Prepare 21.3.0

Author: hynek

CHANGELOG.rst

@@ -17,16 +17,76 @@ Whenever there is a need to break compatibility, it is announced here in the cha
 
    However if you intend to build extensions on top of ``attrs`` you have to anticipate that.
 
-Changes for the upcoming release can be found in the `"changelog.d" directory <https://github.com/python-attrs/attrs/tree/main/changelog.d>`_ in our repository.
+.. towncrier release notes start
 
-..
-   Do *NOT* add changelog entries here!
+21.3.0 (2021-12-28)
+-------------------
 
-   This changelog is managed by towncrier and is compiled at release time.
+Backward-incompatible Changes
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-   See https://github.com/python-attrs/attrs/blob/main/.github/CONTRIBUTING.md#changelog for details.
+- When using ``@define``, converters are now run by default when setting an attribute on an instance -- additionally to validators.
+  I.e. the new default is ``on_setattr=[attrs.setters.convert, attrs.setters.validate]``.
+
+  This is unfortunately a breaking change, but it was an oversight, impossible to raise a ``DeprecationWarning`` about, and it's better to fix it now while the APIs are very fresh with few users.
+  `#835 <https://github.com/python-attrs/attrs/issues/835>`_,
+  `#886 <https://github.com/python-attrs/attrs/issues/886>`_
+- ``import attrs`` has finally landed!
+  As of this release, you can finally import ``attrs`` using its proper name.
+
+  Not all names from the ``attr`` namespace have been transferred; most notably ``attr.s`` and ``attr.ib`` are missing.
+  See ``attrs.define`` and ``attrs.field`` if you haven't seen our next-generation APIs yet.
+  A more elaborate explanation can be found `On The Core API Names <https://www.attrs.org/en/latest/names.html>`_
+
+  This feature is at least for one release **provisional**.
+  We don't *plan* on changing anything, but such a big change is unlikely to go perfectly on the first strike.
+
+  The API docs have been mostly updated, but it will be an ongoing effort to change everything to the new APIs.
+  Please note that we have **not** moved -- or even removed -- anything from ``attr``!
+
+  Please do report any bugs or documentation inconsistencies!
+  `#887 <https://github.com/python-attrs/attrs/issues/887>`_
+
+
+Changes
+^^^^^^^
+
+- ``attr.asdict(retain_collection_types=False)`` (default) dumps collection-esque keys as tuples.
+  `#646 <https://github.com/python-attrs/attrs/issues/646>`_,
+  `#888 <https://github.com/python-attrs/attrs/issues/888>`_
+- ``__match_args__`` are now generated to support Python 3.10's
+  `Structural Pattern Matching <https://docs.python.org/3.10/whatsnew/3.10.html#pep-634-structural-pattern-matching>`_.
+  This can be controlled by the ``match_args`` argument to the class decorators on Python 3.10 and later.
+  On older versions, it is never added and the argument is ignored.
+  `#815 <https://github.com/python-attrs/attrs/issues/815>`_
+- If the class-level *on_setattr* is set to ``attrs.setters.validate`` (default in ``@define`` and ``@mutable``) but no field defines a validator, pretend that it's not set.
+  `#817 <https://github.com/python-attrs/attrs/issues/817>`_
+- The generated ``__repr__`` is significantly faster on Pythons with f-strings.
+  `#819 <https://github.com/python-attrs/attrs/issues/819>`_
+- Attributes transformed via ``field_transformer`` are wrapped with ``AttrsClass`` again.
+  `#824 <https://github.com/python-attrs/attrs/issues/824>`_
+- Generated source code is now cached more efficiently for identical classes.
+  `#828 <https://github.com/python-attrs/attrs/issues/828>`_
+- Added ``attrs.converters.to_bool()``.
+  `#830 <https://github.com/python-attrs/attrs/issues/830>`_
+- ``attrs.resolve_types()`` now resolves types of subclasses after the parents are resolved.
+  `#842 <https://github.com/python-attrs/attrs/issues/842>`_
+  `#843 <https://github.com/python-attrs/attrs/issues/843>`_
+- Added new validators: ``lt(val)`` (< val), ``le(va)`` (≤ val), ``ge(val)`` (≥ val), ``gt(val)`` (> val), and ``maxlen(n)``.
+  `#845 <https://github.com/python-attrs/attrs/issues/845>`_
+- ``attrs`` classes are now fully compatible with `cloudpickle <https://github.com/cloudpipe/cloudpickle>`_ (no need to disable ``repr`` anymore).
+  `#857 <https://github.com/python-attrs/attrs/issues/857>`_
+- Added new context manager ``attrs.validators.disabled()`` and functions ``attrs.validators.(set|get)_disabled()``.
+  They deprecate ``attrs.(set|get)_run_validators()``.
+  All functions are interoperable and modify the same internal state.
+  They are not – and never were – thread-safe, though.
+  `#859 <https://github.com/python-attrs/attrs/issues/859>`_
+- ``attrs.validators.matches_re()`` now accepts pre-compiled regular expressions in addition to pattern strings.
+  `#877 <https://github.com/python-attrs/attrs/issues/877>`_
+
+
+----
 
-.. towncrier release notes start
 
 21.2.0 (2021-05-07)
 -------------------

changelog.d/646.change.rst

@@ -24,7 +24,7 @@
 from ._version_info import VersionInfo
 
 
-__version__ = "21.3.0.dev0"
+__version__ = "21.3.0"
 __version_info__ = VersionInfo._from_version_string(__version__)
 
 __title__ = "attrs"