X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/52fda8b0e9e52e94aae6cb3170c9b1b492a2d8b4..c667b85a7f8bb599f13fa169cb11a0dcc3eb9d98:/README.md?ds=sidebyside diff --git a/README.md b/README.md index e2f91ef..3f62eec 100644 --- a/README.md +++ b/README.md @@ -3,10 +3,10 @@
@@ -14,7 +14,7 @@ *Black* is the uncompromising Python code formatter. By using it, you -agree to cease control over minutiae of hand-formatting. In return, +agree to cede control over minutiae of hand-formatting. In return, *Black* gives you speed, determinism, and freedom from `pycodestyle` nagging about formatting. You will save time and mental energy for more important matters. @@ -74,7 +74,7 @@ Options: * it will read from standard input and write to standard output if `-` is used as the filename; * it only outputs messages to users on standard error; -* exits with code 0 unless an internal error occured (or `--check` was +* exits with code 0 unless an internal error occurred (or `--check` was used). @@ -106,9 +106,9 @@ the same effect, as a courtesy for straddling code. *Black* ignores previous formatting and applies uniform horizontal and vertical whitespace to your code. The rules for horizontal -whitespace are pretty obvious and can be summarized as: do whatever -makes `pycodestyle` happy. The coding style used by *Black* can be -viewed as a strict subset of PEP 8. +whitespace can be summarized as: do whatever makes `pycodestyle` happy. +The coding style used by *Black* can be viewed as a strict subset of +PEP 8. As for vertical whitespace, *Black* tries to render one full expression or simple statement per line. If this fits the allotted line length, @@ -176,6 +176,14 @@ between two distinct sections of the code that otherwise share the same indentation level (like the arguments list and the docstring in the example above). +If a line of "from" imports cannot fit in the allotted length, it's always split +into one per line. Imports tend to change often and this minimizes diffs, as well +as enables readers of code to easily find which commit introduced a particular +import. This exception 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. + ### Line length @@ -218,10 +226,7 @@ bother you if you overdo it by a few km/h". *Black* avoids spurious vertical whitespace. This is in the spirit of PEP 8 which says that in-function vertical whitespace should only be -used sparingly. One exception is control flow statements: *Black* will -always emit an extra empty line after ``return``, ``raise``, ``break``, -``continue``, and ``yield``. This is to make changes in control flow -more prominent to readers of your code. +used sparingly. *Black* will allow single empty lines inside functions, and single and double empty lines on module level left by the original editors, except @@ -269,6 +274,11 @@ keep it. and `'''`). It will replace the latter with the former as long as it does not result in more backslash escapes than before. +*Black* also standardizes string prefixes, making them always lowercase. +On top of that, if your code is already Python 3.6+ only or it's using +the `unicode_literals` future import, *Black* will remove `u` from the +string prefix as it is meaningless in those scenarios. + The main reason to standardize on a single form of quotes is aesthetics. Having one kind of quotes everywhere reduces reader distraction. It will also enable a future version of *Black* to merge consecutive @@ -298,6 +308,19 @@ This behaviour may raise ``W503 line break before binary operator`` warnings in style guide enforcement tools like Flake8. Since ``W503`` is not PEP 8 compliant, you should tell Flake8 to ignore these warnings. +### Slices + +PEP 8 [recommends](https://www.python.org/dev/peps/pep-0008/#whitespace-in-expressions-and-statements) +to treat ``:`` in slices as a binary operator with the lowest priority, and to +leave an equal amount of space on either side, except if a parameter is omitted +(e.g. ``ham[1 + 1 :]``). It also states that for extended slices, both ``:`` +operators have to have the same amount of spacing, except if a parameter is +omitted (``ham[1 + 1 ::]``). *Black* enforces these rules consistently. + +This behaviour may raise ``E203 whitespace before ':'`` warnings in style guide +enforcement tools like Flake8. Since ``E203`` is not PEP 8 compliant, you should +tell Flake8 to ignore these warnings. + ### Parentheses Some parentheses are optional in the Python grammar. Any expression can @@ -309,6 +332,11 @@ interesting cases: - `for (...) in (...):` - `assert (...), (...)` - `from X import (...)` +- assignments like: + - `target = (...)` + - `target: type = (...)` + - `some, *un, packing = (...)` + - `augmented += (...)` In those cases, parentheses are removed when the entire statement fits in one line, or if the inner expression doesn't have any delimiters to @@ -391,7 +419,7 @@ Python version and automatically installs *Black*. You can upgrade it later by calling `:BlackUpgrade` and restarting Vim. If you need to do anything special to make your virtualenv work and -install *Black* (for example you want to run a version from master), just +install *Black* (for example you want to run a version from master), create a virtualenv manually and point `g:black_virtualenv` to it. The plugin will use it. @@ -411,6 +439,10 @@ Use [joslarson.black-vscode](https://marketplace.visualstudio.com/items?itemName Use [sublack plugin](https://github.com/jgirardet/sublack). +### IPython Notebook Magic + +Use [blackcellmagic](https://github.com/csurfer/blackcellmagic). + ### Other editors Atom/Nuclide integration is planned by the author, others will @@ -458,9 +490,9 @@ 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\