Module: Holidays

Included in:
Date
Defined in:
lib/holidays.rb,
lib/holidays/ar.rb,
lib/holidays/at.rb,
lib/holidays/au.rb,
lib/holidays/be.rb,
lib/holidays/br.rb,
lib/holidays/ca.rb,
lib/holidays/ch.rb,
lib/holidays/cl.rb,
lib/holidays/cr.rb,
lib/holidays/cz.rb,
lib/holidays/de.rb,
lib/holidays/dk.rb,
lib/holidays/el.rb,
lib/holidays/es.rb,
lib/holidays/fi.rb,
lib/holidays/fr.rb,
lib/holidays/gb.rb,
lib/holidays/hr.rb,
lib/holidays/hu.rb,
lib/holidays/ie.rb,
lib/holidays/is.rb,
lib/holidays/it.rb,
lib/holidays/jp.rb,
lib/holidays/li.rb,
lib/holidays/lt.rb,
lib/holidays/ma.rb,
lib/holidays/mx.rb,
lib/holidays/nl.rb,
lib/holidays/no.rb,
lib/holidays/nz.rb,
lib/holidays/ph.rb,
lib/holidays/pl.rb,
lib/holidays/pt.rb,
lib/holidays/ro.rb,
lib/holidays/se.rb,
lib/holidays/sg.rb,
lib/holidays/si.rb,
lib/holidays/sk.rb,
lib/holidays/us.rb,
lib/holidays/ve.rb,
lib/holidays/vi.rb,
lib/holidays/za.rb,
lib/holidays/ups.rb,
lib/holidays/nerc.rb,
lib/holidays/nyse.rb,
lib/holidays/europe.rb,
lib/holidays/fed_ex.rb,
lib/holidays/version.rb,
lib/holidays/ecb_target.rb,
lib/holidays/scandinavia.rb,
lib/holidays/north_america.rb,
lib/holidays/united_nations.rb,
lib/holidays/federal_reserve.rb

Overview

Region options

Holidays can be defined as belonging to one or more regions and sub regions. The Holidays#on, Holidays#between, Date#holidays and Date#holiday? methods each allow you to specify a specific region.

There are several different ways that you can specify a region:

:region

By region. For example, return holidays in the Canada with :ca.

:region_

By region and sub regions. For example, return holidays in Germany and all its sub regions with :de_.

:region_sub

By sub region. Return national holidays in Spain plus holidays in Spain’s Valencia region with :es_v.

:any

Any region. Return holidays from any loaded region.

You can load all the available holiday definition sets by running

Holidays.load_all

Other options

:observed

Return holidays on the day they are observed (e.g. on a Monday if they fall on a Sunday).

:informal

Include informal holidays (e.g. Valentine’s Day)

Examples

Return all holidays in the :ca and :us regions on the day that they are observed.

Holidays.between(from, to, :ca, :us, :observed)

Return all holidays in :ca and any :ca sub-region.

Holidays.between(from, to, :ca_)

Return all holidays in :ca_bc sub-region (which includes the :ca), including informal holidays.

Holidays.between(from, to, :ca_bc, :informal)

Defined Under Namespace

Modules: AR, AT, AU, BE, BR, CA, CH, CL, CR, CZ, DE, DK, ECB_TARGET, EL, ES, EUROPE, FEDERAL_RESERVE, FED_EX, FI, FR, GB, HR, HU, IE, IS, IT, JP, LI, LT, MA, MX, NERC, NL, NO, NORTH_AMERICA, NYSE, NZ, PH, PL, PT, RO, SCANDINAVIA, SE, SG, SI, SK, UNITED_NATIONS, UPS, US, VE, VI, ZA Classes: UnknownRegionError

Constant Summary collapse

WEEKS =
{:first => 1, :second => 2, :third => 3, :fourth => 4, :fifth => 5, :last => -1, :second_last => -2, :third_last => -3}
MONTH_LENGTHS =
[31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
DAY_SYMBOLS =
Date::DAYNAMES.collect { |n| n.downcase.intern }
DEFINITION_PATH =
File.expand_path(File.dirname(__FILE__) + '/holidays/')
VERSION =
'2.0.0'
@@regions =
[]
@@holidays_by_month =
{}
@@proc_cache =
{}
@@cache =
{}
@@cache_range =
{}

Class Method Summary collapse

Class Method Details

.available(full_path = false) ⇒ Object

Returns an array of symbols all the available holiday definitions.

Optional ‘full_path` param is used internally for loading all the definitions.



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# File 'lib/holidays.rb', line 312

def self.available(full_path = false)
  paths = Dir.glob(DEFINITION_PATH + '/*.rb')
  full_path ? paths : paths.collect { |path| path.match(/([a-z_-]+)\.rb/i)[1].to_sym }
end

.between(start_date, end_date, *options) ⇒ Object

Get all holidays occuring between two dates, inclusively.

Returns an array of hashes or nil.

Each holiday is returned as a hash with the following fields:

start_date

Ruby Date object.

end_date

Ruby Date object.

options

One or more region symbols, :informal and/or :observed.

Example

from = Date.civil(2008,7,1)
to   = Date.civil(2008,7,31)

Holidays.between(from, to, :ca, :us)
=> [{:name => 'Canada Day', :regions => [:ca]...}
    {:name => 'Independence Day'', :regions => [:us], ...}]


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# File 'lib/holidays.rb', line 112

def self.between(start_date, end_date, *options)
  # remove the timezone
  start_date = start_date.new_offset(0) + start_date.offset if start_date.respond_to?(:new_offset)
  end_date = end_date.new_offset(0) + end_date.offset if end_date.respond_to?(:new_offset)

  # get simple dates
  start_date, end_date = get_date(start_date), get_date(end_date)

  if range = @@cache_range[options]
    if range.begin < start_date && range.end > end_date
      return @@cache[options].select do |holiday|
        holiday[:date] >= start_date && holiday[:date] <= end_date
      end
    end
  end

  regions, observed, informal = parse_options(options)
  holidays = []

  dates = {}
  (start_date..end_date).each do |date|
    # Always include month '0' for variable-month holidays
    dates[date.year] = [0] unless dates[date.year]
    # TODO: test this, maybe should push then flatten
    dates[date.year] << date.month unless dates[date.year].include?(date.month)
  end

  dates.each do |year, months|
    months.each do |month|
      next unless hbm = @@holidays_by_month[month]

      hbm.each do |h|
        next unless in_region?(regions, h[:regions])

        # Skip informal holidays unless they have been requested
        next if h[:type] == :informal and not informal

        if h[:function]
          # Holiday definition requires a calculation
          result = call_proc(h[:function], year)

          # Procs may return either Date or an integer representing mday
          if result.kind_of?(Date)
            month = result.month
            mday = result.mday
          else
            mday = result
          end
        else
          # Calculate the mday
          mday = h[:mday] || Date.calculate_mday(year, month, h[:week], h[:wday])
        end

        # Silently skip bad mdays
        begin
          date = Date.civil(year, month, mday)
        rescue; next; end

        # If the :observed option is set, calculate the date when the holiday
        # is observed.
        if observed and h[:observed]
          date = call_proc(h[:observed], date)
        end

        if date.between?(start_date, end_date)
          holidays << {:date => date, :name => h[:name], :regions => h[:regions]}
        end

      end
    end
  end

  holidays.sort{|a, b| a[:date] <=> b[:date] }
end

.ca_victoria_day(year) ⇒ Object

Monday on or before May 24



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# File 'lib/holidays/ca.rb', line 66

def self.ca_victoria_day(year)
  date = Date.civil(year,5,24)
  if date.wday > 1
    date -= (date.wday - 1)
  elsif date.wday == 0
    date -= 6
  end
  date
end

.cacheObject



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# File 'lib/holidays.rb', line 58

def cache; @@cache; end

.cache_between(start_date, end_date, *options) ⇒ Object

Allows a developer to explicitly calculate and cache holidays within a given period



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# File 'lib/holidays.rb', line 188

def self.cache_between(start_date, end_date, *options)
  start_date, end_date = get_date(start_date), get_date(end_date)
  @@cache[options]       = between(start_date, end_date, *options)
  @@cache_range[options] = start_date..end_date
end

.cache_rangeObject



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# File 'lib/holidays.rb', line 57

def cache_range; @@cache_range; end

.ch_ge_jeune_genevois(year) ⇒ Object

Thursday after the first Sunday of September



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# File 'lib/holidays/ch.rb', line 64

def self.ch_ge_jeune_genevois(year)
  date = Date.civil(year,9,1)
  # Find the first Sunday of September
  until date.wday.eql? 0 do
    date += 1
  end
  # Thursday is four days after Sunday
  date + 4
end

.ch_gl_naefelser_fahrt(year) ⇒ Object

First Thursday of April. If the first Thursday of April is in the week before easter, then a week later.



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# File 'lib/holidays/ch.rb', line 76

def self.ch_gl_naefelser_fahrt(year)
  date = Date.civil(year,4,1)
  # Find the first Thursday of April
  until date.wday.eql? 4 do
    date += 1
  end
  if date.eql?(easter(year)-3)
    date += 7
  end
  date
end

.ch_vd_lundi_du_jeune_federal(year) ⇒ Object

Monday after the third Sunday of September



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# File 'lib/holidays/ch.rb', line 51

def self.ch_vd_lundi_du_jeune_federal(year)
  date = Date.civil(year,9,1)
  # Find the first Sunday of September
  until date.wday.eql? 0 do
    date += 1
  end
  # There are 15 days between the first Sunday
  # and the Monday after the third Sunday
  date + 15
end

.closest_monday(date) ⇒ Object



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# File 'lib/holidays/nz.rb', line 49

def self.closest_monday(date)
  if [1, 2, 3, 4].include?(date.wday)
    date -= (date.wday - 1)
  elsif 0 == date.wday
    date += 1
  else
    date += 8 - date.wday
  end
  date
end

.de_buss_und_bettag(year) ⇒ Object

Germany: Wednesday before November 23



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# File 'lib/holidays/de.rb', line 41

def self.de_buss_und_bettag(year)
  date = Date.civil(year,11,23)
  if date.wday > 3
    date -= (date.wday - 3)
  else
    date -= (date.wday + 4)
  end
  date
end

.easter(year) ⇒ Object

Get the date of Easter Sunday in a given year. From Easter Sunday, it is possible to calculate many traditional holidays in Western countries. Returns a Date object.



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# File 'lib/holidays.rb', line 228

def self.easter(year)
  y = year
  a = y % 19
  b = y / 100
  c = y % 100
  d = b / 4
  e = b % 4
  f = (b + 8) / 25
  g = (b - f + 1) / 3
  h = (19 * a + b - d - g + 15) % 30
  i = c / 4
  k = c % 4
  l = (32 + 2 * e + 2 * i - h - k) % 7
  m = (a + 11 * h + 22 * l) / 451
  month = (h + l - 7 * m + 114) / 31
  day = ((h + l - 7 * m + 114) % 31) + 1
  Date.civil(year, month, day)
end

.fi_juhannusaatto(year) ⇒ Object

Finland: Mid-summer eve (Friday between June 19–25)



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# File 'lib/holidays/fi.rb', line 41

def self.fi_juhannusaatto(year)
  date = Date.civil(year,6,19)
  if date.wday > 5 #if 19.6 is saturday
    date += 6
  else 
    date += (5 - date.wday)
  end
  date
end

.fi_juhannuspaiva(year) ⇒ Object

Finland: Mid-summer (Saturday between June 20–26)



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# File 'lib/holidays/fi.rb', line 53

def self.fi_juhannuspaiva(year)
  date = Date.civil(year,6,20)
  date += (6 - date.wday)
  date
end

.fi_pyhainpaiva(year) ⇒ Object

Finland: All Saint’s Day (Saturday between Oct 31 and Nov 6)



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# File 'lib/holidays/fi.rb', line 61

def self.fi_pyhainpaiva(year)
  date = Date.civil(year,10,31)
  date += (6 - date.wday)
  date
end

.full_week?(date, *options) ⇒ Boolean

Does the given work-week have any holidays?

date

A Date object.

:options

One or more region symbols, and/or :informal. Automatically includes :observed. If you don’t want this, pass :no_observed

The given Date can be any day of the week. Returns true if any holidays fall on Monday - Friday of the given week.

Returns:

  • (Boolean)


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# File 'lib/holidays.rb', line 86

def self.full_week?(date, *options)
  days_to_monday = date.wday - 1
  days_to_friday = 5 - date.wday
  start_date = date - days_to_monday
  end_date = date + days_to_friday
  options += [:observed] unless options.include?(:no_observed)
  options.delete(:no_observed)
  self.between(start_date, end_date, options).empty?
end

.g20_day_2014_only(year) ⇒ Object



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# File 'lib/holidays/au.rb', line 78

def self.g20_day_2014_only(year)
  year == 2014 ? 14 : nil
end

.hobart_show_day(year) ⇒ Object

worksafe.tas.gov.au/__data/assets/pdf_file/0008/287036/Public_Holidays_2014.pdf The Thursday before the fourth Saturday in October.



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# File 'lib/holidays/au.rb', line 85

def self.hobart_show_day(year)
  fourth_sat_in_oct = Date.civil(year, 10, Date.calculate_mday(year, 10, 4, :saturday))
  fourth_sat_in_oct - 2 # the thursday before
end

.ie_st_stephens_day(date) ⇒ Object

Ireland - Stephens Day is always the day after christmas day



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# File 'lib/holidays/ie.rb', line 35

def self.ie_st_stephens_day(date)
  date += 2 if date.wday == 6
  date += 2 if date.wday == 0
  date += 1 if date.wday == 1
  date
end

.is_sumardagurinn_fyrsti(year) ⇒ Object

Iceland: first day of summer (Thursday after 18 April)



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# File 'lib/holidays/is.rb', line 52

def self.is_sumardagurinn_fyrsti(year)
  date = Date.civil(year,4,18)
  if date.wday < 4
    date += (4 - date.wday)
  else date
    date += (11 - date.wday)
  end
  date
end

.jp_citizons_holiday(year) ⇒ Object



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# File 'lib/holidays/jp.rb', line 94

def self.jp_citizons_holiday(year)
  year < 2003 and return nil
  ncd = Holidays.jp_national_culture_day(year)
  if ncd.wday == 3
    ncd - 1
  else
    nil
  end
end

.jp_national_culture_day(year) ⇒ Object



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# File 'lib/holidays/jp.rb', line 74

def self.jp_national_culture_day(year)
  day =
    case year
    when 1851..1899
      22.2588
    when 1900..1979
      23.2588
    when 1980..2099
      23.2488
    when 2100..2150
      24.2488
    else
      raise IndexError.new("Out of range")
    end
  day += 0.242194 * (year - 1980) - ((year - 1980)/4).floor
  day = day.floor
  Date.civil(year, 9, day)
end

.jp_substitute_holiday(*date) ⇒ Object



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# File 'lib/holidays/jp.rb', line 105

def self.jp_substitute_holiday(*date)
  date = date[0].kind_of?(Date) ? date.first : Date.civil(*date)
  date.wday == 0 ? date+1 : nil
end

.jp_vernal_equinox_day(year) ⇒ Object



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# File 'lib/holidays/jp.rb', line 54

def self.jp_vernal_equinox_day(year)
  day =
    case year
    when 1851..1899
      19.8277
    when 1900..1979
      20.8357
    when 1980..2099
      20.8431
    when 2100..2150
      21.8510
    else
      raise IndexError.new("Out of range")
    end
  day += 0.242194 * (year - 1980) - ((year - 1980)/4).floor
  day = day.floor
  Date.civil(year, 3, day)
end

.load_allObject

Load all available holiday definitions



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# File 'lib/holidays.rb', line 323

def self.load_all
  self.available(true).each { |path| require path }
end

.load_custom(*files) ⇒ Object

Parses provided holiday definition file(s) and loads them so that they are immediately available.



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# File 'lib/holidays.rb', line 328

def self.load_custom(*files)
  regions, rules_by_month, custom_methods, tests = self.parse_definition_files(files)
  merge_defs(regions, rules_by_month)
end

.merge_defs(regions, holidays) ⇒ Object

Merge a new set of definitions into the Holidays module.

This method is automatically called when including holiday definition files.



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# File 'lib/holidays.rb', line 198

def self.merge_defs(regions, holidays) # :nodoc:
  @@regions = @@regions | regions
  @@regions.uniq!

  holidays.each do |month, holiday_defs|
    @@holidays_by_month[month] = [] unless @@holidays_by_month[month]
    holiday_defs.each do |holiday_def|

        exists = false
        @@holidays_by_month[month].each do |ex|
          # TODO: gross.
          if ex[:name] == holiday_def[:name] and ex[:wday] == holiday_def[:wday] and ex[:mday] == holiday_def[:mday] and ex[:week] == holiday_def[:week] and ex[:function_id] == holiday_def[:function_id] and ex[:type] == holiday_def[:type] and ex[:observed_id] == holiday_def[:observed_id]
            # append regions
            ex[:regions] << holiday_def[:regions]

            # Should do this once we're done
            ex[:regions].flatten!
            ex[:regions].uniq!
            exists = true
          end
        end

        @@holidays_by_month[month] << holiday_def  unless exists
    end
  end
end

.next_week(date) ⇒ Object



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# File 'lib/holidays/nz.rb', line 66

def self.next_week(date)
  date + 7
end

.on(date, *options) ⇒ Object

Get all holidays on a given date.

date

A Date object.

:options

One or more region symbols, :informal and/or :observed.

Returns an array of hashes or nil. See Holidays#between for the output format.

Also available via Date#holidays.



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# File 'lib/holidays.rb', line 75

def self.on(date, *options)
  self.between(date, date, options)
end

.orthodox_easter(year) ⇒ Object

A method to calculate the orthodox easter date, returns date in the Gregorian (western) calendar Safe until appr. 4100 AD, when one leap day will be removed. Returns a Date object.



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# File 'lib/holidays.rb', line 250

def self.orthodox_easter(year)
  y = year
  g = y % 19
  i = (19 * g + 15) % 30
  j = (year + year/4 + i) % 7
  j_month = 3 + (i - j + 40) / 44
  j_day = i - j + 28 - 31 * (j_month / 4)
  j_date = Date.civil(year, j_month, j_day)
  case
    # up until 1582, julian and gregorian easter dates were identical
    when year <= 1582
      offset = 0
    # between the years 1583 and 1699 10 days are added to the julian day count
    when (year >= 1583 and year <= 1699)
      offset = 10
    # after 1700, 1 day is added for each century, except if the century year is exactly divisible by 400 (in which case no days are added).
    # Safe until 4100 AD, when one leap day will be removed.
    when year >= 1700
      offset = (year - 1700).divmod(100)[0] + ((year - year.divmod(100)[1]).divmod(400)[1] == 0 ? 0 : 1) - (year - year.divmod(100)[1] - 1700).divmod(400)[0] + 10
  end
  # add offset to the julian day
  return Date.jd(j_date.jd + offset)
end

.parse_definition_files_and_return_source(module_name, *files) ⇒ Object

Parses provided holiday definition file(s) and returns strings containing the generated module and test source



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# File 'lib/holidays.rb', line 334

def self.parse_definition_files_and_return_source(module_name, *files)
  regions, rules_by_month, custom_methods, tests = self.parse_definition_files(files)
  module_src, test_src = self.generate_definition_source(module_name, files, regions, rules_by_month, custom_methods, tests)

  return module_src, test_src
end

.ph_heroes_day(year) ⇒ Object

last Monday of August



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# File 'lib/holidays/ph.rb', line 42

def self.ph_heroes_day(year)
  date = Date.new(year, 8, -1)
  return date if date.wday == 1
  date -= date.wday - 1
end

.pl_trzech_kroli(year) ⇒ Object

Poland: January 6 is holiday since 2011



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# File 'lib/holidays/pl.rb', line 66

def self.pl_trzech_kroli(year)
  year >= 2011 ? 6 : nil
end

.pl_trzech_kroli_informal(year) ⇒ Object

Poland: January 6 wasn’t holiday before 2011



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# File 'lib/holidays/pl.rb', line 72

def self.pl_trzech_kroli_informal(year)
  year < 2011 ? 6 : nil
end

.previous_friday(date) ⇒ Object



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# File 'lib/holidays/nz.rb', line 61

def self.previous_friday(date)
  date - 3
end

.qld_labour_day_may(year) ⇒ Object



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# File 'lib/holidays/au.rb', line 64

def self.qld_labour_day_may(year)
  year <= 2012 ? Date.calculate_mday(year, 5, 1, 1) : nil
end

.qld_labour_day_october(year) ⇒ Object



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# File 'lib/holidays/au.rb', line 71

def self.qld_labour_day_october(year)
  year <= 2012 ? nil : Date.calculate_mday(year, 10, 1, 1)
end

.qld_queens_bday_october(year) ⇒ Object



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# File 'lib/holidays/au.rb', line 57

def self.qld_queens_bday_october(year)
  year == 2012 ? 1 : nil
end

.regionsObject

Returns an array of symbols of all the available holiday regions.



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# File 'lib/holidays.rb', line 318

def self.regions
  @@regions
end

.se_alla_helgons_dag(year) ⇒ Object

Sweden: All Saint’s Day (Saturday between Oct 31 and Nov 6)



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# File 'lib/holidays/se.rb', line 51

def self.se_alla_helgons_dag(year)
  date = Date.civil(year,10,31)
  date += (6 - date.wday)
  date
end

.se_midsommardagen(year) ⇒ Object

Sweden: Mid-summer (Saturday between June 20–26)



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# File 'lib/holidays/se.rb', line 43

def self.se_midsommardagen(year)
  date = Date.civil(year,6,20)
  date += (6 - date.wday)
  date
end

.to_monday_if_sunday(date) ⇒ Object

Move date to Monday if it occurs on a Sunday. Used as a callback function.



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# File 'lib/holidays.rb', line 276

def self.to_monday_if_sunday(date)
  date += 1 if date.wday == 0
  date
end

.to_monday_if_weekend(date) ⇒ Object

Move date to Monday if it occurs on a Saturday on Sunday. Used as a callback function.



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# File 'lib/holidays.rb', line 283

def self.to_monday_if_weekend(date)
  date += 1 if date.wday == 0
  date += 2 if date.wday == 6
  date
end

.to_weekday_if_boxing_weekend(date) ⇒ Object

Move Boxing Day if it falls on a weekend, leaving room for Christmas. Used as a callback function.



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# File 'lib/holidays.rb', line 291

def self.to_weekday_if_boxing_weekend(date)
  if date.wday == 6 or date.wday == 0
    date += 2
  elsif date.wday == 1
    date += 1
  end
  date
end

.to_weekday_if_weekend(date) ⇒ Object

Move date to Monday if it occurs on a Sunday or to Friday if it occurs on a Saturday. Used as a callback function.



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# File 'lib/holidays.rb', line 303

def self.to_weekday_if_weekend(date)
  date += 1 if date.wday == 0
  date -= 1 if date.wday == 6
  date
end

.us_inauguration_day(year) ⇒ Object

January 20, every fourth year, following Presidential election



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# File 'lib/holidays/us.rb', line 50

def self.us_inauguration_day(year)
  year % 4 == 1 ? 20 : nil
end