X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/450983e33309cdd8b6ad3849ee86e8b5b3903706..3b72ed0d4809a4f485891d0b565379217cb47e9f:/README.md diff --git a/README.md b/README.md index 3becfd3..7be8093 100644 --- a/README.md +++ b/README.md @@ -6,7 +6,8 @@ - + +
@@ -34,6 +35,7 @@ Try it out now using the [Black Playground](https://black.now.sh). **[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)** | @@ -79,6 +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 @@ -96,8 +100,8 @@ Options: 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/] + build/|buck-out/|dist/|_build/|\.eggs/|\.git/| + \.hg/|\.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. @@ -139,7 +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. @@ -233,13 +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 ] ``` @@ -275,7 +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". @@ -353,8 +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. @@ -370,6 +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 @@ -529,6 +548,8 @@ 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 @@ -552,7 +573,8 @@ py36 = true include = '\.pyi?$' exclude = ''' /( - \.git + \.eggs + | \.git | \.hg | \.mypy_cache | \.tox @@ -640,7 +662,7 @@ $ where black 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. @@ -654,7 +676,7 @@ Configuration: 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): @@ -705,7 +727,7 @@ Use the [Python extension](https://marketplace.visualstudio.com/items?itemName=m Use [sublack plugin](https://github.com/jgirardet/sublack). -### IPython Notebook Magic +### Jupyter Notebook Magic Use [blackcellmagic](https://github.com/csurfer/blackcellmagic). @@ -720,7 +742,7 @@ the [Python Language Server](https://github.com/palantir/python-language-server) ### Atom/Nuclide -Use [atom-black](https://github.com/hauntsaninja/atom-black). +Use [python-black](https://atom.io/packages/python-black). ### Other editors @@ -737,6 +759,78 @@ 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 @@ -771,9 +865,12 @@ location of the file depends on the *Black* version and the system on which *Bla is run. The file is non-portable. The standard location on common operating systems is: -* Windows: `C:\\Users\