Learnt from: PPsyrius
PR: vacanza/holidays#2632
File: holidays/countries/solomon_islands.py:95-98
Timestamp: 2025-06-16T12:28:31.641Z
Learning: Library-wide holiday patterns and their optimizations should be handled at the base class level (like InternationalHolidays) rather than documenting workarounds in individual country modules. This maintains separation of concerns and avoids documentation duplication.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: PPsyrius
PR: vacanza/holidays#2323
File: holidays/countries/macau.py:407-461
Timestamp: 2025-03-04T11:32:45.095Z
Learning: In the holidays library, the standard approach for organizing static holidays is to use separate dictionaries for different categories (`government`, `mandatory`, and `public`), which are utilized by syntactic sugar methods.

Learnt from: PPsyrius
PR: vacanza/holidays#2323
File: holidays/countries/macau.py:407-461
Timestamp: 2025-03-04T11:32:45.095Z
Learning: In the holidays library, the standard approach for organizing static holidays is to use separate dictionaries for different categories (like `special_government_holidays`, `special_mandatory_holidays`, and `special_public_holidays`), which are utilized by syntactic sugar methods to pick up the appropriate holidays based on the selected category.

Learnt from: PPsyrius
PR: vacanza/holidays#2323
File: holidays/countries/macau.py:407-461
Timestamp: 2025-03-04T11:32:45.095Z
Learning: In the holidays library, the standard approach for organizing static holidays is to use separate dictionaries for different categories (like `special_government_holidays`, `special_mandatory_holidays`, and `special_public_holidays`), which are utilized by syntactic sugar methods to pick up the appropriate holidays based on the selected category.

Learnt from: PPsyrius
PR: vacanza/holidays#2642
File: holidays/countries/saint_pierre_and_miquelon.py:39-48
Timestamp: 2025-06-18T15:34:18.326Z
Learning: The holidays library does not use `__all__` declarations in country modules. Country files follow a standard pattern without explicit exports, and suggesting `__all__` goes against the established library-wide convention.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: KJhellico
PR: vacanza/holidays#2593
File: holidays/countries/senegal.py:66-110
Timestamp: 2025-06-06T14:40:31.932Z
Learning: In the holidays library, within the _populate_public_holidays method, holidays should be arranged by calendar type (Islamic holidays first, then Gregorian holidays) without additional type grouping comments. The organization by calendar type is sufficient and follows the project's established conventions.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2490
File: holidays/countries/ethiopia.py:45-45
Timestamp: 2025-04-23T09:59:19.886Z
Learning: For the Ethiopia holidays class, it's appropriate to add a return type hint only to the `_is_leap_year` method to match the base class implementation in `holidays/holiday_base.py`, while keeping other methods without type hints to maintain consistency with other country implementations.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:21:59.302Z
Learning: In the Saint Vincent and the Grenadines holiday tests, for holidays without observed rules that only require a single assertHolidayName call, pass the holiday name directly as a string literal rather than storing it in a variable first for cleaner, more concise code.

Learnt from: PPsyrius
PR: vacanza/holidays#2632
File: holidays/countries/solomon_islands.py:95-98
Timestamp: 2025-06-16T12:28:31.641Z
Learning: Library-wide holiday patterns and their optimizations should be handled at the base class level (like InternationalHolidays) rather than documenting workarounds in individual country modules. This maintains separation of concerns and avoids documentation duplication.

Learnt from: PPsyrius
PR: vacanza/holidays#2642
File: holidays/countries/france.py:300-319
Timestamp: 2025-06-18T10:21:01.376Z
Learning: In the France holidays implementation, legislative years for holiday changes should be hard-coded rather than extracted into constants, as this maintains consistency with the existing codebase pattern and provides historical accuracy for specific legislative acts.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:52-64
Timestamp: 2025-04-05T04:47:27.213Z
Learning: For holiday tests in the vacanza/holidays project, structure tests by individual holidays rather than by years. Each test method should focus on a specific holiday and test it across multiple years (from start_year through 2050) using helper methods like `assertHolidayName`. For fixed holidays, use generators like `(f"{year}-01-01" for year in range(1991, 2051))`. For movable holidays, specify individual dates for specific years followed by a range check.

Learnt from: KJhellico
PR: vacanza/holidays#2593
File: holidays/countries/senegal.py:66-110
Timestamp: 2025-06-06T14:40:31.932Z
Learning: In the holidays library, within the _populate_public_holidays method, holidays should be arranged by calendar type (Islamic holidays first, then Gregorian holidays) without additional type grouping comments. The organization by calendar type is sufficient and follows the project's established conventions.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: KJhellico
PR: vacanza/holidays#2635
File: holidays/countries/bhutan.py:13-16
Timestamp: 2025-06-16T14:08:09.492Z
Learning: In the holidays library, translation is performed in the `_add_holiday` methods, not at the string level. Holiday strings passed to `_add_holiday_*` methods are processed through the translation machinery within those methods, so using `tr()` or `self.tr()` wrappers is unnecessary.

Learnt from: KJhellico
PR: vacanza/holidays#2606
File: holidays/countries/faroe_islands.py:62-67
Timestamp: 2025-06-15T15:24:53.055Z
Learning: The `HolidayBase` class uses `__getattr__` to dynamically implement `_add_holiday_*` methods through pattern matching, including patterns like `_add_holiday_<n>_days_past_easter`, `_add_holiday_<month>_<day>`, and various weekday-relative patterns. Methods like `_add_holiday_26_days_past_easter` are not explicitly defined but are dynamically generated when called.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: holidays/countries/mongolia.py:140-146
Timestamp: 2025-06-15T11:50:44.366Z
Learning: The holidays library doesn't currently have helper functions like `_add_holiday_span` for adding consecutive multi-day holidays. Countries like Mongolia, Thailand, and Vietnam implement multi-day holiday spans using inline loops with `_timedelta(dt, delta)` pattern.

Learnt from: KJhellico
PR: vacanza/holidays#2631
File: holidays/countries/sint_maarten.py:94-95
Timestamp: 2025-06-14T20:43:15.370Z
Learning: The `_add_*` helper methods in the holidays library (such as `_add_christmas_day_two()`, `_add_labor_day()`, etc.) don't have default holiday names, so the name parameter should always be explicitly specified when calling these methods.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:21:59.302Z
Learning: In the Saint Vincent and the Grenadines holiday tests, for holidays without observed rules that only require a single assertHolidayName call, pass the holiday name directly as a string literal rather than storing it in a variable first for cleaner, more concise code.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2632
File: holidays/countries/solomon_islands.py:95-98
Timestamp: 2025-06-16T12:28:31.641Z
Learning: Library-wide holiday patterns and their optimizations should be handled at the base class level (like InternationalHolidays) rather than documenting workarounds in individual country modules. This maintains separation of concerns and avoids documentation duplication.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: tests/countries/test_mongolia.py:128-156
Timestamp: 2025-06-15T11:52:39.572Z
Learning: In the vacanza/holidays project tests, when testing holidays that span multiple consecutive days across many years (like Mongolia's National Festival spanning July 11-13), prefer explicit for loops over complex nested generator expressions with unpacking. The explicit loops are more readable, easier to maintain, and better communicate the testing intent even though the Big O complexity is equivalent.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:22-26
Timestamp: 2025-04-23T14:55:35.504Z
Learning: References in holidays classes should only be included if they're used for test case cross-checks or provide historical context about when holidays were added/removed, not just for the sake of having more references.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:22-26
Timestamp: 2025-04-23T14:55:35.504Z
Learning: References in holidays classes should only be included if they're used for test case cross-checks or provide historical context about when holidays were added/removed, not just for the sake of having more references.

Learnt from: KJhellico
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:171-183
Timestamp: 2025-03-29T15:15:05.919Z
Learning: In the Fiji holidays implementation, the maintainers are aware of the need to extend the MAWLID_DATES dictionary beyond 2025 when future official references become available, and will do so when appropriate. No suggestions about extending this dictionary should be made in future reviews.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2635
File: holidays/countries/bhutan.py:13-16
Timestamp: 2025-06-16T14:08:09.492Z
Learning: In the holidays library, translation is performed in the `_add_holiday` methods, not at the string level. Holiday strings passed to `_add_holiday_*` methods are processed through the translation machinery within those methods, so using `tr()` or `self.tr()` wrappers is unnecessary.

Learnt from: KJhellico
PR: vacanza/holidays#2631
File: holidays/countries/sint_maarten.py:94-95
Timestamp: 2025-06-14T20:43:15.370Z
Learning: The `_add_*` helper methods in the holidays library (such as `_add_christmas_day_two()`, `_add_labor_day()`, etc.) don't have default holiday names, so the name parameter should always be explicitly specified when calling these methods.

Learnt from: KJhellico
PR: vacanza/holidays#2606
File: holidays/countries/faroe_islands.py:62-67
Timestamp: 2025-06-15T15:24:53.055Z
Learning: The `HolidayBase` class uses `__getattr__` to dynamically implement `_add_holiday_*` methods through pattern matching, including patterns like `_add_holiday_<n>_days_past_easter`, `_add_holiday_<month>_<day>`, and various weekday-relative patterns. Methods like `_add_holiday_26_days_past_easter` are not explicitly defined but are dynamically generated when called.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:48-50
Timestamp: 2025-06-14T11:05:21.250Z
Learning: In the holidays library, newer implementations use `start_year` to indicate the earliest year with complete holiday data coverage, not necessarily the first year a holiday existed. If a holiday system starts partway through a year (like Nauru's Public Holidays Act starting Jan 31, 1968), the start_year should be set to the following year (1969) to ensure users get full annual holiday coverage.

Learnt from: KJhellico
PR: vacanza/holidays#2483
File: holidays/countries/turks_and_caicos_islands.py:117-118
Timestamp: 2025-05-13T13:23:11.375Z
Learning: The holidays library uses `_add_christmas_day_two` method to add Boxing Day holiday, not `_add_boxing_day`.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:21:59.302Z
Learning: In the Saint Vincent and the Grenadines holiday tests, for holidays without observed rules that only require a single assertHolidayName call, pass the holiday name directly as a string literal rather than storing it in a variable first for cleaner, more concise code.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: KJhellico
PR: vacanza/holidays#2483
File: holidays/registry.py:177-177
Timestamp: 2025-04-18T21:13:55.589Z
Learning: In the holidays/registry.py file, COUNTRIES dictionary entries should use the class name (without spaces) as the first element of the tuple (e.g., "TurksAndCaicosIslands"), not the human-readable country name with spaces.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2643
File: holidays/countries/mauritius.py:171-184
Timestamp: 2025-06-19T02:34:14.456Z
Learning: In the holidays library, `_CustomIslamicHolidays` subclasses follow a consistent pattern of NOT having docstrings. They go directly to defining date dictionaries, as evidenced by Malaysia, Singapore, UAE, and dozens of other country implementations.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:22-26
Timestamp: 2025-04-23T14:55:35.504Z
Learning: References in holidays classes should only be included if they're used for test case cross-checks or provide historical context about when holidays were added/removed, not just for the sake of having more references.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:22-26
Timestamp: 2025-04-23T14:55:35.504Z
Learning: References in holidays classes should only be included if they're used for test case cross-checks or provide historical context about when holidays were added/removed, not just for the sake of having more references.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2631
File: holidays/countries/sint_maarten.py:94-95
Timestamp: 2025-06-14T20:43:15.370Z
Learning: The `_add_*` helper methods in the holidays library (such as `_add_christmas_day_two()`, `_add_labor_day()`, etc.) don't have default holiday names, so the name parameter should always be explicitly specified when calling these methods.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: holidays/countries/mongolia.py:140-146
Timestamp: 2025-06-15T11:50:44.366Z
Learning: The holidays library doesn't currently have helper functions like `_add_holiday_span` for adding consecutive multi-day holidays. Countries like Mongolia, Thailand, and Vietnam implement multi-day holiday spans using inline loops with `_timedelta(dt, delta)` pattern.

Learnt from: KJhellico
PR: vacanza/holidays#2483
File: holidays/countries/turks_and_caicos_islands.py:117-118
Timestamp: 2025-05-13T13:23:11.375Z
Learning: The holidays library uses `_add_christmas_day_two` method to add Boxing Day holiday, not `_add_boxing_day`.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2593
File: holidays/calendars/islamic.py:3993-3994
Timestamp: 2025-06-04T10:09:28.732Z
Learning: In the holidays/calendars/islamic.py file, the Islamic calendar date methods in the _IslamicLunar class (like ali_al_rida_death_dates, ashura_dates, etc.) follow a consistent pattern of being single-line methods that return self._get_holiday(CONSTANT, year) without docstrings. New methods should follow this same pattern for consistency.

Learnt from: PPsyrius
PR: vacanza/holidays#2388
File: holidays/countries/ivory_coast.py:84-85
Timestamp: 2025-03-30T08:08:30.415Z
Learning: Islamic holiday logic should be implemented in the holidays/groups/islamic.py file, with country-specific files only calling these methods with the appropriate translated names.

Learnt from: PPsyrius
PR: vacanza/holidays#2388
File: holidays/countries/ivory_coast.py:84-85
Timestamp: 2025-03-30T08:08:31.656Z
Learning: Islamic holiday logic should be implemented in the holidays/groups/islamic.py file, with country-specific files only calling these methods with the appropriate translated names.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: KJhellico
PR: vacanza/holidays#2593
File: holidays/countries/senegal.py:66-110
Timestamp: 2025-06-06T14:40:31.932Z
Learning: In the holidays library, within the _populate_public_holidays method, holidays should be arranged by calendar type (Islamic holidays first, then Gregorian holidays) without additional type grouping comments. The organization by calendar type is sufficient and follows the project's established conventions.

Learnt from: KJhellico
PR: vacanza/holidays#2671
File: holidays/countries/libya.py:51-108
Timestamp: 2025-06-29T10:36:06.138Z
Learning: There is no project-wide convention in the holidays library to organize holidays by calendar type (Islamic holidays first, then Gregorian holidays). Countries organize holidays in various ways - often chronologically, by importance, or by logical grouping - and Islamic holidays are frequently placed at the end of the _populate_public_holidays method rather than at the beginning.

Learnt from: KJhellico
PR: vacanza/holidays#2465
File: holidays/countries/suriname.py:219-251
Timestamp: 2025-04-13T19:10:31.502Z
Learning: The `_CustomIslamicHolidays` classes in this project contain only exact verified holiday dates from reliable sources, rather than calculated or estimated future dates. This is by design to ensure accuracy, particularly for religious holidays that may follow lunar calendars or depend on local observations.

Learnt from: KJhellico
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:101-106
Timestamp: 2025-04-03T13:03:16.558Z
Learning: For Islamic holidays in Guinea like "Lendemain de la nuit Lailatoul Qadr" (Day after Night of Power) and "Lendemain de la nuit du Maoloud" (Day after Prophet's Birthday), the naming refers to the daylight hours following the night when these Islamic observances occur. Since in the Islamic calendar days begin at sunset rather than midnight, methods like `_add_laylat_al_qadr_day` and `_add_mawlid_day` correctly calculate these dates without requiring an additional day offset in the implementation, following the same pattern as in the Ivory Coast implementation.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2522
File: holidays/countries/yemen.py:158-163
Timestamp: 2025-05-06T13:01:22.693Z
Learning: In the holidays library, the RAMADAN_BEGINNING_DATES dictionary in country-specific Islamic holiday classes (like YemenIslamicHolidays) is used indirectly through the backend. When a country class calls _add_holiday_29_ramadan(), the IslamicHolidays implementation uses the country's custom calendar dates to calculate the 29th day of Ramadan by adding 28 days to the beginning date.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:266-284
Timestamp: 2025-04-13T20:41:56.613Z
Learning: The Islamic holiday dates in the holidays library should only include officially verified dates, not predicted ones, to maintain accuracy. This is especially important for holidays that depend on lunar observations like Eid al-Fitr and Eid al-Adha.

Learnt from: KJhellico
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:101-106
Timestamp: 2025-04-03T13:03:16.558Z
Learning: For Islamic holidays in Guinea like "Lendemain de la nuit Lailatoul Qadr" (Day after Night of Power) and "Lendemain de la nuit du Maoloud" (Day after Prophet's Birthday), the naming refers to the daylight hours following the night when these Islamic observances occur. Since in the Islamic calendar days begin at sunset rather than midnight, methods like `_add_laylat_al_qadr_day` and `_add_mawlid_day` correctly calculate these dates without requiring an additional day offset in the implementation.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: PPsyrius
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:73-77
Timestamp: 2025-04-03T12:36:41.201Z
Learning: In the Holidays library, comments explaining year restrictions for holidays should be placed above the year check conditional statement, not inside it. Example format:
```python
# reason why goes here
if start_year <= self._year <= end_year:
    # Holiday name
    self._add_holiday_function(tr("Holiday Name"))
```

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:21:59.302Z
Learning: In the Saint Vincent and the Grenadines holiday tests, for holidays without observed rules that only require a single assertHolidayName call, pass the holiday name directly as a string literal rather than storing it in a variable first for cleaner, more concise code.

Learnt from: KJhellico
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:171-183
Timestamp: 2025-03-29T15:15:05.919Z
Learning: In the Fiji holidays implementation, the maintainers are aware of the need to extend the MAWLID_DATES dictionary beyond 2025 when future official references become available, and will do so when appropriate. No suggestions about extending this dictionary should be made in future reviews.

Learnt from: PPsyrius
PR: vacanza/holidays#2490
File: holidays/countries/ethiopia.py:45-45
Timestamp: 2025-04-23T09:59:19.886Z
Learning: For the Ethiopia holidays class, it's appropriate to add a return type hint only to the `_is_leap_year` method to match the base class implementation in `holidays/holiday_base.py`, while keeping other methods without type hints to maintain consistency with other country implementations.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:48-50
Timestamp: 2025-06-14T11:05:21.250Z
Learning: In the holidays library, newer implementations use `start_year` to indicate the earliest year with complete holiday data coverage, not necessarily the first year a holiday existed. If a holiday system starts partway through a year (like Nauru's Public Holidays Act starting Jan 31, 1968), the start_year should be set to the following year (1969) to ensure users get full annual holiday coverage.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: KJhellico
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:106-110
Timestamp: 2025-04-04T10:52:41.546Z
Learning: In the Guinea holidays implementation, observed Eid al-Fitr cases are properly covered by the test_eid_al_fitr_day() method, which tests both the regular holiday dates and the observed dates when the holiday falls on a non-working day (for years >= 2023).

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2642
File: holidays/countries/france.py:300-319
Timestamp: 2025-06-18T10:21:01.376Z
Learning: In the France holidays implementation, legislative years for holiday changes should be hard-coded rather than extracted into constants, as this maintains consistency with the existing codebase pattern and provides historical accuracy for specific legislative acts.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:21:59.302Z
Learning: In the Saint Vincent and the Grenadines holiday tests, for holidays without observed rules that only require a single assertHolidayName call, pass the holiday name directly as a string literal rather than storing it in a variable first for cleaner, more concise code.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: PPsyrius
PR: vacanza/holidays#2323
File: holidays/countries/macau.py:407-461
Timestamp: 2025-03-04T11:32:45.095Z
Learning: In the holidays library, the standard approach for organizing static holidays is to use separate dictionaries for different categories (`government`, `mandatory`, and `public`), which are utilized by syntactic sugar methods.

Learnt from: KJhellico
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:106-110
Timestamp: 2025-04-04T10:52:41.546Z
Learning: In the Guinea holidays implementation, observed Eid al-Fitr cases are properly covered by the test_eid_al_fitr_day() method, which tests both the regular holiday dates and the observed dates when the holiday falls on a non-working day (for years >= 2023).

Learnt from: PPsyrius
PR: vacanza/holidays#2632
File: holidays/countries/solomon_islands.py:95-98
Timestamp: 2025-06-16T12:28:31.641Z
Learning: Library-wide holiday patterns and their optimizations should be handled at the base class level (like InternationalHolidays) rather than documenting workarounds in individual country modules. This maintains separation of concerns and avoids documentation duplication.

Learnt from: KJhellico
PR: vacanza/holidays#2606
File: holidays/countries/faroe_islands.py:62-67
Timestamp: 2025-06-15T15:24:53.055Z
Learning: The `HolidayBase` class uses `__getattr__` to dynamically implement `_add_holiday_*` methods through pattern matching, including patterns like `_add_holiday_<n>_days_past_easter`, `_add_holiday_<month>_<day>`, and various weekday-relative patterns. Methods like `_add_holiday_26_days_past_easter` are not explicitly defined but are dynamically generated when called.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: holidays/countries/mongolia.py:140-146
Timestamp: 2025-06-15T11:50:44.366Z
Learning: The holidays library doesn't currently have helper functions like `_add_holiday_span` for adding consecutive multi-day holidays. Countries like Mongolia, Thailand, and Vietnam implement multi-day holiday spans using inline loops with `_timedelta(dt, delta)` pattern.

Learnt from: KJhellico
PR: vacanza/holidays#2631
File: holidays/countries/sint_maarten.py:94-95
Timestamp: 2025-06-14T20:43:15.370Z
Learning: The `_add_*` helper methods in the holidays library (such as `_add_christmas_day_two()`, `_add_labor_day()`, etc.) don't have default holiday names, so the name parameter should always be explicitly specified when calling these methods.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: KJhellico
PR: vacanza/holidays#2483
File: holidays/countries/turks_and_caicos_islands.py:117-118
Timestamp: 2025-05-13T13:23:11.375Z
Learning: The holidays library uses `_add_christmas_day_two` method to add Boxing Day holiday, not `_add_boxing_day`.

Learnt from: PPsyrius
PR: vacanza/holidays#2615
File: tests/countries/test_anguilla.py:52-64
Timestamp: 2025-06-15T10:15:39.883Z
Learning: In the Anguilla holidays implementation, March 2 only has "James Ronald Webster Day" (from 2010 onwards). There is no "Sovereignty Day" holiday on this date. Queen's/King's Birthday holidays are in June, not March.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: PPsyrius
PR: vacanza/holidays#2642
File: holidays/countries/france.py:300-319
Timestamp: 2025-06-18T10:21:01.376Z
Learning: In the France holidays implementation, legislative years for holiday changes should be hard-coded rather than extracted into constants, as this maintains consistency with the existing codebase pattern and provides historical accuracy for specific legislative acts.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:21:59.302Z
Learning: In the Saint Vincent and the Grenadines holiday tests, for holidays without observed rules that only require a single assertHolidayName call, pass the holiday name directly as a string literal rather than storing it in a variable first for cleaner, more concise code.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:22-26
Timestamp: 2025-04-23T14:55:35.504Z
Learning: References in holidays classes should only be included if they're used for test case cross-checks or provide historical context about when holidays were added/removed, not just for the sake of having more references.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:22-26
Timestamp: 2025-04-23T14:55:35.504Z
Learning: References in holidays classes should only be included if they're used for test case cross-checks or provide historical context about when holidays were added/removed, not just for the sake of having more references.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:52-64
Timestamp: 2025-04-05T04:47:27.213Z
Learning: For holiday tests in the vacanza/holidays project, structure tests by individual holidays rather than by years. Each test method should focus on a specific holiday and test it across multiple years (from start_year through 2050) using helper methods like `assertHolidayName`. For fixed holidays, use generators like `(f"{year}-01-01" for year in range(1991, 2051))`. For movable holidays, specify individual dates for specific years followed by a range check.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: holidays/countries/mongolia.py:140-146
Timestamp: 2025-06-15T11:50:44.366Z
Learning: The holidays library doesn't currently have helper functions like `_add_holiday_span` for adding consecutive multi-day holidays. Countries like Mongolia, Thailand, and Vietnam implement multi-day holiday spans using inline loops with `_timedelta(dt, delta)` pattern.

Learnt from: KJhellico
PR: vacanza/holidays#2606
File: holidays/countries/faroe_islands.py:62-67
Timestamp: 2025-06-15T15:24:53.055Z
Learning: The `HolidayBase` class uses `__getattr__` to dynamically implement `_add_holiday_*` methods through pattern matching, including patterns like `_add_holiday_<n>_days_past_easter`, `_add_holiday_<month>_<day>`, and various weekday-relative patterns. Methods like `_add_holiday_26_days_past_easter` are not explicitly defined but are dynamically generated when called.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2483
File: holidays/countries/turks_and_caicos_islands.py:117-118
Timestamp: 2025-05-13T13:23:11.375Z
Learning: The holidays library uses `_add_christmas_day_two` method to add Boxing Day holiday, not `_add_boxing_day`.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2593
File: holidays/calendars/islamic.py:3993-3994
Timestamp: 2025-06-04T10:09:28.732Z
Learning: In the holidays/calendars/islamic.py file, the Islamic calendar date methods in the _IslamicLunar class (like ali_al_rida_death_dates, ashura_dates, etc.) follow a consistent pattern of being single-line methods that return self._get_holiday(CONSTANT, year) without docstrings. New methods should follow this same pattern for consistency.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: tests/countries/test_mongolia.py:128-156
Timestamp: 2025-06-15T11:52:39.572Z
Learning: In the vacanza/holidays project tests, when testing holidays that span multiple consecutive days across many years (like Mongolia's National Festival spanning July 11-13), prefer explicit for loops over complex nested generator expressions with unpacking. The explicit loops are more readable, easier to maintain, and better communicate the testing intent even though the Big O complexity is equivalent.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: KJhellico
PR: vacanza/holidays#2593
File: holidays/countries/senegal.py:66-110
Timestamp: 2025-06-06T14:40:31.932Z
Learning: In the holidays library, within the _populate_public_holidays method, holidays should be arranged by calendar type (Islamic holidays first, then Gregorian holidays) without additional type grouping comments. The organization by calendar type is sufficient and follows the project's established conventions.

Learnt from: KJhellico
PR: vacanza/holidays#2437
File: holidays/calendars/tibetan.py:805-810
Timestamp: 2025-04-08T14:50:15.325Z
Learning: The standard behavior for calendar date methods in the holidays library is to return `(None, True)` when a requested year is not found in the date dictionary, rather than raising an exception or requiring documentation for out-of-range years.

Learnt from: KJhellico
PR: vacanza/holidays#2437
File: holidays/calendars/tibetan.py:805-810
Timestamp: 2025-04-08T14:50:15.325Z
Learning: The standard behavior for calendar date methods in the holidays library is to return `(None, True)` when a requested year is not found in the date dictionary, rather than raising an exception or requiring documentation for out-of-range years.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: KJhellico
PR: vacanza/holidays#2632
File: holidays/countries/solomon_islands.py:90-97
Timestamp: 2025-06-15T20:39:51.085Z
Learning: Solomon Islands Saturday → Friday holiday shift rule was systematically implemented only from around 2021-2022 onward, not consistently applied since 1979. The Public Holidays Act only explicitly mentions Sunday → Monday shifts, with Saturday shifts handled through discretionary ministerial gazette notices.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:21:59.302Z
Learning: In the Saint Vincent and the Grenadines holiday tests, for holidays without observed rules that only require a single assertHolidayName call, pass the holiday name directly as a string literal rather than storing it in a variable first for cleaner, more concise code.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: PPsyrius
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:73-77
Timestamp: 2025-04-03T12:36:41.201Z
Learning: In the Holidays library, comments explaining year restrictions for holidays should be placed above the year check conditional statement, not inside it. Example format:
```python
# reason why goes here
if start_year <= self._year <= end_year:
    # Holiday name
    self._add_holiday_function(tr("Holiday Name"))
```

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2490
File: holidays/countries/ethiopia.py:45-45
Timestamp: 2025-04-23T09:59:19.886Z
Learning: For the Ethiopia holidays class, it's appropriate to add a return type hint only to the `_is_leap_year` method to match the base class implementation in `holidays/holiday_base.py`, while keeping other methods without type hints to maintain consistency with other country implementations.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2593
File: holidays/calendars/islamic.py:3993-3994
Timestamp: 2025-06-04T10:09:28.732Z
Learning: In the holidays/calendars/islamic.py file, the Islamic calendar date methods in the _IslamicLunar class (like ali_al_rida_death_dates, ashura_dates, etc.) follow a consistent pattern of being single-line methods that return self._get_holiday(CONSTANT, year) without docstrings. New methods should follow this same pattern for consistency.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:52-64
Timestamp: 2025-04-05T04:47:27.213Z
Learning: For holiday tests in the vacanza/holidays project, structure tests by individual holidays rather than by years. Each test method should focus on a specific holiday and test it across multiple years (from start_year through 2050) using helper methods like `assertHolidayName`. For fixed holidays, use generators like `(f"{year}-01-01" for year in range(1991, 2051))`. For movable holidays, specify individual dates for specific years followed by a range check.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:21:59.302Z
Learning: In the Saint Vincent and the Grenadines holiday tests, for holidays without observed rules that only require a single assertHolidayName call, pass the holiday name directly as a string literal rather than storing it in a variable first for cleaner, more concise code.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:52-64
Timestamp: 2025-04-05T04:47:27.213Z
Learning: For holiday tests in the vacanza/holidays project, structure tests by individual holidays rather than by years. Each test method should focus on a specific holiday and test it across multiple years (from start_year through 2050) using helper methods like `assertHolidayName`. For fixed holidays, use generators like `(f"{year}-01-01" for year in range(1991, 2051))`. For movable holidays, specify individual dates for specific years followed by a range check.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:22-26
Timestamp: 2025-04-23T14:55:35.504Z
Learning: References in holidays classes should only be included if they're used for test case cross-checks or provide historical context about when holidays were added/removed, not just for the sake of having more references.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:22-26
Timestamp: 2025-04-23T14:55:35.504Z
Learning: References in holidays classes should only be included if they're used for test case cross-checks or provide historical context about when holidays were added/removed, not just for the sake of having more references.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2632
File: holidays/countries/solomon_islands.py:95-98
Timestamp: 2025-06-16T12:28:31.641Z
Learning: Library-wide holiday patterns and their optimizations should be handled at the base class level (like InternationalHolidays) rather than documenting workarounds in individual country modules. This maintains separation of concerns and avoids documentation duplication.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: KJhellico
PR: vacanza/holidays#2483
File: holidays/countries/turks_and_caicos_islands.py:117-118
Timestamp: 2025-05-13T13:23:11.375Z
Learning: The holidays library uses `_add_christmas_day_two` method to add Boxing Day holiday, not `_add_boxing_day`.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: PPsyrius
PR: vacanza/holidays#2642
File: holidays/countries/french_southern_territories.py:41-44
Timestamp: 2025-06-18T10:07:58.780Z
Learning: Territorial holiday classes that inherit from parent countries (like HolidaysAX from Finland, HolidaysSJ from Norway, HolidaysTF from France) follow a standard pattern of silently overriding self.subdiv in their _populate_public_holidays() method without validation, as this ensures they always use the correct subdivision code for their territory regardless of user input.

Learnt from: KJhellico
PR: vacanza/holidays#2631
File: holidays/countries/sint_maarten.py:94-95
Timestamp: 2025-06-14T20:43:15.370Z
Learning: The `_add_*` helper methods in the holidays library (such as `_add_christmas_day_two()`, `_add_labor_day()`, etc.) don't have default holiday names, so the name parameter should always be explicitly specified when calling these methods.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: holidays/countries/mongolia.py:140-146
Timestamp: 2025-06-15T11:50:44.366Z
Learning: The holidays library doesn't currently have helper functions like `_add_holiday_span` for adding consecutive multi-day holidays. Countries like Mongolia, Thailand, and Vietnam implement multi-day holiday spans using inline loops with `_timedelta(dt, delta)` pattern.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:48-50
Timestamp: 2025-06-14T11:05:21.250Z
Learning: In the holidays library, newer implementations use `start_year` to indicate the earliest year with complete holiday data coverage, not necessarily the first year a holiday existed. If a holiday system starts partway through a year (like Nauru's Public Holidays Act starting Jan 31, 1968), the start_year should be set to the following year (1969) to ensure users get full annual holiday coverage.

Learnt from: KJhellico
PR: vacanza/holidays#2606
File: holidays/countries/faroe_islands.py:62-67
Timestamp: 2025-06-15T15:24:53.055Z
Learning: The `HolidayBase` class uses `__getattr__` to dynamically implement `_add_holiday_*` methods through pattern matching, including patterns like `_add_holiday_<n>_days_past_easter`, `_add_holiday_<month>_<day>`, and various weekday-relative patterns. Methods like `_add_holiday_26_days_past_easter` are not explicitly defined but are dynamically generated when called.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: tests/countries/test_mongolia.py:128-156
Timestamp: 2025-06-15T11:52:39.572Z
Learning: In the vacanza/holidays project tests, when testing holidays that span multiple consecutive days across many years (like Mongolia's National Festival spanning July 11-13), prefer explicit for loops over complex nested generator expressions with unpacking. The explicit loops are more readable, easier to maintain, and better communicate the testing intent even though the Big O complexity is equivalent.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:52-64
Timestamp: 2025-04-05T04:47:27.213Z
Learning: For holiday tests in the vacanza/holidays project, structure tests by individual holidays rather than by years. Each test method should focus on a specific holiday and test it across multiple years (from start_year through 2050) using helper methods like `assertHolidayName`. For fixed holidays, use generators like `(f"{year}-01-01" for year in range(1991, 2051))`. For movable holidays, specify individual dates for specific years followed by a range check.

Learnt from: PPsyrius
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:73-77
Timestamp: 2025-04-03T12:36:41.201Z
Learning: In the Holidays library, comments explaining year restrictions for holidays should be placed above the year check conditional statement, not inside it. Example format:
```python
# reason why goes here
if start_year <= self._year <= end_year:
    # Holiday name
    self._add_holiday_function(tr("Holiday Name"))
```

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2593
File: holidays/calendars/islamic.py:3993-3994
Timestamp: 2025-06-04T10:09:28.732Z
Learning: In the holidays/calendars/islamic.py file, the Islamic calendar date methods in the _IslamicLunar class (like ali_al_rida_death_dates, ashura_dates, etc.) follow a consistent pattern of being single-line methods that return self._get_holiday(CONSTANT, year) without docstrings. New methods should follow this same pattern for consistency.

Learnt from: KJhellico
PR: vacanza/holidays#2437
File: holidays/calendars/tibetan.py:805-810
Timestamp: 2025-04-08T14:50:15.325Z
Learning: The standard behavior for calendar date methods in the holidays library is to return `(None, True)` when a requested year is not found in the date dictionary, rather than raising an exception or requiring documentation for out-of-range years.

Learnt from: KJhellico
PR: vacanza/holidays#2437
File: holidays/calendars/tibetan.py:805-810
Timestamp: 2025-04-08T14:50:15.325Z
Learning: The standard behavior for calendar date methods in the holidays library is to return `(None, True)` when a requested year is not found in the date dictionary, rather than raising an exception or requiring documentation for out-of-range years.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2522
File: holidays/countries/yemen.py:158-163
Timestamp: 2025-05-06T13:01:22.693Z
Learning: In the holidays library, the RAMADAN_BEGINNING_DATES dictionary in country-specific Islamic holiday classes (like YemenIslamicHolidays) is used indirectly through the backend. When a country class calls _add_holiday_29_ramadan(), the IslamicHolidays implementation uses the country's custom calendar dates to calculate the 29th day of Ramadan by adding 28 days to the beginning date.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: KJhellico
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:171-183
Timestamp: 2025-03-29T15:15:05.919Z
Learning: In the Fiji holidays implementation, the maintainers are aware of the need to extend the MAWLID_DATES dictionary beyond 2025 when future official references become available, and will do so when appropriate. No suggestions about extending this dictionary should be made in future reviews.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:21:59.302Z
Learning: In the Saint Vincent and the Grenadines holiday tests, for holidays without observed rules that only require a single assertHolidayName call, pass the holiday name directly as a string literal rather than storing it in a variable first for cleaner, more concise code.

Learnt from: PPsyrius
PR: vacanza/holidays#2632
File: holidays/countries/solomon_islands.py:95-98
Timestamp: 2025-06-16T12:28:31.641Z
Learning: Library-wide holiday patterns and their optimizations should be handled at the base class level (like InternationalHolidays) rather than documenting workarounds in individual country modules. This maintains separation of concerns and avoids documentation duplication.

Learnt from: PPsyrius
PR: vacanza/holidays#2643
File: holidays/countries/mauritius.py:171-184
Timestamp: 2025-06-19T02:34:14.456Z
Learning: In the holidays library, `_CustomIslamicHolidays` subclasses follow a consistent pattern of NOT having docstrings. They go directly to defining date dictionaries, as evidenced by Malaysia, Singapore, UAE, and dozens of other country implementations.

Learnt from: KJhellico
PR: vacanza/holidays#2530
File: tests/countries/test_andorra.py:23-28
Timestamp: 2025-05-06T21:07:11.577Z
Learning: In the holidays project, test methods for country holidays follow a standard form where year ranges are explicitly recreated in each test method rather than being stored as class variables, to maintain consistency across all country tests.

Learnt from: PPsyrius
PR: vacanza/holidays#2642
File: holidays/countries/france.py:300-319
Timestamp: 2025-06-18T10:21:01.376Z
Learning: In the France holidays implementation, legislative years for holiday changes should be hard-coded rather than extracted into constants, as this maintains consistency with the existing codebase pattern and provides historical accuracy for specific legislative acts.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:106-110
Timestamp: 2025-04-04T10:52:41.546Z
Learning: In the Guinea holidays implementation, observed Eid al-Fitr cases are covered by the test_eid_al_fitr_day() method, which tests both regular holiday dates and the observed dates when the holiday falls on a non-working day (for years >= 2023).

Learnt from: KJhellico
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:106-110
Timestamp: 2025-04-04T10:52:41.546Z
Learning: In the Guinea holidays implementation, observed Eid al-Fitr cases are properly covered by the test_eid_al_fitr_day() method, which tests both the regular holiday dates and the observed dates when the holiday falls on a non-working day (for years >= 2023).

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: KJhellico
PR: vacanza/holidays#2606
File: holidays/countries/faroe_islands.py:62-67
Timestamp: 2025-06-15T15:24:53.055Z
Learning: The `HolidayBase` class uses `__getattr__` to dynamically implement `_add_holiday_*` methods through pattern matching, including patterns like `_add_holiday_<n>_days_past_easter`, `_add_holiday_<month>_<day>`, and various weekday-relative patterns. Methods like `_add_holiday_26_days_past_easter` are not explicitly defined but are dynamically generated when called.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: KJhellico
PR: vacanza/holidays#2483
File: holidays/countries/turks_and_caicos_islands.py:117-118
Timestamp: 2025-05-13T13:23:11.375Z
Learning: The holidays library uses `_add_christmas_day_two` method to add Boxing Day holiday, not `_add_boxing_day`.

Learnt from: KJhellico
PR: vacanza/holidays#2635
File: holidays/countries/bhutan.py:13-16
Timestamp: 2025-06-16T14:08:09.492Z
Learning: In the holidays library, translation is performed in the `_add_holiday` methods, not at the string level. Holiday strings passed to `_add_holiday_*` methods are processed through the translation machinery within those methods, so using `tr()` or `self.tr()` wrappers is unnecessary.

Learnt from: KJhellico
PR: vacanza/holidays#2631
File: holidays/countries/sint_maarten.py:94-95
Timestamp: 2025-06-14T20:43:15.370Z
Learning: The `_add_*` helper methods in the holidays library (such as `_add_christmas_day_two()`, `_add_labor_day()`, etc.) don't have default holiday names, so the name parameter should always be explicitly specified when calling these methods.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: holidays/countries/mongolia.py:140-146
Timestamp: 2025-06-15T11:50:44.366Z
Learning: The holidays library doesn't currently have helper functions like `_add_holiday_span` for adding consecutive multi-day holidays. Countries like Mongolia, Thailand, and Vietnam implement multi-day holiday spans using inline loops with `_timedelta(dt, delta)` pattern.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:48-50
Timestamp: 2025-06-14T11:05:21.250Z
Learning: In the holidays library, newer implementations use `start_year` to indicate the earliest year with complete holiday data coverage, not necessarily the first year a holiday existed. If a holiday system starts partway through a year (like Nauru's Public Holidays Act starting Jan 31, 1968), the start_year should be set to the following year (1969) to ensure users get full annual holiday coverage.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:73-77
Timestamp: 2025-04-03T12:36:41.201Z
Learning: In the Holidays library, comments explaining year restrictions for holidays should be placed above the year check conditional statement, not inside it. Example format:
```python
# reason why goes here
if start_year <= self._year <= end_year:
    # Holiday name
    self._add_holiday_function(tr("Holiday Name"))
```

Learnt from: PPsyrius
PR: vacanza/holidays#2490
File: holidays/countries/ethiopia.py:45-45
Timestamp: 2025-04-23T09:59:19.886Z
Learning: For the Ethiopia holidays class, it's appropriate to add a return type hint only to the `_is_leap_year` method to match the base class implementation in `holidays/holiday_base.py`, while keeping other methods without type hints to maintain consistency with other country implementations.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:52-64
Timestamp: 2025-04-05T04:47:27.213Z
Learning: For holiday tests in the vacanza/holidays project, structure tests by individual holidays rather than by years. Each test method should focus on a specific holiday and test it across multiple years (from start_year through 2050) using helper methods like `assertHolidayName`. For fixed holidays, use generators like `(f"{year}-01-01" for year in range(1991, 2051))`. For movable holidays, specify individual dates for specific years followed by a range check.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: holidays/countries/mongolia.py:140-146
Timestamp: 2025-06-15T11:50:44.366Z
Learning: The holidays library doesn't currently have helper functions like `_add_holiday_span` for adding consecutive multi-day holidays. Countries like Mongolia, Thailand, and Vietnam implement multi-day holiday spans using inline loops with `_timedelta(dt, delta)` pattern.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:24-26
Timestamp: 2025-03-30T20:18:46.006Z
Learning: In the holidays library, country classes do not directly implement `_populate()`. Instead, they implement specialized methods like `_populate_public_holidays()`, and the base class `HolidayBase` handles the orchestration by calling these specialized methods.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2593
File: holidays/calendars/islamic.py:3993-3994
Timestamp: 2025-06-04T10:09:28.732Z
Learning: In the holidays/calendars/islamic.py file, the Islamic calendar date methods in the _IslamicLunar class (like ali_al_rida_death_dates, ashura_dates, etc.) follow a consistent pattern of being single-line methods that return self._get_holiday(CONSTANT, year) without docstrings. New methods should follow this same pattern for consistency.

Learnt from: KJhellico
PR: vacanza/holidays#2631
File: holidays/countries/sint_maarten.py:94-95
Timestamp: 2025-06-14T20:43:15.370Z
Learning: The `_add_*` helper methods in the holidays library (such as `_add_christmas_day_two()`, `_add_labor_day()`, etc.) don't have default holiday names, so the name parameter should always be explicitly specified when calling these methods.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2635
File: holidays/countries/bhutan.py:13-16
Timestamp: 2025-06-16T14:08:09.492Z
Learning: In the holidays library, translation is performed in the `_add_holiday` methods, not at the string level. Holiday strings passed to `_add_holiday_*` methods are processed through the translation machinery within those methods, so using `tr()` or `self.tr()` wrappers is unnecessary.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: PPsyrius
PR: vacanza/holidays#2537
File: holidays/countries/finland.py:249-253
Timestamp: 2025-05-10T04:02:13.815Z
Learning: Holiday name comments directly above tr() function calls in the holidays package should only contain the holiday name itself (e.g., "# Independence Day.") without any additional context, dates, or historical information.

Learnt from: KJhellico
PR: vacanza/holidays#2483
File: holidays/countries/turks_and_caicos_islands.py:117-118
Timestamp: 2025-05-13T13:23:11.375Z
Learning: The holidays library uses `_add_christmas_day_two` method to add Boxing Day holiday, not `_add_boxing_day`.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: tests/countries/test_mongolia.py:128-156
Timestamp: 2025-06-15T11:52:39.572Z
Learning: In the vacanza/holidays project tests, when testing holidays that span multiple consecutive days across many years (like Mongolia's National Festival spanning July 11-13), prefer explicit for loops over complex nested generator expressions with unpacking. The explicit loops are more readable, easier to maintain, and better communicate the testing intent even though the Big O complexity is equivalent.

Learnt from: PPsyrius
PR: vacanza/holidays#2632
File: holidays/countries/solomon_islands.py:95-98
Timestamp: 2025-06-16T12:28:31.641Z
Learning: Library-wide holiday patterns and their optimizations should be handled at the base class level (like InternationalHolidays) rather than documenting workarounds in individual country modules. This maintains separation of concerns and avoids documentation duplication.

Learnt from: PPsyrius
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:73-77
Timestamp: 2025-04-03T12:36:41.201Z
Learning: In the Holidays library, comments explaining year restrictions for holidays should be placed above the year check conditional statement, not inside it. Example format:
```python
# reason why goes here
if start_year <= self._year <= end_year:
    # Holiday name
    self._add_holiday_function(tr("Holiday Name"))
```

Learnt from: PPsyrius
PR: vacanza/holidays#2490
File: holidays/countries/ethiopia.py:45-45
Timestamp: 2025-04-23T09:59:19.886Z
Learning: For the Ethiopia holidays class, it's appropriate to add a return type hint only to the `_is_leap_year` method to match the base class implementation in `holidays/holiday_base.py`, while keeping other methods without type hints to maintain consistency with other country implementations.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2593
File: holidays/calendars/islamic.py:3993-3994
Timestamp: 2025-06-04T10:09:28.732Z
Learning: In the holidays/calendars/islamic.py file, the Islamic calendar date methods in the _IslamicLunar class (like ali_al_rida_death_dates, ashura_dates, etc.) follow a consistent pattern of being single-line methods that return self._get_holiday(CONSTANT, year) without docstrings. New methods should follow this same pattern for consistency.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: KJhellico
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:106-110
Timestamp: 2025-04-04T10:52:41.546Z
Learning: In the Guinea holidays implementation, observed Eid al-Fitr cases are properly covered by the test_eid_al_fitr_day() method, which tests both the regular holiday dates and the observed dates when the holiday falls on a non-working day (for years >= 2023).

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:52-64
Timestamp: 2025-04-05T04:47:27.213Z
Learning: For holiday tests in the vacanza/holidays project, structure tests by individual holidays rather than by years. Each test method should focus on a specific holiday and test it across multiple years (from start_year through 2050) using helper methods like `assertHolidayName`. For fixed holidays, use generators like `(f"{year}-01-01" for year in range(1991, 2051))`. For movable holidays, specify individual dates for specific years followed by a range check.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: KJhellico
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:106-110
Timestamp: 2025-04-04T10:52:41.546Z
Learning: In the Guinea holidays implementation, observed Eid al-Fitr cases are covered by the test_eid_al_fitr_day() method, which tests both regular holiday dates and the observed dates when the holiday falls on a non-working day (for years >= 2023).

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:185-188
Timestamp: 2025-03-19T16:53:00.375Z
Learning: In the Fiji holidays implementation, the `special_public_holidays_observed` dictionary in `FijiStaticHolidays` is only used for exceptions to the normal observance rules, not for documenting all holidays. Only 2019's Constitution Day needed a special entry as it didn't follow the standard patterns.

Learnt from: PPsyrius
PR: vacanza/holidays#2354
File: holidays/countries/fiji.py:146-159
Timestamp: 2025-03-19T16:54:58.657Z
Learning: In the holidays library implementation, explicit holiday dates (like Diwali in Fiji) are only defined for historical years with official sources (2016-2025). Future dates beyond the explicitly defined range are automatically calculated by methods like `_add_diwali`, which provide approximations when official dates aren't yet available.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants internally through parent class implementations even when these constants don't appear directly in the file. Removing imports that seem unused based on a simple text search could break functionality.

Learnt from: PPsyrius
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:78-90
Timestamp: 2025-06-13T12:18:03.539Z
Learning: The holidays codebase now uses the constructor signature pattern `__init__(self, *args, islamic_show_estimated: bool = True, **kwargs)` across country classes.

Learnt from: PPsyrius
PR: vacanza/holidays#2490
File: holidays/countries/ethiopia.py:45-45
Timestamp: 2025-04-23T09:59:19.886Z
Learning: For the Ethiopia holidays class, it's appropriate to add a return type hint only to the `_is_leap_year` method to match the base class implementation in `holidays/holiday_base.py`, while keeping other methods without type hints to maintain consistency with other country implementations.

Learnt from: KJhellico
PR: vacanza/holidays#2530
File: tests/countries/test_andorra.py:23-28
Timestamp: 2025-05-06T21:07:11.577Z
Learning: In the holidays project, test methods for country holidays follow a standard form where year ranges are explicitly recreated in each test method rather than being stored as class variables, to maintain consistency across all country tests.

Learnt from: PPsyrius
PR: vacanza/holidays#2632
File: holidays/countries/solomon_islands.py:95-98
Timestamp: 2025-06-16T12:28:31.641Z
Learning: Library-wide holiday patterns and their optimizations should be handled at the base class level (like InternationalHolidays) rather than documenting workarounds in individual country modules. This maintains separation of concerns and avoids documentation duplication.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:52-64
Timestamp: 2025-04-05T04:47:27.213Z
Learning: For holiday tests in the vacanza/holidays project, structure tests by individual holidays rather than by years. Each test method should focus on a specific holiday and test it across multiple years (from start_year through 2050) using helper methods like `assertHolidayName`. For fixed holidays, use generators like `(f"{year}-01-01" for year in range(1991, 2051))`. For movable holidays, specify individual dates for specific years followed by a range check.

Learnt from: PPsyrius
PR: vacanza/holidays#2398
File: holidays/countries/guinea.py:73-77
Timestamp: 2025-04-03T12:36:41.201Z
Learning: In the Holidays library, comments explaining year restrictions for holidays should be placed above the year check conditional statement, not inside it. Example format:
```python
# reason why goes here
if start_year <= self._year <= end_year:
    # Holiday name
    self._add_holiday_function(tr("Holiday Name"))
```

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2593
File: holidays/calendars/islamic.py:3993-3994
Timestamp: 2025-06-04T10:09:28.732Z
Learning: In the holidays/calendars/islamic.py file, the Islamic calendar date methods in the _IslamicLunar class (like ali_al_rida_death_dates, ashura_dates, etc.) follow a consistent pattern of being single-line methods that return self._get_holiday(CONSTANT, year) without docstrings. New methods should follow this same pattern for consistency.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: KJhellico
PR: vacanza/holidays#2614
File: holidays/countries/guyana.py:146-179
Timestamp: 2025-06-14T20:12:37.212Z
Learning: The `_CustomHinduHolidays` mechanism works through `_CustomCalendarType` metaclass which renames public attributes (like `DIWALI_INDIA_DATES`) with a postfix, allowing `_HinduLunisolar::_get_holiday` to find and use custom holiday dates. When `_add_diwali_india()` is called, it uses the custom dates if available rather than calculated dates.

Learnt from: PPsyrius
PR: vacanza/holidays#2601
File: holidays/countries/mongolia.py:140-146
Timestamp: 2025-06-15T11:50:44.366Z
Learning: The holidays library doesn't currently have helper functions like `_add_holiday_span` for adding consecutive multi-day holidays. Countries like Mongolia, Thailand, and Vietnam implement multi-day holiday spans using inline loops with `_timedelta(dt, delta)` pattern.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: holidays/countries/nepal.py:203-208
Timestamp: 2025-05-01T19:13:44.664Z
Learning: Multiple holidays on the same date are properly handled in the holidays library. When multiple `_add_...` methods are called with different holiday names for the same date, both holidays are preserved rather than the latter overwriting the former. This happens because the `__setitem__` method in `HolidayBase` merges multiple holidays on the same date by combining their names.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2409
File: holidays/countries/qatar.py:27-46
Timestamp: 2025-04-03T16:58:27.175Z
Learning: In the holidays library, method names like `_add_holiday_2nd_tue_of_feb()` and `_add_holiday_1st_sun_of_mar()` use calendar constants like FEB, TUE, MAR, and SUN internally through parent class implementations even when these constants don't appear directly in the file.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2522
File: holidays/countries/yemen.py:158-163
Timestamp: 2025-05-06T13:01:22.693Z
Learning: In the holidays library, the RAMADAN_BEGINNING_DATES dictionary in country-specific Islamic holiday classes (like YemenIslamicHolidays) is used indirectly through the backend. When a country class calls _add_holiday_29_ramadan(), the IslamicHolidays implementation uses the country's custom calendar dates to calculate the 29th day of Ramadan by adding 28 days to the beginning date.

Learnt from: KJhellico
PR: vacanza/holidays#2608
File: tests/countries/test_saint_vincent_and_the_grenadines.py:162-178
Timestamp: 2025-07-02T18:17:53.342Z
Learning: In the Saint Vincent and the Grenadines holidays implementation, New Year's Day is added without observed rules using `_add_new_years_day()` and should not include observed rule testing in its test method. Only holidays explicitly wrapped with `_add_observed()` have observed behavior.

Learnt from: PPsyrius
PR: vacanza/holidays#2609
File: holidays/countries/nauru.py:57-60
Timestamp: 2025-06-14T11:04:31.180Z
Learning: In the holidays library, the base `HolidayBase._populate()` method already includes a guard clause that prevents holiday population methods like `_populate_public_holidays()` from being called when the year is before `start_year` or after `end_year`. Therefore, individual country implementations do not need to add their own guard clauses for years before independence or other start dates.

Learnt from: KJhellico
PR: vacanza/holidays#2398
File: tests/countries/test_guinea.py:30-39
Timestamp: 2025-04-02T13:58:21.457Z
Learning: Second Republic Day in Guinea was abolished by at least 2022 according to Decree D/2022/0526/PRG/CNRD/SGG, and this is correctly implemented in the holidays library by only including the holiday for years up to and including 2021.

Learnt from: PPsyrius
PR: vacanza/holidays#2643
File: holidays/countries/mauritius.py:144-169
Timestamp: 2025-06-19T02:34:18.382Z
Learning: Custom holiday classes that extend _CustomHinduHolidays, _CustomIslamicHolidays, _CustomBuddhistHolidays, etc. in the holidays library do not use docstrings. They follow a pattern of using only inline comments above date dictionaries, as seen in Malaysia, Singapore, UAE, and other country implementations.

Learnt from: KJhellico
PR: vacanza/holidays#2465
File: holidays/countries/suriname.py:219-251
Timestamp: 2025-04-13T19:10:31.502Z
Learning: The `_CustomIslamicHolidays` classes in this project contain only exact verified holiday dates from reliable sources, rather than calculated or estimated future dates. This is by design to ensure accuracy, particularly for religious holidays that may follow lunar calendars or depend on local observations.

Learnt from: KJhellico
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:551-554
Timestamp: 2025-05-01T19:19:42.346Z
Learning: In the holidays library, when multiple holidays fall on the same date, their names are always sorted alphabetically (in __setitem__ of HolidayBase), so the order of addition does not affect the resulting string.

Learnt from: KJhellico
PR: vacanza/holidays#2483
File: holidays/countries/turks_and_caicos_islands.py:117-118
Timestamp: 2025-05-13T13:23:11.375Z
Learning: The holidays library uses `_add_christmas_day_two` method to add Boxing Day holiday, not `_add_boxing_day`.