Pre-commit

The pre-commit script found in the local git repository (.git/hooks/pre-commit) can be any executable and will run before a git commit. A useful use case is to check the formatting of code. N.B it is not best practice to modify files in the pre-commit as tempting as it might be, since you may not always want the files to change and this can be frustrating. It is better practice to abort the commit (non-zero return from pre-commit) and warn why. If, after being warned, you want to commit anyway, pass --no-verify to git commit.

Example

An example pre-commit script might be the following:

#!/bin/bash

# Exit on any fail and prevent commit
set -e

for file in $(git diff --cached --name-only --diff-filter=d | grep "\.py$")
do
  black --check $file
done