]> git.madduck.net Git - etc/vim.git/blob - docs/pyproject_toml.md

madduck's git repository

Every one of the projects in this repository is available at the canonical URL git://git.madduck.net/madduck/pub/<projectpath> — see each project's metadata for the exact URL.

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.

SSH access, as well as push access can be individually arranged.

If you use my repositories frequently, consider adding the following snippet to ~/.gitconfig and using the third clone URL listed for each project:

[url "git://git.madduck.net/madduck/"]
  insteadOf = madduck:

Simplify black code by using generator expressions
[etc/vim.git] / docs / pyproject_toml.md
1 [//]: # "NOTE: THIS FILE WAS AUTOGENERATED FROM README.md"
2
3 # pyproject.toml
4
5 _Black_ is able to read project-specific default values for its command line options
6 from a `pyproject.toml` file. This is especially useful for specifying custom
7 `--include` and `--exclude` patterns for your project.
8
9 **Pro-tip**: If you're asking yourself "Do I need to configure anything?" the answer is
10 "No". _Black_ is all about sensible defaults.
11
12 ## What on Earth is a `pyproject.toml` file?
13
14 [PEP 518](https://www.python.org/dev/peps/pep-0518/) defines `pyproject.toml` as a
15 configuration file to store build system requirements for Python projects. With the help
16 of tools like [Poetry](https://python-poetry.org/) or
17 [Flit](https://flit.readthedocs.io/en/latest/) it can fully replace the need for
18 `setup.py` and `setup.cfg` files.
19
20 ## Where _Black_ looks for the file
21
22 By default _Black_ looks for `pyproject.toml` starting from the common base directory of
23 all files and directories passed on the command line. If it's not there, it looks in
24 parent directories. It stops looking when it finds the file, or a `.git` directory, or a
25 `.hg` directory, or the root of the file system, whichever comes first.
26
27 If you're formatting standard input, _Black_ will look for configuration starting from
28 the current working directory.
29
30 You can also explicitly specify the path to a particular file that you want with
31 `--config`. In this situation _Black_ will not look for any other file.
32
33 If you're running with `--verbose`, you will see a blue message if a file was found and
34 used.
35
36 Please note `blackd` will not use `pyproject.toml` configuration.
37
38 ## Configuration format
39
40 As the file extension suggests, `pyproject.toml` is a
41 [TOML](https://github.com/toml-lang/toml) file. It contains separate sections for
42 different tools. _Black_ is using the `[tool.black]` section. The option keys are the
43 same as long names of options on the command line.
44
45 Note that you have to use single-quoted strings in TOML for regular expressions. It's
46 the equivalent of r-strings in Python. Multiline strings are treated as verbose regular
47 expressions by Black. Use `[ ]` to denote a significant space character.
48
49 <details>
50 <summary>Example <code>pyproject.toml</code></summary>
51
52 ```toml
53 [tool.black]
54 line-length = 88
55 target-version = ['py37']
56 include = '\.pyi?$'
57 exclude = '''
58
59 (
60   /(
61       \.eggs         # exclude a few common directories in the
62     | \.git          # root of the project
63     | \.hg
64     | \.mypy_cache
65     | \.tox
66     | \.venv
67     | _build
68     | buck-out
69     | build
70     | dist
71   )/
72   | foo.py           # also separately exclude a file named foo.py in
73                      # the root of the project
74 )
75 '''
76 ```
77
78 </details>
79
80 ## Lookup hierarchy
81
82 Command-line options have defaults that you can see in `--help`. A `pyproject.toml` can
83 override those defaults. Finally, options provided by the user on the command line
84 override both.
85
86 _Black_ will only ever use one `pyproject.toml` file during an entire run. It doesn't
87 look for multiple files, and doesn't compose configuration from different levels of the
88 file hierarchy.