- Update to 21.12.0b1:
* Fix determination of f-string expression spans (#2654)
* Fix bad formatting of error messages about EOF in multi-line statements (#2343)
* Functions and classes in blocks now have more consistent surrounding spacing (#2472)
* from __future__ import annotations statement now implies Python 3.7+ (#2690)
* Fix assignment to environment variables in Jupyter Notebooks (#2642)
* Point users to using --target-version py310 if we detect 3.10-only syntax (#2668)
* Fix match statements with open sequence subjects, like match a, b: or match a, *b: (#2639) (#2659)
* Fix match/case statements that contain match/case soft keywords multiple times, like match re.match() (#2661)
* Fix case statements with an inline body (#2665)
* Fix styling of starred expressions inside match subject (#2667)
* Fix parser error location on invalid syntax in a match statement (#2649)
* Fix Python 3.10 support on platforms without ProcessPoolExecutor (#2631)
* Improve parsing performance on code that uses match under --target-version py310 up to ~50% (#2670)
* Remove dependency on regex (#2644) (#2663)
* Warn about Python 2 deprecation in more cases by improving Python 2 only syntax detection (#2592)
* Add experimental PyPy support (#2559)
* Add partial support for the match statement. As it's experimental, it's only enabled when --target-version py310 is explicitly specified (#2586)
* Add support for parenthesized with (#2586)
* Declare support for Python 3.10 for running Black (#2562)
* Add new --workers parameter (#2514)
* Fixed feature detection for positional-only arguments in lambdas (#2532)
* Fixed a Python 3.10 compatibility issue where the loop argument was still being passed even though it has been removed (#2580)
* Deprecate Python 2 formatting support (#2523)
* Fix missing modules in self-contained binaries (#2466)
* Fix missing toml extra used during installation (#2475)
* Add support for formatting Jupyter Notebook files (#2357)
* Move from appdirs dependency to platformdirs (#2375)
* Present a more user-friendly error if .gitignore is invalid (#2414)
* Pin setuptools-scm build-time dependency version (#2457)