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 -->
9 - Runtime support for Python 3.6 has been removed. Formatting 3.6 code will still be
10 supported until further notice.
14 <!-- Changes that affect Black's stable style -->
16 - Fix a crash when `# fmt: on` is used on a different block level than `# fmt: off`
21 <!-- Changes that affect Black's preview style -->
23 - Fix a crash when formatting some dicts with parenthesis-wrapped long string keys
28 <!-- Changes to how Black can be configured -->
30 - `.ipynb_checkpoints` directories are now excluded by default (#3293)
34 <!-- Changes to how Black is packaged, such as dependency requirements -->
36 - Executables made with PyInstaller will no longer crash when formatting several files
37 at once on macOS. Native x86-64 executables for macOS are available once again.
39 - Hatchling is now used as the build backend. This will not have any effect for users
40 who install Black with its wheels from PyPI. (#3233)
41 - Faster compiled wheels are now available for CPython 3.11 (#3276)
45 <!-- Changes to the parser or to version autodetection -->
49 <!-- Changes that improve Black's performance. -->
53 <!-- Changes to Black's terminal output and error messages -->
57 <!-- Changes to blackd -->
61 <!-- For example, Docker, GitHub Actions, pre-commit, editors -->
63 - Update GitHub Action to support formatting of Jupyter Notebook files via a `jupyter`
65 - Update GitHub Action to support use of version specifiers (e.g. `<23`) for Black
70 <!-- Major changes to documentation and policies. Small docs changes
71 don't need a changelog entry. -->
77 - Python 3.11 is now supported, except for _blackd_ as aiohttp does not support 3.11 as
79 - This is the last release that supports running _Black_ on Python 3.6 (formatting 3.6
80 code will continue to be supported until further notice)
81 - Reword the stability policy to say that we may, in rare cases, make changes that
82 affect code that was not previously formatted by _Black_ (#3155)
86 - Fix an infinite loop when using `# fmt: on/off` in the middle of an expression or code
88 - Fix incorrect handling of `# fmt: skip` on colon (`:`) lines (#3148)
89 - Comments are no longer deleted when a line had spaces removed around power operators
94 - Single-character closing docstring quotes are no longer moved to their own line as
95 this is invalid. This was a bug introduced in version 22.6.0. (#3166)
96 - `--skip-string-normalization` / `-S` now prevents docstring prefixes from being
97 normalized as expected (#3168)
98 - When using `--skip-magic-trailing-comma` or `-C`, trailing commas are stripped from
99 subscript expressions with more than 1 element (#3209)
100 - Implicitly concatenated strings inside a list, set, or tuple are now wrapped inside
102 - Fix a string merging/split issue when a comment is present in the middle of implicitly
103 concatenated strings on its own line (#3227)
107 - `blackd` now supports enabling the preview style via the `X-Preview` header (#3217)
111 - Black now uses the presence of debug f-strings to detect target version (#3215)
112 - Fix misdetection of project root and verbose logging of sources in cases involving
113 `--stdin-filename` (#3216)
114 - Immediate `.gitignore` files in source directories given on the command line are now
115 also respected, previously only `.gitignore` files in the project root and
116 automatically discovered directories were respected (#3237)
120 - Recommend using BlackConnect in IntelliJ IDEs (#3150)
124 - Vim plugin: prefix messages with `Black: ` so it's clear they come from Black (#3194)
125 - Docker: changed to a /opt/venv installation + added to PATH to be available to
126 non-root users (#3202)
127 - Vim plugin: add flag (`g:black_preview`) to enable/disable the preview style (#3246)
131 - Change from deprecated `asyncio.get_event_loop()` to create our event loop which
132 removes DeprecationWarning (#3164)
133 - Remove logging from internal `blib2to3` library since it regularly emits error logs
134 about failed caching that can and should be ignored (#3193)
138 - Type comments are now included in the AST equivalence check consistently so accidental
139 deletion raises an error. Though type comments can't be tracked when running on PyPy
140 3.7 due to standard library limitations. (#2874)
144 - Reduce Black's startup time when formatting a single file by 15-30% (#3211)
150 - Fix unstable formatting involving `#fmt: skip` and `# fmt:skip` comments (notice the
151 lack of spaces) (#2970)
155 - Docstring quotes are no longer moved if it would violate the line length limit (#3044)
156 - Parentheses around return annotations are now managed (#2990)
157 - Remove unnecessary parentheses around awaited objects (#2991)
158 - Remove unnecessary parentheses in `with` statements (#2926)
159 - Remove trailing newlines after code block open (#3035)
163 - Add `scripts/migrate-black.py` script to ease introduction of Black to a Git project
168 - Output Python version and implementation as part of `--version` flag (#2997)
172 - Use `tomli` instead of `tomllib` on Python 3.11 builds where `tomllib` is not
177 - [PEP 654](https://peps.python.org/pep-0654/#except) syntax (for example,
178 `except *ExceptionGroup:`) is now supported (#3016)
179 - [PEP 646](https://peps.python.org/pep-0646) syntax (for example,
180 `Array[Batch, *Shape]` or `def fn(*args: *T) -> None`) is now supported (#3071)
184 - Fix `strtobool` function. It didn't parse true/on/false/off. (#3025)
190 - Code cell separators `#%%` are now standardised to `# %%` (#2919)
191 - Remove unnecessary parentheses from `except` statements (#2939)
192 - Remove unnecessary parentheses from tuple unpacking in `for` loops (#2945)
193 - Avoid magic-trailing-comma in single-element subscripts (#2942)
197 - Do not format `__pypackages__` directories by default (#2836)
198 - Add support for specifying stable version with `--required-version` (#2832).
199 - Avoid crashing when the user has no homedir (#2814)
200 - Avoid crashing when md5 is not available (#2905)
201 - Fix handling of directory junctions on Windows (#2904)
205 - Update pylint config documentation (#2931)
209 - Move test to disable plugin in Vim/Neovim, which speeds up loading (#2896)
213 - In verbose mode, log when _Black_ is using user-level config (#2861)
217 - Fix Black to work with Click 8.1.0 (#2966)
218 - On Python 3.11 and newer, use the standard library's `tomllib` instead of `tomli`
220 - `black-primer`, the deprecated internal devtool, has been removed and copied to a
221 [separate repository](https://github.com/cooperlees/black-primer) (#2924)
225 - Black can now parse starred expressions in the target of `for` and `async for`
226 statements, e.g `for item in *items_1, *items_2: pass` (#2879).
230 At long last, _Black_ is no longer a beta product! This is the first non-beta release
231 and the first release covered by our new
232 [stability policy](https://black.readthedocs.io/en/stable/the_black_code_style/index.html#stability-policy).
236 - **Remove Python 2 support** (#2740)
237 - Introduce the `--preview` flag (#2752)
241 - Deprecate `--experimental-string-processing` and move the functionality under
243 - For stubs, one blank line between class attributes and methods is now kept if there's
244 at least one pre-existing blank line (#2736)
245 - Black now normalizes string prefix order (#2297)
246 - Remove spaces around power operators if both operands are simple (#2726)
247 - Work around bug that causes unstable formatting in some cases in the presence of the
248 magic trailing comma (#2807)
249 - Use parentheses for attribute access on decimal float and int literals (#2799)
250 - Don't add whitespace for attribute access on hexadecimal, binary, octal, and complex
252 - Treat blank lines in stubs the same inside top-level `if` statements (#2820)
253 - Fix unstable formatting with semicolons and arithmetic expressions (#2817)
254 - Fix unstable formatting around magic trailing comma (#2572)
258 - Fix mapping cases that contain as-expressions, like `case {"key": 1 | 2 as password}`
260 - Fix cases that contain multiple top-level as-expressions, like `case 1 as a, 2 as b`
262 - Fix call patterns that contain as-expressions with keyword arguments, like
263 `case Foo(bar=baz as quux)` (#2749)
264 - Tuple unpacking on `return` and `yield` constructs now implies 3.8+ (#2700)
265 - Unparenthesized tuples on annotated assignments (e.g
266 `values: Tuple[int, ...] = 1, 2, 3`) now implies 3.8+ (#2708)
267 - Fix handling of standalone `match()` or `case()` when there is a trailing newline or a
268 comment inside of the parentheses. (#2760)
269 - `from __future__ import annotations` statement now implies Python 3.7+ (#2690)
273 - Speed-up the new backtracking parser about 4X in general (enabled when
274 `--target-version` is set to 3.10 and higher). (#2728)
275 - _Black_ is now compiled with [mypyc](https://github.com/mypyc/mypyc) for an overall 2x
276 speed-up. 64-bit Windows, MacOS, and Linux (not including musl) are supported. (#1009,
281 - Do not accept bare carriage return line endings in pyproject.toml (#2408)
282 - Add configuration option (`python-cell-magics`) to format cells with custom magics in
283 Jupyter Notebooks (#2744)
284 - Allow setting custom cache directory on all platforms with environment variable
285 `BLACK_CACHE_DIR` (#2739).
286 - Enable Python 3.10+ by default, without any extra need to specify
287 `--target-version=py310`. (#2758)
288 - Make passing `SRC` or `--code` mandatory and mutually exclusive (#2804)
292 - Improve error message for invalid regular expression (#2678)
293 - Improve error message when parsing fails during AST safety check by embedding the
294 underlying SyntaxError (#2693)
295 - No longer color diff headers white as it's unreadable in light themed terminals
297 - Text coloring added in the final statistics (#2712)
298 - Verbose mode also now describes how a project root was discovered and which paths will
299 be formatted. (#2526)
303 - All upper version bounds on dependencies have been removed (#2718)
304 - `typing-extensions` is no longer a required dependency in Python 3.10+ (#2772)
305 - Set `click` lower bound to `8.0.0` (#2791)
309 - Update GitHub action to support containerized runs (#2748)
313 - Change protocol in pip installation instructions to `https://` (#2761)
314 - Change HTML theme to Furo primarily for its responsive design and mobile support
316 - Deprecate the `black-primer` tool (#2809)
317 - Document Python support policy (#2819)
323 - Fix determination of f-string expression spans (#2654)
324 - Fix bad formatting of error messages about EOF in multi-line statements (#2343)
325 - Functions and classes in blocks now have more consistent surrounding spacing (#2472)
327 #### Jupyter Notebook support
329 - Cell magics are now only processed if they are known Python cell magics. Earlier, all
330 cell magics were tokenized, leading to possible indentation errors e.g. with
331 `%%writefile`. (#2630)
332 - Fix assignment to environment variables in Jupyter Notebooks (#2642)
334 #### Python 3.10 support
336 - Point users to using `--target-version py310` if we detect 3.10-only syntax (#2668)
337 - Fix `match` statements with open sequence subjects, like `match a, b:` or
338 `match a, *b:` (#2639) (#2659)
339 - Fix `match`/`case` statements that contain `match`/`case` soft keywords multiple
340 times, like `match re.match()` (#2661)
341 - Fix `case` statements with an inline body (#2665)
342 - Fix styling of starred expressions inside `match` subject (#2667)
343 - Fix parser error location on invalid syntax in a `match` statement (#2649)
344 - Fix Python 3.10 support on platforms without ProcessPoolExecutor (#2631)
345 - Improve parsing performance on code that uses `match` under `--target-version py310`
350 - Remove dependency on `regex` (#2644) (#2663)
356 - Bumped regex version minimum to 2021.4.4 to fix Pattern class usage (#2621)
362 - Warn about Python 2 deprecation in more cases by improving Python 2 only syntax
364 - Add experimental PyPy support (#2559)
365 - Add partial support for the match statement. As it's experimental, it's only enabled
366 when `--target-version py310` is explicitly specified (#2586)
367 - Add support for parenthesized with (#2586)
368 - Declare support for Python 3.10 for running Black (#2562)
372 - Fixed vim plugin with Python 3.10 by removing deprecated distutils import (#2610)
373 - The vim plugin now parses `skip_magic_trailing_comma` from pyproject.toml (#2613)
379 - Document stability policy, that will apply for non-beta releases (#2529)
380 - Add new `--workers` parameter (#2514)
381 - Fixed feature detection for positional-only arguments in lambdas (#2532)
382 - Bumped typed-ast version minimum to 1.4.3 for 3.10 compatibility (#2519)
383 - Fixed a Python 3.10 compatibility issue where the loop argument was still being passed
384 even though it has been removed (#2580)
385 - Deprecate Python 2 formatting support (#2523)
389 - Remove dependency on aiohttp-cors (#2500)
390 - Bump required aiohttp version to 3.7.4 (#2509)
394 - Add primer support for --projects (#2555)
395 - Print primer summary after individual failures (#2570)
399 - Allow to pass `target_version` in the vim plugin (#1319)
400 - Install build tools in docker file and use multi-stage build to keep the image size
407 - Fix missing modules in self-contained binaries (#2466)
408 - Fix missing toml extra used during installation (#2475)
414 - Add support for formatting Jupyter Notebook files (#2357)
415 - Move from `appdirs` dependency to `platformdirs` (#2375)
416 - Present a more user-friendly error if .gitignore is invalid (#2414)
417 - The failsafe for accidentally added backslashes in f-string expressions has been
418 hardened to handle more edge cases during quote normalization (#2437)
419 - Avoid changing a function return type annotation's type to a tuple by adding a
420 trailing comma (#2384)
421 - Parsing support has been added for unparenthesized walruses in set literals, set
422 comprehensions, and indices (#2447).
423 - Pin `setuptools-scm` build-time dependency version (#2457)
424 - Exclude typing-extensions version 3.10.0.1 due to it being broken on Python 3.10
429 - Replace sys.exit(-1) with raise ImportError as it plays more nicely with tools that
430 scan installed packages (#2440)
434 - The provided pre-commit hooks no longer specify `language_version` to avoid overriding
435 `default_language_version` (#2430)
441 - Configuration files using TOML features higher than spec v0.5.0 are now supported
443 - Add primer support and test for code piped into black via STDIN (#2315)
444 - Fix internal error when `FORCE_OPTIONAL_PARENTHESES` feature is enabled (#2332)
445 - Accept empty stdin (#2346)
446 - Provide a more useful error when parsing fails during AST safety checks (#2304)
450 - Add new `latest_release` tag automation to follow latest black release on docker
455 - The vim plugin now searches upwards from the directory containing the current buffer
456 instead of the current working directory for pyproject.toml. (#1871)
457 - The vim plugin now reads the correct string normalization option in pyproject.toml
459 - The vim plugin no longer crashes Black when there's boolean values in pyproject.toml
466 - Fix failure caused by `fmt: skip` and indentation (#2281)
467 - Account for += assignment when deciding whether to split string (#2312)
468 - Correct max string length calculation when there are string operators (#2292)
469 - Fixed option usage when using the `--code` flag (#2259)
470 - Do not call `uvloop.install()` when _Black_ is used as a library (#2303)
471 - Added `--required-version` option to require a specific version to be running (#2300)
472 - Fix incorrect custom breakpoint indices when string group contains fake f-strings
474 - Fix regression where `R` prefixes would be lowercased for docstrings (#2285)
475 - Fix handling of named escapes (`\N{...}`) when `--experimental-string-processing` is
480 - The official Black action now supports choosing what version to use, and supports the
481 major 3 OSes. (#1940)
487 - A space is no longer inserted into empty docstrings (#2249)
488 - Fix handling of .gitignore files containing non-ASCII characters on Windows (#2229)
489 - Respect `.gitignore` files in all levels, not only `root/.gitignore` file (apply
490 `.gitignore` rules like `git` does) (#2225)
491 - Restored compatibility with Click 8.0 on Python 3.6 when LANG=C used (#2227)
492 - Add extra uvloop install + import support if in python env (#2258)
493 - Fix --experimental-string-processing crash when matching parens are not found (#2283)
494 - Make sure to split lines that start with a string operator (#2286)
495 - Fix regular expression that black uses to identify f-expressions (#2287)
499 - Add a lower bound for the `aiohttp-cors` dependency. Only 0.4.0 or higher is
504 - Release self-contained x86_64 MacOS binaries as part of the GitHub release pipeline
506 - Always build binaries with the latest available Python (#2260)
510 - Add discussion of magic comments to FAQ page (#2272)
511 - `--experimental-string-processing` will be enabled by default in the future (#2273)
512 - Fix typos discovered by codespell (#2228)
513 - Fix Vim plugin installation instructions. (#2235)
514 - Add new Frequently Asked Questions page (#2247)
515 - Fix encoding + symlink issues preventing proper build on Windows (#2262)
521 - Refactor `src/black/__init__.py` into many files (#2206)
525 - Replaced all remaining references to the
526 [`master`](https://github.com/psf/black/tree/main) branch with the
527 [`main`](https://github.com/psf/black/tree/main) branch. Some additional changes in
528 the source code were also made. (#2210)
529 - Sigificantly reorganized the documentation to make much more sense. Check them out by
530 heading over to [the stable docs on RTD](https://black.readthedocs.io/en/stable/).
537 - Set `--pyi` mode if `--stdin-filename` ends in `.pyi` (#2169)
538 - Stop detecting target version as Python 3.9+ with pre-PEP-614 decorators that are
539 being called but with no arguments (#2182)
543 - Add `--no-diff` to black-primer to suppress formatting changes (#2187)
549 - Fix crash if the user configuration directory is inaccessible. (#2158)
552 [circumstances](https://github.com/psf/black/blob/master/docs/the_black_code_style.md#pragmatism)
553 in which _Black_ may change the AST (#2159)
555 - Allow `.gitignore` rules to be overridden by specifying `exclude` in `pyproject.toml`
556 or on the command line. (#2170)
560 - Install `primer.json` (used by `black-primer` by default) with black. (#2154)
566 - Fix crash on docstrings ending with "\\ ". (#2142)
568 - Fix crash when atypical whitespace is cleaned out of dostrings (#2120)
570 - Reflect the `--skip-magic-trailing-comma` and `--experimental-string-processing` flags
571 in the name of the cache file. Without this fix, changes in these flags would not take
572 effect if the cache had already been populated. (#2131)
574 - Don't remove necessary parentheses from assignment expression containing assert /
575 return statements. (#2143)
579 - Bump pathspec to >= 0.8.1 to solve invalid .gitignore exclusion handling
585 - Fixed a rare but annoying formatting instability created by the combination of
586 optional trailing commas inserted by `Black` and optional parentheses looking at
587 pre-existing "magic" trailing commas. This fixes issue #1629 and all of its many many
590 - `Black` now processes one-line docstrings by stripping leading and trailing spaces,
591 and adding a padding space when needed to break up """". (#1740)
593 - `Black` now cleans up leading non-breaking spaces in comments (#2092)
595 - `Black` now respects `--skip-string-normalization` when normalizing multiline
596 docstring quotes (#1637)
598 - `Black` no longer removes all empty lines between non-function code and decorators
599 when formatting typing stubs. Now `Black` enforces a single empty line. (#1646)
601 - `Black` no longer adds an incorrect space after a parenthesized assignment expression
602 in if/while statements (#1655)
604 - Added `--skip-magic-trailing-comma` / `-C` to avoid using trailing commas as a reason
605 to split lines (#1824)
607 - fixed a crash when PWD=/ on POSIX (#1631)
609 - fixed "I/O operation on closed file" when using --diff (#1664)
611 - Prevent coloured diff output being interleaved with multiple files (#1673)
613 - Added support for PEP 614 relaxed decorator syntax on python 3.9 (#1711)
615 - Added parsing support for unparenthesized tuples and yield expressions in annotated
618 - added `--extend-exclude` argument (PR #2005)
620 - speed up caching by avoiding pathlib (#1950)
622 - `--diff` correctly indicates when a file doesn't end in a newline (#1662)
624 - Added `--stdin-filename` argument to allow stdin to respect `--force-exclude` rules
627 - Lines ending with `fmt: skip` will now be not formatted (#1800)
629 - PR #2053: Black no longer relies on typed-ast for Python 3.8 and higher
631 - PR #2053: Python 2 support is now optional, install with
632 `python3 -m pip install black[python2]` to maintain support.
634 - Exclude `venv` directory by default (#1683)
636 - Fixed "Black produced code that is not equivalent to the source" when formatting
637 Python 2 docstrings (#2037)
641 - Self-contained native _Black_ binaries are now provided for releases via GitHub
648 - explicitly depend on Click 7.1.2 or newer as `Black` no longer works with versions
655 - re-implemented support for explicit trailing commas: now it works consistently within
656 any bracket pair, including nested structures (#1288 and duplicates)
658 - `Black` now reindents docstrings when reindenting code around it (#1053)
660 - `Black` now shows colored diffs (#1266)
662 - `Black` is now packaged using 'py3' tagged wheels (#1388)
664 - `Black` now supports Python 3.8 code, e.g. star expressions in return statements
667 - `Black` no longer normalizes capital R-string prefixes as those have a
668 community-accepted meaning (#1244)
670 - `Black` now uses exit code 2 when specified configuration file doesn't exit (#1361)
672 - `Black` now works on AWS Lambda (#1141)
674 - added `--force-exclude` argument (#1032)
676 - removed deprecated `--py36` option (#1236)
678 - fixed `--diff` output when EOF is encountered (#526)
680 - fixed `# fmt: off` handling around decorators (#560)
682 - fixed unstable formatting with some `# type: ignore` comments (#1113)
684 - fixed invalid removal on organizing brackets followed by indexing (#1575)
686 - introduced `black-primer`, a CI tool that allows us to run regression tests against
687 existing open source users of Black (#1402)
689 - introduced property-based fuzzing to our test suite based on Hypothesis and
690 Hypothersmith (#1566)
692 - implemented experimental and disabled by default long string rewrapping (#1132),
693 hidden under a `--experimental-string-processing` flag while it's being worked on;
694 this is an undocumented and unsupported feature, you lose Internet points for
695 depending on it (#1609)
699 - prefer virtualenv packages over global packages (#1383)
703 - added support for PEP 572 assignment expressions (#711)
705 - added support for PEP 570 positional-only arguments (#943)
707 - added support for async generators (#593)
709 - added support for pre-splitting collections by putting an explicit trailing comma
712 - added `black -c` as a way to format code passed from the command line (#761)
714 - --safe now works with Python 2 code (#840)
716 - fixed grammar selection for Python 2-specific code (#765)
718 - fixed feature detection for trailing commas in function definitions and call sites
721 - `# fmt: off`/`# fmt: on` comment pairs placed multiple times within the same block of
722 code now behave correctly (#1005)
724 - _Black_ no longer crashes on Windows machines with more than 61 cores (#838)
726 - _Black_ no longer crashes on standalone comments prepended with a backslash (#767)
728 - _Black_ no longer crashes on `from` ... `import` blocks with comments (#829)
730 - _Black_ no longer crashes on Python 3.7 on some platform configurations (#494)
732 - _Black_ no longer fails on comments in from-imports (#671)
734 - _Black_ no longer fails when the file starts with a backslash (#922)
736 - _Black_ no longer merges regular comments with type comments (#1027)
738 - _Black_ no longer splits long lines that contain type comments (#997)
740 - removed unnecessary parentheses around `yield` expressions (#834)
742 - added parentheses around long tuples in unpacking assignments (#832)
744 - added parentheses around complex powers when they are prefixed by a unary operator
747 - fixed bug that led _Black_ format some code with a line length target of 1 (#762)
749 - _Black_ no longer introduces quotes in f-string subexpressions on string boundaries
752 - if _Black_ puts parenthesis around a single expression, it moves comments to the
753 wrapped expression instead of after the brackets (#872)
755 - `blackd` now returns the version of _Black_ in the response headers (#1013)
757 - `blackd` can now output the diff of formats on source code when the `X-Diff` header is
762 - new option `--target-version` to control which Python versions _Black_-formatted code
765 - deprecated `--py36` (use `--target-version=py36` instead) (#724)
767 - _Black_ no longer normalizes numeric literals to include `_` separators (#696)
769 - long `del` statements are now split into multiple lines (#698)
771 - type comments are no longer mangled in function signatures
773 - improved performance of formatting deeply nested data structures (#509)
775 - _Black_ now properly formats multiple files in parallel on Windows (#632)
777 - _Black_ now creates cache files atomically which allows it to be used in parallel
778 pipelines (like `xargs -P8`) (#673)
780 - _Black_ now correctly indents comments in files that were previously formatted with
783 - `blackd` now supports CORS (#622)
787 - numeric literals are now formatted by _Black_ (#452, #461, #464, #469):
789 - numeric literals are normalized to include `_` separators on Python 3.6+ code
791 - added `--skip-numeric-underscore-normalization` to disable the above behavior and
792 leave numeric underscores as they were in the input
794 - code with `_` in numeric literals is recognized as Python 3.6+
796 - most letters in numeric literals are lowercased (e.g., in `1e10`, `0x01`)
798 - hexadecimal digits are always uppercased (e.g. `0xBADC0DE`)
800 - added `blackd`, see
801 [its documentation](https://github.com/psf/black/blob/18.9b0/README.md#blackd) for
804 - adjacent string literals are now correctly split into multiple lines (#463)
806 - trailing comma is now added to single imports that don't fit on a line (#250)
808 - cache is now populated when `--check` is successful for a file which speeds up
809 consecutive checks of properly formatted unmodified files (#448)
811 - whitespace at the beginning of the file is now removed (#399)
813 - fixed mangling [pweave](http://mpastell.com/pweave/) and
814 [Spyder IDE](https://www.spyder-ide.org/) special comments (#532)
816 - fixed unstable formatting when unpacking big tuples (#267)
818 - fixed parsing of `__future__` imports with renames (#389)
820 - fixed scope of `# fmt: off` when directly preceding `yield` and other nodes (#385)
822 - fixed formatting of lambda expressions with default arguments (#468)
824 - fixed `async for` statements: _Black_ no longer breaks them into separate lines (#372)
826 - note: the Vim plugin stopped registering `,=` as a default chord as it turned out to
831 - hotfix: don't freeze when multiple comments directly precede `# fmt: off` (#371)
835 - typing stub files (`.pyi`) now have blank lines added after constants (#340)
837 - `# fmt: off` and `# fmt: on` are now much more dependable:
839 - they now work also within bracket pairs (#329)
841 - they now correctly work across function/class boundaries (#335)
843 - they now work when an indentation block starts with empty lines or misaligned
846 - made Click not fail on invalid environments; note that Click is right but the
847 likelihood we'll need to access non-ASCII file paths when dealing with Python source
850 - fixed improper formatting of f-strings with quotes inside interpolated expressions
853 - fixed unnecessary slowdown when long list literals where found in a file
855 - fixed unnecessary slowdown on AST nodes with very many siblings
857 - fixed cannibalizing backslashes during string normalization
859 - fixed a crash due to symbolic links pointing outside of the project directory (#338)
863 - added `--config` (#65)
865 - added `-h` equivalent to `--help` (#316)
867 - fixed improper unmodified file caching when `-S` was used
869 - fixed extra space in string unpacking (#305)
871 - fixed formatting of empty triple quoted strings (#313)
873 - fixed unnecessary slowdown in comment placement calculation on lines without comments
877 - hotfix: don't output human-facing information on stdout (#299)
879 - hotfix: don't output cake emoji on non-zero return code (#300)
883 - added `--include` and `--exclude` (#270)
885 - added `--skip-string-normalization` (#118)
887 - added `--verbose` (#283)
889 - the header output in `--diff` now actually conforms to the unified diff spec
891 - fixed long trivial assignments being wrapped in unnecessary parentheses (#273)
893 - fixed unnecessary parentheses when a line contained multiline strings (#232)
895 - fixed stdin handling not working correctly if an old version of Click was used (#276)
897 - _Black_ now preserves line endings when formatting a file in place (#258)
901 - added `--pyi` (#249)
903 - added `--py36` (#249)
905 - Python grammar pickle caches are stored with the formatting caches, making _Black_
906 work in environments where site-packages is not user-writable (#192)
908 - _Black_ now enforces a PEP 257 empty line after a class-level docstring (and/or
909 fields) and the first method
911 - fixed invalid code produced when standalone comments were present in a trailer that
912 was omitted from line splitting on a large expression (#237)
914 - fixed optional parentheses being removed within `# fmt: off` sections (#224)
916 - fixed invalid code produced when stars in very long imports were incorrectly wrapped
917 in optional parentheses (#234)
919 - fixed unstable formatting when inline comments were moved around in a trailer that was
920 omitted from line splitting on a large expression (#238)
922 - fixed extra empty line between a class declaration and the first method if no class
923 docstring or fields are present (#219)
925 - fixed extra empty line between a function signature and an inner function or inner
930 - call chains are now formatted according to the
931 [fluent interfaces](https://en.wikipedia.org/wiki/Fluent_interface) style (#67)
933 - data structure literals (tuples, lists, dictionaries, and sets) are now also always
934 exploded like imports when they don't fit in a single line (#152)
936 - slices are now formatted according to PEP 8 (#178)
938 - parentheses are now also managed automatically on the right-hand side of assignments
939 and return statements (#140)
941 - math operators now use their respective priorities for delimiting multiline
944 - optional parentheses are now omitted on expressions that start or end with a bracket
945 and only contain a single operator (#177)
947 - empty parentheses in a class definition are now removed (#145, #180)
949 - string prefixes are now standardized to lowercase and `u` is removed on Python 3.6+
950 only code and Python 2.7+ code with the `unicode_literals` future import (#188, #198,
953 - typing stub files (`.pyi`) are now formatted in a style that is consistent with PEP
956 - progress when reformatting many files is now reported incrementally
958 - fixed trailers (content with brackets) being unnecessarily exploded into their own
959 lines after a dedented closing bracket (#119)
961 - fixed an invalid trailing comma sometimes left in imports (#185)
963 - fixed non-deterministic formatting when multiple pairs of removable parentheses were
966 - fixed multiline strings being unnecessarily wrapped in optional parentheses in long
969 - fixed not splitting long from-imports with only a single name
971 - fixed Python 3.6+ file discovery by also looking at function calls with unpacking.
972 This fixed non-deterministic formatting if trailing commas where used both in function
973 signatures with stars and function calls with stars but the former would be
974 reformatted to a single line.
976 - fixed crash on dealing with optional parentheses (#193)
978 - fixed "is", "is not", "in", and "not in" not considered operators for splitting
981 - fixed crash when dead symlinks where encountered
985 - don't populate the cache on `--check` (#175)
989 - added a "cache"; files already reformatted that haven't changed on disk won't be
990 reformatted again (#109)
992 - `--check` and `--diff` are no longer mutually exclusive (#149)
994 - generalized star expression handling, including double stars; this fixes
995 multiplication making expressions "unsafe" for trailing commas (#132)
997 - _Black_ no longer enforces putting empty lines behind control flow statements (#90)
999 - _Black_ now splits imports like "Mode 3 + trailing comma" of isort (#127)
1001 - fixed comment indentation when a standalone comment closes a block (#16, #32)
1003 - fixed standalone comments receiving extra empty lines if immediately preceding a
1004 class, def, or decorator (#56, #154)
1006 - fixed `--diff` not showing entire path (#130)
1008 - fixed parsing of complex expressions after star and double stars in function calls
1011 - fixed invalid splitting on comma in lambda arguments (#133)
1013 - fixed missing splits of ternary expressions (#141)
1017 - fixed parsing of unaligned standalone comments (#99, #112)
1019 - fixed placement of dictionary unpacking inside dictionary literals (#111)
1021 - Vim plugin now works on Windows, too
1023 - fixed unstable formatting when encountering unnecessarily escaped quotes in a string
1028 - added `--quiet` (#78)
1030 - added automatic parentheses management (#4)
1032 - added [pre-commit](https://pre-commit.com) integration (#103, #104)
1034 - fixed reporting on `--check` with multiple files (#101, #102)
1036 - fixed removing backslash escapes from raw strings (#100, #105)
1040 - added `--diff` (#87)
1042 - add line breaks before all delimiters, except in cases like commas, to better comply
1045 - standardize string literals to use double quotes (almost) everywhere (#75)
1047 - fixed handling of standalone comments within nested bracketed expressions; _Black_
1048 will no longer produce super long lines or put all standalone comments at the end of
1049 the expression (#22)
1051 - fixed 18.3a4 regression: don't crash and burn on empty lines with trailing whitespace
1054 - fixed 18.3a4 regression: `# yapf: disable` usage as trailing comment would cause
1055 _Black_ to not emit the rest of the file (#95)
1057 - when CTRL+C is pressed while formatting many files, _Black_ no longer freaks out with
1058 a flurry of asyncio-related exceptions
1060 - only allow up to two empty lines on module level and only single empty lines within
1065 - `# fmt: off` and `# fmt: on` are implemented (#5)
1067 - automatic detection of deprecated Python 2 forms of print statements and exec
1068 statements in the formatted file (#49)
1070 - use proper spaces for complex expressions in default values of typed function
1073 - only return exit code 1 when --check is used (#50)
1075 - don't remove single trailing commas from square bracket indexing (#59)
1077 - don't omit whitespace if the previous factor leaf wasn't a math operator (#55)
1079 - omit extra space in kwarg unpacking if it's the first argument (#46)
1081 - omit extra space in
1082 [Sphinx auto-attribute comments](http://www.sphinx-doc.org/en/stable/ext/autodoc.html#directive-autoattribute)
1087 - don't remove single empty lines outside of bracketed expressions (#19)
1089 - added ability to pipe formatting from stdin to stdin (#25)
1091 - restored ability to format code with legacy usage of `async` as a name (#20, #42)
1093 - even better handling of numpy-style array indexing (#33, again)
1097 - changed positioning of binary operators to occur at beginning of lines instead of at
1099 [a recent change to PEP 8](https://github.com/python/peps/commit/c59c4376ad233a62ca4b3a6060c81368bd21e85b)
1102 - ignore empty bracket pairs while splitting. This avoids very weirdly looking
1103 formattings (#34, #35)
1105 - remove a trailing comma if there is a single argument to a call
1107 - if top level functions were separated by a comment, don't put four empty lines after
1110 - fixed unstable formatting of newlines with imports
1112 - fixed unintentional folding of post scriptum standalone comments into last statement
1113 if it was a simple statement (#18, #28)
1115 - fixed missing space in numpy-style array indexing (#33)
1117 - fixed spurious space after star-based unary expressions (#31)
1123 - only put trailing commas in function signatures and calls if it's safe to do so. If
1124 the file is Python 3.6+ it's always safe, otherwise only safe if there are no `*args`
1125 or `**kwargs` used in the signature or call. (#8)
1127 - fixed invalid spacing of dots in relative imports (#6, #13)
1129 - fixed invalid splitting after comma on unpacked variables in for-loops (#23)
1131 - fixed spurious space in parenthesized set expressions (#7)
1133 - fixed spurious space after opening parentheses and in default arguments (#14, #17)
1135 - fixed spurious space after unary operators when the operand was a complex expression
1140 - first published version, Happy 🍰 Day 2018!
1144 - date-versioned (see: <https://calver.org/>)