# Change Log ## Unreleased ### _Black_ - Fixed Python 3.10 support on platforms without ProcessPoolExecutor (#2631) ## 21.11b1 ### _Black_ - Bumped regex version minimum to 2021.4.4 to fix Pattern class usage (#2621) ## 21.11b0 ### _Black_ - 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) ### Integrations - Fixed vim plugin with Python 3.10 by removing deprecated distutils import (#2610) - The vim plugin now parses `skip_magic_trailing_comma` from pyproject.toml (#2613) ## 21.10b0 ### _Black_ - Document stability policy, that will apply for non-beta releases (#2529) - Add new `--workers` parameter (#2514) - Fixed feature detection for positional-only arguments in lambdas (#2532) - Bumped typed-ast version minimum to 1.4.3 for 3.10 compatibility (#2519) - 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) ### _Blackd_ - Remove dependency on aiohttp-cors (#2500) - Bump required aiohttp version to 3.7.4 (#2509) ### _Black-Primer_ - Add primer support for --projects (#2555) - Print primer summary after individual failures (#2570) ### Integrations - Allow to pass `target_version` in the vim plugin (#1319) - Install build tools in docker file and use multi-stage build to keep the image size down (#2582) ## 21.9b0 ### Packaging - Fix missing modules in self-contained binaries (#2466) - Fix missing toml extra used during installation (#2475) ## 21.8b0 ### _Black_ - 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) - The failsafe for accidentally added backslashes in f-string expressions has been hardened to handle more edge cases during quote normalization (#2437) - Avoid changing a function return type annotation's type to a tuple by adding a trailing comma (#2384) - Parsing support has been added for unparenthesized walruses in set literals, set comprehensions, and indices (#2447). - Pin `setuptools-scm` build-time dependency version (#2457) - Exclude typing-extensions version 3.10.0.1 due to it being broken on Python 3.10 (#2460) ### _Blackd_ - Replace sys.exit(-1) with raise ImportError as it plays more nicely with tools that scan installed packages (#2440) ### Integrations - The provided pre-commit hooks no longer specify `language_version` to avoid overriding `default_language_version` (#2430) ## 21.7b0 ### _Black_ - Configuration files using TOML features higher than spec v0.5.0 are now supported (#2301) - Add primer support and test for code piped into black via STDIN (#2315) - Fix internal error when `FORCE_OPTIONAL_PARENTHESES` feature is enabled (#2332) - Accept empty stdin (#2346) - Provide a more useful error when parsing fails during AST safety checks (#2304) ### Docker - Add new `latest_release` tag automation to follow latest black release on docker images (#2374) ### Integrations - The vim plugin now searches upwards from the directory containing the current buffer instead of the current working directory for pyproject.toml. (#1871) - The vim plugin now reads the correct string normalization option in pyproject.toml (#1869) - The vim plugin no longer crashes Black when there's boolean values in pyproject.toml (#1869) ## 21.6b0 ### _Black_ - Fix failure caused by `fmt: skip` and indentation (#2281) - Account for += assignment when deciding whether to split string (#2312) - Correct max string length calculation when there are string operators (#2292) - Fixed option usage when using the `--code` flag (#2259) - Do not call `uvloop.install()` when _Black_ is used as a library (#2303) - Added `--required-version` option to require a specific version to be running (#2300) - Fix incorrect custom breakpoint indices when string group contains fake f-strings (#2311) - Fix regression where `R` prefixes would be lowercased for docstrings (#2285) - Fix handling of named escapes (`\N{...}`) when `--experimental-string-processing` is used (#2319) ### Integrations - The official Black action now supports choosing what version to use, and supports the major 3 OSes. (#1940) ## 21.5b2 ### _Black_ - A space is no longer inserted into empty docstrings (#2249) - Fix handling of .gitignore files containing non-ASCII characters on Windows (#2229) - Respect `.gitignore` files in all levels, not only `root/.gitignore` file (apply `.gitignore` rules like `git` does) (#2225) - Restored compatibility with Click 8.0 on Python 3.6 when LANG=C used (#2227) - Add extra uvloop install + import support if in python env (#2258) - Fix --experimental-string-processing crash when matching parens are not found (#2283) - Make sure to split lines that start with a string operator (#2286) - Fix regular expression that black uses to identify f-expressions (#2287) ### _Blackd_ - Add a lower bound for the `aiohttp-cors` dependency. Only 0.4.0 or higher is supported. (#2231) ### Packaging - Release self-contained x86_64 MacOS binaries as part of the GitHub release pipeline (#2198) - Always build binaries with the latest available Python (#2260) ### Documentation - Add discussion of magic comments to FAQ page (#2272) - `--experimental-string-processing` will be enabled by default in the future (#2273) - Fix typos discovered by codespell (#2228) - Fix Vim plugin installation instructions. (#2235) - Add new Frequently Asked Questions page (#2247) - Fix encoding + symlink issues preventing proper build on Windows (#2262) ## 21.5b1 ### _Black_ - Refactor `src/black/__init__.py` into many files (#2206) ### Documentation - Replaced all remaining references to the [`master`](https://github.com/psf/black/tree/main) branch with the [`main`](https://github.com/psf/black/tree/main) branch. Some additional changes in the source code were also made. (#2210) - Sigificantly reorganized the documentation to make much more sense. Check them out by heading over to [the stable docs on RTD](https://black.readthedocs.io/en/stable/). (#2174) ## 21.5b0 ### _Black_ - Set `--pyi` mode if `--stdin-filename` ends in `.pyi` (#2169) - Stop detecting target version as Python 3.9+ with pre-PEP-614 decorators that are being called but with no arguments (#2182) ### _Black-Primer_ - Add `--no-diff` to black-primer to suppress formatting changes (#2187) ## 21.4b2 ### _Black_ - Fix crash if the user configuration directory is inaccessible. (#2158) - Clarify [circumstances](https://github.com/psf/black/blob/master/docs/the_black_code_style.md#pragmatism) in which _Black_ may change the AST (#2159) - Allow `.gitignore` rules to be overridden by specifying `exclude` in `pyproject.toml` or on the command line. (#2170) ### _Packaging_ - Install `primer.json` (used by `black-primer` by default) with black. (#2154) ## 21.4b1 ### _Black_ - Fix crash on docstrings ending with "\\ ". (#2142) - Fix crash when atypical whitespace is cleaned out of dostrings (#2120) - Reflect the `--skip-magic-trailing-comma` and `--experimental-string-processing` flags in the name of the cache file. Without this fix, changes in these flags would not take effect if the cache had already been populated. (#2131) - Don't remove necessary parentheses from assignment expression containing assert / return statements. (#2143) ### _Packaging_ - Bump pathspec to >= 0.8.1 to solve invalid .gitignore exclusion handling ## 21.4b0 ### _Black_ - Fixed a rare but annoying formatting instability created by the combination of optional trailing commas inserted by `Black` and optional parentheses looking at pre-existing "magic" trailing commas. This fixes issue #1629 and all of its many many duplicates. (#2126) - `Black` now processes one-line docstrings by stripping leading and trailing spaces, and adding a padding space when needed to break up """". (#1740) - `Black` now cleans up leading non-breaking spaces in comments (#2092) - `Black` now respects `--skip-string-normalization` when normalizing multiline docstring quotes (#1637) - `Black` no longer removes all empty lines between non-function code and decorators when formatting typing stubs. Now `Black` enforces a single empty line. (#1646) - `Black` no longer adds an incorrect space after a parenthesized assignment expression in if/while statements (#1655) - Added `--skip-magic-trailing-comma` / `-C` to avoid using trailing commas as a reason to split lines (#1824) - fixed a crash when PWD=/ on POSIX (#1631) - fixed "I/O operation on closed file" when using --diff (#1664) - Prevent coloured diff output being interleaved with multiple files (#1673) - Added support for PEP 614 relaxed decorator syntax on python 3.9 (#1711) - Added parsing support for unparenthesized tuples and yield expressions in annotated assignments (#1835) - added `--extend-exclude` argument (PR #2005) - speed up caching by avoiding pathlib (#1950) - `--diff` correctly indicates when a file doesn't end in a newline (#1662) - Added `--stdin-filename` argument to allow stdin to respect `--force-exclude` rules (#1780) - Lines ending with `fmt: skip` will now be not formatted (#1800) - PR #2053: Black no longer relies on typed-ast for Python 3.8 and higher - PR #2053: Python 2 support is now optional, install with `python3 -m pip install black[python2]` to maintain support. - Exclude `venv` directory by default (#1683) - Fixed "Black produced code that is not equivalent to the source" when formatting Python 2 docstrings (#2037) ### _Packaging_ - Self-contained native _Black_ binaries are now provided for releases via GitHub Releases (#1743) ## 20.8b1 ### _Packaging_ - explicitly depend on Click 7.1.2 or newer as `Black` no longer works with versions older than 7.0 ## 20.8b0 ### _Black_ - re-implemented support for explicit trailing commas: now it works consistently within any bracket pair, including nested structures (#1288 and duplicates) - `Black` now reindents docstrings when reindenting code around it (#1053) - `Black` now shows colored diffs (#1266) - `Black` is now packaged using 'py3' tagged wheels (#1388) - `Black` now supports Python 3.8 code, e.g. star expressions in return statements (#1121) - `Black` no longer normalizes capital R-string prefixes as those have a community-accepted meaning (#1244) - `Black` now uses exit code 2 when specified configuration file doesn't exit (#1361) - `Black` now works on AWS Lambda (#1141) - added `--force-exclude` argument (#1032) - removed deprecated `--py36` option (#1236) - fixed `--diff` output when EOF is encountered (#526) - fixed `# fmt: off` handling around decorators (#560) - fixed unstable formatting with some `# type: ignore` comments (#1113) - fixed invalid removal on organizing brackets followed by indexing (#1575) - introduced `black-primer`, a CI tool that allows us to run regression tests against existing open source users of Black (#1402) - introduced property-based fuzzing to our test suite based on Hypothesis and Hypothersmith (#1566) - implemented experimental and disabled by default long string rewrapping (#1132), hidden under a `--experimental-string-processing` flag while it's being worked on; this is an undocumented and unsupported feature, you lose Internet points for depending on it (#1609) ### Vim plugin - prefer virtualenv packages over global packages (#1383) ## 19.10b0 - added support for PEP 572 assignment expressions (#711) - added support for PEP 570 positional-only arguments (#943) - added support for async generators (#593) - added support for pre-splitting collections by putting an explicit trailing comma inside (#826) - added `black -c` as a way to format code passed from the command line (#761) - --safe now works with Python 2 code (#840) - fixed grammar selection for Python 2-specific code (#765) - fixed feature detection for trailing commas in function definitions and call sites (#763) - `# fmt: off`/`# fmt: on` comment pairs placed multiple times within the same block of code now behave correctly (#1005) - _Black_ no longer crashes on Windows machines with more than 61 cores (#838) - _Black_ no longer crashes on standalone comments prepended with a backslash (#767) - _Black_ no longer crashes on `from` ... `import` blocks with comments (#829) - _Black_ no longer crashes on Python 3.7 on some platform configurations (#494) - _Black_ no longer fails on comments in from-imports (#671) - _Black_ no longer fails when the file starts with a backslash (#922) - _Black_ no longer merges regular comments with type comments (#1027) - _Black_ no longer splits long lines that contain type comments (#997) - removed unnecessary parentheses around `yield` expressions (#834) - added parentheses around long tuples in unpacking assignments (#832) - added parentheses around complex powers when they are prefixed by a unary operator (#646) - fixed bug that led _Black_ format some code with a line length target of 1 (#762) - _Black_ no longer introduces quotes in f-string subexpressions on string boundaries (#863) - if _Black_ puts parenthesis around a single expression, it moves comments to the wrapped expression instead of after the brackets (#872) - `blackd` now returns the version of _Black_ in the response headers (#1013) - `blackd` can now output the diff of formats on source code when the `X-Diff` header is provided (#969) ## 19.3b0 - new option `--target-version` to control which Python versions _Black_-formatted code should target (#618) - deprecated `--py36` (use `--target-version=py36` instead) (#724) - _Black_ no longer normalizes numeric literals to include `_` separators (#696) - long `del` statements are now split into multiple lines (#698) - type comments are no longer mangled in function signatures - improved performance of formatting deeply nested data structures (#509) - _Black_ now properly formats multiple files in parallel on Windows (#632) - _Black_ now creates cache files atomically which allows it to be used in parallel pipelines (like `xargs -P8`) (#673) - _Black_ now correctly indents comments in files that were previously formatted with tabs (#262) - `blackd` now supports CORS (#622) ## 18.9b0 - numeric literals are now formatted by _Black_ (#452, #461, #464, #469): - numeric literals are normalized to include `_` separators on Python 3.6+ code - added `--skip-numeric-underscore-normalization` to disable the above behavior and leave numeric underscores as they were in the input - code with `_` in numeric literals is recognized as Python 3.6+ - most letters in numeric literals are lowercased (e.g., in `1e10`, `0x01`) - hexadecimal digits are always uppercased (e.g. `0xBADC0DE`) - added `blackd`, see [its documentation](https://github.com/psf/black/blob/18.9b0/README.md#blackd) for more info (#349) - adjacent string literals are now correctly split into multiple lines (#463) - trailing comma is now added to single imports that don't fit on a line (#250) - cache is now populated when `--check` is successful for a file which speeds up consecutive checks of properly formatted unmodified files (#448) - whitespace at the beginning of the file is now removed (#399) - fixed mangling [pweave](http://mpastell.com/pweave/) and [Spyder IDE](https://www.spyder-ide.org/) special comments (#532) - fixed unstable formatting when unpacking big tuples (#267) - fixed parsing of `__future__` imports with renames (#389) - fixed scope of `# fmt: off` when directly preceding `yield` and other nodes (#385) - fixed formatting of lambda expressions with default arguments (#468) - fixed `async for` statements: _Black_ no longer breaks them into separate lines (#372) - note: the Vim plugin stopped registering `,=` as a default chord as it turned out to be a bad idea (#415) ## 18.6b4 - hotfix: don't freeze when multiple comments directly precede `# fmt: off` (#371) ## 18.6b3 - typing stub files (`.pyi`) now have blank lines added after constants (#340) - `# fmt: off` and `# fmt: on` are now much more dependable: - they now work also within bracket pairs (#329) - they now correctly work across function/class boundaries (#335) - they now work when an indentation block starts with empty lines or misaligned comments (#334) - made Click not fail on invalid environments; note that Click is right but the likelihood we'll need to access non-ASCII file paths when dealing with Python source code is low (#277) - fixed improper formatting of f-strings with quotes inside interpolated expressions (#322) - fixed unnecessary slowdown when long list literals where found in a file - fixed unnecessary slowdown on AST nodes with very many siblings - fixed cannibalizing backslashes during string normalization - fixed a crash due to symbolic links pointing outside of the project directory (#338) ## 18.6b2 - added `--config` (#65) - added `-h` equivalent to `--help` (#316) - fixed improper unmodified file caching when `-S` was used - fixed extra space in string unpacking (#305) - fixed formatting of empty triple quoted strings (#313) - fixed unnecessary slowdown in comment placement calculation on lines without comments ## 18.6b1 - hotfix: don't output human-facing information on stdout (#299) - hotfix: don't output cake emoji on non-zero return code (#300) ## 18.6b0 - added `--include` and `--exclude` (#270) - added `--skip-string-normalization` (#118) - added `--verbose` (#283) - the header output in `--diff` now actually conforms to the unified diff spec - fixed long trivial assignments being wrapped in unnecessary parentheses (#273) - fixed unnecessary parentheses when a line contained multiline strings (#232) - fixed stdin handling not working correctly if an old version of Click was used (#276) - _Black_ now preserves line endings when formatting a file in place (#258) ## 18.5b1 - added `--pyi` (#249) - added `--py36` (#249) - Python grammar pickle caches are stored with the formatting caches, making _Black_ work in environments where site-packages is not user-writable (#192) - _Black_ now enforces a PEP 257 empty line after a class-level docstring (and/or fields) and the first method - fixed invalid code produced when standalone comments were present in a trailer that was omitted from line splitting on a large expression (#237) - fixed optional parentheses being removed within `# fmt: off` sections (#224) - fixed invalid code produced when stars in very long imports were incorrectly wrapped in optional parentheses (#234) - fixed unstable formatting when inline comments were moved around in a trailer that was omitted from line splitting on a large expression (#238) - fixed extra empty line between a class declaration and the first method if no class docstring or fields are present (#219) - fixed extra empty line between a function signature and an inner function or inner class (#196) ## 18.5b0 - call chains are now formatted according to the [fluent interfaces](https://en.wikipedia.org/wiki/Fluent_interface) style (#67) - data structure literals (tuples, lists, dictionaries, and sets) are now also always exploded like imports when they don't fit in a single line (#152) - slices are now formatted according to PEP 8 (#178) - parentheses are now also managed automatically on the right-hand side of assignments and return statements (#140) - math operators now use their respective priorities for delimiting multiline expressions (#148) - optional parentheses are now omitted on expressions that start or end with a bracket and only contain a single operator (#177) - empty parentheses in a class definition are now removed (#145, #180) - string prefixes are now standardized to lowercase and `u` is removed on Python 3.6+ only code and Python 2.7+ code with the `unicode_literals` future import (#188, #198, #199) - typing stub files (`.pyi`) are now formatted in a style that is consistent with PEP 484 (#207, #210) - progress when reformatting many files is now reported incrementally - fixed trailers (content with brackets) being unnecessarily exploded into their own lines after a dedented closing bracket (#119) - fixed an invalid trailing comma sometimes left in imports (#185) - fixed non-deterministic formatting when multiple pairs of removable parentheses were used (#183) - fixed multiline strings being unnecessarily wrapped in optional parentheses in long assignments (#215) - fixed not splitting long from-imports with only a single name - fixed Python 3.6+ file discovery by also looking at function calls with unpacking. This fixed non-deterministic formatting if trailing commas where used both in function signatures with stars and function calls with stars but the former would be reformatted to a single line. - fixed crash on dealing with optional parentheses (#193) - fixed "is", "is not", "in", and "not in" not considered operators for splitting purposes - fixed crash when dead symlinks where encountered ## 18.4a4 - don't populate the cache on `--check` (#175) ## 18.4a3 - added a "cache"; files already reformatted that haven't changed on disk won't be reformatted again (#109) - `--check` and `--diff` are no longer mutually exclusive (#149) - generalized star expression handling, including double stars; this fixes multiplication making expressions "unsafe" for trailing commas (#132) - _Black_ no longer enforces putting empty lines behind control flow statements (#90) - _Black_ now splits imports like "Mode 3 + trailing comma" of isort (#127) - fixed comment indentation when a standalone comment closes a block (#16, #32) - fixed standalone comments receiving extra empty lines if immediately preceding a class, def, or decorator (#56, #154) - fixed `--diff` not showing entire path (#130) - fixed parsing of complex expressions after star and double stars in function calls (#2) - fixed invalid splitting on comma in lambda arguments (#133) - fixed missing splits of ternary expressions (#141) ## 18.4a2 - fixed parsing of unaligned standalone comments (#99, #112) - fixed placement of dictionary unpacking inside dictionary literals (#111) - Vim plugin now works on Windows, too - fixed unstable formatting when encountering unnecessarily escaped quotes in a string (#120) ## 18.4a1 - added `--quiet` (#78) - added automatic parentheses management (#4) - added [pre-commit](https://pre-commit.com) integration (#103, #104) - fixed reporting on `--check` with multiple files (#101, #102) - fixed removing backslash escapes from raw strings (#100, #105) ## 18.4a0 - added `--diff` (#87) - add line breaks before all delimiters, except in cases like commas, to better comply with PEP 8 (#73) - standardize string literals to use double quotes (almost) everywhere (#75) - fixed handling of standalone comments within nested bracketed expressions; _Black_ will no longer produce super long lines or put all standalone comments at the end of the expression (#22) - fixed 18.3a4 regression: don't crash and burn on empty lines with trailing whitespace (#80) - fixed 18.3a4 regression: `# yapf: disable` usage as trailing comment would cause _Black_ to not emit the rest of the file (#95) - when CTRL+C is pressed while formatting many files, _Black_ no longer freaks out with a flurry of asyncio-related exceptions - only allow up to two empty lines on module level and only single empty lines within functions (#74) ## 18.3a4 - `# fmt: off` and `# fmt: on` are implemented (#5) - automatic detection of deprecated Python 2 forms of print statements and exec statements in the formatted file (#49) - use proper spaces for complex expressions in default values of typed function arguments (#60) - only return exit code 1 when --check is used (#50) - don't remove single trailing commas from square bracket indexing (#59) - don't omit whitespace if the previous factor leaf wasn't a math operator (#55) - omit extra space in kwarg unpacking if it's the first argument (#46) - omit extra space in [Sphinx auto-attribute comments](http://www.sphinx-doc.org/en/stable/ext/autodoc.html#directive-autoattribute) (#68) ## 18.3a3 - don't remove single empty lines outside of bracketed expressions (#19) - added ability to pipe formatting from stdin to stdin (#25) - restored ability to format code with legacy usage of `async` as a name (#20, #42) - even better handling of numpy-style array indexing (#33, again) ## 18.3a2 - changed positioning of binary operators to occur at beginning of lines instead of at the end, following [a recent change to PEP 8](https://github.com/python/peps/commit/c59c4376ad233a62ca4b3a6060c81368bd21e85b) (#21) - ignore empty bracket pairs while splitting. This avoids very weirdly looking formattings (#34, #35) - remove a trailing comma if there is a single argument to a call - if top level functions were separated by a comment, don't put four empty lines after the upper function - fixed unstable formatting of newlines with imports - fixed unintentional folding of post scriptum standalone comments into last statement if it was a simple statement (#18, #28) - fixed missing space in numpy-style array indexing (#33) - fixed spurious space after star-based unary expressions (#31) ## 18.3a1 - added `--check` - only put trailing commas in function signatures and calls if it's safe to do so. If the file is Python 3.6+ it's always safe, otherwise only safe if there are no `*args` or `**kwargs` used in the signature or call. (#8) - fixed invalid spacing of dots in relative imports (#6, #13) - fixed invalid splitting after comma on unpacked variables in for-loops (#23) - fixed spurious space in parenthesized set expressions (#7) - fixed spurious space after opening parentheses and in default arguments (#14, #17) - fixed spurious space after unary operators when the operand was a complex expression (#15) ## 18.3a0 - first published version, Happy 🍰 Day 2018! - alpha quality - date-versioned (see: )