Introduce ObservedHolidays class (#1444)

Co-authored-by: Arkadii Yakovets <[email protected]>

holidays/countries/albania.py

@@ -9,21 +9,20 @@
 #  Website: https://github.com/dr-prodigy/python-holidays
 #  License: MIT (see LICENSE file)
 
-from datetime import timedelta as td
-
 from holidays.calendars.gregorian import MAR
 from holidays.calendars.julian import JULIAN_CALENDAR
-from holidays.groups import ChristianHolidays, IslamicHolidays, InternationalHolidays
-from holidays.holiday_base import HolidayBase
+from holidays.groups import ChristianHolidays, InternationalHolidays, IslamicHolidays
+from holidays.observed_holiday_base import ObservedHolidayBase, SAT_SUN_TO_NEXT_WORKDAY
 
 
-class Albania(HolidayBase, ChristianHolidays, InternationalHolidays, IslamicHolidays):
+class Albania(ObservedHolidayBase, ChristianHolidays, InternationalHolidays, IslamicHolidays):
     """
     References:
       - https://en.wikipedia.org/wiki/Public_holidays_in_Albania
     """
 
     country = "AL"
+    observed_label = "%s (Observed)"
     special_holidays = {
         2022: (MAR, 21, "Public Holiday"),
     }
@@ -32,70 +31,63 @@ def __init__(self, *args, **kwargs):
         ChristianHolidays.__init__(self)
         InternationalHolidays.__init__(self)
         IslamicHolidays.__init__(self)
-        super().__init__(*args, **kwargs)
+        super().__init__(observed_rule=SAT_SUN_TO_NEXT_WORKDAY, *args, **kwargs)
 
     def _populate(self, year):
         super()._populate(year)
-        observed_dates = set()
+        dts_observed = set()
 
         # New Year's Day.
         name = "New Year's Day"
-        observed_dates.add(self._add_new_years_day(name))
-        observed_dates.add(self._add_new_years_day_two(name))
+        dts_observed.add(self._add_new_years_day(name))
+        dts_observed.add(self._add_new_years_day_two(name))
 
         # Summer Day.
         if year >= 2004:
-            observed_dates.add(self._add_holiday_mar_14("Summer Day"))
+            dts_observed.add(self._add_holiday_mar_14("Summer Day"))
 
         # Nevruz.
         if year >= 1996:
-            observed_dates.add(self._add_holiday_mar_22("Nevruz"))
+            dts_observed.add(self._add_holiday_mar_22("Nevruz"))
 
         # Easter.
-        observed_dates.add(self._add_easter_sunday("Catholic Easter"))
-        observed_dates.add(self._add_easter_sunday("Orthodox Easter", JULIAN_CALENDAR))
+        dts_observed.add(self._add_easter_sunday("Catholic Easter"))
+        dts_observed.add(self._add_easter_sunday("Orthodox Easter", JULIAN_CALENDAR))
 
         # May Day.
-        observed_dates.add(self._add_labor_day("May Day"))
+        dts_observed.add(self._add_labor_day("May Day"))
 
         # Mother Teresa Day.
         if 2004 <= year <= 2017:
-            observed_dates.add(self._add_holiday_oct_19("Mother Teresa Beatification Day"))
+            dts_observed.add(self._add_holiday_oct_19("Mother Teresa Beatification Day"))
         elif year >= 2018:
-            observed_dates.add(self._add_holiday_sep_5("Mother Teresa Canonization Day"))
+            dts_observed.add(self._add_holiday_sep_5("Mother Teresa Canonization Day"))
 
         # Independence Day.
-        observed_dates.add(self._add_holiday_nov_28("Independence Day"))
+        dts_observed.add(self._add_holiday_nov_28("Independence Day"))
 
         # Liberation Day.
-        observed_dates.add(self._add_holiday_nov_29("Liberation Day"))
+        dts_observed.add(self._add_holiday_nov_29("Liberation Day"))
 
         # National Youth Day.
         if year >= 2009:
-            observed_dates.add(self._add_holiday_dec_8("National Youth Day"))
+            dts_observed.add(self._add_holiday_dec_8("National Youth Day"))
 
         # Christmas Day.
-        observed_dates.add(self._add_christmas_day("Christmas Day"))
+        dts_observed.add(self._add_christmas_day("Christmas Day"))
 
         # Eid al-Fitr.
-        observed_dates.update(self._add_eid_al_fitr_day("Eid al-Fitr"))
+        dts_observed.update(self._add_eid_al_fitr_day("Eid al-Fitr"))
 
         # Eid al-Adha.
-        observed_dates.update(self._add_eid_al_adha_day("Eid al-Adha"))
+        dts_observed.update(self._add_eid_al_adha_day("Eid al-Adha"))
 
         if self.observed:
-            for dt in sorted(observed_dates):
-                if not self._is_weekend(dt):
-                    continue
-                dt_observed = dt + td(days=+1)
-                while self._is_weekend(dt_observed) or dt_observed in observed_dates:
-                    dt_observed += td(days=+1)
-                for name in self.get_list(dt):
-                    observed_dates.add(self._add_holiday("%s (Observed)" % name, dt_observed))
-
-            # observed holidays special cases
+            self._populate_observed(dts_observed)
+
+            # Observed holidays special cases.
             if year == 2007:
-                self._add_holiday_jan_3("Eid al-Adha (Observed)")
+                self._add_holiday_jan_3(self.observed_label % "Eid al-Adha")
 
 
 class AL(Albania):

holidays/countries/angola.py

@@ -10,15 +10,20 @@
 #  License: MIT (see LICENSE file)
 
 from datetime import date
-from datetime import timedelta as td
 from gettext import gettext as tr
+from typing import Tuple
 
 from holidays.calendars.gregorian import AUG, SEP, DEC
 from holidays.groups import ChristianHolidays, InternationalHolidays
-from holidays.holiday_base import HolidayBase
+from holidays.observed_holiday_base import (
+    ObservedHolidayBase,
+    TUE_TO_PREV_MON,
+    THU_TO_NEXT_FRI,
+    SUN_TO_NEXT_MON,
+)
 
 
-class Angola(HolidayBase, ChristianHolidays, InternationalHolidays):
+class Angola(ObservedHolidayBase, ChristianHolidays, InternationalHolidays):
     """
     References:
     - https://en.wikipedia.org/wiki/Public_holidays_in_Angola
@@ -38,6 +43,8 @@ class Angola(HolidayBase, ChristianHolidays, InternationalHolidays):
     country = "AO"
     default_language = "pt_AO"
     supported_languages = ("en_US", "pt_AO", "uk")
+    # %s (Observed).
+    observed_label = tr("%s (Ponte)")
     special_holidays = {
         # General Election Day.
         2017: (AUG, 23, tr("Dia de eleições gerais")),
@@ -46,23 +53,19 @@ class Angola(HolidayBase, ChristianHolidays, InternationalHolidays):
     def __init__(self, *args, **kwargs):
         ChristianHolidays.__init__(self)
         InternationalHolidays.__init__(self)
-        super().__init__(*args, **kwargs)
+        super().__init__(observed_rule=TUE_TO_PREV_MON + THU_TO_NEXT_FRI, *args, **kwargs)
 
-    def _add_observed(self, dt: date) -> None:
-        if not self.observed:
-            return None
-        # As per Law # #11/18, from 2018/9/10, when public holiday falls on Tuesday or Thursday,
-        # the Monday or Friday is also a holiday.
-        if dt >= date(2018, SEP, 10):
-            if self._is_tuesday(dt):
-                # Day off for %s.
-                self._add_holiday(self.tr("%s (Ponte)") % self[dt], dt + td(days=-1))
-            elif self._is_thursday(dt):
-                self._add_holiday(self.tr("%s (Ponte)") % self[dt], dt + td(days=+1))
+    def _is_observed(self, dt: date) -> bool:
         # As per Law # 16/96, from 1996/9/27, when public holiday falls on Sunday,
         # it rolls over to the following Monday.
-        elif dt >= date(1996, SEP, 27) and self._is_sunday(dt):
-            self._add_holiday(self.tr("%s (Ponte)") % self[dt], dt + td(days=+1))
+        return dt >= date(1996, SEP, 27)
+
+    def _add_observed(self, dt: date, *args) -> Tuple[bool, date]:
+        # As per Law # #11/18, from 2018/9/10, when public holiday falls on Tuesday or Thursday,
+        # the Monday or Friday is also a holiday.
+        return super()._add_observed(
+            dt, rule=SUN_TO_NEXT_MON if dt < date(2018, SEP, 10) else self._observed_rule
+        )
 
     def _populate(self, year):
         # Decree #5/75.
@@ -78,7 +81,7 @@ def _populate(self, year):
             self._add_observed(dt)
 
         if self.observed and self._is_monday(DEC, 31) and year >= 2018:
-            self._add_holiday(self.tr("%s (Ponte)") % name, DEC, 31)
+            self._add_holiday_dec_31(self.tr(self.observed_label) % name)
 
         # Law #16/96.
         if 1997 <= year <= 2011:

holidays/countries/argentina.py

@@ -9,30 +9,19 @@
 #  Website: https://github.com/dr-prodigy/python-holidays
 #  License: MIT (see LICENSE file)
 
-from datetime import date
 from gettext import gettext as tr
 
-from holidays.calendars.gregorian import (
-    JAN,
-    FEB,
-    MAR,
-    APR,
-    MAY,
-    JUN,
-    JUL,
-    AUG,
-    SEP,
-    OCT,
-    NOV,
-    DEC,
-    MON,
-    _get_nth_weekday_from,
-)
+from holidays.calendars.gregorian import JAN, FEB, MAR, APR, MAY, JUN, JUL, AUG, SEP, OCT, NOV, DEC
 from holidays.groups import ChristianHolidays, InternationalHolidays
-from holidays.holiday_base import HolidayBase
+from holidays.observed_holiday_base import (
+    ObservedHolidayBase,
+    THU_TO_NEXT_MON,
+    TUE_WED_TO_PREV_MON,
+    THU_FRI_TO_NEXT_MON,
+)
 
 
-class Argentina(HolidayBase, ChristianHolidays, InternationalHolidays):
+class Argentina(ObservedHolidayBase, ChristianHolidays, InternationalHolidays):
     """
     A subclass of :py:class:`HolidayBase` representing public holidays
     in Argentina.
@@ -69,11 +58,20 @@ class Argentina(HolidayBase, ChristianHolidays, InternationalHolidays):
         https://servicios.lanacion.com.ar/app-mobile/feriados/2017
         https://servicios.lanacion.com.ar/app-mobile/feriados/2016
         https://servicios.lanacion.com.ar/app-mobile/feriados/2015
+
+        Movable Holidays Laws:
+    - Decreto 1584/2010: 2010-11-03
+        - AUG 17, OCT 12, NOV 20 Holidays will always be on MON
+    - Decreto 52/2017: 2017-01-23 (Reconfirmed in Ley 27399)
+        - If TUE/WED - observed on previous MON
+        - If THU/FRI - observed on next MON
     """
 
     country = "AR"
     default_language = "es"
     supported_languages = ("en_US", "es", "uk")
+    # %s (Observed).
+    observed_label = tr("%s (Observado)")
 
     # Special Bridge Holidays are given upto 3 days a year
     # as long as it's declared 50 days before calendar year's end
@@ -166,27 +164,7 @@ class Argentina(HolidayBase, ChristianHolidays, InternationalHolidays):
     def __init__(self, *args, **kwargs):
         ChristianHolidays.__init__(self)
         InternationalHolidays.__init__(self)
-        super().__init__(*args, **kwargs)
-
-    def _move_holiday(self, dt: date) -> None:
-        """
-         Movable Holidays Laws:
-        - Decreto 1584/2010: 2010-11-03
-            - AUG 17, OCT 12, NOV 20 Holidays will always be on MON
-        - Decreto 52/2017: 2017-01-23 (Reconfirmed in Ley 27399)
-            - If TUE/WED - observed on previous MON
-            - If THU/FRI - observed on next MON
-        """
-        if self.observed:
-            dt_observed = None
-            if self._is_tuesday(dt) or self._is_wednesday(dt):
-                dt_observed = _get_nth_weekday_from(-1, MON, dt)
-            elif self._is_thursday(dt) or self._is_friday(dt):
-                dt_observed = _get_nth_weekday_from(+1, MON, dt)
-
-            if dt_observed:
-                self._add_holiday(self.tr("%s (Observado)") % self[dt], dt_observed)
-                self.pop(dt)
+        super().__init__(observed_rule=TUE_WED_TO_PREV_MON + THU_FRI_TO_NEXT_MON, *args, **kwargs)
 
     def _populate(self, year):
         super()._populate(year)
@@ -301,8 +279,7 @@ def _populate(self, year):
             )
             # If Jun 17 is Friday, then it should move to Mon, Jun 20
             # but Jun 20 is Gen. Belgrano holiday
-            if not self._is_friday(jun_17):
-                self._move_holiday(jun_17)
+            self._move_holiday(jun_17, rule=TUE_WED_TO_PREV_MON + THU_TO_NEXT_MON)
 
         # Status: In-Use.
         # Started in 1938 via Ley 12387 on Aug 17.

holidays/countries/australia.py

@@ -14,16 +14,22 @@
 
 from holidays.calendars.gregorian import APR, AUG, SEP, OCT, FRI, _get_nth_weekday_from
 from holidays.groups import ChristianHolidays, InternationalHolidays
-from holidays.holiday_base import HolidayBase
+from holidays.observed_holiday_base import (
+    ObservedHolidayBase,
+    SUN_TO_NEXT_MON,
+    SAT_SUN_TO_NEXT_MON,
+    SAT_SUN_TO_NEXT_MON_TUE,
+)
 
 
-class Australia(HolidayBase, ChristianHolidays, InternationalHolidays):
+class Australia(ObservedHolidayBase, ChristianHolidays, InternationalHolidays):
     """
     References:
       - https://www.qld.gov.au/recreation/travel/holidays
     """
 
     country = "AU"
+    observed_label = "%s (Observed)"
     special_holidays = {
         2022: (SEP, 22, "National Day of Mourning for Queen Elizabeth II"),
     }
@@ -41,15 +47,7 @@ def sovereign_birthday(self) -> str:
     def __init__(self, *args, **kwargs):
         ChristianHolidays.__init__(self)
         InternationalHolidays.__init__(self)
-        super().__init__(*args, **kwargs)
-
-    def _add_observed(self, dt: date, include_sat: bool = True, days: int = +1) -> None:
-        if not self.observed:
-            return None
-        if self._is_sunday(dt) or (include_sat and self._is_saturday(dt)):
-            self._add_holiday(
-                "%s (Observed)" % self[dt], dt + td(days=+2 if self._is_saturday(dt) else days)
-            )
+        super().__init__(observed_rule=SAT_SUN_TO_NEXT_MON, *args, **kwargs)
 
     def _populate(self, year):
         super()._populate(year)
@@ -98,11 +96,11 @@ def _add_subdiv_holidays(self):
             self._add_holiday_apr_25("Anzac Day")
 
         # Christmas Day
-        self._add_observed(self._add_christmas_day("Christmas Day"), days=+2)
+        self._add_observed(self._add_christmas_day("Christmas Day"), rule=SAT_SUN_TO_NEXT_MON_TUE)
 
         # Boxing Day
         name = "Proclamation Day" if self.subdiv == "SA" else "Boxing Day"
-        self._add_observed(self._add_christmas_day_two(name), days=+2)
+        self._add_observed(self._add_christmas_day_two(name), rule=SAT_SUN_TO_NEXT_MON_TUE)
 
         super()._add_subdiv_holidays()
 
@@ -120,7 +118,7 @@ def _add_subdiv_act_holidays(self):
 
         # Anzac Day
         if self._year >= 1921:
-            self._add_observed(date(self._year, APR, 25), include_sat=False)
+            self._add_observed(date(self._year, APR, 25), rule=SUN_TO_NEXT_MON)
 
         # Canberra Day
         # Info from https://www.timeanddate.com/holidays/australia/canberra-day
@@ -217,15 +215,15 @@ def _add_subdiv_qld_holidays(self):
 
         # Anzac Day
         if self._year >= 1921:
-            self._add_observed(date(self._year, APR, 25), include_sat=False)
+            self._add_observed((APR, 25), rule=SUN_TO_NEXT_MON)
 
         # The Royal Queensland Show (Ekka)
         # The Show starts on the first Friday of August - providing this is
         # not prior to the 5th - in which case it will begin on the second
         # Friday. The Wednesday during the show is a public holiday.
         ekka_dates = {
-            2020: date(2020, AUG, 14),
-            2021: date(2021, OCT, 29),
+            2020: (AUG, 14),
+            2021: (OCT, 29),
         }
         name = "The Royal Queensland Show"
         if self._year in ekka_dates:
@@ -248,7 +246,7 @@ def _add_subdiv_sa_holidays(self):
 
         # Anzac Day
         if self._year >= 1921:
-            self._add_observed(date(self._year, APR, 25), include_sat=False)
+            self._add_observed((APR, 25), rule=SUN_TO_NEXT_MON)
 
         # Adelaide Cup
         name = "Adelaide Cup"