README.md

   1 ![Black Logo](https://raw.githubusercontent.com/psf/black/main/docs/_static/logo2-readme.png)
   2
   3 <h2 align="center">The Uncompromising Code Formatter</h2>
   4
   5 <p align="center">
   6 <a href="https://github.com/psf/black/actions"><img alt="Actions Status" src="https://github.com/psf/black/workflows/Test/badge.svg"></a>
   7 <a href="https://github.com/psf/black/actions"><img alt="Actions Status" src="https://github.com/psf/black/workflows/Primer/badge.svg"></a>
   8 <a href="https://black.readthedocs.io/en/stable/?badge=stable"><img alt="Documentation Status" src="https://readthedocs.org/projects/black/badge/?version=stable"></a>
   9 <a href="https://coveralls.io/github/psf/black?branch=main"><img alt="Coverage Status" src="https://coveralls.io/repos/github/psf/black/badge.svg?branch=main"></a>
  10 <a href="https://github.com/psf/black/blob/main/LICENSE"><img alt="License: MIT" src="https://black.readthedocs.io/en/stable/_static/license.svg"></a>
  11 <a href="https://pypi.org/project/black/"><img alt="PyPI" src="https://img.shields.io/pypi/v/black"></a>
  12 <a href="https://pepy.tech/project/black"><img alt="Downloads" src="https://pepy.tech/badge/black"></a>
  13 <a href="https://anaconda.org/conda-forge/black/"><img alt="conda-forge" src="https://img.shields.io/conda/dn/conda-forge/black.svg?label=conda-forge"></a>
  14 <a href="https://github.com/psf/black"><img alt="Code style: black" src="https://img.shields.io/badge/code%20style-black-000000.svg"></a>
  15 </p>
  16
  17 > “Any color you like.”
  18
  19 _Black_ is the uncompromising Python code formatter. By using it, you agree to cede
  20 control over minutiae of hand-formatting. In return, _Black_ gives you speed,
  21 determinism, and freedom from `pycodestyle` nagging about formatting. You will save time
  22 and mental energy for more important matters.
  23
  24 Blackened code looks the same regardless of the project you're reading. Formatting
  25 becomes transparent after a while and you can focus on the content instead.
  26
  27 _Black_ makes code review faster by producing the smallest diffs possible.
  28
  29 Try it out now using the [Black Playground](https://black.vercel.app). Watch the
  30 [PyCon 2019 talk](https://youtu.be/esZLCuWs_2Y) to learn more.
  31
  32 ---
  33
  34 **[Read the documentation on ReadTheDocs!](https://black.readthedocs.io/en/stable)**
  35
  36 ---
  37
  38 ## Installation and usage
  39
  40 ### Installation
  41
  42 _Black_ can be installed by running `pip install black`. It requires Python 3.6.2+ to
  43 run. If you want to format Python 2 code as well, install with
  44 `pip install black[python2]`. If you want to format Jupyter Notebooks, install with
  45 `pip install black[jupyter]`.
  46
  47 If you can't wait for the latest _hotness_ and want to install from GitHub, use:
  48
  49 `pip install git+git://github.com/psf/black`
  50
  51 ### Usage
  52
  53 To get started right away with sensible defaults:
  54
  55 ```sh
  56 black {source_file_or_directory}
  57 ```
  58
  59 You can run _Black_ as a package if running it as a script doesn't work:
  60
  61 ```sh
  62 python -m black {source_file_or_directory}
  63 ```
  64
  65 Further information can be found in our docs:
  66
  67 - [Usage and Configuration](https://black.readthedocs.io/en/stable/usage_and_configuration/index.html)
  68
  69 ### NOTE: This is a beta product
  70
  71 _Black_ is already [successfully used](https://github.com/psf/black#used-by) by many
  72 projects, small and big. Black has a comprehensive test suite, with efficient parallel
  73 tests, and our own auto formatting and parallel Continuous Integration runner. However,
  74 _Black_ is still beta. Things will probably be wonky for a while. This is made explicit
  75 by the "Beta" trove classifier, as well as by the "b" in the version number. What this
  76 means for you is that **until the formatter becomes stable, you should expect some
  77 formatting to change in the future**. That being said, no drastic stylistic changes are
  78 planned, mostly responses to bug reports.
  79
  80 Also, as a safety measure which slows down processing, _Black_ will check that the
  81 reformatted code still produces a valid AST that is effectively equivalent to the
  82 original (see the
  83 [Pragmatism](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#ast-before-and-after-formatting)
  84 section for details). If you're feeling confident, use `--fast`.
  85
  86 ## The _Black_ code style
  87
  88 _Black_ is a PEP 8 compliant opinionated formatter. _Black_ reformats entire files in
  89 place. Style configuration options are deliberately limited and rarely added. It doesn't
  90 take previous formatting into account (see [Pragmatism](#pragmatism) for exceptions).
  91
  92 Our documentation covers the current _Black_ code style, but planned changes to it are
  93 also documented. They're both worth taking a look:
  94
  95 - [The _Black_ Code Style: Current style](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html)
  96 - [The _Black_ Code Style: Future style](https://black.readthedocs.io/en/stable/the_black_code_style/future_style.html)
  97
  98 Please refer to this document before submitting an issue. What seems like a bug might be
  99 intended behaviour.
 100
 101 ### Pragmatism
 102
 103 Early versions of _Black_ used to be absolutist in some respects. They took after its
 104 initial author. This was fine at the time as it made the implementation simpler and
 105 there were not many users anyway. Not many edge cases were reported. As a mature tool,
 106 _Black_ does make some exceptions to rules it otherwise holds.
 107
 108 - [The _Black_ code style: Pragmatism](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#pragmatism)
 109
 110 Please refer to this document before submitting an issue just like with the document
 111 above. What seems like a bug might be intended behaviour.
 112
 113 ## Configuration
 114
 115 _Black_ is able to read project-specific default values for its command line options
 116 from a `pyproject.toml` file. This is especially useful for specifying custom
 117 `--include` and `--exclude`/`--force-exclude`/`--extend-exclude` patterns for your
 118 project.
 119
 120 You can find more details in our documentation:
 121
 122 - [The basics: Configuration via a file](https://black.readthedocs.io/en/stable/usage_and_configuration/the_basics.html#configuration-via-a-file)
 123
 124 And if you're looking for more general configuration documentation:
 125
 126 - [Usage and Configuration](https://black.readthedocs.io/en/stable/usage_and_configuration/index.html)
 127
 128 **Pro-tip**: If you're asking yourself "Do I need to configure anything?" the answer is
 129 "No". _Black_ is all about sensible defaults. Applying those defaults will have your
 130 code in compliance with many other _Black_ formatted projects.
 131
 132 ## Used by
 133
 134 The following notable open-source projects trust _Black_ with enforcing a consistent
 135 code style: pytest, tox, Pyramid, Django Channels, Hypothesis, attrs, SQLAlchemy,
 136 Poetry, PyPA applications (Warehouse, Bandersnatch, Pipenv, virtualenv), pandas, Pillow,
 137 Twisted, LocalStack, every Datadog Agent Integration, Home Assistant, Zulip, Kedro, and
 138 many more.
 139
 140 The following organizations use _Black_: Facebook, Dropbox, Mozilla, Quora, Duolingo,
 141 QuantumBlack.
 142
 143 Are we missing anyone? Let us know.
 144
 145 ## Testimonials
 146
 147 **Mike Bayer**, [author of `SQLAlchemy`](https://www.sqlalchemy.org/):
 148
 149 > I can't think of any single tool in my entire programming career that has given me a
 150 > bigger productivity increase by its introduction. I can now do refactorings in about
 151 > 1% of the keystrokes that it would have taken me previously when we had no way for
 152 > code to format itself.
 153
 154 **Dusty Phillips**,
 155 [writer](https://smile.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=dusty+phillips):
 156
 157 > _Black_ is opinionated so you don't have to be.
 158
 159 **Hynek Schlawack**, [creator of `attrs`](https://www.attrs.org/), core developer of
 160 Twisted and CPython:
 161
 162 > An auto-formatter that doesn't suck is all I want for Xmas!
 163
 164 **Carl Meyer**, [Django](https://www.djangoproject.com/) core developer:
 165
 166 > At least the name is good.
 167
 168 **Kenneth Reitz**, creator of [`requests`](http://python-requests.org/) and
 169 [`pipenv`](https://readthedocs.org/projects/pipenv/):
 170
 171 > This vastly improves the formatting of our code. Thanks a ton!
 172
 173 ## Show your style
 174
 175 Use the badge in your project's README.md:
 176
 177 ```md
 178 [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
 179 ```
 180
 181 Using the badge in README.rst:
 182
 183 ```
 184 .. image:: https://img.shields.io/badge/code%20style-black-000000.svg
 185     :target: https://github.com/psf/black
 186 ```
 187
 188 Looks like this:
 189 [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
 190
 191 ## License
 192
 193 MIT
 194
 195 ## Contributing
 196
 197 Welcome! Happy to see you willing to make the project better. You can get started by
 198 reading this:
 199
 200 - [Contributing: The basics](https://black.readthedocs.io/en/latest/contributing/the_basics.html)
 201
 202 You can also take a look at the rest of the contributing docs or talk with the
 203 developers:
 204
 205 - [Contributing documentation](https://black.readthedocs.io/en/latest/contributing/index.html)
 206 - [Chat on Discord](https://discord.gg/RtVdv86PrH)
 207
 208 ## Change log
 209
 210 The log has become rather long. It moved to its own file.
 211
 212 See [CHANGES](https://black.readthedocs.io/en/latest/change_log.html).
 213
 214 ## Authors
 215
 216 The author list is quite long nowadays, so it lives in its own file.
 217
 218 See [AUTHORS.md](./AUTHORS.md)
 219
 220 ## Code of Conduct
 221
 222 Everyone participating in the _Black_ project, and in particular in the issue tracker,
 223 pull requests, and social media activity, is expected to treat other people with respect
 224 and more generally to follow the guidelines articulated in the
 225 [Python Community Code of Conduct](https://www.python.org/psf/codeofconduct/).
 226
 227 At the same time, humor is encouraged. In fact, basic familiarity with Monty Python's
 228 Flying Circus is expected. We are not savages.
 229
 230 And if you _really_ need to slap somebody, do it with a fish while dancing.