Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: When adding a new country in vacanza/holidays, also re-export it in holidays/countries/__init__.py (e.g., from .liberia import Liberia, LR, LBR) so tests and users can import from holidays.countries consistently.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: In holidays/countries/__init__.py, re-export country classes using absolute imports (e.g., 'from holidays.countries.liberia import Liberia, LR, LBR') and keep alphabetical ordering (e.g., Lesotho, Liberia, Libya). Avoid relative imports in this file.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: When adding a new country in vacanza/holidays, also re-export it in holidays/countries/__init__.py (e.g., from .liberia import Liberia, LR, LBR) so tests and users can import from holidays.countries consistently.

Learnt from: KJhellico
PR: vacanza/holidays#2778
File: tests/countries/test_kiribati.py:15-15
Timestamp: 2025-08-09T18:31:23.218Z
Learning: In the holidays project test files, the standard import pattern is `from holidays.countries.<country> import Country, CODE1, CODE2` (used in ~97% of test files), not `from holidays.countries import Country, CODE1, CODE2`. Only a few exceptions (Suriname, Sierra Leone, Mauritius, Mali, Ivory Coast, Guyana) use the aggregated import pattern.

Learnt from: KJhellico
PR: vacanza/holidays#2820
File: holidays/countries/__init__.py:199-203
Timestamp: 2025-08-31T19:34:20.731Z
Learning: In Saint Helena, Ascension and Tristan da Cunha holidays implementation (holidays/countries/saint_helena_ascension_and_tristan_da_cunha.py), only three classes are defined: SaintHelenaAscensionAndTristanDaCunha (main class), SH (alias), and SHN (alias). There is no HolidaysSH class, despite it being referenced in the registry.py entry.

Learnt from: KJhellico
PR: vacanza/holidays#2719
File: README.md:108-108
Timestamp: 2025-07-12T20:54:28.749Z
Learning: In PR #2719 adding Faroe Islands, KJhellico confirmed that the country count in README.md should be updated from 213 to 214, making 214 the accurate total after this addition.

Learnt from: KJhellico
PR: vacanza/holidays#2606
File: README.md:562-568
Timestamp: 2025-06-06T16:02:09.910Z
Learning: The README.md country table displays ISO 3166-1 alpha-2 codes only in the "Code" column. Alpha-3 codes or country aliases should not be included in this table format, maintaining consistency with all other country entries.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:85-86
Timestamp: 2025-04-05T04:29:38.042Z
Learning: For testing holiday implementations in the vacanza/holidays repository, recommend using `from tests.common import CommonCountryTests` as the base class instead of directly using `unittest.TestCase` to maintain consistency with project conventions and leverage common test utilities.

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#2881
File: tests/countries/test_algeria.py:28-30
Timestamp: 2025-09-18T03:19:23.722Z
Learning: In the vacanza/holidays project, tests now use self.start_year and self.end_year from the TestCase class instead of country-specific aliases (like DZ.start_year) for start_year and end_year references. This approach provides the test framework with better control over test year ranges rather than being tied to specific country start years.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_saint_helena_ascension_and_tristan_da_cunha.py:209-209
Timestamp: 2025-09-14T17:17:14.387Z
Learning: In tests/countries/test_saint_helena_ascension_and_tristan_da_cunha.py, the explicit loop iteration pattern for subdivision-specific holiday checks (like Anniversary Day for TA subdivision) is intentionally preferred over using assertSubdivTa helper methods, as confirmed by PPsyrius.

Learnt from: PPsyrius
PR: vacanza/holidays#2615
File: tests/countries/test_anguilla.py:1-12
Timestamp: 2025-06-16T15:48:48.680Z
Learning: Test files in the holidays repository follow a standardized structure without module or class docstrings. All country test files use the same pattern: license header, imports, and class definition (`class Test{Country}(CommonCountryTests, TestCase):`) without docstrings. This is an established codebase convention that should be maintained for consistency.

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#2416
File: tests/countries/test_turkmenistan.py:31-49
Timestamp: 2025-04-05T04:50:40.752Z
Learning: For Turkmenistan holiday tests, use this class structure: `class TestTurkmenistan(CommonCountryTests, TestCase)` with imports `from unittest import TestCase`, `from holidays.countries import Turkmenistan, TM, TKM`, and `from tests.common import CommonCountryTests`. Ensure to call `super().setUp()` in the setUp method.

Learnt from: PPsyrius
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:499-536
Timestamp: 2025-04-05T06:49:06.217Z
Learning: In the holidays project, test files follow a dual testing approach: individual methods test specific holidays across multiple years, while comprehensive year-specific tests (e.g., `test_2025`) verify all holidays for a specific year in a single assertion. Both approaches serve different testing purposes and complement each other.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:52-64
Timestamp: 2025-04-05T04:33:53.254Z
Learning: For Turkmenistan holiday tests, recommend using CommonCountryTests as the base class rather than unittest.TestCase to follow project conventions, be consistent with other country test files, and gain access to common test utilities.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2852
File: tests/countries/test_tajikistan.py:26-28
Timestamp: 2025-08-24T13:01:51.370Z
Learning: In the holidays project country test files, the universally adopted standard method name for testing country aliases (ISO codes) is `test_country_aliases`. This naming convention is used consistently across all 235+ country test files in the repository, with no exceptions using `test_aliases`.

Learnt from: KJhellico
PR: vacanza/holidays#2684
File: holidays/locale/it/LC_MESSAGES/SM.po:13-13
Timestamp: 2025-06-28T10:39:19.185Z
Learning: In the holidays project, .po file header comments use the format "# [Country] holidays." for default language files (without trailing hash) and "# [Country] holidays [locale] localization." for non-default language files (also without trailing hash).

Learnt from: KJhellico
PR: vacanza/holidays#2259
File: holidays/locale/en_IN/LC_MESSAGES/IN.po:30-299
Timestamp: 2025-03-05T17:51:00.633Z
Learning: In the Holidays project, .po files for a country's default locale use empty msgstr fields as a standard convention.

Learnt from: KJhellico
PR: vacanza/holidays#2388
File: holidays/locale/en_CI/LC_MESSAGES/CI.po:88-88
Timestamp: 2025-03-30T18:25:07.087Z
Learning: In the holidays library, localization files have a specific structure: message comments are in standard English (en_US) describing the holiday, while actual translations (msgstr) should use the locale-specific terminology (e.g., en_CI for Ivory Coast English). For example, "Night of Power" in standard English is translated as "Lailatou-Kadr" in Ivory Coast English.

Learnt from: KJhellico
PR: vacanza/holidays#2530
File: holidays/locale/ca/LC_MESSAGES/AD.po:31-40
Timestamp: 2025-05-06T15:25:44.333Z
Learning: In the Holidays project, msgid fields in localization files contain strings in the entity's default language (as defined by default_language attribute), not English source strings as in standard gettext implementations.

Learnt from: PPsyrius
PR: vacanza/holidays#2438
File: holidays/locale/ar_IQ/LC_MESSAGES/IQ.po:35-81
Timestamp: 2025-04-17T17:08:48.082Z
Learning: In holiday PO files, when the file represents the default language of an entity (e.g., ar_IQ for Iraq), no translations in `msgstr` are required as the `msgid` values are already in the target language.

Learnt from: PPsyrius
PR: vacanza/holidays#2402
File: holidays/locale/en_TT/LC_MESSAGES/TT.po:46-48
Timestamp: 2025-04-05T08:12:19.986Z
Learning: In the holidays library, localization (PO) files follow this convention: comments (#.) always use American English (en_US) spelling, while the msgid content follows the locale-specific spelling standards of the target language.

Learnt from: KJhellico
PR: vacanza/holidays#2676
File: holidays/locale/en_US/LC_MESSAGES/TN.po:17-28
Timestamp: 2025-06-26T15:34:35.476Z
Learning: In the holidays project, .po file header metadata updates (version numbers, revision dates, translator information) are legitimate changes when part of localization work and don't require `make l10n` regeneration. The `make l10n` command is primarily for formatting fixes and missing translator comments, not for intentional metadata updates.

Learnt from: ankushhKapoor
PR: vacanza/holidays#2601
File: holidays/locale/en_MN/LC_MESSAGES/MN.po:13-14
Timestamp: 2025-06-11T18:32:25.595Z
Learning: For non-default locale `.po` files, the header comment format is:
`# <Country> holidays <locale> localization.` (no trailing hash).

Learnt from: PPsyrius
PR: vacanza/holidays#2537
File: holidays/locale/th/LC_MESSAGES/AX.po:15-27
Timestamp: 2025-05-10T04:35:01.221Z
Learning: The localization (.po) files for Åland Islands (AX) are intentionally left as stubs without translations because Åland Islands is implemented as a subdivision of Finland (code "01"). Holiday translations are handled through the Finland (FI) localization files instead.

Learnt from: KJhellico
PR: vacanza/holidays#2687
File: holidays/locale/en_US/LC_MESSAGES/CF.po:13-28
Timestamp: 2025-06-29T09:37:35.283Z
Learning: In the holidays project, .po files follow a standard formatting convention where there is always a blank line after the metadata header section (after the "X-Source-Language" line). This blank line separates the header from the actual translation content and should not be removed.

Learnt from: PPsyrius
PR: vacanza/holidays#2843
File: holidays/countries/burundi.py:63-101
Timestamp: 2025-08-21T04:56:03.780Z
Learning: In the holidays library, countries with localization support consistently use tr() wrappers around holiday names when calling _add_* methods (e.g., self._add_new_years_day(tr("Holiday Name"))). This is the established pattern across United States, Thailand, and other l10n-enabled countries, contrary to any suggestion that translation is handled internally by _add_* methods.

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: KJhellico
PR: vacanza/holidays#2635
File: README.md:108-110
Timestamp: 2025-08-03T12:59:53.286Z
Learning: Always verify country counts in the COUNTRIES dictionary by checking the current count in the COUNTRIES dictionary in holidays/registry.py directly, rather than relying on information from previous PRs, as the count changes frequently with new country additions.

Learnt from: KJhellico
PR: vacanza/holidays#2623
File: README.md:0-0
Timestamp: 2025-07-10T11:00:13.195Z
Learning: The COUNTRIES dictionary in holidays/registry.py contains 211 entries as confirmed by KJhellico in PR #2623, not 214 as previously calculated.

Learnt from: KJhellico
PR: vacanza/holidays#2687
File: README.md:108-108
Timestamp: 2025-07-15T15:00:32.728Z
Learning: When verifying country counts in the holidays library, always check the current count in the COUNTRIES dictionary in holidays/registry.py rather than relying on previously recorded counts, as new countries may have been added in merged PRs.

Learnt from: KJhellico
PR: vacanza/holidays#2763
File: README.md:108-110
Timestamp: 2025-08-08T10:33:55.695Z
Learning: When verifying the country total in holidays/registry.py, isolate between '^COUNTRIES:' and '^FINANCIAL:' and count only lines matching the strict key pattern '^\s*"[a-z0-9_ ]+":\s*\(' to avoid overcounting non-entry quoted lines. As of PR vacanza/holidays#2763, this yields 227 entries.

Learnt from: KJhellico
PR: vacanza/holidays#2831
File: README.md:108-108
Timestamp: 2025-08-24T11:55:06.810Z
Learning: The actual count of countries in the holidays library should always be verified by counting entries in the COUNTRIES dictionary in holidays/registry.py using `grep -E '^\s*"[a-z_]+"\s*:' holidays/registry.py | wc -l`, rather than making assumptions about incremental changes.

Learnt from: KJhellico
PR: vacanza/holidays#2720
File: README.md:108-110
Timestamp: 2025-07-17T11:07:04.986Z
Learning: Always verify country counts in the holidays library by checking the current count in the COUNTRIES dictionary in holidays/registry.py directly, rather than relying on information from previous PRs, as the count changes frequently with new country additions.

Learnt from: PPsyrius
PR: vacanza/holidays#2716
File: holidays/registry.py:164-164
Timestamp: 2025-07-14T19:32:44.256Z
Learning: The COUNTRIES dictionary in holidays/registry.py contains exactly 215 entries as of PR #2716, with FINANCIAL dictionary entries (4 total) being tracked separately and not included in the country count for README.md.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: When adding a new country in vacanza/holidays, also re-export it in holidays/countries/__init__.py (e.g., from .liberia import Liberia, LR, LBR) so tests and users can import from holidays.countries consistently.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: In holidays/countries/__init__.py, re-export country classes using absolute imports (e.g., 'from holidays.countries.liberia import Liberia, LR, LBR') and keep alphabetical ordering (e.g., Lesotho, Liberia, Libya). Avoid relative imports in this file.

Learnt from: KJhellico
PR: vacanza/holidays#2687
File: README.md:108-108
Timestamp: 2025-07-15T15:00:32.728Z
Learning: When verifying country counts in the holidays library, always check the current count in the COUNTRIES dictionary in holidays/registry.py rather than relying on previously recorded counts, as new countries may have been added in merged PRs.

Learnt from: KJhellico
PR: vacanza/holidays#2635
File: README.md:108-110
Timestamp: 2025-08-03T12:59:53.286Z
Learning: Always verify country counts in the COUNTRIES dictionary by checking the current count in the COUNTRIES dictionary in holidays/registry.py directly, rather than relying on information from previous PRs, as the count changes frequently with new country additions.

Learnt from: KJhellico
PR: vacanza/holidays#2820
File: holidays/countries/__init__.py:199-203
Timestamp: 2025-08-31T19:34:20.731Z
Learning: In Saint Helena, Ascension and Tristan da Cunha holidays implementation (holidays/countries/saint_helena_ascension_and_tristan_da_cunha.py), only three classes are defined: SaintHelenaAscensionAndTristanDaCunha (main class), SH (alias), and SHN (alias). There is no HolidaysSH class, despite it being referenced in the registry.py entry.

Learnt from: KJhellico
PR: vacanza/holidays#2820
File: holidays/countries/__init__.py:199-203
Timestamp: 2025-08-31T19:34:20.731Z
Learning: In Saint Helena, Ascension and Tristan da Cunha holidays implementation (holidays/countries/saint_helena_ascension_and_tristan_da_cunha.py), only three classes are defined: SaintHelenaAscensionAndTristanDaCunha (main class), SH (alias), and SHN (alias). There is no HolidaysSH class, despite it being referenced in the registry.py entry.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: In holidays/countries/__init__.py, re-export country classes using absolute imports (e.g., 'from holidays.countries.liberia import Liberia, LR, LBR') and keep alphabetical ordering (e.g., Lesotho, Liberia, Libya). Avoid relative imports in this 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: KJhellico
PR: vacanza/holidays#2437
File: holidays/countries/bhutan.py:27-30
Timestamp: 2025-04-08T14:46:10.656Z
Learning: For country classes in the holidays library, there's no need to explicitly specify `supported_categories = (PUBLIC,)` when PUBLIC is the only category being used, as it's already the default category inherited from HolidayBase.

Learnt from: KJhellico
PR: vacanza/holidays#2525
File: holidays/countries/togo.py:0-0
Timestamp: 2025-05-04T10:29:46.780Z
Learning: When a country class in the holidays library uses additional categories beyond PUBLIC, the `supported_categories` tuple should contain all categories, including PUBLIC. Only when PUBLIC is the only category being used should it be omitted from `supported_categories`.

Learnt from: KJhellico
PR: vacanza/holidays#2854
File: tests/countries/test_sudan.py:29-31
Timestamp: 2025-09-12T21:37:10.710Z
Learning: For countries in the holidays library that only use the default PUBLIC category (like Sudan), there's no need to specify `categories=Sudan.supported_categories` in test_no_holidays methods, as it would be equivalent to the default behavior.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_antigua_and_barbuda.py:27-29
Timestamp: 2025-09-14T16:19:23.651Z
Learning: For Antigua and Barbuda in the holidays library, only the default PUBLIC category is used, so there's no need to specify `categories=AntiguaAndBarbuda.supported_categories` in test_no_holidays methods, as it would be equivalent to the default behavior and AntiguaAndBarbuda doesn't define supported_categories.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_bolivia.py:29-29
Timestamp: 2025-09-19T10:01:41.205Z
Learning: For Bolivia in the holidays library, only the default PUBLIC category is used, so there's no need to specify `categories=Bolivia.supported_categories` in test_no_holidays methods, as it would be equivalent to the default behavior and Bolivia doesn't define supported_categories.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_djibouti.py:27-29
Timestamp: 2025-09-14T16:10:02.766Z
Learning: For Djibouti in the holidays library, only the default PUBLIC category is used, so there's no need to specify `categories=Djibouti.supported_categories` in test_no_holidays methods, as it would be equivalent to the default behavior and Djibouti doesn't define supported_categories.

Learnt from: PPsyrius
PR: vacanza/holidays#2794
File: holidays/groups/international.py:0-0
Timestamp: 2025-08-12T17:39:49.804Z
Learning: Ethiopian New Year (Enkutatash) calculation uses `is_ethiopian_leap_year(self._year)` instead of `isleap(self._year + 1)` to properly handle century edge cases. Ethiopian leap years follow Julian rules (every 4 years without exception) while Gregorian leap years have century exceptions, causing different results around years like 2100.

Learnt from: PPsyrius
PR: vacanza/holidays#2794
File: holidays/groups/international.py:0-0
Timestamp: 2025-08-12T17:39:49.804Z
Learning: Ethiopian New Year (Enkutatash) calculation correctly uses `is_ethiopian_leap_year(self._year)` instead of `isleap(self._year + 1)` to properly handle century edge cases. The Ethiopian function `(year + 1) % 4 == 0` checks if the next year is divisible by 4 using Julian/Ethiopian rules (no century exceptions), while `isleap()` applies Gregorian century rules. This difference is crucial around years like 2100 where the two calendar systems diverge.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:86-88
Timestamp: 2025-04-23T09:22:41.753Z
Learning: For holiday definitions in the holidays package, keep comments simple with just the holiday name (e.g., "# Independence Day.") rather than including dates or historical context, as the function names already encode the date information.

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: PPsyrius
PR: vacanza/holidays#2831
File: holidays/countries/south_sudan.py:21-30
Timestamp: 2025-08-25T10:51:08.068Z
Learning: In the holidays library, references in country/market holiday implementations should be ordered as follows: Wikipedia links for the country/market holidays first, then country-specific official sources for newer implementations, then Wikipedia links for each individual non-standard holiday if any are required. Official government sources should not be placed first ahead of Wikipedia links.

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, multiple holidays on the same date are sorted alphabetically internally, so the order in which holidays are added does not affect the resulting holiday name string when multiple holidays occur on the same date.

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#2928
File: holidays/countries/algeria.py:16-22
Timestamp: 2025-09-16T04:11:33.513Z
Learning: In the holidays library, country class base inheritance follows alphabetical ordering after HolidayBase. For example, Algeria correctly uses: HolidayBase, ChristianHolidays, HebrewCalendarHolidays, InternationalHolidays, IslamicHolidays (alphabetical after the required HolidayBase first position).

Learnt from: PPsyrius
PR: vacanza/holidays#2537
File: tests/countries/test_finland.py:23-26
Timestamp: 2025-05-09T18:36:09.607Z
Learning: The holidays project prioritizes complete historical coverage in tests, verifying holidays from their first year of observance (e.g., 1853 for Finland) through future projections, rather than using shorter sliding windows.

Learnt from: PPsyrius
PR: vacanza/holidays#2874
File: holidays/countries/nigeria.py:31-44
Timestamp: 2025-08-30T22:55:34.525Z
Learning: For Nigeria holiday implementation reference ordering: The current ordering with Wikipedia first, followed by official sources, follows the newer standard for the holidays library and should not be changed to put legal sources first.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: holidays/countries/south_africa.py:69-75
Timestamp: 2025-09-14T07:26:25.431Z
Learning: When reviewing historical holiday implementations in the vacanza/holidays repository, trust the maintainers' research and implementation decisions for specific historical edge cases, especially when they can provide sources like Wikipedia or other historical documentation that supports unusual or complex date calculation rules during specific time periods.

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 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: PPsyrius
PR: vacanza/holidays#2942
File: holidays/countries/south_africa.py:91-98
Timestamp: 2025-09-18T07:01:12.236Z
Learning: In the holidays library South Africa implementation, inline ternary operators for holiday name selection (like "Republic Day" if self._year >= 1961 else "Union Day") are intentionally kept inline rather than extracted to separate variables, as this structure is designed in preparation for future localization (l10n) support where the contextual relationship between conditions and translatable strings needs to be preserved.

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#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#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: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#2881
File: tests/countries/test_iran.py:28-28
Timestamp: 2025-09-14T16:05:55.205Z
Learning: In tests/countries/test_iran.py, using years=(self.start_year - 1, 2102) in the no-holiday test is intentional because Iran uses the Persian Calendar which has specific supported year range constraints, and 2102 represents the upper limit of the Persian Calendar's supported range, not just an arbitrary far-future date.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: When adding a new country in vacanza/holidays, also re-export it in holidays/countries/__init__.py (e.g., from .liberia import Liberia, LR, LBR) so tests and users can import from holidays.countries consistently.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: In holidays/countries/__init__.py, re-export country classes using absolute imports (e.g., 'from holidays.countries.liberia import Liberia, LR, LBR') and keep alphabetical ordering (e.g., Lesotho, Liberia, Libya). Avoid relative imports in this file.

Learnt from: KJhellico
PR: vacanza/holidays#2820
File: holidays/countries/__init__.py:199-203
Timestamp: 2025-08-31T19:34:20.731Z
Learning: In Saint Helena, Ascension and Tristan da Cunha holidays implementation (holidays/countries/saint_helena_ascension_and_tristan_da_cunha.py), only three classes are defined: SaintHelenaAscensionAndTristanDaCunha (main class), SH (alias), and SHN (alias). There is no HolidaysSH class, despite it being referenced in the registry.py entry.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: In holidays/countries/__init__.py, re-export country classes using absolute imports (e.g., 'from holidays.countries.liberia import Liberia, LR, LBR') and keep alphabetical ordering (e.g., Lesotho, Liberia, Libya). Avoid relative imports in this file.

Learnt from: KJhellico
PR: vacanza/holidays#2820
File: holidays/countries/__init__.py:199-203
Timestamp: 2025-08-31T19:34:20.731Z
Learning: In Saint Helena, Ascension and Tristan da Cunha holidays implementation (holidays/countries/saint_helena_ascension_and_tristan_da_cunha.py), only three classes are defined: SaintHelenaAscensionAndTristanDaCunha (main class), SH (alias), and SHN (alias). There is no HolidaysSH class, despite it being referenced in the registry.py entry.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: When adding a new country in vacanza/holidays, also re-export it in holidays/countries/__init__.py (e.g., from .liberia import Liberia, LR, LBR) so tests and users can import from holidays.countries consistently.

Learnt from: KJhellico
PR: vacanza/holidays#2437
File: holidays/countries/bhutan.py:27-30
Timestamp: 2025-04-08T14:46:10.656Z
Learning: For country classes in the holidays library, there's no need to explicitly specify `supported_categories = (PUBLIC,)` when PUBLIC is the only category being used, as it's already the default category inherited from HolidayBase.

Learnt from: KJhellico
PR: vacanza/holidays#2525
File: holidays/countries/togo.py:0-0
Timestamp: 2025-05-04T10:29:46.780Z
Learning: When a country class in the holidays library uses additional categories beyond PUBLIC, the `supported_categories` tuple should contain all categories, including PUBLIC. Only when PUBLIC is the only category being used should it be omitted from `supported_categories`.

Learnt from: KJhellico
PR: vacanza/holidays#2854
File: tests/countries/test_sudan.py:29-31
Timestamp: 2025-09-12T21:37:10.710Z
Learning: For countries in the holidays library that only use the default PUBLIC category (like Sudan), there's no need to specify `categories=Sudan.supported_categories` in test_no_holidays methods, as it would be equivalent to the default behavior.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_antigua_and_barbuda.py:27-29
Timestamp: 2025-09-14T16:19:23.651Z
Learning: For Antigua and Barbuda in the holidays library, only the default PUBLIC category is used, so there's no need to specify `categories=AntiguaAndBarbuda.supported_categories` in test_no_holidays methods, as it would be equivalent to the default behavior and AntiguaAndBarbuda doesn't define supported_categories.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_bolivia.py:29-29
Timestamp: 2025-09-19T10:01:41.205Z
Learning: For Bolivia in the holidays library, only the default PUBLIC category is used, so there's no need to specify `categories=Bolivia.supported_categories` in test_no_holidays methods, as it would be equivalent to the default behavior and Bolivia doesn't define supported_categories.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_djibouti.py:27-29
Timestamp: 2025-09-14T16:10:02.766Z
Learning: For Djibouti in the holidays library, only the default PUBLIC category is used, so there's no need to specify `categories=Djibouti.supported_categories` in test_no_holidays methods, as it would be equivalent to the default behavior and Djibouti doesn't define supported_categories.

Learnt from: PPsyrius
PR: vacanza/holidays#2794
File: holidays/groups/international.py:0-0
Timestamp: 2025-08-12T17:39:49.804Z
Learning: Ethiopian New Year (Enkutatash) calculation uses `is_ethiopian_leap_year(self._year)` instead of `isleap(self._year + 1)` to properly handle century edge cases. Ethiopian leap years follow Julian rules (every 4 years without exception) while Gregorian leap years have century exceptions, causing different results around years like 2100.

Learnt from: PPsyrius
PR: vacanza/holidays#2794
File: holidays/groups/international.py:0-0
Timestamp: 2025-08-12T17:39:49.804Z
Learning: Ethiopian New Year (Enkutatash) calculation correctly uses `is_ethiopian_leap_year(self._year)` instead of `isleap(self._year + 1)` to properly handle century edge cases. The Ethiopian function `(year + 1) % 4 == 0` checks if the next year is divisible by 4 using Julian/Ethiopian rules (no century exceptions), while `isleap()` applies Gregorian century rules. This difference is crucial around years like 2100 where the two calendar systems diverge.

Learnt from: PPsyrius
PR: vacanza/holidays#2489
File: holidays/countries/sao_tome_and_principe.py:86-88
Timestamp: 2025-04-23T09:22:41.753Z
Learning: For holiday definitions in the holidays package, keep comments simple with just the holiday name (e.g., "# Independence Day.") rather than including dates or historical context, as the function names already encode the date information.

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: PPsyrius
PR: vacanza/holidays#2831
File: holidays/countries/south_sudan.py:21-30
Timestamp: 2025-08-25T10:51:08.068Z
Learning: In the holidays library, references in country/market holiday implementations should be ordered as follows: Wikipedia links for the country/market holidays first, then country-specific official sources for newer implementations, then Wikipedia links for each individual non-standard holiday if any are required. Official government sources should not be placed first ahead of Wikipedia links.

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, multiple holidays on the same date are sorted alphabetically internally, so the order in which holidays are added does not affect the resulting holiday name string when multiple holidays occur on the same date.

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#2928
File: holidays/countries/algeria.py:16-22
Timestamp: 2025-09-16T04:11:33.513Z
Learning: In the holidays library, country class base inheritance follows alphabetical ordering after HolidayBase. For example, Algeria correctly uses: HolidayBase, ChristianHolidays, HebrewCalendarHolidays, InternationalHolidays, IslamicHolidays (alphabetical after the required HolidayBase first position).

Learnt from: PPsyrius
PR: vacanza/holidays#2537
File: tests/countries/test_finland.py:23-26
Timestamp: 2025-05-09T18:36:09.607Z
Learning: The holidays project prioritizes complete historical coverage in tests, verifying holidays from their first year of observance (e.g., 1853 for Finland) through future projections, rather than using shorter sliding windows.

Learnt from: PPsyrius
PR: vacanza/holidays#2874
File: holidays/countries/nigeria.py:31-44
Timestamp: 2025-08-30T22:55:34.525Z
Learning: For Nigeria holiday implementation reference ordering: The current ordering with Wikipedia first, followed by official sources, follows the newer standard for the holidays library and should not be changed to put legal sources first.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: holidays/countries/south_africa.py:69-75
Timestamp: 2025-09-14T07:26:25.431Z
Learning: When reviewing historical holiday implementations in the vacanza/holidays repository, trust the maintainers' research and implementation decisions for specific historical edge cases, especially when they can provide sources like Wikipedia or other historical documentation that supports unusual or complex date calculation rules during specific time periods.

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 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: PPsyrius
PR: vacanza/holidays#2942
File: holidays/countries/south_africa.py:91-98
Timestamp: 2025-09-18T07:01:12.236Z
Learning: In the holidays library South Africa implementation, inline ternary operators for holiday name selection (like "Republic Day" if self._year >= 1961 else "Union Day") are intentionally kept inline rather than extracted to separate variables, as this structure is designed in preparation for future localization (l10n) support where the contextual relationship between conditions and translatable strings needs to be preserved.

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#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#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: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#2881
File: tests/countries/test_iran.py:28-28
Timestamp: 2025-09-14T16:05:55.205Z
Learning: In tests/countries/test_iran.py, using years=(self.start_year - 1, 2102) in the no-holiday test is intentional because Iran uses the Persian Calendar which has specific supported year range constraints, and 2102 represents the upper limit of the Persian Calendar's supported range, not just an arbitrary far-future date.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_belgium.py:28-30
Timestamp: 2025-09-20T12:21:50.877Z
Learning: Belgium holidays implementation currently lacks a start_year attribute. In tests/countries/test_belgium.py, do not suggest adding test_no_holidays methods that rely on start_year until the start_year attribute is introduced to Belgium's holiday implementation.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: When adding a new country in vacanza/holidays, also re-export it in holidays/countries/__init__.py (e.g., from .liberia import Liberia, LR, LBR) so tests and users can import from holidays.countries consistently.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: In holidays/countries/__init__.py, re-export country classes using absolute imports (e.g., 'from holidays.countries.liberia import Liberia, LR, LBR') and keep alphabetical ordering (e.g., Lesotho, Liberia, Libya). Avoid relative imports in this file.

Learnt from: KJhellico
PR: vacanza/holidays#2820
File: holidays/countries/__init__.py:199-203
Timestamp: 2025-08-31T19:34:20.731Z
Learning: In Saint Helena, Ascension and Tristan da Cunha holidays implementation (holidays/countries/saint_helena_ascension_and_tristan_da_cunha.py), only three classes are defined: SaintHelenaAscensionAndTristanDaCunha (main class), SH (alias), and SHN (alias). There is no HolidaysSH class, despite it being referenced in the registry.py entry.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:85-86
Timestamp: 2025-04-05T04:29:38.042Z
Learning: For testing holiday implementations in the vacanza/holidays repository, recommend using `from tests.common import CommonCountryTests` as the base class instead of directly using `unittest.TestCase` to maintain consistency with project conventions and leverage common test utilities.

Learnt from: PPsyrius
PR: vacanza/holidays#2615
File: tests/countries/test_anguilla.py:1-12
Timestamp: 2025-06-16T15:48:48.680Z
Learning: Test files in the holidays repository follow a standardized structure without module or class docstrings. All country test files use the same pattern: license header, imports, and class definition (`class Test{Country}(CommonCountryTests, TestCase):`) without docstrings. This is an established codebase convention that should be maintained for consistency.

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#2833
File: tests/countries/test_uganda.py:15-0
Timestamp: 2025-08-20T19:46:15.625Z
Learning: In the holidays project, the standard import pattern for country test files is `from holidays.countries.<country> import Country, CODE1, CODE2` (direct module import), used by ~75% of country test files. Only a minority (~25%) use the aggregated public API import `from holidays.countries import Country, CODE1, CODE2`. The direct module import pattern should be used for new country test files to follow the established convention.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_saint_helena_ascension_and_tristan_da_cunha.py:209-209
Timestamp: 2025-09-14T17:17:14.387Z
Learning: In tests/countries/test_saint_helena_ascension_and_tristan_da_cunha.py, the explicit loop iteration pattern for subdivision-specific holiday checks (like Anniversary Day for TA subdivision) is intentionally preferred over using assertSubdivTa helper methods, as confirmed by PPsyrius.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_algeria.py:28-30
Timestamp: 2025-09-18T03:19:23.722Z
Learning: In the vacanza/holidays project, tests now use self.start_year and self.end_year from the TestCase class instead of country-specific aliases (like DZ.start_year) for start_year and end_year references. This approach provides the test framework with better control over test year ranges rather than being tied to specific country start years.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: When adding a new country in vacanza/holidays, also re-export it in holidays/countries/__init__.py (e.g., from .liberia import Liberia, LR, LBR) so tests and users can import from holidays.countries consistently.

Learnt from: PPsyrius
PR: vacanza/holidays#2416
File: tests/countries/test_turkmenistan.py:31-49
Timestamp: 2025-04-05T04:50:40.752Z
Learning: For Turkmenistan holiday tests, use this class structure: `class TestTurkmenistan(CommonCountryTests, TestCase)` with imports `from unittest import TestCase`, `from holidays.countries import Turkmenistan, TM, TKM`, and `from tests.common import CommonCountryTests`. Ensure to call `super().setUp()` in the setUp method.

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: KJhellico
PR: vacanza/holidays#2778
File: tests/countries/test_kiribati.py:15-15
Timestamp: 2025-08-09T18:31:23.218Z
Learning: In the holidays project test files, the standard import pattern is `from holidays.countries.<country> import Country, CODE1, CODE2` (used in ~97% of test files), not `from holidays.countries import Country, CODE1, CODE2`. Only a few exceptions (Suriname, Sierra Leone, Mauritius, Mali, Ivory Coast, Guyana) use the aggregated import pattern.

Learnt from: KJhellico
PR: vacanza/holidays#2774
File: tests/countries/test_liberia.py:15-16
Timestamp: 2025-08-08T14:37:03.045Z
Learning: In holidays/countries/__init__.py, re-export country classes using absolute imports (e.g., 'from holidays.countries.liberia import Liberia, LR, LBR') and keep alphabetical ordering (e.g., Lesotho, Liberia, Libya). Avoid relative imports in this file.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2852
File: tests/countries/test_tajikistan.py:26-28
Timestamp: 2025-08-24T13:01:51.370Z
Learning: In the holidays project country test files, the standard method name for testing country aliases (ISO codes) is `test_country_aliases`, not `test_aliases`. This naming convention is consistently used across all country test files.

Learnt from: Wasif-Shahzad
PR: vacanza/holidays#2852
File: tests/countries/test_tajikistan.py:26-28
Timestamp: 2025-08-24T13:01:51.370Z
Learning: In the holidays project country test files, the universally adopted standard method name for testing country aliases (ISO codes) is `test_country_aliases`. This naming convention is used consistently across all 235+ country test files in the repository, with no exceptions using `test_aliases`.

Learnt from: KJhellico
PR: vacanza/holidays#2623
File: tests/countries/test_christmas_island.py:136-146
Timestamp: 2025-07-09T21:16:35.145Z
Learning: In Christmas Island's holiday implementation, the test_christmas_day method cannot use assertNoNonObservedHoliday because in some years observed Christmas Day overlaps with Boxing Day when both holidays are moved due to weekend conflicts, causing the standard non-observed holiday check to fail inappropriately.

Learnt from: PPsyrius
PR: vacanza/holidays#2386
File: tests/countries/test_nepal.py:499-536
Timestamp: 2025-04-05T06:49:06.217Z
Learning: In the holidays project, test files follow a dual testing approach: individual methods test specific holidays across multiple years, while comprehensive year-specific tests (e.g., `test_2025`) verify all holidays for a specific year in a single assertion. Both approaches serve different testing purposes and complement each other.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_paraguay.py:134-139
Timestamp: 2025-09-17T09:07:56.459Z
Learning: In the vacanza/holidays project, when testing holidays that start from a specific year (not the country's start_year), the standard pattern is to use `range(specific_year, self.end_year)` for the holiday dates and `assertNoHolidayName(name, range(self.start_year, specific_year))` for the gap period. Using `self.full_range` with year conditions like `if year >= specific_year` is not the established pattern and would be inconsistent with the codebase.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_belgium.py:28-30
Timestamp: 2025-09-20T12:21:50.877Z
Learning: Belgium holidays implementation currently lacks a start_year attribute. In tests/countries/test_belgium.py, do not suggest adding test_no_holidays methods that rely on start_year until the start_year attribute is introduced to Belgium's holiday implementation.

Learnt from: PPsyrius
PR: vacanza/holidays#2750
File: tests/countries/test_germany.py:46-46
Timestamp: 2025-07-24T15:21:31.632Z
Learning: In the holidays project test files, the standard method name for testing the absence of holidays is `test_no_holidays`, not more descriptive names like `test_no_holidays_before_1990`. This is a consistent naming convention across country test files like France and Germany.

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#2881
File: tests/countries/test_barbados.py:21-23
Timestamp: 2025-09-14T16:03:13.558Z
Learning: In tests/countries/test_barbados.py, using years_non_observed=range(2000, 2024) is intentional because all observed holiday examples fall within 2001-2023, making this range appropriate for limiting testing to years where observed holidays actually exist in the test data.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_iran.py:28-28
Timestamp: 2025-09-14T16:05:55.205Z
Learning: In tests/countries/test_iran.py, using years=(self.start_year - 1, 2102) in the no-holiday test is intentional because Iran uses the Persian Calendar which has specific supported year range constraints, and 2102 represents the upper limit of the Persian Calendar's supported range, not just an arbitrary far-future date.

Learnt from: PPsyrius
PR: vacanza/holidays#2629
File: tests/countries/test_namibia.py:22-23
Timestamp: 2025-06-14T10:58:43.636Z
Learning: In the vacanza/holidays project, country test files consistently use range(start_year, 2050) which intentionally excludes 2050 and stops at 2049. This is a library-wide implementation pattern, not an off-by-one error.

Learnt from: PPsyrius
PR: vacanza/holidays#2794
File: holidays/groups/international.py:0-0
Timestamp: 2025-08-12T17:39:49.804Z
Learning: Ethiopian New Year (Enkutatash) calculation correctly uses `is_ethiopian_leap_year(self._year)` instead of `isleap(self._year + 1)` to properly handle century edge cases. The Ethiopian function `(year + 1) % 4 == 0` checks if the next year is divisible by 4 using Julian/Ethiopian rules (no century exceptions), while `isleap()` applies Gregorian century rules. This difference is crucial around years like 2100 where the two calendar systems diverge.

Learnt from: PPsyrius
PR: vacanza/holidays#2794
File: holidays/countries/ethiopia.py:63-63
Timestamp: 2025-08-12T18:40:16.160Z
Learning: Ethiopian Epiphany (Timkat) date calculation correctly uses `is_ethiopian_leap_year(self._year - 1)` in the `_add_epiphany_day` helper in `holidays/groups/christian.py`. Since Epiphany occurs in January and belongs to the Ethiopian year that started in the previous Gregorian year, it checks Ethiopian leap year rules for `self._year - 1`. This is the proper approach, not using Gregorian leap year rules.

Learnt from: PPsyrius
PR: vacanza/holidays#2881
File: tests/countries/test_south_africa.py:22-22
Timestamp: 2025-09-14T04:41:10.139Z
Learning: South Africa's observed holiday system only started in 1995, so in tests/countries/test_south_africa.py, using years_non_observed=range(1995, 2050) is intentional to limit testing to years where observed holidays actually exist, improving both correctness and performance.

Learnt from: PPsyrius
PR: vacanza/holidays#2794
File: tests/calendars/test_julian.py:35-36
Timestamp: 2025-08-12T17:16:54.497Z
Learning: In the vacanza/holidays project calendar tests (Thai, Ethiopian, Julian, etc.), the established testing pattern for validation methods is to use simple for loops like `for year in known_data_dict:` followed by `self.assertEqual(expected, actual)` without using unittest's subTest feature. This pattern is consistently maintained across all calendar test files.