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 -->
25 - Do not format `__pypackages__` directories by default (#2836)
26 - Add support for specifying stable version with `--required-version` (#2832).
27 - Avoid crashing when the user has no homedir (#2814)
28 - Avoid crashing when md5 is not available (#2905)
32 <!-- Major changes to documentation and policies. Small docs changes
33 don't need a changelog entry. -->
37 <!-- For example, Docker, GitHub Actions, pre-commit, editors -->
41 <!-- Changes to Black's terminal output and error messages -->
43 - In verbose, mode, log when _Black_ is using user-level config (#2861)
47 <!-- Changes to how Black is packaged, such as dependency requirements -->
51 <!-- Changes to the parser or to version autodetection -->
55 <!-- Changes that improve Black's performance. -->
59 At long last, _Black_ is no longer a beta product! This is the first non-beta release
60 and the first release covered by our new
61 [stability policy](https://black.readthedocs.io/en/stable/the_black_code_style/index.html#stability-policy).
65 - **Remove Python 2 support** (#2740)
66 - Introduce the `--preview` flag (#2752)
70 - Deprecate `--experimental-string-processing` and move the functionality under
72 - For stubs, one blank line between class attributes and methods is now kept if there's
73 at least one pre-existing blank line (#2736)
74 - Black now normalizes string prefix order (#2297)
75 - Remove spaces around power operators if both operands are simple (#2726)
76 - Work around bug that causes unstable formatting in some cases in the presence of the
77 magic trailing comma (#2807)
78 - Use parentheses for attribute access on decimal float and int literals (#2799)
79 - Don't add whitespace for attribute access on hexadecimal, binary, octal, and complex
81 - Treat blank lines in stubs the same inside top-level `if` statements (#2820)
82 - Fix unstable formatting with semicolons and arithmetic expressions (#2817)
83 - Fix unstable formatting around magic trailing comma (#2572)
87 - Fix mapping cases that contain as-expressions, like `case {"key": 1 | 2 as password}`
89 - Fix cases that contain multiple top-level as-expressions, like `case 1 as a, 2 as b`
91 - Fix call patterns that contain as-expressions with keyword arguments, like
92 `case Foo(bar=baz as quux)` (#2749)
93 - Tuple unpacking on `return` and `yield` constructs now implies 3.8+ (#2700)
94 - Unparenthesized tuples on annotated assignments (e.g
95 `values: Tuple[int, ...] = 1, 2, 3`) now implies 3.8+ (#2708)
96 - Fix handling of standalone `match()` or `case()` when there is a trailing newline or a
97 comment inside of the parentheses. (#2760)
98 - `from __future__ import annotations` statement now implies Python 3.7+ (#2690)
102 - Speed-up the new backtracking parser about 4X in general (enabled when
103 `--target-version` is set to 3.10 and higher). (#2728)
104 - _Black_ is now compiled with [mypyc](https://github.com/mypyc/mypyc) for an overall 2x
105 speed-up. 64-bit Windows, MacOS, and Linux (not including musl) are supported. (#1009,
110 - Do not accept bare carriage return line endings in pyproject.toml (#2408)
111 - Add configuration option (`python-cell-magics`) to format cells with custom magics in
112 Jupyter Notebooks (#2744)
113 - Allow setting custom cache directory on all platforms with environment variable
114 `BLACK_CACHE_DIR` (#2739).
115 - Enable Python 3.10+ by default, without any extra need to specify
116 `--target-version=py310`. (#2758)
117 - Make passing `SRC` or `--code` mandatory and mutually exclusive (#2804)
121 - Improve error message for invalid regular expression (#2678)
122 - Improve error message when parsing fails during AST safety check by embedding the
123 underlying SyntaxError (#2693)
124 - No longer color diff headers white as it's unreadable in light themed terminals
126 - Text coloring added in the final statistics (#2712)
127 - Verbose mode also now describes how a project root was discovered and which paths will
128 be formatted. (#2526)
132 - All upper version bounds on dependencies have been removed (#2718)
133 - `typing-extensions` is no longer a required dependency in Python 3.10+ (#2772)
134 - Set `click` lower bound to `8.0.0` (#2791)
138 - Update GitHub action to support containerized runs (#2748)
142 - Change protocol in pip installation instructions to `https://` (#2761)
143 - Change HTML theme to Furo primarily for its responsive design and mobile support
145 - Deprecate the `black-primer` tool (#2809)
146 - Document Python support policy (#2819)
152 - Fix determination of f-string expression spans (#2654)
153 - Fix bad formatting of error messages about EOF in multi-line statements (#2343)
154 - Functions and classes in blocks now have more consistent surrounding spacing (#2472)
156 #### Jupyter Notebook support
158 - Cell magics are now only processed if they are known Python cell magics. Earlier, all
159 cell magics were tokenized, leading to possible indentation errors e.g. with
160 `%%writefile`. (#2630)
161 - Fix assignment to environment variables in Jupyter Notebooks (#2642)
163 #### Python 3.10 support
165 - Point users to using `--target-version py310` if we detect 3.10-only syntax (#2668)
166 - Fix `match` statements with open sequence subjects, like `match a, b:` or
167 `match a, *b:` (#2639) (#2659)
168 - Fix `match`/`case` statements that contain `match`/`case` soft keywords multiple
169 times, like `match re.match()` (#2661)
170 - Fix `case` statements with an inline body (#2665)
171 - Fix styling of starred expressions inside `match` subject (#2667)
172 - Fix parser error location on invalid syntax in a `match` statement (#2649)
173 - Fix Python 3.10 support on platforms without ProcessPoolExecutor (#2631)
174 - Improve parsing performance on code that uses `match` under `--target-version py310`
179 - Remove dependency on `regex` (#2644) (#2663)
185 - Bumped regex version minimum to 2021.4.4 to fix Pattern class usage (#2621)
191 - Warn about Python 2 deprecation in more cases by improving Python 2 only syntax
193 - Add experimental PyPy support (#2559)
194 - Add partial support for the match statement. As it's experimental, it's only enabled
195 when `--target-version py310` is explicitly specified (#2586)
196 - Add support for parenthesized with (#2586)
197 - Declare support for Python 3.10 for running Black (#2562)
201 - Fixed vim plugin with Python 3.10 by removing deprecated distutils import (#2610)
202 - The vim plugin now parses `skip_magic_trailing_comma` from pyproject.toml (#2613)
208 - Document stability policy, that will apply for non-beta releases (#2529)
209 - Add new `--workers` parameter (#2514)
210 - Fixed feature detection for positional-only arguments in lambdas (#2532)
211 - Bumped typed-ast version minimum to 1.4.3 for 3.10 compatibility (#2519)
212 - Fixed a Python 3.10 compatibility issue where the loop argument was still being passed
213 even though it has been removed (#2580)
214 - Deprecate Python 2 formatting support (#2523)
218 - Remove dependency on aiohttp-cors (#2500)
219 - Bump required aiohttp version to 3.7.4 (#2509)
223 - Add primer support for --projects (#2555)
224 - Print primer summary after individual failures (#2570)
228 - Allow to pass `target_version` in the vim plugin (#1319)
229 - Install build tools in docker file and use multi-stage build to keep the image size
236 - Fix missing modules in self-contained binaries (#2466)
237 - Fix missing toml extra used during installation (#2475)
243 - Add support for formatting Jupyter Notebook files (#2357)
244 - Move from `appdirs` dependency to `platformdirs` (#2375)
245 - Present a more user-friendly error if .gitignore is invalid (#2414)
246 - The failsafe for accidentally added backslashes in f-string expressions has been
247 hardened to handle more edge cases during quote normalization (#2437)
248 - Avoid changing a function return type annotation's type to a tuple by adding a
249 trailing comma (#2384)
250 - Parsing support has been added for unparenthesized walruses in set literals, set
251 comprehensions, and indices (#2447).
252 - Pin `setuptools-scm` build-time dependency version (#2457)
253 - Exclude typing-extensions version 3.10.0.1 due to it being broken on Python 3.10
258 - Replace sys.exit(-1) with raise ImportError as it plays more nicely with tools that
259 scan installed packages (#2440)
263 - The provided pre-commit hooks no longer specify `language_version` to avoid overriding
264 `default_language_version` (#2430)
270 - Configuration files using TOML features higher than spec v0.5.0 are now supported
272 - Add primer support and test for code piped into black via STDIN (#2315)
273 - Fix internal error when `FORCE_OPTIONAL_PARENTHESES` feature is enabled (#2332)
274 - Accept empty stdin (#2346)
275 - Provide a more useful error when parsing fails during AST safety checks (#2304)
279 - Add new `latest_release` tag automation to follow latest black release on docker
284 - The vim plugin now searches upwards from the directory containing the current buffer
285 instead of the current working directory for pyproject.toml. (#1871)
286 - The vim plugin now reads the correct string normalization option in pyproject.toml
288 - The vim plugin no longer crashes Black when there's boolean values in pyproject.toml
295 - Fix failure caused by `fmt: skip` and indentation (#2281)
296 - Account for += assignment when deciding whether to split string (#2312)
297 - Correct max string length calculation when there are string operators (#2292)
298 - Fixed option usage when using the `--code` flag (#2259)
299 - Do not call `uvloop.install()` when _Black_ is used as a library (#2303)
300 - Added `--required-version` option to require a specific version to be running (#2300)
301 - Fix incorrect custom breakpoint indices when string group contains fake f-strings
303 - Fix regression where `R` prefixes would be lowercased for docstrings (#2285)
304 - Fix handling of named escapes (`\N{...}`) when `--experimental-string-processing` is
309 - The official Black action now supports choosing what version to use, and supports the
310 major 3 OSes. (#1940)
316 - A space is no longer inserted into empty docstrings (#2249)
317 - Fix handling of .gitignore files containing non-ASCII characters on Windows (#2229)
318 - Respect `.gitignore` files in all levels, not only `root/.gitignore` file (apply
319 `.gitignore` rules like `git` does) (#2225)
320 - Restored compatibility with Click 8.0 on Python 3.6 when LANG=C used (#2227)
321 - Add extra uvloop install + import support if in python env (#2258)
322 - Fix --experimental-string-processing crash when matching parens are not found (#2283)
323 - Make sure to split lines that start with a string operator (#2286)
324 - Fix regular expression that black uses to identify f-expressions (#2287)
328 - Add a lower bound for the `aiohttp-cors` dependency. Only 0.4.0 or higher is
333 - Release self-contained x86_64 MacOS binaries as part of the GitHub release pipeline
335 - Always build binaries with the latest available Python (#2260)
339 - Add discussion of magic comments to FAQ page (#2272)
340 - `--experimental-string-processing` will be enabled by default in the future (#2273)
341 - Fix typos discovered by codespell (#2228)
342 - Fix Vim plugin installation instructions. (#2235)
343 - Add new Frequently Asked Questions page (#2247)
344 - Fix encoding + symlink issues preventing proper build on Windows (#2262)
350 - Refactor `src/black/__init__.py` into many files (#2206)
354 - Replaced all remaining references to the
355 [`master`](https://github.com/psf/black/tree/main) branch with the
356 [`main`](https://github.com/psf/black/tree/main) branch. Some additional changes in
357 the source code were also made. (#2210)
358 - Sigificantly reorganized the documentation to make much more sense. Check them out by
359 heading over to [the stable docs on RTD](https://black.readthedocs.io/en/stable/).
366 - Set `--pyi` mode if `--stdin-filename` ends in `.pyi` (#2169)
367 - Stop detecting target version as Python 3.9+ with pre-PEP-614 decorators that are
368 being called but with no arguments (#2182)
372 - Add `--no-diff` to black-primer to suppress formatting changes (#2187)
378 - Fix crash if the user configuration directory is inaccessible. (#2158)
381 [circumstances](https://github.com/psf/black/blob/master/docs/the_black_code_style.md#pragmatism)
382 in which _Black_ may change the AST (#2159)
384 - Allow `.gitignore` rules to be overridden by specifying `exclude` in `pyproject.toml`
385 or on the command line. (#2170)
389 - Install `primer.json` (used by `black-primer` by default) with black. (#2154)
395 - Fix crash on docstrings ending with "\\ ". (#2142)
397 - Fix crash when atypical whitespace is cleaned out of dostrings (#2120)
399 - Reflect the `--skip-magic-trailing-comma` and `--experimental-string-processing` flags
400 in the name of the cache file. Without this fix, changes in these flags would not take
401 effect if the cache had already been populated. (#2131)
403 - Don't remove necessary parentheses from assignment expression containing assert /
404 return statements. (#2143)
408 - Bump pathspec to >= 0.8.1 to solve invalid .gitignore exclusion handling
414 - Fixed a rare but annoying formatting instability created by the combination of
415 optional trailing commas inserted by `Black` and optional parentheses looking at
416 pre-existing "magic" trailing commas. This fixes issue #1629 and all of its many many
419 - `Black` now processes one-line docstrings by stripping leading and trailing spaces,
420 and adding a padding space when needed to break up """". (#1740)
422 - `Black` now cleans up leading non-breaking spaces in comments (#2092)
424 - `Black` now respects `--skip-string-normalization` when normalizing multiline
425 docstring quotes (#1637)
427 - `Black` no longer removes all empty lines between non-function code and decorators
428 when formatting typing stubs. Now `Black` enforces a single empty line. (#1646)
430 - `Black` no longer adds an incorrect space after a parenthesized assignment expression
431 in if/while statements (#1655)
433 - Added `--skip-magic-trailing-comma` / `-C` to avoid using trailing commas as a reason
434 to split lines (#1824)
436 - fixed a crash when PWD=/ on POSIX (#1631)
438 - fixed "I/O operation on closed file" when using --diff (#1664)
440 - Prevent coloured diff output being interleaved with multiple files (#1673)
442 - Added support for PEP 614 relaxed decorator syntax on python 3.9 (#1711)
444 - Added parsing support for unparenthesized tuples and yield expressions in annotated
447 - added `--extend-exclude` argument (PR #2005)
449 - speed up caching by avoiding pathlib (#1950)
451 - `--diff` correctly indicates when a file doesn't end in a newline (#1662)
453 - Added `--stdin-filename` argument to allow stdin to respect `--force-exclude` rules
456 - Lines ending with `fmt: skip` will now be not formatted (#1800)
458 - PR #2053: Black no longer relies on typed-ast for Python 3.8 and higher
460 - PR #2053: Python 2 support is now optional, install with
461 `python3 -m pip install black[python2]` to maintain support.
463 - Exclude `venv` directory by default (#1683)
465 - Fixed "Black produced code that is not equivalent to the source" when formatting
466 Python 2 docstrings (#2037)
470 - Self-contained native _Black_ binaries are now provided for releases via GitHub
477 - explicitly depend on Click 7.1.2 or newer as `Black` no longer works with versions
484 - re-implemented support for explicit trailing commas: now it works consistently within
485 any bracket pair, including nested structures (#1288 and duplicates)
487 - `Black` now reindents docstrings when reindenting code around it (#1053)
489 - `Black` now shows colored diffs (#1266)
491 - `Black` is now packaged using 'py3' tagged wheels (#1388)
493 - `Black` now supports Python 3.8 code, e.g. star expressions in return statements
496 - `Black` no longer normalizes capital R-string prefixes as those have a
497 community-accepted meaning (#1244)
499 - `Black` now uses exit code 2 when specified configuration file doesn't exit (#1361)
501 - `Black` now works on AWS Lambda (#1141)
503 - added `--force-exclude` argument (#1032)
505 - removed deprecated `--py36` option (#1236)
507 - fixed `--diff` output when EOF is encountered (#526)
509 - fixed `# fmt: off` handling around decorators (#560)
511 - fixed unstable formatting with some `# type: ignore` comments (#1113)
513 - fixed invalid removal on organizing brackets followed by indexing (#1575)
515 - introduced `black-primer`, a CI tool that allows us to run regression tests against
516 existing open source users of Black (#1402)
518 - introduced property-based fuzzing to our test suite based on Hypothesis and
519 Hypothersmith (#1566)
521 - implemented experimental and disabled by default long string rewrapping (#1132),
522 hidden under a `--experimental-string-processing` flag while it's being worked on;
523 this is an undocumented and unsupported feature, you lose Internet points for
524 depending on it (#1609)
528 - prefer virtualenv packages over global packages (#1383)
532 - added support for PEP 572 assignment expressions (#711)
534 - added support for PEP 570 positional-only arguments (#943)
536 - added support for async generators (#593)
538 - added support for pre-splitting collections by putting an explicit trailing comma
541 - added `black -c` as a way to format code passed from the command line (#761)
543 - --safe now works with Python 2 code (#840)
545 - fixed grammar selection for Python 2-specific code (#765)
547 - fixed feature detection for trailing commas in function definitions and call sites
550 - `# fmt: off`/`# fmt: on` comment pairs placed multiple times within the same block of
551 code now behave correctly (#1005)
553 - _Black_ no longer crashes on Windows machines with more than 61 cores (#838)
555 - _Black_ no longer crashes on standalone comments prepended with a backslash (#767)
557 - _Black_ no longer crashes on `from` ... `import` blocks with comments (#829)
559 - _Black_ no longer crashes on Python 3.7 on some platform configurations (#494)
561 - _Black_ no longer fails on comments in from-imports (#671)
563 - _Black_ no longer fails when the file starts with a backslash (#922)
565 - _Black_ no longer merges regular comments with type comments (#1027)
567 - _Black_ no longer splits long lines that contain type comments (#997)
569 - removed unnecessary parentheses around `yield` expressions (#834)
571 - added parentheses around long tuples in unpacking assignments (#832)
573 - added parentheses around complex powers when they are prefixed by a unary operator
576 - fixed bug that led _Black_ format some code with a line length target of 1 (#762)
578 - _Black_ no longer introduces quotes in f-string subexpressions on string boundaries
581 - if _Black_ puts parenthesis around a single expression, it moves comments to the
582 wrapped expression instead of after the brackets (#872)
584 - `blackd` now returns the version of _Black_ in the response headers (#1013)
586 - `blackd` can now output the diff of formats on source code when the `X-Diff` header is
591 - new option `--target-version` to control which Python versions _Black_-formatted code
594 - deprecated `--py36` (use `--target-version=py36` instead) (#724)
596 - _Black_ no longer normalizes numeric literals to include `_` separators (#696)
598 - long `del` statements are now split into multiple lines (#698)
600 - type comments are no longer mangled in function signatures
602 - improved performance of formatting deeply nested data structures (#509)
604 - _Black_ now properly formats multiple files in parallel on Windows (#632)
606 - _Black_ now creates cache files atomically which allows it to be used in parallel
607 pipelines (like `xargs -P8`) (#673)
609 - _Black_ now correctly indents comments in files that were previously formatted with
612 - `blackd` now supports CORS (#622)
616 - numeric literals are now formatted by _Black_ (#452, #461, #464, #469):
618 - numeric literals are normalized to include `_` separators on Python 3.6+ code
620 - added `--skip-numeric-underscore-normalization` to disable the above behavior and
621 leave numeric underscores as they were in the input
623 - code with `_` in numeric literals is recognized as Python 3.6+
625 - most letters in numeric literals are lowercased (e.g., in `1e10`, `0x01`)
627 - hexadecimal digits are always uppercased (e.g. `0xBADC0DE`)
629 - added `blackd`, see
630 [its documentation](https://github.com/psf/black/blob/18.9b0/README.md#blackd) for
633 - adjacent string literals are now correctly split into multiple lines (#463)
635 - trailing comma is now added to single imports that don't fit on a line (#250)
637 - cache is now populated when `--check` is successful for a file which speeds up
638 consecutive checks of properly formatted unmodified files (#448)
640 - whitespace at the beginning of the file is now removed (#399)
642 - fixed mangling [pweave](http://mpastell.com/pweave/) and
643 [Spyder IDE](https://www.spyder-ide.org/) special comments (#532)
645 - fixed unstable formatting when unpacking big tuples (#267)
647 - fixed parsing of `__future__` imports with renames (#389)
649 - fixed scope of `# fmt: off` when directly preceding `yield` and other nodes (#385)
651 - fixed formatting of lambda expressions with default arguments (#468)
653 - fixed `async for` statements: _Black_ no longer breaks them into separate lines (#372)
655 - note: the Vim plugin stopped registering `,=` as a default chord as it turned out to
660 - hotfix: don't freeze when multiple comments directly precede `# fmt: off` (#371)
664 - typing stub files (`.pyi`) now have blank lines added after constants (#340)
666 - `# fmt: off` and `# fmt: on` are now much more dependable:
668 - they now work also within bracket pairs (#329)
670 - they now correctly work across function/class boundaries (#335)
672 - they now work when an indentation block starts with empty lines or misaligned
675 - made Click not fail on invalid environments; note that Click is right but the
676 likelihood we'll need to access non-ASCII file paths when dealing with Python source
679 - fixed improper formatting of f-strings with quotes inside interpolated expressions
682 - fixed unnecessary slowdown when long list literals where found in a file
684 - fixed unnecessary slowdown on AST nodes with very many siblings
686 - fixed cannibalizing backslashes during string normalization
688 - fixed a crash due to symbolic links pointing outside of the project directory (#338)
692 - added `--config` (#65)
694 - added `-h` equivalent to `--help` (#316)
696 - fixed improper unmodified file caching when `-S` was used
698 - fixed extra space in string unpacking (#305)
700 - fixed formatting of empty triple quoted strings (#313)
702 - fixed unnecessary slowdown in comment placement calculation on lines without comments
706 - hotfix: don't output human-facing information on stdout (#299)
708 - hotfix: don't output cake emoji on non-zero return code (#300)
712 - added `--include` and `--exclude` (#270)
714 - added `--skip-string-normalization` (#118)
716 - added `--verbose` (#283)
718 - the header output in `--diff` now actually conforms to the unified diff spec
720 - fixed long trivial assignments being wrapped in unnecessary parentheses (#273)
722 - fixed unnecessary parentheses when a line contained multiline strings (#232)
724 - fixed stdin handling not working correctly if an old version of Click was used (#276)
726 - _Black_ now preserves line endings when formatting a file in place (#258)
730 - added `--pyi` (#249)
732 - added `--py36` (#249)
734 - Python grammar pickle caches are stored with the formatting caches, making _Black_
735 work in environments where site-packages is not user-writable (#192)
737 - _Black_ now enforces a PEP 257 empty line after a class-level docstring (and/or
738 fields) and the first method
740 - fixed invalid code produced when standalone comments were present in a trailer that
741 was omitted from line splitting on a large expression (#237)
743 - fixed optional parentheses being removed within `# fmt: off` sections (#224)
745 - fixed invalid code produced when stars in very long imports were incorrectly wrapped
746 in optional parentheses (#234)
748 - fixed unstable formatting when inline comments were moved around in a trailer that was
749 omitted from line splitting on a large expression (#238)
751 - fixed extra empty line between a class declaration and the first method if no class
752 docstring or fields are present (#219)
754 - fixed extra empty line between a function signature and an inner function or inner
759 - call chains are now formatted according to the
760 [fluent interfaces](https://en.wikipedia.org/wiki/Fluent_interface) style (#67)
762 - data structure literals (tuples, lists, dictionaries, and sets) are now also always
763 exploded like imports when they don't fit in a single line (#152)
765 - slices are now formatted according to PEP 8 (#178)
767 - parentheses are now also managed automatically on the right-hand side of assignments
768 and return statements (#140)
770 - math operators now use their respective priorities for delimiting multiline
773 - optional parentheses are now omitted on expressions that start or end with a bracket
774 and only contain a single operator (#177)
776 - empty parentheses in a class definition are now removed (#145, #180)
778 - string prefixes are now standardized to lowercase and `u` is removed on Python 3.6+
779 only code and Python 2.7+ code with the `unicode_literals` future import (#188, #198,
782 - typing stub files (`.pyi`) are now formatted in a style that is consistent with PEP
785 - progress when reformatting many files is now reported incrementally
787 - fixed trailers (content with brackets) being unnecessarily exploded into their own
788 lines after a dedented closing bracket (#119)
790 - fixed an invalid trailing comma sometimes left in imports (#185)
792 - fixed non-deterministic formatting when multiple pairs of removable parentheses were
795 - fixed multiline strings being unnecessarily wrapped in optional parentheses in long
798 - fixed not splitting long from-imports with only a single name
800 - fixed Python 3.6+ file discovery by also looking at function calls with unpacking.
801 This fixed non-deterministic formatting if trailing commas where used both in function
802 signatures with stars and function calls with stars but the former would be
803 reformatted to a single line.
805 - fixed crash on dealing with optional parentheses (#193)
807 - fixed "is", "is not", "in", and "not in" not considered operators for splitting
810 - fixed crash when dead symlinks where encountered
814 - don't populate the cache on `--check` (#175)
818 - added a "cache"; files already reformatted that haven't changed on disk won't be
819 reformatted again (#109)
821 - `--check` and `--diff` are no longer mutually exclusive (#149)
823 - generalized star expression handling, including double stars; this fixes
824 multiplication making expressions "unsafe" for trailing commas (#132)
826 - _Black_ no longer enforces putting empty lines behind control flow statements (#90)
828 - _Black_ now splits imports like "Mode 3 + trailing comma" of isort (#127)
830 - fixed comment indentation when a standalone comment closes a block (#16, #32)
832 - fixed standalone comments receiving extra empty lines if immediately preceding a
833 class, def, or decorator (#56, #154)
835 - fixed `--diff` not showing entire path (#130)
837 - fixed parsing of complex expressions after star and double stars in function calls
840 - fixed invalid splitting on comma in lambda arguments (#133)
842 - fixed missing splits of ternary expressions (#141)
846 - fixed parsing of unaligned standalone comments (#99, #112)
848 - fixed placement of dictionary unpacking inside dictionary literals (#111)
850 - Vim plugin now works on Windows, too
852 - fixed unstable formatting when encountering unnecessarily escaped quotes in a string
857 - added `--quiet` (#78)
859 - added automatic parentheses management (#4)
861 - added [pre-commit](https://pre-commit.com) integration (#103, #104)
863 - fixed reporting on `--check` with multiple files (#101, #102)
865 - fixed removing backslash escapes from raw strings (#100, #105)
869 - added `--diff` (#87)
871 - add line breaks before all delimiters, except in cases like commas, to better comply
874 - standardize string literals to use double quotes (almost) everywhere (#75)
876 - fixed handling of standalone comments within nested bracketed expressions; _Black_
877 will no longer produce super long lines or put all standalone comments at the end of
880 - fixed 18.3a4 regression: don't crash and burn on empty lines with trailing whitespace
883 - fixed 18.3a4 regression: `# yapf: disable` usage as trailing comment would cause
884 _Black_ to not emit the rest of the file (#95)
886 - when CTRL+C is pressed while formatting many files, _Black_ no longer freaks out with
887 a flurry of asyncio-related exceptions
889 - only allow up to two empty lines on module level and only single empty lines within
894 - `# fmt: off` and `# fmt: on` are implemented (#5)
896 - automatic detection of deprecated Python 2 forms of print statements and exec
897 statements in the formatted file (#49)
899 - use proper spaces for complex expressions in default values of typed function
902 - only return exit code 1 when --check is used (#50)
904 - don't remove single trailing commas from square bracket indexing (#59)
906 - don't omit whitespace if the previous factor leaf wasn't a math operator (#55)
908 - omit extra space in kwarg unpacking if it's the first argument (#46)
910 - omit extra space in
911 [Sphinx auto-attribute comments](http://www.sphinx-doc.org/en/stable/ext/autodoc.html#directive-autoattribute)
916 - don't remove single empty lines outside of bracketed expressions (#19)
918 - added ability to pipe formatting from stdin to stdin (#25)
920 - restored ability to format code with legacy usage of `async` as a name (#20, #42)
922 - even better handling of numpy-style array indexing (#33, again)
926 - changed positioning of binary operators to occur at beginning of lines instead of at
928 [a recent change to PEP 8](https://github.com/python/peps/commit/c59c4376ad233a62ca4b3a6060c81368bd21e85b)
931 - ignore empty bracket pairs while splitting. This avoids very weirdly looking
932 formattings (#34, #35)
934 - remove a trailing comma if there is a single argument to a call
936 - if top level functions were separated by a comment, don't put four empty lines after
939 - fixed unstable formatting of newlines with imports
941 - fixed unintentional folding of post scriptum standalone comments into last statement
942 if it was a simple statement (#18, #28)
944 - fixed missing space in numpy-style array indexing (#33)
946 - fixed spurious space after star-based unary expressions (#31)
952 - only put trailing commas in function signatures and calls if it's safe to do so. If
953 the file is Python 3.6+ it's always safe, otherwise only safe if there are no `*args`
954 or `**kwargs` used in the signature or call. (#8)
956 - fixed invalid spacing of dots in relative imports (#6, #13)
958 - fixed invalid splitting after comma on unpacked variables in for-loops (#23)
960 - fixed spurious space in parenthesized set expressions (#7)
962 - fixed spurious space after opening parentheses and in default arguments (#14, #17)
964 - fixed spurious space after unary operators when the operand was a complex expression
969 - first published version, Happy 🍰 Day 2018!
973 - date-versioned (see: <https://calver.org/>)