X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/9d78a5718760db0737904803e4affb8b9ce24fce..73cb6e7734370108742d992d4fe1fa2829f100fd:/README.md?ds=sidebyside diff --git a/README.md b/README.md index 3df8adc..e900d2d 100644 --- a/README.md +++ b/README.md @@ -1,319 +1,225 @@ -# black +![Black Logo](https://raw.githubusercontent.com/psf/black/main/docs/_static/logo2-readme.png) -[![Build Status](https://travis-ci.org/ambv/black.svg?branch=master)](https://travis-ci.org/ambv/black) +

The Uncompromising Code Formatter

-> Any color you like. +

+Actions Status +Actions Status +Documentation Status +Coverage Status +License: MIT +PyPI +Downloads +conda-forge +Code style: black +

+> “Any color you like.” -*Black* is the uncompromising Python code formatter. By using it, you -agree to cease control over minutiae of hand-formatting. In return, -*Black* gives you speed, determinism, and freedom from `pycodestyle` -nagging about formatting. You will save time and mental energy for -more important matters. +_Black_ is the uncompromising Python code formatter. By using it, you agree to cede +control over minutiae of hand-formatting. In return, _Black_ gives you speed, +determinism, and freedom from `pycodestyle` nagging about formatting. You will save time +and mental energy for more important matters. -Blackened code looks the same regardless of the project you're reading. -Formatting becomes transparent after a while and you can focus on the -content instead. +Blackened code looks the same regardless of the project you're reading. Formatting +becomes transparent after a while and you can focus on the content instead. -*Black* makes code review faster by producing the smallest diffs -possible. +_Black_ makes code review faster by producing the smallest diffs possible. +Try it out now using the [Black Playground](https://black.vercel.app). Watch the +[PyCon 2019 talk](https://youtu.be/esZLCuWs_2Y) to learn more. -## NOTE: This is an early pre-release +--- -*Black* can already successfully format itself and the standard library. -It also sports a decent test suite. However, it is still very new. -Things will probably be wonky for a while. This is made explicit by the -"Alpha" trove classifier, as well as by the "a" in the version number. -What this means for you is that **until the formatter becomes stable, -you should expect some formatting to change in the future**. +**[Read the documentation on ReadTheDocs!](https://black.readthedocs.io/en/stable)** -Also, as a temporary safety measure, *Black* will check that the -reformatted code still produces a valid AST that is equivalent to the -original. This slows it down. If you're feeling confident, use -``--fast``. +--- +## Installation and usage -## Usage +### Installation -*Black* can be installed by running `pip install black`. +_Black_ can be installed by running `pip install black`. It requires Python 3.6.2+ to +run. If you want to format Jupyter Notebooks, install with `pip install black[jupyter]`. -``` -black [OPTIONS] [SRC]... - -Options: - -l, --line-length INTEGER Where to wrap around. [default: 88] - --check Don't write back the files, just return the - status. Return code 0 means nothing changed. - Return code 1 means some files were reformatted. - Return code 123 means there was an internal - error. - --fast / --safe If --fast given, skip temporary sanity checks. - [default: --safe] - --version Show the version and exit. - --help Show this message and exit. -``` - - -## The philosophy behind *Black* - -*Black* reformats entire files in place. It is not configurable. It -doesn't take previous formatting into account. It doesn't reformat -blocks that start with `# fmt: off` and end with `# fmt: on`. It also -recognizes [YAPF](https://github.com/google/yapf)'s block comments to -the same effect, as a courtesy for straddling code. +If you can't wait for the latest _hotness_ and want to install from GitHub, use: +`pip install git+https://github.com/psf/black` -### How *Black* formats files +### Usage -*Black* ignores previous formatting and applies uniform horizontal -and vertical whitespace to your code. The rules for horizontal -whitespace are pretty obvious and can be summarized as: do whatever -makes `pycodestyle` happy. +To get started right away with sensible defaults: -As for vertical whitespace, *Black* tries to render one full expression -or simple statement per line. If this fits the allotted line length, -great. -```py3 -# in: -l = [1, - 2, - 3, -] - -# out: -l = [1, 2, 3] +```sh +black {source_file_or_directory} ``` -If not, *Black* will look at the contents of the first outer matching -brackets and put that in a separate indented line. -```py3 -# in: -l = [[n for n in list_bosses()], [n for n in list_employees()]] +You can run _Black_ as a package if running it as a script doesn't work: -# out: -l = [ - [n for n in list_bosses()], [n for n in list_employees()] -] +```sh +python -m black {source_file_or_directory} ``` -If that still doesn't fit the bill, it will decompose the internal -expression further using the same rule, indenting matching brackets -every time. If the contents of the matching brackets pair are -comma-separated (like an argument list, or a dict literal, and so on) -then *Black* will first try to keep them on the same line with the -matching brackets. If that doesn't work, it will put all of them in -separate lines. -```py3 -# in: -def very_important_function(template: str, *variables, *, file: os.PathLike, debug: bool = False): - """Applies `variables` to the `template` and writes to `file`.""" - with open(file, 'w') as f: - ... - -# out: -def very_important_function( - template: str, - *variables, - *, - file: os.PathLike, - debug: bool = False, -): - """Applies `variables` to the `template` and writes to `file`.""" - with open(file, 'w') as f: - ... -``` +Further information can be found in our docs: -You might have noticed that closing brackets are always dedented and -that a trailing comma is always added. Such formatting produces smaller -diffs; when you add or remove an element, it's always just one line. -Also, having the closing bracket dedented provides a clear delimiter -between two distinct sections of the code that otherwise share the same -indentation level (like the arguments list and the docstring in the -example above). - -Unnecessary trailing commas are removed if an expression fits in one -line. This makes it 1% more likely that your line won't exceed the -allotted line length limit. - -*Black* avoids spurious vertical whitespace. This is in the spirit of -PEP 8 which says that in-function vertical whitespace should only be -used sparingly. One exception is control flow statements: *Black* will -always emit an extra empty line after ``return``, ``raise``, ``break``, -``continue``, and ``yield``. This is to make changes in control flow -more prominent to readers of your code. - -That's it. The rest of the whitespace formatting rules follow PEP 8 and -are designed to keep `pycodestyle` quiet. - - -### Line length - -You probably noticed the peculiar default line length. *Black* defaults -to 88 characters per line, which happens to be 10% over 80. This number -was found to produce significantly shorter files than sticking with 80 -(the most popular), or even 79 (used by the standard library). In -general, [90-ish seems like the wise choice](https://youtu.be/wf-BqAjZb8M?t=260). - -If you're paid by the line of code you write, you can pass -`--line-length` with a lower number. *Black* will try to respect that. -However, sometimes it won't be able to without breaking other rules. In -those rare cases, auto-formatted code will exceed your allotted limit. - -You can also increase it, but remember that people with sight disabilities -find it harder to work with line lengths exceeding 100 characters. -It also adversely affects side-by-side diff review on typical screen -resolutions. Long lines also make it harder to present code neatly -in documentation or talk slides. - -If you're using Flake8, you can bump `max-line-length` to 88 and forget -about it. Alternatively, use [Bugbear](https://github.com/PyCQA/flake8-bugbear)'s -B950 warning instead of E501 and keep the max line length at 80 which -you are probably already using. You'd do it like this: -```ini -[flake8] -max-line-length = 80 -... -select = C,E,F,W,B,B950 -ignore = E501 -``` +- [Usage and Configuration](https://black.readthedocs.io/en/stable/usage_and_configuration/index.html) -You'll find *Black*'s own .flake8 config file is configured like this. -If you're curious about the reasoning behind B950, Bugbear's documentation -explains it. The tl;dr is "it's like highway speed limits, we won't -bother you if you overdo it by a few km/h". +_Black_ is already [successfully used](https://github.com/psf/black#used-by) by many +projects, small and big. _Black_ has a comprehensive test suite, with efficient parallel +tests, and our own auto formatting and parallel Continuous Integration runner. Now that +we have become stable, you should not expect large formatting to changes in the future. +Stylistic changes will mostly be responses to bug reports and support for new Python +syntax. For more information please refer to the +[The Black Code Style](docs/the_black_code_style/index.rst). +Also, as a safety measure which slows down processing, _Black_ will check that the +reformatted code still produces a valid AST that is effectively equivalent to the +original (see the +[Pragmatism](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#ast-before-and-after-formatting) +section for details). If you're feeling confident, use `--fast`. -### Editor integration +## The _Black_ code style -There is currently no integration with any text editors. Vim and -Atom/Nuclide integration is planned by the author, others will require -external contributions. +_Black_ is a PEP 8 compliant opinionated formatter. _Black_ reformats entire files in +place. Style configuration options are deliberately limited and rarely added. It doesn't +take previous formatting into account (see [Pragmatism](#pragmatism) for exceptions). -Patches welcome! ✨ 🍰 ✨ +Our documentation covers the current _Black_ code style, but planned changes to it are +also documented. They're both worth taking a look: +- [The _Black_ Code Style: Current style](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html) +- [The _Black_ Code Style: Future style](https://black.readthedocs.io/en/stable/the_black_code_style/future_style.html) -## Testimonials +Please refer to this document before submitting an issue. What seems like a bug might be +intended behaviour. -**Dusty Phillips**, [writer](https://smile.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=dusty+phillips): +### Pragmatism -> Black is opinionated so you don't have to be. +Early versions of _Black_ used to be absolutist in some respects. They took after its +initial author. This was fine at the time as it made the implementation simpler and +there were not many users anyway. Not many edge cases were reported. As a mature tool, +_Black_ does make some exceptions to rules it otherwise holds. -**Hynek Schlawack**, [creator of `attrs`](http://www.attrs.org/), core -developer of Twisted and CPython: +- [The _Black_ code style: Pragmatism](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#pragmatism) -> An auto-formatter that doesn't suck is all I want for Xmas! - -**Carl Meyer**, [Django](https://www.djangoproject.com/) core developer: +Please refer to this document before submitting an issue just like with the document +above. What seems like a bug might be intended behaviour. -> At least the name is good. +## Configuration -**Kenneth Reitz**, creator of [`requests`](http://python-requests.org/) -and [`pipenv`](https://docs.pipenv.org/): +_Black_ is able to read project-specific default values for its command line options +from a `pyproject.toml` file. This is especially useful for specifying custom +`--include` and `--exclude`/`--force-exclude`/`--extend-exclude` patterns for your +project. -> This vastly improves the formatting of our code. Thanks a ton! +You can find more details in our documentation: +- [The basics: Configuration via a file](https://black.readthedocs.io/en/stable/usage_and_configuration/the_basics.html#configuration-via-a-file) -## Tests +And if you're looking for more general configuration documentation: -Just run: +- [Usage and Configuration](https://black.readthedocs.io/en/stable/usage_and_configuration/index.html) -``` -python setup.py test -``` +**Pro-tip**: If you're asking yourself "Do I need to configure anything?" the answer is +"No". _Black_ is all about sensible defaults. Applying those defaults will have your +code in compliance with many other _Black_ formatted projects. -## This tool requires Python 3.6.0+ to run +## Used by -But you can reformat Python 2 code with it, too. *Black* is able to parse -all of the new syntax supported on Python 3.6 but also *effectively all* -the Python 2 syntax at the same time, as long as you're not using print -statements. +The following notable open-source projects trust _Black_ with enforcing a consistent +code style: pytest, tox, Pyramid, Django Channels, Hypothesis, attrs, SQLAlchemy, +Poetry, PyPA applications (Warehouse, Bandersnatch, Pipenv, virtualenv), pandas, Pillow, +Twisted, LocalStack, every Datadog Agent Integration, Home Assistant, Zulip, Kedro, +OpenOA, FLORIS, ORBIT, WOMBAT, and many more. -By making the code exclusively Python 3.6+, I'm able to focus on the -quality of the formatting and re-use all the nice features of the new -releases (check out [pathlib](https://docs.python.org/3/library/pathlib.html) or -f-strings) instead of wasting cycles on Unicode compatibility, and so on. +The following organizations use _Black_: Facebook, Dropbox, KeepTruckin, Mozilla, Quora, +Duolingo, QuantumBlack, Tesla. +Are we missing anyone? Let us know. -## License - -MIT +## Testimonials +**Mike Bayer**, [author of `SQLAlchemy`](https://www.sqlalchemy.org/): -## Contributing +> I can't think of any single tool in my entire programming career that has given me a +> bigger productivity increase by its introduction. I can now do refactorings in about +> 1% of the keystrokes that it would have taken me previously when we had no way for +> code to format itself. -In terms of inspiration, *Black* is about as configurable as *gofmt* and -*rustfmt* are. This is deliberate. +**Dusty Phillips**, +[writer](https://smile.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=dusty+phillips): -Bug reports and fixes are always welcome! However, before you suggest a -new feature or configuration knob, ask yourself why you want it. If it -enables better integration with some workflow, fixes an inconsistency, -speeds things up, and so on - go for it! On the other hand, if your -answer is "because I don't like a particular formatting" then you're not -ready to embrace *Black* yet. Such changes are unlikely to get accepted. -You can still try but prepare to be disappointed. +> _Black_ is opinionated so you don't have to be. -More details can be found in [CONTRIBUTING](CONTRIBUTING.md). +**Hynek Schlawack**, [creator of `attrs`](https://www.attrs.org/), core developer of +Twisted and CPython: +> An auto-formatter that doesn't suck is all I want for Xmas! -## Change Log +**Carl Meyer**, [Django](https://www.djangoproject.com/) core developer: -### 18.3a2 +> At least the name is good. -* changed positioning of binary operators to occur at beginning of lines - instead of at the end, following [a recent change to PEP8](https://github.com/python/peps/commit/c59c4376ad233a62ca4b3a6060c81368bd21e85b) - (#21) +**Kenneth Reitz**, creator of [`requests`](http://python-requests.org/) and +[`pipenv`](https://readthedocs.org/projects/pipenv/): -* ignore empty bracket pairs while splitting. This avoids very weirdly - looking formattings (#34, #35) +> This vastly improves the formatting of our code. Thanks a ton! -* remove a trailing comma if there is a single argument to a call +## Show your style -* if top level functions were separated by a comment, don't put four - empty lines after the upper function +Use the badge in your project's README.md: -* fixed unstable formatting of newlines with imports +```md +[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black) +``` -* fixed unintentional folding of post scriptum standalone comments - into last statement if it was a simple statement (#18, #28) +Using the badge in README.rst: -* fixed missing space in numpy-style array indexing (#33) +``` +.. image:: https://img.shields.io/badge/code%20style-black-000000.svg + :target: https://github.com/psf/black +``` -* fixed spurious space after star-based unary expressions (#31) +Looks like this: +[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black) +## License -### 18.3a1 +MIT -* added `--check` +## Contributing -* only put trailing commas in function signatures and calls if it's - safe to do so. If the file is Python 3.6+ it's always safe, otherwise - only safe if there are no `*args` or `**kwargs` used in the signature - or call. (#8) +Welcome! Happy to see you willing to make the project better. You can get started by +reading this: -* fixed invalid spacing of dots in relative imports (#6, #13) +- [Contributing: The basics](https://black.readthedocs.io/en/latest/contributing/the_basics.html) -* fixed invalid splitting after comma on unpacked variables in for-loops - (#23) +You can also take a look at the rest of the contributing docs or talk with the +developers: -* fixed spurious space in parenthesized set expressions (#7) +- [Contributing documentation](https://black.readthedocs.io/en/latest/contributing/index.html) +- [Chat on Discord](https://discord.gg/RtVdv86PrH) -* fixed spurious space after opening parentheses and in default - arguments (#14, #17) +## Change log -* fixed spurious space after unary operators when the operand was - a complex expression (#15) +The log has become rather long. It moved to its own file. +See [CHANGES](https://black.readthedocs.io/en/latest/change_log.html). -### 18.3a0 +## Authors -* first published version, Happy 🍰 Day 2018! +The author list is quite long nowadays, so it lives in its own file. -* alpha quality +See [AUTHORS.md](./AUTHORS.md) -* date-versioned (see: https://calver.org/) +## Code of Conduct +Everyone participating in the _Black_ project, and in particular in the issue tracker, +pull requests, and social media activity, is expected to treat other people with respect +and more generally to follow the guidelines articulated in the +[Python Community Code of Conduct](https://www.python.org/psf/codeofconduct/). -## Authors +At the same time, humor is encouraged. In fact, basic familiarity with Monty Python's +Flying Circus is expected. We are not savages. -Glued together by [Łukasz Langa](mailto:lukasz@langa.pl). +And if you _really_ need to slap somebody, do it with a fish while dancing.