X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/6695fd892f8f1a9e0d3879423bb0361e07eedd24..f6393a20fc0f382c6bab545f8f60ec8e10d5e099:/README.md?ds=inline diff --git a/README.md b/README.md index 5a9d6ea..5bf6f06 100644 --- a/README.md +++ b/README.md @@ -61,36 +61,41 @@ black {source_file_or_directory} _Black_ doesn't provide many options. You can list them by running `black --help`: ```text -black [OPTIONS] [SRC]... +Usage: black [OPTIONS] [SRC]... + + The uncompromising code formatter. Options: -c, --code TEXT Format the code passed in as a string. -l, --line-length INTEGER How many characters per line to allow. [default: 88] + -t, --target-version [py27|py33|py34|py35|py36|py37|py38] Python versions that should be supported by Black's output. [default: per-file auto- detection] - --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. Deprecated; use - --target-version instead. [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 reformatted. Return code 123 means + would be reformatted. Return code 123 means there was an internal error. + --diff Don't write the files back, just output a diff for each file on stdout. + + --color / --no-color Show colored diff. Only applies when + `--diff` is given. + --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. An empty value means @@ -99,6 +104,7 @@ Options: on all platforms (Windows, too). Exclusions are calculated first, inclusions later. [default: \.pyi?$] + --exclude TEXT A regular expression that matches files and directories that should be excluded on recursive searches. An empty value means no @@ -106,16 +112,23 @@ Options: directories on all platforms (Windows, too). Exclusions are calculated first, inclusions later. [default: /(\.eggs|\.git|\.hg|\.mypy - _cache|\.nox|\.tox|\.venv|_build|buck- + _cache|\.nox|\.tox|\.venv|\.svn|_build|buck- out|build|dist)/] + + --force-exclude TEXT Like --exclude, but files and directories + matching this regex will be excluded even + when they are passed explicitly as arguments + -q, --quiet Don't emit non-error messages to stderr. - Errors are still emitted, silence those with + Errors are still emitted; silence those with 2>/dev/null. + -v, --verbose Also emit messages to stderr about files that were not changed or were ignored due to --exclude=. + --version Show the version and exit. - --config PATH Read configuration from PATH. + --config FILE Read configuration from PATH. -h, --help Show this message and exit. ``` @@ -127,6 +140,16 @@ _Black_ is a well-behaved Unix-style command-line tool: - it only outputs messages to users on standard error; - exits with code 0 unless an internal error occurred (or `--check` was used). +### Using _Black_ with other tools + +While _Black_ enforces formatting that conforms to PEP 8, other tools may raise warnings +about _Black_'s changes or will overwrite _Black_'s changes. A good example of this is +[isort](https://pypi.org/p/isort). Since _Black_ is barely configurable, these tools +should be configured to neither warn about nor overwrite _Black_'s changes. + +Actual details on _Black_ compatible configurations for various tools can be found in +[compatible_configs](https://github.com/psf/black/blob/master/docs/compatible_configs.md). + ### NOTE: This is a beta product _Black_ is already [successfully used](#used-by) by many projects, small and big. It @@ -215,6 +238,69 @@ def very_important_function( ... ``` +_Black_ prefers parentheses over backslashes, and will remove backslashes if found. + +```py3 +# in: + +if some_short_rule1 \ + and some_short_rule2: + ... + +# out: + +if some_short_rule1 and some_short_rule2: + ... + + +# in: + +if some_long_rule1 \ + and some_long_rule2: + ... + +# out: + +if ( + some_long_rule1 + and some_long_rule2 +): + ... + +``` + +Backslashes and multiline strings are one of the two places in the Python grammar that +break significant indentation. You never need backslashes, they are used to force the +grammar to accept breaks that would otherwise be parse errors. That makes them confusing +to look at and brittle to modify. This is why _Black_ always gets rid of them. + +If you're reaching for backslashes, that's a clear signal that you can do better if you +slightly refactor your code. I hope some of the examples above show you that there are +many ways in which you can do it. + +However there is one exception: `with` statements using multiple context managers. +Python's grammar does not allow organizing parentheses around the series of context +managers. + +We don't want formatting like: + +```py3 +with make_context_manager1() as cm1, make_context_manager2() as cm2, make_context_manager3() as cm3, make_context_manager4() as cm4: + ... # nothing to split on - line too long +``` + +So _Black_ will now format it like this: + +```py3 +with \ + make_context_manager(1) as cm1, \ + make_context_manager(2) as cm2, \ + make_context_manager(3) as cm3, \ + make_context_manager(4) as cm4 \ +: + ... # backslashes and an ugly stranded colon +``` + You might have noticed that closing brackets are always dedented and that a trailing comma is always added. Such formatting produces smaller diffs; when you add or remove an element, it's always just one line. Also, having the closing bracket dedented provides a @@ -621,8 +707,11 @@ file hierarchy. ### Emacs -Use [proofit404/blacken](https://github.com/proofit404/blacken) or -[Elpy](https://github.com/jorgenschaefer/elpy). +Options include the following: + +- [purcell/reformatter.el](https://github.com/purcell/reformatter.el) +- [proofit404/blacken](https://github.com/proofit404/blacken) +- [Elpy](https://github.com/jorgenschaefer/elpy). ### PyCharm/IntelliJ IDEA @@ -797,6 +886,55 @@ default. On macOS with Homebrew run: `brew install vim`. When building Vim from use: `./configure --enable-python3interp=yes`. There's many guides online how to do this. +**I get an import error when using _Black_ from a virtual environment**: If you get an +error message like this: + +```text +Traceback (most recent call last): + File "", line 63, in + File "/home/gui/.vim/black/lib/python3.7/site-packages/black.py", line 45, in + from typed_ast import ast3, ast27 + File "/home/gui/.vim/black/lib/python3.7/site-packages/typed_ast/ast3.py", line 40, in + from typed_ast import _ast3 +ImportError: /home/gui/.vim/black/lib/python3.7/site-packages/typed_ast/_ast3.cpython-37m-x86_64-linux-gnu.so: undefined symbool: PyExc_KeyboardInterrupt +``` + +Then you need to install `typed_ast` and `regex` directly from the source code. The +error happens because `pip` will download [Python wheels](https://pythonwheels.com/) if +they are available. Python wheels are a new standard of distributing Python packages and +packages that have Cython and extensions written in C are already compiled, so the +installation is much more faster. The problem here is that somehow the Python +environment inside Vim does not match with those already compiled C extensions and these +kind of errors are the result. Luckily there is an easy fix: installing the packages +from the source code. + +The two packages that cause the problem are: + +- [regex](https://pypi.org/project/regex/) +- [typed-ast](https://pypi.org/project/typed-ast/) + +Now remove those two packages: + +```console +$ pip uninstall regex typed-ast -y +``` + +And now you can install them with: + +```console +$ pip install --no-binary :all: regex typed-ast +``` + +The C extensions will be compiled and now Vim's Python environment will match. Note that +you need to have the GCC compiler and the Python development files installed (on +Ubuntu/Debian do `sudo apt-get install build-essential python3-dev`). + +If you later want to update _Black_, you should do it like this: + +```console +$ pip install -U black --no-binary regex,typed-ast +``` + ### Visual Studio Code Use the @@ -1047,13 +1185,14 @@ other hand, if your answer is "because I don't like a particular formatting" the not ready to embrace _Black_ yet. Such changes are unlikely to get accepted. You can still try but prepare to be disappointed. -More details can be found in [CONTRIBUTING](CONTRIBUTING.md). +More details can be found in +[CONTRIBUTING](https://github.com/psf/black/blob/master/CONTRIBUTING.md). ## Change Log The log's become rather long. It moved to its own file. -See [CHANGES](CHANGES.md). +See [CHANGES](https://github.com/psf/black/blob/master/CHANGES.md). ## Authors