Introduce holiday categories support

[KJhellico]

Proposed change

Currently, Python Holidays supports only main country holidays ("state holidays", or "federal holidays", or "paid holidays" etc). But many countries have other categories of holidays: bank holidays, school holidays, additional (paid or non-paid) holidays, religious holidays (valid only for these religions followers). So this PR introduce initial holiday categories support.

Set of existing holidays matches "PUBLIC" category (that is populated by default, if categories value is not specified).

For example:

>>> from holidays import country_holidays
>>> from holidays.categories import BANK, PUBLIC
>>> at = country_holidays("AT")  # "common" holidays as default
>>> "2023-12-31" in at
False
>>> at_full = country_holidays("AT", categories=(BANK, PUBLIC))
>>> "2023-12-31" in at_full
True
>>> at_full["2023-12-31"]
Silvester

Type of change

• New country/market holidays support (thank you!)
• Supported country/market holidays update (calendar discrepancy fix, localization)
• Existing code/documentation/test/process quality improvement (best practice, cleanup, refactoring, optimization)
• Dependency upgrade (version update)
• Bugfix (non-breaking change which fixes an issue)
• Breaking change (a code change causing existing functionality to break)
• New feature (new python-holidays functionality in general)

Checklist

• I've followed the contributing guidelines
• This PR is filed against beta branch of the repository
• This PR doesn't contain any merge conflicts and has clean commit history
• The code style looks good: make pre-commit
• All tests pass locally: make test, make tox (we strongly encourage adding tests to your code)
• The related documentation has been added/updated (check off the box for free if no updates is required)

[coveralls]

coverage: 100.0%. remained the same when pulling ce955be on KJhellico:feat-holiday-categories into ddf111e on dr-prodigy:beta.

[PPsyrius]

Good work IMO, although I got some questions here:

Should half-day holidays i.e. #784 or Curacao's New Year's Eve holiday (see in-code comment in #1309), be included in this PR or is it considered an entirely-different feature altogether?

For religious holidays another good example might be Argentina where Muslim and Jewish citizens got extra holidays on top of mainstream Christian ones, as well as an additional holidays that apply to citizens of Armenian origin only.

[KJhellico]

Should half-day holidays i.e. #784 or Curacao's New Year's Eve holiday (see in-code comment in #1309), be included in this PR or is it considered an entirely-different feature altogether?

Yes, I think such holidays can be added as "half-day" category (or something like). Maybe with (or without) some additional label...

For religious holidays another good example might be Argentina where Muslim and Jewish citizens got extra holidays on top of mainstream Christian ones, as well as an additional holidays that apply to citizens of Armenian origin only.

These are exactly the cases I meant!

[arkid15r]

This PoC looks great!

Besides the naming suggestions below I'd also like you to address category support check, i.e. raise NotImplementedError (duh) for cases when a requested category isn't supported.

[arkid15r]

👍

Just one more idea for improvement:

[KJhellico]

Besides the naming suggestions below I'd also like you to address category support check, i.e. raise NotImplementedError (duh) for cases when a requested category isn't supported.

It's worth to think about it. 👍

[KJhellico]

But then we need to switch all countries at once to support categories. In order to have supported_categories = ("public",) everywhere.

[arkid15r]

Some suggestions:

[arkid15r]

LGTM

[PPsyrius]

@KJhellico Hi, I'm working on extending the testcases right now for Thailand Holidays categories and yet it keep returning non-Bank/Government Holidays for my test results:

    def test_raeknakhwan(self):
        name = "วันพืชมงคล"
        self.assertHolidays(
            Thailand(categories={GOVERNMENT}, years=range(1997, 2024)),
            ("1997-05-13", name),
            ("1998-05-13", name),
            ("2000-05-15", name),
            ("2001-05-16", name),
            ("2002-05-09", name),
            ("2003-05-08", name),
            ("2004-05-07", name),
            ("2005-05-11", name),
            ("2006-05-11", name),
            ("2007-05-10", name),
            ("2008-05-09", name),
            ("2009-05-11", name),
            ("2010-05-10", name),
            ("2011-05-13", name),
            ("2012-05-09", name),
            ("2013-05-13", name),
            ("2014-05-09", name),
            ("2015-05-13", name),
            ("2016-05-09", name),
            ("2017-05-12", name),
            ("2018-05-14", name),
            ("2019-05-09", name),
            ("2020-05-11", name),
            ("2021-05-13", name),
            ("2022-05-17", name),
            ("2023-05-11", name),
        )

    def test_bank_holiday(self):
        a_name = "วันหยุดเพิ่มเติมสำหรับการปิดบัญชีประจำปีของธนาคารเพื่อการเกษตรและสหกรณ์การเกษตร"
        m_name = "วันหยุดภาคครึ่งปีของสถาบันการเงินและสถาบันการเงินเฉพาะกิจ"

        self.assertHolidays(
            Thailand(categories={BANK}, years=range(2012, 2023)),
            ("2012-04-01", a_name),
            ("2012-07-01", m_name),
            ("2013-04-01", a_name),
            ("2013-07-01", m_name),
            ("2014-04-01", a_name),
            ("2014-07-01", m_name),
            ("2015-04-01", a_name),
            ("2015-07-01", m_name),
            ("2016-04-01", a_name),
            ("2016-07-01", m_name),
            ("2017-04-01", a_name),
            ("2017-07-01", m_name),
            ("2018-04-01", a_name),
            ("2018-07-01", m_name),
            ("2019-04-01", a_name),
            ("2020-04-01", a_name),
            ("2021-04-01", a_name),
        )

[KJhellico]

@KJhellico Hi, I'm working on extending the testcases right now for Thailand Holidays categories and yet it keep returning non-Bank/Government Holidays for my test results:

Did you replace _populate() with _populate_public_holidays() for Thailand? (and year with self._year inside it)

[KJhellico]

I see, problem is special holidays, they are always populated :)

[PPsyrius]

I see, problem is special holidays, they are always populated :)

Oh, that explains it