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