Use this as your `.git/hooks/pre-commit` to enforce ESLint-ing for your JavaScript code. Modify the grep filtering to customize your whitelist. Other examples of ESLint pre-commit hooks exist online, but many seemed too complicated for what I was looking for. Enjoy!

eslint-pre-commit.bash

#!/usr/bin/env bash

################################################################################
# This script will run ESLint over all staged files with js or jsx extensions.
# Author: William Carroll
################################################################################

for file in $(git diff --name-only --cached | grep -E '\.jsx?$'); do
  npx eslint ${file}
done

Realizing that it is more performant to run:

npx eslint $(git diff --name-only --cached --diff-filter=d | grep -E '\.jsx?$')

This allows ESLint to handle the file batching, which it could do better than serially. It also uses the --diff-filter option to blacklist deleted files, since these cannot be linted.