0500
+    #     Time.parse("7/23", now)      #=> 2001-07-23 00:00:00 -0500
+    #     Time.parse("Aug 31", now)    #=> 2001-08-31 00:00:00 -0500
+    #     Time.parse("Aug 2000", now)  #=> 2000-08-01 00:00:00 -0500
+    #
+    # Since there are numerous conflicts among locally defined time zone
+    # abbreviations all over the world, this method is not intended to
+    # understand all of them.  For example, the abbreviation "CST" is
+    # used variously as:
+    #
+    #     -06:00 in America/Chicago,
+    #     -05:00 in America/Havana,
+    #     +08:00 in Asia/Harbin,
+    #     +09:30 in Australia/Darwin,
+    #     +10:30 in Australia/Adelaide,
+    #     etc.
+    #
+    # Based on this fact, this method only understands the time zone
+    # abbreviations described in RFC 822 and the system time zone, in the
+    # order named. (i.e. a definition in RFC 822 overrides the system
+    # time zone definition.)  The system time zone is taken from
+    # <tt>Time.local(year, 1, 1).zone</tt> and
+    # <tt>Time.local(year, 7, 1).zone</tt>.
+    # If the extracted time zone abbreviation does not match any of them,
+    # it is ignored and the given time is regarded as a local time.
+    #
+    # ArgumentError is raised if Date._parse cannot extract information from
+    # +date+ or if the Time class cannot represent specified date.
+    #
+    # This method can be used as a fail-safe for other parsing methods as:
+    #
+    #   Time.rfc2822(date) rescue Time.parse(date)
+    #   Time.httpdate(date) rescue Time.parse(date)
+    #   Time.xmlschema(date) rescue Time.parse(date)
+    #
+    # A failure of Time.parse should be checked, though.
+    #
+    # You must require 'time' to use this method.
+    #
+    def parse(date, now=self.now)
+      comp = !block_given?
+      d = Date._parse(date, comp)
+      year = d[:year]
+      year = yield(year) if year && !comp
+      make_time(date, year, d[:mon], d[:mday], d[:hour], d[:min], d[:sec], d[:sec_fraction], d[:zone], now)
+    end
+
+    #
+    # Parses +date+ using Date._strptime and converts it to a Time object.
+    #
+    # If a block is given, the year described in +date+ is converted by the
+    # block.  For example:
+    #
+    #   Time.strptime(...) {|y| y < 100 ? (y >= 69 ? y + 1900 : y + 2000) : y}
+    #
+    # Below is a list of the formatting options:
+    #
+    # %a :: The abbreviated weekday name ("Sun")
+    # %A :: The  full  weekday  name ("Sunday")
+    # %b :: The abbreviated month name ("Jan")
+    # %B :: The  full  month  name ("January")
+    # %c :: The preferred local date and time representation
+    # %C :: Century (20 in 2009)
+    # %d :: Day of the month (01..31)
+    # %D :: Date (%m/%d/%y)
+    # %e :: Day of the month, blank-padded ( 1..31)
+    # %F :: Equivalent to %Y-%m-%d (the ISO 8601 date format)
+    # %h :: Equivalent to %b
+    # %H :: Hour of the day, 24-hour clock (00..23)
+    # %I :: Hour of the day, 12-hour clock (01..12)
+    # %j :: Day of the year (001..366)
+    # %k :: hour, 24-hour clock, blank-padded ( 0..23)
+    # %l :: hour, 12-hour clock, blank-padded ( 0..12)
+    # %L :: Millisecond of the second (000..999)
+    # %m :: Month of the year (01..12)
+    # %M :: Minute of the hour (00..59)
+    # %n :: Newline (\n)
+    # %N :: Fractional seconds digits, default is 9 digits (nanosecond)
+    #       %3N :: millisecond (3 digits)
+    #       %6N :: microsecond (6 digits)
+    #       %9N :: nanosecond (9 digits)
+    # %p :: Meridian indicator ("AM" or "PM")
+    # %P :: Meridian indicator ("am" or "pm")
+    # %r :: time, 12-hour (same as %I:%M:%S %p)
+    # %R :: time, 24-hour (%H:%M)
+    # %s :: Number of seconds since 1970-01-01 00:00:00 UTC.
+    # %S :: Second of the minute (00..60)
+    # %t :: Tab character (\t)
+    # %T :: time, 24-hour (%H:%M:%S)
+    # %u :: Day of the week as a decimal, Monday being 1. (1..7)
+    # %U :: Week number of the current year, starting with the first Sunday as
+    #       the first day of the first week (00..53)
+    # %v :: VMS date (%e-%b-%Y)
+    # %V :: Week number of year according to ISO 8601 (01..53)
+    # %W :: Week  number  of the current year, starting with the first Monday
+    #       as the first day of the first week (00..53)
+    # %w :: Day of the week (Sunday is 0, 0..6)
+    # %x :: Preferred representation for the date alone, no time
+    # %X :: Preferred representation for the time alone, no date
+    # %y :: Year without a century (00..99)
+    # %Y :: Year which may include century, if provided
+    # %z :: Time zone as  hour offset from UTC (e.g. +0900)
+    # %Z :: Time zone name
+    # %% :: Literal "%" character
+
+    def strptime(date, format, now=self.now)
+      d = Date._strptime(date, format)
+      raise ArgumentError, "invalid strptime format - `#{format}'" unless d
+      if seconds = d[:seconds]
+        if sec_fraction = d[:sec_fraction]
+          usec = sec_fraction * 1000000
+          usec *= -1 if seconds < 0
+        else
+          usec = 0
+        end
+        t = Time.at(seconds, usec)
+        if zone = d[:zone]
+          force_zone!(t, zone)
+        end
+      else
+        year = d[:year]
+        year = yield(year) if year && block_given?
+        t = make_time(date, year, d[:mon], d[:mday], d[:hour], d[:min], d[:sec], d[:sec_fraction], d[:zone], now)
+      end
+      t
+    end
+
+    MonthValue = { # :nodoc:
+      'JAN' => 1, 'FEB' => 2, 'MAR' => 3, 'APR' => 4, 'MAY' => 5, 'JUN' => 6,
+      'JUL' => 7, 'AUG' => 8, 'SEP' => 9, 'OCT' =>10, 'NOV' =>11, 'DEC' =>12
+    }
+
+    #
+    # Parses +date+ as date-time defined by RFC 2822 and converts it to a Time
+    # object.  The format is identical to the date format defined by RFC 822 and
+    # updated by RFC 1123.
+    #
+    # ArgumentError is raised if +date+ is not compliant with RFC 2822
+    # or if the Time class cannot represent specified date.
+    #
+    # See #rfc2822 for more information on this format.
+    #
+    # You must require 'time' to use this method.
+    #
+    def rfc2822(date)
+      if /\A\s*
+          (?:(?:Mon|Tue|Wed|Thu|Fri|Sat|Sun)\s*,\s*)?
+          (\d{1,2})\s+
+          (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)\s+
+          (\d{2,})\s+
+          (\d{2})\s*
+          :\s*(\d{2})\s*
+          (?::\s*(\d{2}))?\s+
+          ([+-]\d{4}|
+           UT|GMT|EST|EDT|CST|CDT|MST|MDT|PST|PDT|[A-IK-Z])/ix =~ date
+        # Since RFC 2822 permit comments, the regexp has no right anchor.
+        day = $1.to_i
+        mon = MonthValue[$2.upcase]
+        year = $3.to_i
+        short_year_p = $3.length <= 3
+        hour = $4.to_i
+        min = $5.to_i
+        sec = $6 ? $6.to_i : 0
+        zone = $7
+
+        if short_year_p
+          # following year completion is compliant with RFC 2822.
+          year = if year < 50
+                   2000 + year
+                 else
+                   1900 + year
+                 end
+        end
+
+        off = zone_offset(zone)
+        year, mon, day, hour, min, sec =
+          apply_offset(year, mon, day, hour, min, sec, off)
+        t = self.utc(year, mon, day, hour, min, sec)
+        force_zone!(t, zone, off)
+        t
+      else
+        raise ArgumentError.new("not RFC 2822 compliant date: #{date.inspect}")
+      end
+    end
+    alias rfc822 rfc2822
+
+    #
+    # Parses +date+ as an HTTP-date defined by RFC 2616 and converts it to a
+    # Time object.
+    #
+    # ArgumentError is raised if +date+ is not compliant with RFC 2616 or if
+    # the Time class cannot represent specified date.
+    #
+    # See #httpdate for more information on this format.
+    #
+    # You must require 'time' to use this method.
+    #
+    def httpdate(date)
+      if /\A\s*
+          (?:Mon|Tue|Wed|Thu|Fri|Sat|Sun),\x20
+          (\d{2})\x20
+          (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)\x20
+          (\d{4})\x20
+          (\d{2}):(\d{2}):(\d{2})\x20
+          GMT
+          \s*\z/ix =~ date
+        self.rfc2822(date).utc
+      elsif /\A\s*
+             (?:Monday|Tuesday|Wednesday|Thursday|Friday|Saturday|Sunday),\x20
+             (\d\d)-(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)-(\d\d)\x20
+             (\d\d):(\d\d):(\d\d)\x20
+             GMT
+             \s*\z/ix =~ date
+        year = $3.to_i
+        if year < 50
+          year += 2000
+        else
+          year += 1900
+        end
+        self.utc(year, $2, $1.to_i, $4.to_i, $5.to_i, $6.to_i)
+      elsif /\A\s*
+             (?:Mon|Tue|Wed|Thu|Fri|Sat|Sun)\x20
+             (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)\x20
+             (\d\d|\x20\d)\x20
+             (\d\d):(\d\d):(\d\d)\x20
+             (\d{4})
+             \s*\z/ix =~ date
+        self.utc($6.to_i, MonthValue[$1.upcase], $2.to_i,
+                 $3.to_i, $4.to_i, $5.to_i)
+      else
+        raise ArgumentError.new("not RFC 2616 compliant date: #{date.inspect}")
+      end
+    end
+
+    #
+    # Parses +date+ as a dateTime defined by the XML Schema and converts it to
+    # a Time object.  The format is a restricted version of the format defined
+    # by ISO 8601.
+    #
+    # ArgumentError is raised if +date+ is not compliant with the format or if
+    # the Time class cannot represent specified date.
+    #
+    # See #xmlschema for more information on this format.
+    #
+    # You must require 'time' to use this method.
+    #
+    def xmlschema(date)
+      if /\A\s*
+          (-?\d+)-(\d\d)-(\d\d)
+          T
+          (\d\d):(\d\d):(\d\d)
+          (\.\d+)?
+          (Z|[+-]\d\d:\d\d)?
+          \s*\z/ix =~ date
+        year = $1.to_i
+        mon = $2.to_i
+        day = $3.to_i
+        hour = $4.to_i
+        min = $5.to_i
+        sec = $6.to_i
+        usec = 0
+        if $7
+          usec = Rational($7) * 1000000
+        end
+        if $8
+          zone = $8
+          off = zone_offset(zone)
+          year, mon, day, hour, min, sec =
+            apply_offset(year, mon, day, hour, min, sec, off)
+          t = self.utc(year, mon, day, hour, min, sec, usec)
+          force_zone!(t, zone, off)
+          t
+        else
+          self.local(year, mon, day, hour, min, sec, usec)
+        end
+      else
+        raise ArgumentError.new("invalid date: #{date.inspect}")
+      end
+    end
+    alias iso8601 xmlschema
+  end # class << self
+
+  #
+  # Returns a string which represents the time as date-time defined by RFC 2822:
+  #
+  #   day-of-week, DD month-name CCYY hh:mm:ss zone
+  #
+  # where zone is [+-]hhmm.
+  #
+  # If +self+ is a UTC time, -0000 is used as zone.
+  #
+  # You must require 'time' to use this method.
+  #
+  def rfc2822
+    sprintf('%s, %02d %s %0*d %02d:%02d:%02d ',
+      RFC2822_DAY_NAME[wday],
+      day, RFC2822_MONTH_NAME[mon-1], year < 0 ? 5 : 4, year,
+      hour, min, sec) +
+    if utc?
+      '-0000'
+    else
+      off = utc_offset
+      sign = off < 0 ? '-' : '+'
+      sprintf('%s%02d%02d', sign, *(off.abs / 60).divmod(60))
+    end
+  end
+  alias rfc822 rfc2822
+
+
+  RFC2822_DAY_NAME = [ # :nodoc:
+    'Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'
+  ]
+
+  RFC2822_MONTH_NAME = [ # :nodoc:
+    'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
+    'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'
+  ]
+
+  #
+  # Returns a string which represents the time as RFC 1123 date of HTTP-date
+  # defined by RFC 2616:
+  #
+  #   day-of-week, DD month-name CCYY hh:mm:ss GMT
+  #
+  # Note that the result is always UTC (GMT).
+  #
+  # You must require 'time' to use this method.
+  #
+  def httpdate
+    t = dup.utc
+    sprintf('%s, %02d %s %0*d %02d:%02d:%02d GMT',
+      RFC2822_DAY_NAME[t.wday],
+      t.day, RFC2822_MONTH_NAME[t.mon-1], t.year < 0 ? 5 : 4, t.year,
+      t.hour, t.min, t.sec)
+  end
+
+  #
+  # Returns a string which represents the time as a dateTime defined by XML
+  # Schema:
+  #
+  #   CCYY-MM-DDThh:mm:ssTZD
+  #   CCYY-MM-DDThh:mm:ss.sssTZD
+  #
+  # where TZD is Z or [+-]hh:mm.
+  #
+  # If self is a UTC time, Z is used as TZD.  [+-]hh:mm is used otherwise.
+  #
+  # +fractional_digits+ specifies a number of digits to use for fractional
+  # seconds.  Its default value is 0.
+  #
+  # You must require 'time' to use this method.
+  #
+  def xmlschema(fraction_digits=0)
+    fraction_digits = fraction_digits.to_i
+    s = strftime("%FT%T")
+    if fraction_digits > 0
+      s << strftime(".%#{fraction_digits}N")
+    end
+    s << (utc? ? 'Z' : strftime("%:z"))
+  end
+  alias iso8601 xmlschema
+end
+