VSCode: Setting line lengths in the Black Python code formatter

#vscode #python #webdev #tutorial

The docs for the Black Python code formatter say that the formatter "is not configurable". This is largely true, but if you have Black set up to work in VSCode, you can configure the line length.

In VSCode, go 'Code -> Preferences -> Settings' and search for "python formatting black args".

Add two separate arguments, in this order: --line-length and n, where "n" is your desired number of allowed characters per line:

A few notes about line lengths in Python:

PEP8 recommends a line length of 79 characters (72 for docstrings)
Black sets line lengths to 88 characters by default
The Django docs recommend a maximum line length of 119 characters (79 for docstrings)

If you are working on a shared project with a team, consider bypassing the VSCode settings entirely, and setting line lengths via the project's pyproject.toml:



[tool.black]
line-length = 119

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Top comments (9)

milkator • May 31 • Edited

I'm setting the arguments via pyproject.toml and had the problem, that the line-length was not reformatted properly.
After a while, I found out that I have to restart the format server!

If you have the same problem...simply do this:

'Ctrl + Shift + P' -> '> Black Formatter: Restart Server'

rrakso • Oct 10

Thank you!!!

mrx • Sep 29 '21

fyi, can also add this to your .vscode folder > settings.json

{
    "python.formatting.provider": "black",
    "python.formatting.blackArgs": ["--line-length", "120"],
    "python.linting.enabled": true
}

Jordan Haines • May 2 '20 • Edited

Definitely going to reference this very time I start a new project -- right after I re-learn that setting max line length in .pylintrc is not a substitute for the setting Adam's proposed here. Thanks Adam!