- **Potentially breaking**: skip _attrs_ fields marked as `init=False` by default. This change is potentially breaking for unstructuring.
See [here](https://catt.rs/en/latest/customizing.html#include_init_false) for instructions on how to restore the old behavior.
([40](https://github.com/python-attrs/cattrs/issues/40) [#395](https://github.com/python-attrs/cattrs/pull/395))
- **Potentially breaking**: {py:func}`cattrs.gen.make_dict_structure_fn` and {py:func}`cattrs.gen.typeddicts.make_dict_structure_fn` will use the values for the `detailed_validation` and `forbid_extra_keys` parameters from the given converter by default now.
If you're using these functions directly, the old behavior can be restored by passing in the desired values directly.
([410](https://github.com/python-attrs/cattrs/issues/410) [#411](https://github.com/python-attrs/cattrs/pull/411))
- **Potentially breaking**: The default union structuring strategy will also use fields annotated as `typing.Literal` to help guide structuring.
See [here](https://catt.rs/en/latest/unions.html#default-union-strategy) for instructions on how to restore the old behavior.
([391](https://github.com/python-attrs/cattrs/pull/391))
- Python 3.12 is now supported. Python 3.7 is no longer supported; use older releases there.
([424](https://github.com/python-attrs/cattrs/pull/424))
- Implement the `union passthrough` strategy, enabling much richer union handling for preconfigured converters. [Learn more here](https://catt.rs/en/stable/strategies.html#union-passthrough).
- Introduce the `use_class_methods` strategy. Learn more [here](https://catt.rs/en/latest/strategies.html#using-class-specific-structure-and-unstructure-methods).
([405](https://github.com/python-attrs/cattrs/pull/405))
- The `omit` parameter of {py:func}`cattrs.override` is now of type `bool | None` (from `bool`).
`None` is the new default and means to apply default _cattrs_ handling to the attribute, which is to omit the attribute if it's marked as `init=False`, and keep it otherwise.
- Converters can now be initialized with [custom fallback hook factories](https://catt.rs/en/latest/converters.html#fallback-hook-factories) for un/structuring.
([331](https://github.com/python-attrs/cattrs/issues/311) [#441](https://github.com/python-attrs/cattrs/pull/441))
- Add support for `date` to preconfigured converters.
([420](https://github.com/python-attrs/cattrs/pull/420))
- Add support for `datetime.date`s to the PyYAML preconfigured converter.
([393](https://github.com/python-attrs/cattrs/issues/393))
- Fix {py:func}`format_exception() <cattrs.v.format_exception>` parameter working for recursive calls to {py:func}`transform_error <cattrs.transform_error>`.
([389](https://github.com/python-attrs/cattrs/issues/389))
- [_attrs_ aliases](https://www.attrs.org/en/stable/init.html#private-attributes-and-aliases) are now supported, although aliased fields still map to their attribute name instead of their alias by default when un/structuring.
([322](https://github.com/python-attrs/cattrs/issues/322) [#391](https://github.com/python-attrs/cattrs/pull/391))
- Fix TypedDicts with periods in their field names.
([376](https://github.com/python-attrs/cattrs/issues/376) [#377](https://github.com/python-attrs/cattrs/pull/377))
- Optimize and improve unstructuring of `Optional` (unions of one type and `None`).
([380](https://github.com/python-attrs/cattrs/issues/380) [#381](https://github.com/python-attrs/cattrs/pull/381))
- Fix {py:func}`format_exception <cattrs.v.format_exception>` and {py:func}`transform_error <cattrs.transform_error>` type annotations.
- Improve the implementation of `cattrs._compat.is_typeddict`. The implementation is now simpler, and relies on fewer private implementation details from `typing` and typing_extensions.
([384](https://github.com/python-attrs/cattrs/pull/384))
- Improve handling of TypedDicts with forward references.
- Speed up generated _attrs_ and TypedDict structuring functions by changing their signature slightly.
([388](https://github.com/python-attrs/cattrs/pull/388))
- Fix copying of converters with function hooks.
([398](https://github.com/python-attrs/cattrs/issues/398) [#399](https://github.com/python-attrs/cattrs/pull/399))
- Broaden {py:func}`loads' <cattrs.preconf.orjson.OrjsonConverter.loads>` type definition for the preconf orjson converter.
([400](https://github.com/python-attrs/cattrs/pull/400))
- {py:class}`AttributeValidationNote <cattrs.AttributeValidationNote>` and {py:class}`IterableValidationNote <cattrs.IterableValidationNote>` are now picklable.
([408](https://github.com/python-attrs/cattrs/pull/408))
- Fix structuring `Final` lists.
([412](https://github.com/python-attrs/cattrs/issues/412))
- Fix certain cases of structuring `Annotated` types.
([418](https://github.com/python-attrs/cattrs/issues/418))
- Fix the [tagged union strategy](https://catt.rs/en/stable/strategies.html#tagged-unions-strategy) to work with `forbid_extra_keys`.
([402](https://github.com/python-attrs/cattrs/issues/402) [#443](https://github.com/python-attrs/cattrs/pull/443))
- Use [PDM](https://pdm.fming.dev/latest/) instead of Poetry.
- _cattrs_ is now linted with [Ruff](https://beta.ruff.rs/docs/).
- Remove some unused lines in the unstructuring code.
([416](https://github.com/python-attrs/cattrs/pull/416))
- Fix handling classes inheriting from non-generic protocols.
([374](https://github.com/python-attrs/cattrs/issues/374) [#436](https://github.com/python-attrs/cattrs/pull/436))
- The documentation Makefile now supports the `htmlview` and `htmllive` targets. ([442](https://github.com/python-attrs/cattrs/pull/442))
- _cattrs_ is now published using PyPI Trusted Publishers, and `main` branch commits are automatically deployed to Test PyPI.