23.1.0

Highlights

A lot of features and smaller bug fixes! But also with a heavy heart, we're leaving the last dataclass-less Python version (3.6) behind, but don't worry: the old versions aren't going anywhere and thanks to the magic of package metadata, pip install attrs should still work on Python 3.6 as if nothing happened.

Special Thanks

This release would not be possible without my generous sponsors! Thank you to all of you making sustainable maintenance possible! If you would like to join them, go to https://github.com/sponsors/hynek and check out the sweet perks!

Above and Beyond

Variomedia AG (@variomedia), Tidelift (@tidelift), Sentry (@getsentry), HiredScore (@HiredScore), FilePreviews (@filepreviews), and Daniel Fortunov (@asqui).

Maintenance Sustainers

Adam Hill (@adamghill), Dan Groshev (@si14), Magnus Watn (@magnuswatn), David Cramer (@dcramer), Moving Content AG (@moving-content), Stein Magnus Jodal (@jodal), ProteinQure (@ProteinQure), Jesse Snyder (@jessesnyder), Rivo Laks (@rivol), Tom Ballinger (@thomasballinger), @medecau, Ionel Cristian Mărieș (@ionelmc), The Westervelt Company (@westerveltco), Philippe Galvan (@PhilippeGalvan), Birk Jernström (@birkjernstrom), Tim Schilling (@tim-schilling), Chris Withers (@cjw296), Christopher Dignam (@chdsbd), and Stefan Hagen (@sthagen).

Not to forget 3 more amazing humans who chose to be generous but anonymous!

Full Changelog

Backwards-incompatible Changes

• Python 3.6 has been dropped and packaging switched to static package data using Hatch. #993

Deprecations

• The support for zope-interface via the attrs.validators.provides validator is now deprecated and will be removed in, or after, April 2024.

  The presence of a C-based package in our developement dependencies has caused headaches and we're not under the impression it's used a lot.

  Let us know if you're using it and we might publish it as a separate package. #1120

Changes

• attrs.filters.exclude() and attrs.filters.include() now support the passing of attribute names as strings. #1068

• attrs.has() and attrs.fields() now handle generic classes correctly. #1079

• Fix frozen exception classes when raised within e.g. contextlib.contextmanager, which mutates their __traceback__ attributes. #1081

• @frozen now works with type checkers that implement PEP-681 (ex. pyright). #1084

• Restored ability to unpickle instances pickled before 22.2.0. #1085

• attrs.asdict()'s and attrs.astuple()'s type stubs now accept the attrs.AttrsInstance protocol. #1090

• Fix slots class cellvar updating closure in CPython 3.8+ even when __code__ introspection is unavailable. #1092

• attrs.resolve_types() can now pass include_extras to typing.get_type_hints() on Python 3.9+, and does so by default. #1099

• Added instructions for pull request workflow to CONTRIBUTING.md. #1105

• Added type parameter to attrs.field() function for use with attrs.make_class().

  Please note that type checkers ignore type metadata passed into make_class(), but it can be useful if you're wrapping attrs. #1107

• It is now possible for attrs.evolve() (and attr.evolve()) to change fields named inst if the instance is passed as a positional argument.

  Passing the instance using the inst keyword argument is now deprecated and will be removed in, or after, April 2024. #1117

• attrs.validators.optional() now also accepts a tuple of validators (in addition to lists of validators). #1122