All patches and comments are welcome. Please squash your changes to logical
commits before using git-format-patch and git-send-email to
patches@git.madduck.net.
If you'd read over the Git project's submission guidelines and adhered to them,
I'd be especially grateful.
7 <!-- Include any especially major or disruptive changes here -->
11 <!-- Changes that affect Black's stable style -->
15 <!-- Changes that affect Black's preview style -->
19 <!-- Changes to blackd -->
23 <!-- Changes to how Black can be configured -->
27 <!-- Major changes to documentation and policies. Small docs changes
28 don't need a changelog entry. -->
30 - Reword the stability policy to say that we may, in rare cases, make changes that
31 affect code that was not previously formatted by _Black_ (#3155)
32 - Recommend using BlackConnect in IntelliJ IDEs (#3150)
36 <!-- For example, Docker, GitHub Actions, pre-commit, editors -->
40 <!-- Changes to Black's terminal output and error messages -->
44 <!-- Changes to how Black is packaged, such as dependency requirements -->
48 <!-- Changes to the parser or to version autodetection -->
52 <!-- Changes that improve Black's performance. -->
58 - Fix unstable formatting involving `#fmt: skip` and `# fmt:skip` comments (notice the
59 lack of spaces) (#2970)
63 - Docstring quotes are no longer moved if it would violate the line length limit (#3044)
64 - Parentheses around return annotations are now managed (#2990)
65 - Remove unnecessary parentheses around awaited objects (#2991)
66 - Remove unnecessary parentheses in `with` statements (#2926)
67 - Remove trailing newlines after code block open (#3035)
71 - Add `scripts/migrate-black.py` script to ease introduction of Black to a Git project
76 - Output Python version and implementation as part of `--version` flag (#2997)
80 - Use `tomli` instead of `tomllib` on Python 3.11 builds where `tomllib` is not
85 - [PEP 654](https://peps.python.org/pep-0654/#except) syntax (for example,
86 `except *ExceptionGroup:`) is now supported (#3016)
87 - [PEP 646](https://peps.python.org/pep-0646) syntax (for example,
88 `Array[Batch, *Shape]` or `def fn(*args: *T) -> None`) is now supported (#3071)
92 - Fix `strtobool` function. It didn't parse true/on/false/off. (#3025)
98 - Code cell separators `#%%` are now standardised to `# %%` (#2919)
99 - Remove unnecessary parentheses from `except` statements (#2939)
100 - Remove unnecessary parentheses from tuple unpacking in `for` loops (#2945)
101 - Avoid magic-trailing-comma in single-element subscripts (#2942)
105 - Do not format `__pypackages__` directories by default (#2836)
106 - Add support for specifying stable version with `--required-version` (#2832).
107 - Avoid crashing when the user has no homedir (#2814)
108 - Avoid crashing when md5 is not available (#2905)
109 - Fix handling of directory junctions on Windows (#2904)
113 - Update pylint config documentation (#2931)
117 - Move test to disable plugin in Vim/Neovim, which speeds up loading (#2896)
121 - In verbose mode, log when _Black_ is using user-level config (#2861)
125 - Fix Black to work with Click 8.1.0 (#2966)
126 - On Python 3.11 and newer, use the standard library's `tomllib` instead of `tomli`
128 - `black-primer`, the deprecated internal devtool, has been removed and copied to a
129 [separate repository](https://github.com/cooperlees/black-primer) (#2924)
133 - Black can now parse starred expressions in the target of `for` and `async for`
134 statements, e.g `for item in *items_1, *items_2: pass` (#2879).
138 At long last, _Black_ is no longer a beta product! This is the first non-beta release
139 and the first release covered by our new
140 [stability policy](https://black.readthedocs.io/en/stable/the_black_code_style/index.html#stability-policy).
144 - **Remove Python 2 support** (#2740)
145 - Introduce the `--preview` flag (#2752)
149 - Deprecate `--experimental-string-processing` and move the functionality under
151 - For stubs, one blank line between class attributes and methods is now kept if there's
152 at least one pre-existing blank line (#2736)
153 - Black now normalizes string prefix order (#2297)
154 - Remove spaces around power operators if both operands are simple (#2726)
155 - Work around bug that causes unstable formatting in some cases in the presence of the
156 magic trailing comma (#2807)
157 - Use parentheses for attribute access on decimal float and int literals (#2799)
158 - Don't add whitespace for attribute access on hexadecimal, binary, octal, and complex
160 - Treat blank lines in stubs the same inside top-level `if` statements (#2820)
161 - Fix unstable formatting with semicolons and arithmetic expressions (#2817)
162 - Fix unstable formatting around magic trailing comma (#2572)
166 - Fix mapping cases that contain as-expressions, like `case {"key": 1 | 2 as password}`
168 - Fix cases that contain multiple top-level as-expressions, like `case 1 as a, 2 as b`
170 - Fix call patterns that contain as-expressions with keyword arguments, like
171 `case Foo(bar=baz as quux)` (#2749)
172 - Tuple unpacking on `return` and `yield` constructs now implies 3.8+ (#2700)
173 - Unparenthesized tuples on annotated assignments (e.g
174 `values: Tuple[int, ...] = 1, 2, 3`) now implies 3.8+ (#2708)
175 - Fix handling of standalone `match()` or `case()` when there is a trailing newline or a
176 comment inside of the parentheses. (#2760)
177 - `from __future__ import annotations` statement now implies Python 3.7+ (#2690)
181 - Speed-up the new backtracking parser about 4X in general (enabled when
182 `--target-version` is set to 3.10 and higher). (#2728)
183 - _Black_ is now compiled with [mypyc](https://github.com/mypyc/mypyc) for an overall 2x
184 speed-up. 64-bit Windows, MacOS, and Linux (not including musl) are supported. (#1009,
189 - Do not accept bare carriage return line endings in pyproject.toml (#2408)
190 - Add configuration option (`python-cell-magics`) to format cells with custom magics in
191 Jupyter Notebooks (#2744)
192 - Allow setting custom cache directory on all platforms with environment variable
193 `BLACK_CACHE_DIR` (#2739).
194 - Enable Python 3.10+ by default, without any extra need to specify
195 `--target-version=py310`. (#2758)
196 - Make passing `SRC` or `--code` mandatory and mutually exclusive (#2804)
200 - Improve error message for invalid regular expression (#2678)
201 - Improve error message when parsing fails during AST safety check by embedding the
202 underlying SyntaxError (#2693)
203 - No longer color diff headers white as it's unreadable in light themed terminals
205 - Text coloring added in the final statistics (#2712)
206 - Verbose mode also now describes how a project root was discovered and which paths will
207 be formatted. (#2526)
211 - All upper version bounds on dependencies have been removed (#2718)
212 - `typing-extensions` is no longer a required dependency in Python 3.10+ (#2772)
213 - Set `click` lower bound to `8.0.0` (#2791)
217 - Update GitHub action to support containerized runs (#2748)
221 - Change protocol in pip installation instructions to `https://` (#2761)
222 - Change HTML theme to Furo primarily for its responsive design and mobile support
224 - Deprecate the `black-primer` tool (#2809)
225 - Document Python support policy (#2819)
231 - Fix determination of f-string expression spans (#2654)
232 - Fix bad formatting of error messages about EOF in multi-line statements (#2343)
233 - Functions and classes in blocks now have more consistent surrounding spacing (#2472)
235 #### Jupyter Notebook support
237 - Cell magics are now only processed if they are known Python cell magics. Earlier, all
238 cell magics were tokenized, leading to possible indentation errors e.g. with
239 `%%writefile`. (#2630)
240 - Fix assignment to environment variables in Jupyter Notebooks (#2642)
242 #### Python 3.10 support
244 - Point users to using `--target-version py310` if we detect 3.10-only syntax (#2668)
245 - Fix `match` statements with open sequence subjects, like `match a, b:` or
246 `match a, *b:` (#2639) (#2659)
247 - Fix `match`/`case` statements that contain `match`/`case` soft keywords multiple
248 times, like `match re.match()` (#2661)
249 - Fix `case` statements with an inline body (#2665)
250 - Fix styling of starred expressions inside `match` subject (#2667)
251 - Fix parser error location on invalid syntax in a `match` statement (#2649)
252 - Fix Python 3.10 support on platforms without ProcessPoolExecutor (#2631)
253 - Improve parsing performance on code that uses `match` under `--target-version py310`
258 - Remove dependency on `regex` (#2644) (#2663)
264 - Bumped regex version minimum to 2021.4.4 to fix Pattern class usage (#2621)
270 - Warn about Python 2 deprecation in more cases by improving Python 2 only syntax
272 - Add experimental PyPy support (#2559)
273 - Add partial support for the match statement. As it's experimental, it's only enabled
274 when `--target-version py310` is explicitly specified (#2586)
275 - Add support for parenthesized with (#2586)
276 - Declare support for Python 3.10 for running Black (#2562)
280 - Fixed vim plugin with Python 3.10 by removing deprecated distutils import (#2610)
281 - The vim plugin now parses `skip_magic_trailing_comma` from pyproject.toml (#2613)
287 - Document stability policy, that will apply for non-beta releases (#2529)
288 - Add new `--workers` parameter (#2514)
289 - Fixed feature detection for positional-only arguments in lambdas (#2532)
290 - Bumped typed-ast version minimum to 1.4.3 for 3.10 compatibility (#2519)
291 - Fixed a Python 3.10 compatibility issue where the loop argument was still being passed
292 even though it has been removed (#2580)
293 - Deprecate Python 2 formatting support (#2523)
297 - Remove dependency on aiohttp-cors (#2500)
298 - Bump required aiohttp version to 3.7.4 (#2509)
302 - Add primer support for --projects (#2555)
303 - Print primer summary after individual failures (#2570)
307 - Allow to pass `target_version` in the vim plugin (#1319)
308 - Install build tools in docker file and use multi-stage build to keep the image size
315 - Fix missing modules in self-contained binaries (#2466)
316 - Fix missing toml extra used during installation (#2475)
322 - Add support for formatting Jupyter Notebook files (#2357)
323 - Move from `appdirs` dependency to `platformdirs` (#2375)
324 - Present a more user-friendly error if .gitignore is invalid (#2414)
325 - The failsafe for accidentally added backslashes in f-string expressions has been
326 hardened to handle more edge cases during quote normalization (#2437)
327 - Avoid changing a function return type annotation's type to a tuple by adding a
328 trailing comma (#2384)
329 - Parsing support has been added for unparenthesized walruses in set literals, set
330 comprehensions, and indices (#2447).
331 - Pin `setuptools-scm` build-time dependency version (#2457)
332 - Exclude typing-extensions version 3.10.0.1 due to it being broken on Python 3.10
337 - Replace sys.exit(-1) with raise ImportError as it plays more nicely with tools that
338 scan installed packages (#2440)
342 - The provided pre-commit hooks no longer specify `language_version` to avoid overriding
343 `default_language_version` (#2430)
349 - Configuration files using TOML features higher than spec v0.5.0 are now supported
351 - Add primer support and test for code piped into black via STDIN (#2315)
352 - Fix internal error when `FORCE_OPTIONAL_PARENTHESES` feature is enabled (#2332)
353 - Accept empty stdin (#2346)
354 - Provide a more useful error when parsing fails during AST safety checks (#2304)
358 - Add new `latest_release` tag automation to follow latest black release on docker
363 - The vim plugin now searches upwards from the directory containing the current buffer
364 instead of the current working directory for pyproject.toml. (#1871)
365 - The vim plugin now reads the correct string normalization option in pyproject.toml
367 - The vim plugin no longer crashes Black when there's boolean values in pyproject.toml
374 - Fix failure caused by `fmt: skip` and indentation (#2281)
375 - Account for += assignment when deciding whether to split string (#2312)
376 - Correct max string length calculation when there are string operators (#2292)
377 - Fixed option usage when using the `--code` flag (#2259)
378 - Do not call `uvloop.install()` when _Black_ is used as a library (#2303)
379 - Added `--required-version` option to require a specific version to be running (#2300)
380 - Fix incorrect custom breakpoint indices when string group contains fake f-strings
382 - Fix regression where `R` prefixes would be lowercased for docstrings (#2285)
383 - Fix handling of named escapes (`\N{...}`) when `--experimental-string-processing` is
388 - The official Black action now supports choosing what version to use, and supports the
389 major 3 OSes. (#1940)
395 - A space is no longer inserted into empty docstrings (#2249)
396 - Fix handling of .gitignore files containing non-ASCII characters on Windows (#2229)
397 - Respect `.gitignore` files in all levels, not only `root/.gitignore` file (apply
398 `.gitignore` rules like `git` does) (#2225)
399 - Restored compatibility with Click 8.0 on Python 3.6 when LANG=C used (#2227)
400 - Add extra uvloop install + import support if in python env (#2258)
401 - Fix --experimental-string-processing crash when matching parens are not found (#2283)
402 - Make sure to split lines that start with a string operator (#2286)
403 - Fix regular expression that black uses to identify f-expressions (#2287)
407 - Add a lower bound for the `aiohttp-cors` dependency. Only 0.4.0 or higher is
412 - Release self-contained x86_64 MacOS binaries as part of the GitHub release pipeline
414 - Always build binaries with the latest available Python (#2260)
418 - Add discussion of magic comments to FAQ page (#2272)
419 - `--experimental-string-processing` will be enabled by default in the future (#2273)
420 - Fix typos discovered by codespell (#2228)
421 - Fix Vim plugin installation instructions. (#2235)
422 - Add new Frequently Asked Questions page (#2247)
423 - Fix encoding + symlink issues preventing proper build on Windows (#2262)
429 - Refactor `src/black/__init__.py` into many files (#2206)
433 - Replaced all remaining references to the
434 [`master`](https://github.com/psf/black/tree/main) branch with the
435 [`main`](https://github.com/psf/black/tree/main) branch. Some additional changes in
436 the source code were also made. (#2210)
437 - Sigificantly reorganized the documentation to make much more sense. Check them out by
438 heading over to [the stable docs on RTD](https://black.readthedocs.io/en/stable/).
445 - Set `--pyi` mode if `--stdin-filename` ends in `.pyi` (#2169)
446 - Stop detecting target version as Python 3.9+ with pre-PEP-614 decorators that are
447 being called but with no arguments (#2182)
451 - Add `--no-diff` to black-primer to suppress formatting changes (#2187)
457 - Fix crash if the user configuration directory is inaccessible. (#2158)
460 [circumstances](https://github.com/psf/black/blob/master/docs/the_black_code_style.md#pragmatism)
461 in which _Black_ may change the AST (#2159)
463 - Allow `.gitignore` rules to be overridden by specifying `exclude` in `pyproject.toml`
464 or on the command line. (#2170)
468 - Install `primer.json` (used by `black-primer` by default) with black. (#2154)
474 - Fix crash on docstrings ending with "\\ ". (#2142)
476 - Fix crash when atypical whitespace is cleaned out of dostrings (#2120)
478 - Reflect the `--skip-magic-trailing-comma` and `--experimental-string-processing` flags
479 in the name of the cache file. Without this fix, changes in these flags would not take
480 effect if the cache had already been populated. (#2131)
482 - Don't remove necessary parentheses from assignment expression containing assert /
483 return statements. (#2143)
487 - Bump pathspec to >= 0.8.1 to solve invalid .gitignore exclusion handling
493 - Fixed a rare but annoying formatting instability created by the combination of
494 optional trailing commas inserted by `Black` and optional parentheses looking at
495 pre-existing "magic" trailing commas. This fixes issue #1629 and all of its many many
498 - `Black` now processes one-line docstrings by stripping leading and trailing spaces,
499 and adding a padding space when needed to break up """". (#1740)
501 - `Black` now cleans up leading non-breaking spaces in comments (#2092)
503 - `Black` now respects `--skip-string-normalization` when normalizing multiline
504 docstring quotes (#1637)
506 - `Black` no longer removes all empty lines between non-function code and decorators
507 when formatting typing stubs. Now `Black` enforces a single empty line. (#1646)
509 - `Black` no longer adds an incorrect space after a parenthesized assignment expression
510 in if/while statements (#1655)
512 - Added `--skip-magic-trailing-comma` / `-C` to avoid using trailing commas as a reason
513 to split lines (#1824)
515 - fixed a crash when PWD=/ on POSIX (#1631)
517 - fixed "I/O operation on closed file" when using --diff (#1664)
519 - Prevent coloured diff output being interleaved with multiple files (#1673)
521 - Added support for PEP 614 relaxed decorator syntax on python 3.9 (#1711)
523 - Added parsing support for unparenthesized tuples and yield expressions in annotated
526 - added `--extend-exclude` argument (PR #2005)
528 - speed up caching by avoiding pathlib (#1950)
530 - `--diff` correctly indicates when a file doesn't end in a newline (#1662)
532 - Added `--stdin-filename` argument to allow stdin to respect `--force-exclude` rules
535 - Lines ending with `fmt: skip` will now be not formatted (#1800)
537 - PR #2053: Black no longer relies on typed-ast for Python 3.8 and higher
539 - PR #2053: Python 2 support is now optional, install with
540 `python3 -m pip install black[python2]` to maintain support.
542 - Exclude `venv` directory by default (#1683)
544 - Fixed "Black produced code that is not equivalent to the source" when formatting
545 Python 2 docstrings (#2037)
549 - Self-contained native _Black_ binaries are now provided for releases via GitHub
556 - explicitly depend on Click 7.1.2 or newer as `Black` no longer works with versions
563 - re-implemented support for explicit trailing commas: now it works consistently within
564 any bracket pair, including nested structures (#1288 and duplicates)
566 - `Black` now reindents docstrings when reindenting code around it (#1053)
568 - `Black` now shows colored diffs (#1266)
570 - `Black` is now packaged using 'py3' tagged wheels (#1388)
572 - `Black` now supports Python 3.8 code, e.g. star expressions in return statements
575 - `Black` no longer normalizes capital R-string prefixes as those have a
576 community-accepted meaning (#1244)
578 - `Black` now uses exit code 2 when specified configuration file doesn't exit (#1361)
580 - `Black` now works on AWS Lambda (#1141)
582 - added `--force-exclude` argument (#1032)
584 - removed deprecated `--py36` option (#1236)
586 - fixed `--diff` output when EOF is encountered (#526)
588 - fixed `# fmt: off` handling around decorators (#560)
590 - fixed unstable formatting with some `# type: ignore` comments (#1113)
592 - fixed invalid removal on organizing brackets followed by indexing (#1575)
594 - introduced `black-primer`, a CI tool that allows us to run regression tests against
595 existing open source users of Black (#1402)
597 - introduced property-based fuzzing to our test suite based on Hypothesis and
598 Hypothersmith (#1566)
600 - implemented experimental and disabled by default long string rewrapping (#1132),
601 hidden under a `--experimental-string-processing` flag while it's being worked on;
602 this is an undocumented and unsupported feature, you lose Internet points for
603 depending on it (#1609)
607 - prefer virtualenv packages over global packages (#1383)
611 - added support for PEP 572 assignment expressions (#711)
613 - added support for PEP 570 positional-only arguments (#943)
615 - added support for async generators (#593)
617 - added support for pre-splitting collections by putting an explicit trailing comma
620 - added `black -c` as a way to format code passed from the command line (#761)
622 - --safe now works with Python 2 code (#840)
624 - fixed grammar selection for Python 2-specific code (#765)
626 - fixed feature detection for trailing commas in function definitions and call sites
629 - `# fmt: off`/`# fmt: on` comment pairs placed multiple times within the same block of
630 code now behave correctly (#1005)
632 - _Black_ no longer crashes on Windows machines with more than 61 cores (#838)
634 - _Black_ no longer crashes on standalone comments prepended with a backslash (#767)
636 - _Black_ no longer crashes on `from` ... `import` blocks with comments (#829)
638 - _Black_ no longer crashes on Python 3.7 on some platform configurations (#494)
640 - _Black_ no longer fails on comments in from-imports (#671)
642 - _Black_ no longer fails when the file starts with a backslash (#922)
644 - _Black_ no longer merges regular comments with type comments (#1027)
646 - _Black_ no longer splits long lines that contain type comments (#997)
648 - removed unnecessary parentheses around `yield` expressions (#834)
650 - added parentheses around long tuples in unpacking assignments (#832)
652 - added parentheses around complex powers when they are prefixed by a unary operator
655 - fixed bug that led _Black_ format some code with a line length target of 1 (#762)
657 - _Black_ no longer introduces quotes in f-string subexpressions on string boundaries
660 - if _Black_ puts parenthesis around a single expression, it moves comments to the
661 wrapped expression instead of after the brackets (#872)
663 - `blackd` now returns the version of _Black_ in the response headers (#1013)
665 - `blackd` can now output the diff of formats on source code when the `X-Diff` header is
670 - new option `--target-version` to control which Python versions _Black_-formatted code
673 - deprecated `--py36` (use `--target-version=py36` instead) (#724)
675 - _Black_ no longer normalizes numeric literals to include `_` separators (#696)
677 - long `del` statements are now split into multiple lines (#698)
679 - type comments are no longer mangled in function signatures
681 - improved performance of formatting deeply nested data structures (#509)
683 - _Black_ now properly formats multiple files in parallel on Windows (#632)
685 - _Black_ now creates cache files atomically which allows it to be used in parallel
686 pipelines (like `xargs -P8`) (#673)
688 - _Black_ now correctly indents comments in files that were previously formatted with
691 - `blackd` now supports CORS (#622)
695 - numeric literals are now formatted by _Black_ (#452, #461, #464, #469):
697 - numeric literals are normalized to include `_` separators on Python 3.6+ code
699 - added `--skip-numeric-underscore-normalization` to disable the above behavior and
700 leave numeric underscores as they were in the input
702 - code with `_` in numeric literals is recognized as Python 3.6+
704 - most letters in numeric literals are lowercased (e.g., in `1e10`, `0x01`)
706 - hexadecimal digits are always uppercased (e.g. `0xBADC0DE`)
708 - added `blackd`, see
709 [its documentation](https://github.com/psf/black/blob/18.9b0/README.md#blackd) for
712 - adjacent string literals are now correctly split into multiple lines (#463)
714 - trailing comma is now added to single imports that don't fit on a line (#250)
716 - cache is now populated when `--check` is successful for a file which speeds up
717 consecutive checks of properly formatted unmodified files (#448)
719 - whitespace at the beginning of the file is now removed (#399)
721 - fixed mangling [pweave](http://mpastell.com/pweave/) and
722 [Spyder IDE](https://www.spyder-ide.org/) special comments (#532)
724 - fixed unstable formatting when unpacking big tuples (#267)
726 - fixed parsing of `__future__` imports with renames (#389)
728 - fixed scope of `# fmt: off` when directly preceding `yield` and other nodes (#385)
730 - fixed formatting of lambda expressions with default arguments (#468)
732 - fixed `async for` statements: _Black_ no longer breaks them into separate lines (#372)
734 - note: the Vim plugin stopped registering `,=` as a default chord as it turned out to
739 - hotfix: don't freeze when multiple comments directly precede `# fmt: off` (#371)
743 - typing stub files (`.pyi`) now have blank lines added after constants (#340)
745 - `# fmt: off` and `# fmt: on` are now much more dependable:
747 - they now work also within bracket pairs (#329)
749 - they now correctly work across function/class boundaries (#335)
751 - they now work when an indentation block starts with empty lines or misaligned
754 - made Click not fail on invalid environments; note that Click is right but the
755 likelihood we'll need to access non-ASCII file paths when dealing with Python source
758 - fixed improper formatting of f-strings with quotes inside interpolated expressions
761 - fixed unnecessary slowdown when long list literals where found in a file
763 - fixed unnecessary slowdown on AST nodes with very many siblings
765 - fixed cannibalizing backslashes during string normalization
767 - fixed a crash due to symbolic links pointing outside of the project directory (#338)
771 - added `--config` (#65)
773 - added `-h` equivalent to `--help` (#316)
775 - fixed improper unmodified file caching when `-S` was used
777 - fixed extra space in string unpacking (#305)
779 - fixed formatting of empty triple quoted strings (#313)
781 - fixed unnecessary slowdown in comment placement calculation on lines without comments
785 - hotfix: don't output human-facing information on stdout (#299)
787 - hotfix: don't output cake emoji on non-zero return code (#300)
791 - added `--include` and `--exclude` (#270)
793 - added `--skip-string-normalization` (#118)
795 - added `--verbose` (#283)
797 - the header output in `--diff` now actually conforms to the unified diff spec
799 - fixed long trivial assignments being wrapped in unnecessary parentheses (#273)
801 - fixed unnecessary parentheses when a line contained multiline strings (#232)
803 - fixed stdin handling not working correctly if an old version of Click was used (#276)
805 - _Black_ now preserves line endings when formatting a file in place (#258)
809 - added `--pyi` (#249)
811 - added `--py36` (#249)
813 - Python grammar pickle caches are stored with the formatting caches, making _Black_
814 work in environments where site-packages is not user-writable (#192)
816 - _Black_ now enforces a PEP 257 empty line after a class-level docstring (and/or
817 fields) and the first method
819 - fixed invalid code produced when standalone comments were present in a trailer that
820 was omitted from line splitting on a large expression (#237)
822 - fixed optional parentheses being removed within `# fmt: off` sections (#224)
824 - fixed invalid code produced when stars in very long imports were incorrectly wrapped
825 in optional parentheses (#234)
827 - fixed unstable formatting when inline comments were moved around in a trailer that was
828 omitted from line splitting on a large expression (#238)
830 - fixed extra empty line between a class declaration and the first method if no class
831 docstring or fields are present (#219)
833 - fixed extra empty line between a function signature and an inner function or inner
838 - call chains are now formatted according to the
839 [fluent interfaces](https://en.wikipedia.org/wiki/Fluent_interface) style (#67)
841 - data structure literals (tuples, lists, dictionaries, and sets) are now also always
842 exploded like imports when they don't fit in a single line (#152)
844 - slices are now formatted according to PEP 8 (#178)
846 - parentheses are now also managed automatically on the right-hand side of assignments
847 and return statements (#140)
849 - math operators now use their respective priorities for delimiting multiline
852 - optional parentheses are now omitted on expressions that start or end with a bracket
853 and only contain a single operator (#177)
855 - empty parentheses in a class definition are now removed (#145, #180)
857 - string prefixes are now standardized to lowercase and `u` is removed on Python 3.6+
858 only code and Python 2.7+ code with the `unicode_literals` future import (#188, #198,
861 - typing stub files (`.pyi`) are now formatted in a style that is consistent with PEP
864 - progress when reformatting many files is now reported incrementally
866 - fixed trailers (content with brackets) being unnecessarily exploded into their own
867 lines after a dedented closing bracket (#119)
869 - fixed an invalid trailing comma sometimes left in imports (#185)
871 - fixed non-deterministic formatting when multiple pairs of removable parentheses were
874 - fixed multiline strings being unnecessarily wrapped in optional parentheses in long
877 - fixed not splitting long from-imports with only a single name
879 - fixed Python 3.6+ file discovery by also looking at function calls with unpacking.
880 This fixed non-deterministic formatting if trailing commas where used both in function
881 signatures with stars and function calls with stars but the former would be
882 reformatted to a single line.
884 - fixed crash on dealing with optional parentheses (#193)
886 - fixed "is", "is not", "in", and "not in" not considered operators for splitting
889 - fixed crash when dead symlinks where encountered
893 - don't populate the cache on `--check` (#175)
897 - added a "cache"; files already reformatted that haven't changed on disk won't be
898 reformatted again (#109)
900 - `--check` and `--diff` are no longer mutually exclusive (#149)
902 - generalized star expression handling, including double stars; this fixes
903 multiplication making expressions "unsafe" for trailing commas (#132)
905 - _Black_ no longer enforces putting empty lines behind control flow statements (#90)
907 - _Black_ now splits imports like "Mode 3 + trailing comma" of isort (#127)
909 - fixed comment indentation when a standalone comment closes a block (#16, #32)
911 - fixed standalone comments receiving extra empty lines if immediately preceding a
912 class, def, or decorator (#56, #154)
914 - fixed `--diff` not showing entire path (#130)
916 - fixed parsing of complex expressions after star and double stars in function calls
919 - fixed invalid splitting on comma in lambda arguments (#133)
921 - fixed missing splits of ternary expressions (#141)
925 - fixed parsing of unaligned standalone comments (#99, #112)
927 - fixed placement of dictionary unpacking inside dictionary literals (#111)
929 - Vim plugin now works on Windows, too
931 - fixed unstable formatting when encountering unnecessarily escaped quotes in a string
936 - added `--quiet` (#78)
938 - added automatic parentheses management (#4)
940 - added [pre-commit](https://pre-commit.com) integration (#103, #104)
942 - fixed reporting on `--check` with multiple files (#101, #102)
944 - fixed removing backslash escapes from raw strings (#100, #105)
948 - added `--diff` (#87)
950 - add line breaks before all delimiters, except in cases like commas, to better comply
953 - standardize string literals to use double quotes (almost) everywhere (#75)
955 - fixed handling of standalone comments within nested bracketed expressions; _Black_
956 will no longer produce super long lines or put all standalone comments at the end of
959 - fixed 18.3a4 regression: don't crash and burn on empty lines with trailing whitespace
962 - fixed 18.3a4 regression: `# yapf: disable` usage as trailing comment would cause
963 _Black_ to not emit the rest of the file (#95)
965 - when CTRL+C is pressed while formatting many files, _Black_ no longer freaks out with
966 a flurry of asyncio-related exceptions
968 - only allow up to two empty lines on module level and only single empty lines within
973 - `# fmt: off` and `# fmt: on` are implemented (#5)
975 - automatic detection of deprecated Python 2 forms of print statements and exec
976 statements in the formatted file (#49)
978 - use proper spaces for complex expressions in default values of typed function
981 - only return exit code 1 when --check is used (#50)
983 - don't remove single trailing commas from square bracket indexing (#59)
985 - don't omit whitespace if the previous factor leaf wasn't a math operator (#55)
987 - omit extra space in kwarg unpacking if it's the first argument (#46)
989 - omit extra space in
990 [Sphinx auto-attribute comments](http://www.sphinx-doc.org/en/stable/ext/autodoc.html#directive-autoattribute)
995 - don't remove single empty lines outside of bracketed expressions (#19)
997 - added ability to pipe formatting from stdin to stdin (#25)
999 - restored ability to format code with legacy usage of `async` as a name (#20, #42)
1001 - even better handling of numpy-style array indexing (#33, again)
1005 - changed positioning of binary operators to occur at beginning of lines instead of at
1007 [a recent change to PEP 8](https://github.com/python/peps/commit/c59c4376ad233a62ca4b3a6060c81368bd21e85b)
1010 - ignore empty bracket pairs while splitting. This avoids very weirdly looking
1011 formattings (#34, #35)
1013 - remove a trailing comma if there is a single argument to a call
1015 - if top level functions were separated by a comment, don't put four empty lines after
1018 - fixed unstable formatting of newlines with imports
1020 - fixed unintentional folding of post scriptum standalone comments into last statement
1021 if it was a simple statement (#18, #28)
1023 - fixed missing space in numpy-style array indexing (#33)
1025 - fixed spurious space after star-based unary expressions (#31)
1031 - only put trailing commas in function signatures and calls if it's safe to do so. If
1032 the file is Python 3.6+ it's always safe, otherwise only safe if there are no `*args`
1033 or `**kwargs` used in the signature or call. (#8)
1035 - fixed invalid spacing of dots in relative imports (#6, #13)
1037 - fixed invalid splitting after comma on unpacked variables in for-loops (#23)
1039 - fixed spurious space in parenthesized set expressions (#7)
1041 - fixed spurious space after opening parentheses and in default arguments (#14, #17)
1043 - fixed spurious space after unary operators when the operand was a complex expression
1048 - first published version, Happy 🍰 Day 2018!
1052 - date-versioned (see: <https://calver.org/>)