*Black* makes code review faster by producing the smallest diffs
possible.
+---
+
+*Contents:* **[Installation and usage](#installation-and-usage)** |
+**[The *Black* code style](#the-black-code-style)** |
+**[Editor integration](#editor-integration)** |
+**[Version control integration](#version-control-integration)** |
+**[Ignoring unmodified files](#ignoring-unmodified-files)** |
+**[Testimonials](#testimonials)** |
+**[Show your style](#show-your-style)** |
+**[License](#license)** |
+**[Contributing](#contributing-to-black)** |
+**[Change Log](#change-log)** |
+**[Authors](#authors)**
+
+---
## Installation and usage
Options:
-l, --line-length INTEGER Where to wrap around. [default: 88]
+ --py36 Allow using Python 3.6-only syntax on all input
+ files. This will put trailing commas in function
+ signatures and calls also after *args and
+ **kwargs. [default: per-file auto-detection]
+ --pyi Format all input files like typing stubs
+ regardless of file extension (useful when piping
+ source on standard input).
+ -S, --skip-string-normalization
+ Don't normalize string quotes or prefixes.
--check Don't write the files back, just return the
status. Return code 0 means nothing would
change. Return code 1 means some files would be
for each file on stdout.
--fast / --safe If --fast given, skip temporary sanity checks.
[default: --safe]
+ --include TEXT A regular expression that matches files and
+ directories that should be included on
+ recursive searches. On Windows, use forward
+ slashes for directories. [default: \.pyi?$]
+ --exclude TEXT A regular expression that matches files and
+ directories that should be excluded on
+ recursive searches. On Windows, use forward
+ slashes for directories. [default:
+ build/|buck-out/|dist/|_build/|\.git/|\.hg/|
+ \.mypy_cache/|\.tox/|\.venv/]
-q, --quiet Don't emit non-error messages to stderr. Errors
are still emitted, silence those with
2>/dev/null.
imports cannot fit in the allotted length, it's always split into one
element per line. This minimizes diffs as well as enables readers of
code to find which commit introduced a particular entry. This also
-makes *Black* compatible with [isort](https://pypi.org/p/isort/). Use
-`multi_line_output=3`, `include_trailing_comma=True`,
-`force_grid_wrap=0`, and `line_length=88` in your isort config.
+makes *Black* compatible with [isort](https://pypi.org/p/isort/) with
+the following configuration.
+<details>
+<summary>A compatible `.isort.cfg`</summary>
+
+```
+[settings]
+multi_line_output=3
+include_trailing_comma=True
+force_grid_wrap=0
+combine_as_imports=True
+line_length=88
+```
+
+The equivalent command line is:
+```
+$ isort --multi-line=3 --trailing-comma --force-grid-wrap=0 --combine-as --line-width=88 [ file.py ]
+```
+</details>
### Line length
It will also insert proper spacing before and after function definitions.
It's one line before and after inner functions and two lines before and
-after module-level functions. *Black* will not put empty lines between
-function/class definitions and standalone comments that immediately precede
-the given function/class.
+after module-level functions and classes. *Black* will not put empty
+lines between function/class definitions and standalone comments that
+immediately precede the given function/class.
+
+*Black* will enforce single empty lines between a class-level docstring
+and the first following field or method. This conforms to
+[PEP 257](https://www.python.org/dev/peps/pep-0257/#multi-line-docstrings).
+
+*Black* won't insert empty lines after function docstrings unless that
+empty line is required due to an inner function starting immediately
+after.
### Trailing commas
key. My recommendation here is to keep using whatever is faster to type
and let *Black* handle the transformation.
+If you are adopting *Black* in a large project with pre-existing string
+conventions (like the popular ["single quotes for data, double quotes for
+human-readable strings"](https://stackoverflow.com/a/56190)), you can
+pass `--skip-string-normalization` on the command line. This is meant as
+an adoption helper, avoid using this for new projects.
+
### Line breaks & binary operators
Some popular APIs, like ORMs, use call chaining. This API style is known
as a [fluent interface](https://en.wikipedia.org/wiki/Fluent_interface).
-*Black* formats those treating dots that follow a call or an indexing
+*Black* formats those by treating dots that follow a call or an indexing
operation like a very low priority delimiter. It's easier to show the
behavior than to explain it. Look at the example:
```py3
- Arguments: $FilePath$
5. Format the currently opened file by selecting `Tools -> External Tools -> black`.
- - Alternatively, you can set a keyboard shortcut by navigating to `Preferences -> Keymap`.
+ - Alternatively, you can set a keyboard shortcut by navigating to `Preferences -> Keymap -> External Tools -> External Tools - Black`.
### Vim
create a virtualenv manually and point `g:black_virtualenv` to it.
The plugin will use it.
+To run *Black* on save, add the following line to `.vimrc` or `init.vim`:
+
+```
+autocmd BufWritePost *.py execute ':Black'
+```
+
**How to get Vim with Python 3.6?**
On Ubuntu 17.10 Vim comes with Python 3.6 by default.
On macOS with Homebrew run: `brew install vim --with-python3`.
hooks:
- id: black
args: [--line-length=88, --safe]
- python_version: python3.6
+ language_version: python3.6
```
Then run `pre-commit install` and you're ready to go.
`args` in the above config is optional but shows you how you can change
the line length if you really need to. If you're already using Python
-3.7, switch the `python_version` accordingly. Finally, `stable` is a tag
+3.7, switch the `language_version` accordingly. Finally, `stable` is a tag
that is pinned to the latest release on PyPI. If you'd rather run on
master, this is also an option.
-## Ignoring non-modified files
+## Ignoring unmodified files
-*Black* remembers files it already formatted, unless the `--diff` flag is used or
+*Black* remembers files it has already formatted, unless the `--diff` flag is used or
code is passed via standard input. This information is stored per-user. The exact
location of the file depends on the black version and the system on which black
is run. The file is non-portable. The standard location on common operating systems
## Change Log
+### 18.6b0
+
+* added `--include` and `--exclude` (#270)
+
+* added `--skip-string-normalization` (#118)
+
+* fixed stdin handling not working correctly if an old version of Click was
+ used (#276)
+
+
+### 18.5b1
+
+* added `--pyi` (#249)
+
+* added `--py36` (#249)
+
+* Python grammar pickle caches are stored with the formatting caches, making
+ *Black* work in environments where site-packages is not user-writable (#192)
+
+* *Black* now enforces a PEP 257 empty line after a class-level docstring
+ (and/or fields) and the first method
+
+* fixed invalid code produced when standalone comments were present in a trailer
+ that was omitted from line splitting on a large expression (#237)
+
+* fixed optional parentheses being removed within `# fmt: off` sections (#224)
+
+* fixed invalid code produced when stars in very long imports were incorrectly
+ wrapped in optional parentheses (#234)
+
+* fixed unstable formatting when inline comments were moved around in
+ a trailer that was omitted from line splitting on a large expression
+ (#238)
+
+* fixed extra empty line between a class declaration and the first
+ method if no class docstring or fields are present (#219)
+
+* fixed extra empty line between a function signature and an inner
+ function or inner class (#196)
+
+
### 18.5b0
* call chains are now formatted according to the
* [Ivan Katanić](mailto:ivan.katanic@gmail.com)
* [Jelle Zijlstra](mailto:jelle.zijlstra@gmail.com)
* [Jonas Obrist](mailto:ojiidotch@gmail.com)
+* [Luka Sterbic](mailto:luka.sterbic@gmail.com)
* [Miguel Gaiowski](mailto:miggaiowski@gmail.com)
* [Osaetin Daniel](mailto:osaetindaniel@gmail.com)
+* [Stavros Korokithakis](mailto:hi@stavros.io)
* [Sunil Kapil](mailto:snlkapil@gmail.com)
* [Vishwas B Sharma](mailto:sharma.vishwas88@gmail.com)
+
+---
+
+*Contents:*
+**[Installation and Usage](#installation-and-usage)** |
+**[The *Black* code style](#the-black-code-style)** |
+**[Editor integration](#editor-integration)** |
+**[Version control integration](#version-control-integration)** |
+**[Ignoring unmodified files](#ignoring-unmodified-files)** |
+**[Testimonials](#testimonials)** |
+**[Show your style](#show-your-style)** |
+**[License](#license)** |
+**[Contributing](#contributing-to-black)** |
+**[Change Log](#change-log)** |
+**[Authors](#authors)**