X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/26b92e66aca6124ba8761f690ec7ee18757411b7..4809e365d43ff5f837f9dacbc1f3d04975fe35e8:/README.md diff --git a/README.md b/README.md index 3f82dbd..b6218cf 100644 --- a/README.md +++ b/README.md @@ -3,10 +3,11 @@

Build Status -Documentation Status +Documentation Status Coverage Status -License: MIT -PyPI +License: MIT +PyPI +Downloads Code style: black

@@ -26,16 +27,19 @@ content instead. *Black* makes code review faster by producing the smallest diffs possible. +Try it out now using the [Black Playground](https://black.now.sh). + --- *Contents:* **[Installation and usage](#installation-and-usage)** | -**[The *Black* code style](#the-black-code-style)** | +**[Code style](#the-black-code-style)** | +**[pyproject.toml](#pyprojecttoml)** | **[Editor integration](#editor-integration)** | +**[blackd](#blackd)** | **[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)** @@ -60,7 +64,7 @@ black {source_file_or_directory} ### Command line options -Black doesn't provide many options. You can list them by running +*Black* doesn't provide many options. You can list them by running `black --help`: ```text @@ -77,6 +81,8 @@ Options: source on standard input). -S, --skip-string-normalization Don't normalize string quotes or prefixes. + -N, --skip-numeric-underscore-normalization + Don't normalize underscores in numeric literals. --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 @@ -95,7 +101,7 @@ Options: recursive searches. On Windows, use forward slashes for directories. [default: build/|buck-out/|dist/|_build/|\.git/|\.hg/| - \.mypy_cache/|\.tox/|\.venv/] + \.mypy_cache/|\.nox/|\.tox/|\.venv/] -q, --quiet Don't emit non-error messages to stderr. Errors are still emitted, silence those with 2>/dev/null. @@ -103,6 +109,7 @@ Options: that were not changed or were ignored due to --exclude=. --version Show the version and exit. + --config PATH Read configuration from PATH. --help Show this message and exit. ``` @@ -136,7 +143,8 @@ original. This slows it down. If you're feeling confident, use *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 +blocks that start with `# fmt: off` and end with `# fmt: on`. `# fmt: on/off` +have to be on the same level of indentation. It also recognizes [YAPF](https://github.com/google/yapf)'s block comments to the same effect, as a courtesy for straddling code. @@ -230,13 +238,13 @@ the following configuration. multi_line_output=3 include_trailing_comma=True force_grid_wrap=0 -combine_as_imports=True +use_parentheses=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 ] +$ isort --multi-line=3 --trailing-comma --force-grid-wrap=0 --use-parentheses --line-width=88 [ file.py ] ``` @@ -272,7 +280,8 @@ ignore = E501 ``` 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 +If you're curious about the reasoning behind B950, +[Bugbear's documentation](https://github.com/PyCQA/flake8-bugbear#opinionated-warnings) 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". @@ -350,8 +359,8 @@ string literals that ended up on the same line (see [#26](https://github.com/ambv/black/issues/26) for details). Why settle on double quotes? They anticipate apostrophes in English -text. They match the docstring standard described in PEP 257. An -empty string in double quotes (`""`) is impossible to confuse with +text. They match the docstring standard described in [PEP 257](https://www.python.org/dev/peps/pep-0257/#what-is-a-docstring). +An empty string in double quotes (`""`) is impossible to confuse with a one double-quote regardless of fonts and syntax highlighting used. On top of this, double quotes for strings are consistent with C which Python interacts a lot with. @@ -367,6 +376,19 @@ 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. +### Numeric literals + +*Black* standardizes most numeric literals to use lowercase letters for the +syntactic parts and uppercase letters for the digits themselves: `0xAB` +instead of `0XAB` and `1e10` instead of `1E10`. Python 2 long literals are +styled as `2L` instead of `2l` to avoid confusion between `l` and `1`. In +Python 3.6+, *Black* adds underscores to long numeric literals to aid +readability: `100000000` becomes `100_000_000`. + +For regions where numerals are grouped differently (like [India](https://en.wikipedia.org/wiki/Indian_numbering_system) +and [China](https://en.wikipedia.org/wiki/Chinese_numerals#Whole_numbers)), +the `-N` or `--skip-numeric-underscore-normalization` command line option +makes *Black* preserve underscores in numeric literals. ### Line breaks & binary operators @@ -487,6 +509,100 @@ a future version of the formatter: * use `float` instead of `Union[int, float]`. +## pyproject.toml + +*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` +patterns for your project. + +**Pro-tip**: If you're asking yourself "Do I need to configure anything?" +the answer is "No". *Black* is all about sensible defaults. + + +### What on Earth is a `pyproject.toml` file? + +[PEP 518](https://www.python.org/dev/peps/pep-0518/) defines +`pyproject.toml` as a configuration file to store build system +requirements for Python projects. With the help of tools +like [Poetry](https://poetry.eustace.io/) or +[Flit](https://flit.readthedocs.io/en/latest/) it can fully replace the +need for `setup.py` and `setup.cfg` files. + + +### Where *Black* looks for the file + +By default *Black* looks for `pyproject.toml` starting from the common +base directory of all files and directories passed on the command line. +If it's not there, it looks in parent directories. It stops looking +when it finds the file, or a `.git` directory, or a `.hg` directory, +or the root of the file system, whichever comes first. + +If you're formatting standard input, *Black* will look for configuration +starting from the current working directory. + +You can also explicitly specify the path to a particular file that you +want with `--config`. In this situation *Black* will not look for any +other file. + +If you're running with `--verbose`, you will see a blue message if +a file was found and used. + +Please note `blackd` will not use `pyproject.toml` configuration. + + +### Configuration format + +As the file extension suggests, `pyproject.toml` is a [TOML](https://github.com/toml-lang/toml) file. It contains separate +sections for different tools. *Black* is using the `[tool.black]` +section. The option keys are the same as long names of options on +the command line. + +Note that you have to use single-quoted strings in TOML for regular +expressions. It's the equivalent of r-strings in Python. Multiline +strings are treated as verbose regular expressions by Black. Use `[ ]` +to denote a significant space character. + +
+Example `pyproject.toml` + +```toml +[tool.black] +line-length = 88 +py36 = true +include = '\.pyi?$' +exclude = ''' +/( + \.git + | \.hg + | \.mypy_cache + | \.tox + | \.venv + | _build + | buck-out + | build + | dist + + # The following are specific to Black, you probably don't want those. + | blib2to3 + | tests/data +)/ +''' +``` + +
+ +### Lookup hierarchy + +Command-line options have defaults that you can see in `--help`. +A `pyproject.toml` can override those defaults. Finally, options +provided by the user on the command line override both. + +*Black* will only ever use one `pyproject.toml` file during an entire +run. It doesn't look for multiple files, and doesn't compose +configuration from different levels of the file hierarchy. + + ## Editor integration ### Emacs @@ -524,17 +640,28 @@ $ where black - Name: Black - Description: Black is the uncompromising Python code formatter. - Program: - - Arguments: $FilePath$ + - 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 -> External Tools -> External Tools - Black`. +6. Optionally, run Black on every file save: + + 1. Make sure you have the [File Watcher](https://plugins.jetbrains.com/plugin/7177-file-watchers) plugin installed. + 2. Go to `Preferences -> Tools -> File Watchers` and click `+` to add a new watcher: + - Name: Black + - File type: Python + - Scope: Project Files + - Program: + - Arguments: `$FilePath$` + - Output paths to refresh: `$FilePathRelativeToProjectRoot$` + - Working directory: `$ProjectFileDir$` ### Vim Commands and shortcuts: -* `,=` or `:Black` to format the entire file (ranges not supported); +* `:Black` to format the entire file (ranges not supported); * `:BlackUpgrade` to upgrade *Black* inside the virtualenv; * `:BlackVersion` to get the current version of *Black* inside the virtualenv. @@ -542,12 +669,13 @@ Commands and shortcuts: Configuration: * `g:black_fast` (defaults to `0`) * `g:black_linelength` (defaults to `88`) +* `g:black_skip_string_normalization` (defaults to `0`) * `g:black_virtualenv` (defaults to `~/.vim/black`) To install with [vim-plug](https://github.com/junegunn/vim-plug): ``` -Plug 'ambv/black', +Plug 'ambv/black' ``` or with [Vundle](https://github.com/VundleVim/Vundle.vim): @@ -576,7 +704,7 @@ The plugin will use it. To run *Black* on save, add the following line to `.vimrc` or `init.vim`: ``` -autocmd BufWritePost *.py execute ':Black' +autocmd BufWritePre *.py execute ':Black' ``` **How to get Vim with Python 3.6?** @@ -589,7 +717,8 @@ to do this. ### Visual Studio Code -Use [joslarson.black-vscode](https://marketplace.visualstudio.com/items?itemName=joslarson.black-vscode). +Use the [Python extension](https://marketplace.visualstudio.com/items?itemName=ms-python.python) +([instructions](https://code.visualstudio.com/docs/python/editing#_formatting)). ### SublimeText 3 @@ -597,26 +726,110 @@ Use [joslarson.black-vscode](https://marketplace.visualstudio.com/items?itemName Use [sublack plugin](https://github.com/jgirardet/sublack). -### IPython Notebook Magic +### Jupyter Notebook Magic Use [blackcellmagic](https://github.com/csurfer/blackcellmagic). +### Python Language Server + +If your editor supports the [Language Server Protocol](https://langserver.org/) +(Atom, Sublime Text, Visual Studio Code and many more), you can use +the [Python Language Server](https://github.com/palantir/python-language-server) with the +[pyls-black](https://github.com/rupert/pyls-black) plugin. + + +### Atom/Nuclide + +Use [python-black](https://atom.io/packages/python-black). + + ### Other editors -Atom/Nuclide integration is planned by the author, others will -require external contributions. +Other editors will require external contributions. Patches welcome! ✨ 🍰 ✨ Any tool that can pipe code through *Black* using its stdio mode (just -[use `-` as the file name](http://www.tldp.org/LDP/abs/html/special-chars.html#DASHREF2)). +[use `-` as the file name](https://www.tldp.org/LDP/abs/html/special-chars.html#DASHREF2)). The formatted code will be returned on stdout (unless `--check` was passed). *Black* will still emit messages on stderr but that shouldn't affect your use case. This can be used for example with PyCharm's [File Watchers](https://www.jetbrains.com/help/pycharm/file-watchers.html). +## blackd + +`blackd` is a small HTTP server that exposes *Black*'s functionality over +a simple protocol. The main benefit of using it is to avoid paying the +cost of starting up a new *Black* process every time you want to blacken +a file. + +### Usage + +`blackd` is not packaged alongside *Black* by default because it has additional +dependencies. You will need to do `pip install black[d]` to install it. + +You can start the server on the default port, binding only to the local interface +by running `blackd`. You will see a single line mentioning the server's version, +and the host and port it's listening on. `blackd` will then print an access log +similar to most web servers on standard output, merged with any exception traces +caused by invalid formatting requests. + +`blackd` provides even less options than *Black*. You can see them by running +`blackd --help`: + +```text +Usage: blackd [OPTIONS] + +Options: + --bind-host TEXT Address to bind the server to. + --bind-port INTEGER Port to listen on + --version Show the version and exit. + -h, --help Show this message and exit. +``` + +### Protocol + +`blackd` only accepts `POST` requests at the `/` path. The body of the request +should contain the python source code to be formatted, encoded +according to the `charset` field in the `Content-Type` request header. If no +`charset` is specified, `blackd` assumes `UTF-8`. + +There are a few HTTP headers that control how the source is formatted. These +correspond to command line flags for *Black*. There is one exception to this: +`X-Protocol-Version` which if present, should have the value `1`, otherwise the +request is rejected with `HTTP 501` (Not Implemented). + +The headers controlling how code is formatted are: + + - `X-Line-Length`: corresponds to the `--line-length` command line flag. + - `X-Skip-String-Normalization`: corresponds to the `--skip-string-normalization` + command line flag. If present and its value is not the empty string, no string + normalization will be performed. + - `X-Skip-Numeric-Underscore-Normalization`: corresponds to the + `--skip-numeric-underscore-normalization` command line flag. + - `X-Fast-Or-Safe`: if set to `fast`, `blackd` will act as *Black* does when + passed the `--fast` command line flag. + - `X-Python-Variant`: if set to `pyi`, `blackd` will act as *Black* does when + passed the `--pyi` command line flag. Otherwise, its value must correspond to + a Python version. If this value represents at least Python 3.6, `blackd` will + act as *Black* does when passed the `--py36` command line flag. + +If any of these headers are set to invalid values, `blackd` returns a `HTTP 400` +error response, mentioning the name of the problematic header in the message body. + +Apart from the above, `blackd` can produce the following response codes: + + - `HTTP 204`: If the input is already well-formatted. The response body is + empty. + - `HTTP 200`: If formatting was needed on the input. The response body + contains the blackened Python code, and the `Content-Type` header is set + accordingly. + - `HTTP 400`: If the input contains a syntax error. Details of the error are + returned in the response body. + - `HTTP 500`: If there was any kind of error while trying to format the input. + The response body contains a textual representation of the error. ## Version control integration @@ -629,38 +842,43 @@ repos: rev: stable hooks: - id: black - args: [--line-length=88, --safe] 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 `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. +Avoid using `args` in the hook. Instead, store necessary configuration +in `pyproject.toml` so that editors and command-line usage of Black all +behave consistently for your project. See *Black*'s own `pyproject.toml` +for an example. + +If you're already using Python 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 unmodified files *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 +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 is: -* Windows: `C:\\Users\\AppData\Local\black\black\Cache\\cache..pickle` -* macOS: `/Users//Library/Caches/black//cache..pickle` -* Linux: `/home//.cache/black//cache..pickle` +* Windows: `C:\\Users\\AppData\Local\black\black\Cache\\cache...pickle` +* macOS: `/Users//Library/Caches/black//cache...pickle` +* Linux: `/home//.cache/black//cache...pickle` + +`file-mode` is an int flag that determines whether the file was formatted as 3.6+ only, +as .pyi, and whether string normalization was omitted. ## Testimonials **Dusty Phillips**, [writer](https://smile.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=dusty+phillips): -> Black is opinionated so you don't have to be. +> *Black* is opinionated so you don't have to be. -**Hynek Schlawack**, [creator of `attrs`](http://www.attrs.org/), core +**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! @@ -683,6 +901,12 @@ Use the badge in your project's README.md: [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/ambv/black) ``` +Using the badge in README.rst: +``` +.. image:: https://img.shields.io/badge/code%20style-black-000000.svg + :target: https://github.com/ambv/black +``` + Looks like this: [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/ambv/black) @@ -691,7 +915,7 @@ Looks like this: [![Code style: black](https://img.shields.io/badge/code%20style MIT -## Contributing to Black +## Contributing to *Black* In terms of inspiration, *Black* is about as configurable as *gofmt*. This is deliberate. @@ -709,6 +933,100 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md). ## Change Log +### 18.9b0 + +* numeric literals are now formatted by *Black* (#452, #461, #464, #469): + + * numeric literals are normalized to include `_` separators on Python 3.6+ code + + * added `--skip-numeric-underscore-normalization` to disable the above behavior and + leave numeric underscores as they were in the input + + * code with `_` in numeric literals is recognized as Python 3.6+ + + * most letters in numeric literals are lowercased (e.g., in `1e10`, `0x01`) + + * hexadecimal digits are always uppercased (e.g. `0xBADC0DE`) + +* added `blackd`, see [its documentation](#blackd) for more info (#349) + +* adjacent string literals are now correctly split into multiple lines (#463) + +* trailing comma is now added to single imports that don't fit on a line (#250) + +* cache is now populated when `--check` is successful for a file which speeds up + consecutive checks of properly formatted unmodified files (#448) + +* whitespace at the beginning of the file is now removed (#399) + +* fixed mangling [pweave](http://mpastell.com/pweave/) and + [Spyder IDE](https://pythonhosted.org/spyder/) special comments (#532) + +* fixed unstable formatting when unpacking big tuples (#267) + +* fixed parsing of `__future__` imports with renames (#389) + +* fixed scope of `# fmt: off` when directly preceding `yield` and other nodes (#385) + +* fixed formatting of lambda expressions with default arguments (#468) + +* fixed ``async for`` statements: *Black* no longer breaks them into separate + lines (#372) + +* note: the Vim plugin stopped registering ``,=`` as a default chord as it turned out + to be a bad idea (#415) + + +### 18.6b4 + +* hotfix: don't freeze when multiple comments directly precede `# fmt: off` (#371) + + +### 18.6b3 + +* typing stub files (`.pyi`) now have blank lines added after constants (#340) + +* `# fmt: off` and `# fmt: on` are now much more dependable: + + * they now work also within bracket pairs (#329) + + * they now correctly work across function/class boundaries (#335) + + * they now work when an indentation block starts with empty lines or misaligned + comments (#334) + +* made Click not fail on invalid environments; note that Click is right but the + likelihood we'll need to access non-ASCII file paths when dealing with Python source + code is low (#277) + +* fixed improper formatting of f-strings with quotes inside interpolated + expressions (#322) + +* fixed unnecessary slowdown when long list literals where found in a file + +* fixed unnecessary slowdown on AST nodes with very many siblings + +* fixed cannibalizing backslashes during string normalization + +* fixed a crash due to symbolic links pointing outside of the project directory (#338) + + +### 18.6b2 + +* added `--config` (#65) + +* added `-h` equivalent to `--help` (#316) + +* fixed improper unmodified file caching when `-S` was used + +* fixed extra space in string unpacking (#305) + +* fixed formatting of empty triple quoted strings (#313) + +* fixed unnecessary slowdown in comment placement calculation on lines without + comments + + ### 18.6b1 * hotfix: don't output human-facing information on stdout (#299) @@ -840,10 +1158,10 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md). * generalized star expression handling, including double stars; this fixes multiplication making expressions "unsafe" for trailing commas (#132) -* Black no longer enforces putting empty lines behind control flow statements +* *Black* no longer enforces putting empty lines behind control flow statements (#90) -* Black now splits imports like "Mode 3 + trailing comma" of isort (#127) +* *Black* now splits imports like "Mode 3 + trailing comma" of isort (#127) * fixed comment indentation when a standalone comment closes a block (#16, #32) @@ -896,16 +1214,16 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md). (#75) * fixed handling of standalone comments within nested bracketed - expressions; Black will no longer produce super long lines or put all + expressions; *Black* will no longer produce super long lines or put all standalone comments at the end of the expression (#22) * fixed 18.3a4 regression: don't crash and burn on empty lines with trailing whitespace (#80) * fixed 18.3a4 regression: `# yapf: disable` usage as trailing comment - would cause Black to not emit the rest of the file (#95) + would cause *Black* to not emit the rest of the file (#95) -* when CTRL+C is pressed while formatting many files, Black no longer +* when CTRL+C is pressed while formatting many files, *Black* no longer freaks out with a flurry of asyncio-related exceptions * only allow up to two empty lines on module level and only single empty @@ -952,7 +1270,7 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md). ### 18.3a2 * 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) + instead of at the end, following [a recent change to PEP 8](https://github.com/python/peps/commit/c59c4376ad233a62ca4b3a6060c81368bd21e85b) (#21) * ignore empty bracket pairs while splitting. This avoids very weirdly @@ -1011,6 +1329,7 @@ Glued together by [Łukasz Langa](mailto:lukasz@langa.pl). Maintained with [Carol Willing](mailto:carolcode@willingconsulting.com), [Carl Meyer](mailto:carl@oddbird.net), +[Jelle Zijlstra](mailto:jelle.zijlstra@gmail.com), [Mika Naylor](mailto:mail@autophagy.io), and [Zsolt Dollenstein](mailto:zsol.zsol@gmail.com). @@ -1019,30 +1338,17 @@ Multiple contributions by: * [Artem Malyshev](mailto:proofit404@gmail.com) * [Christian Heimes](mailto:christian@python.org) * [Daniel M. Capella](mailto:polycitizen@gmail.com) -* [Eli Treuherz](mailto:eli.treuherz@cgi.com) +* [Eli Treuherz](mailto:eli@treuherz.com) * Hugo van Kemenade * [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) +* [Miroslav Shubernetskiy](mailto:miroslav@miki725.com) +* [Neraste](neraste.herr10@gmail.com) * [Osaetin Daniel](mailto:osaetindaniel@gmail.com) -* [Peter Bengtsson](mailto:peterbe@mozilla.com) +* [Peter Bengtsson](mailto:mail@peterbe.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)** +* [Chuck Wooters](mailto:chuck.wooters@microsoft.com)