Packaging

~~~~~~~~~~~~~~~~~

* PEP 639: Implement License-Expression and License-File (:issue:`828`)
* Use ``!r`` formatter for error messages with filenames (:issue:`844`)
* Add support for PEP 730 iOS tags (:issue:`832`)
* Fix prerelease detection for ``>`` and ``<`` (:issue:`794`)
* Fix uninformative error message (:issue:`830`)
* Refactor ``canonicalize_version`` (:issue:`793`)
* Patch python_full_version unconditionally (:issue:`825`)
* Fix doc for ``canonicalize_version`` to mention ``strip_trailing_zero`` and a typo in a docstring (:issue:`801`)
* Fix typo in Version ``__str__`` (:issue:`817`)
* Support creating a ``SpecifierSet`` from an iterable of ``Specifier`` objects (:issue:`775`)

~~~~~~~~~~~~~~~~~

* Document ``markers.default_environment()`` (:issue:`753`).
* Add support for Python 3.13 (:issue:`783`).
* Modernise type annotations (:issue:`785`).
* Work around ``platform.python_version()`` returning non PEP 440 compliant version
for non-tagged CPython builds (:issue:`802`).

~~~~~~~~~~~~~~~~~

* Do specifier matching correctly when the specifier contains an epoch number
and has more components than the version (:issue:`683`)
* Support the experimental ``--disable-gil`` builds in packaging.tags
(:issue:`727`)
* BREAKING: Make optional ``metadata.Metadata`` attributes default to ``None`` (:issue:`733`)
* Fix errors when trying to access the ``description_content_type``, ``keywords``,
and ``requires_python`` attributes on ``metadata.Metadata`` when those values
have not been provided (:issue:`733`)
* Fix a bug preventing the use of the built in ``ExceptionGroup`` on versions of
Python that support it (:issue:`725`)

~~~~~~~~~~~~~~~~~

* Document calendar-based versioning scheme (:issue:`716`)
* Enforce that the entire marker string is parsed (:issue:`687`)
* Requirement parsing no longer automatically validates the URL (:issue:`120`)
* Canonicalize names for requirements comparison (:issue:`644`)
* Introduce ``metadata.Metadata`` (along with ``metadata.ExceptionGroup`` and ``metadata.InvalidMetadata``; :issue:`570`)
* Introduce the ``validate`` keyword parameter to ``utils.normalize_name()`` (:issue:`570`)
* Introduce ``utils.is_normalized_name()`` (:issue:`570`)
* Make ``utils.parse_sdist_filename()`` and ``utils.parse_wheel_filename()``
raise ``InvalidSdistFilename`` and ``InvalidWheelFilename``, respectively,
when the version component of the name is invalid
* Remove support for Python 3.7 (:issue:`783`)

~~~~~~~~~~~~~~~~~

* Parse raw metadata (:issue:`671`)
* Import underlying parser functions as an underscored variable (:issue:`663`)
* Improve error for local version label with unsupported operators (:issue:`675`)
* Add dedicated error for specifiers with incorrect `.*` suffix
* Replace spaces in platform names with underscores (:issue:`620`)
* Relax typing of ``_key`` on ``_BaseVersion`` (:issue:`669`)
* Handle prefix match with zeros at end of prefix correctly (:issue:`674`)

~~~~~~~~~~~~~~~~~

* Allow ``"extra"`` to be ``None`` in the marker environment (:issue:`650`)
* Refactor ``tags._generic_api`` to use ``EXT_SUFFIX`` (:issue:`607`)
* Correctly handle trailing whitespace on URL requirements (:issue:`642`)
* Fix typing for ``specifiers.BaseSpecifier.filter()`` (:issue:`643`)
* Use stable Python 3.11 in tests (:issue:`641`)
* Correctly handle non-normalised specifiers in requirements (:issue:`634`)
* Move to ``src/`` layout (:issue:`626`)
* Remove ``__about__`` file, in favour of keeping constants in ``__init__`` (:issue:`626`)