ESLint git commit hook

commit-msg

#!/bin/bash
files=$(git diff --cached --name-only | grep '\.js$')

# Prevent ESLint help message if no files matched
if [[ $files = "" ]] ; then
  exit 0
fi

echo $files | xargs eslint

rc=$?
if [[ $rc != 0 ]] ; then
  echo "ESLint check failed, commit denied"
  exit $rc
fi

I think you could use git diff --staged --diff-filter=AM --name-only to shorten down file status selection

One liner for using at package.json:

"lint-staged": "eslint `git diff --staged --diff-filter=AM --name-only | grep .js$ | tr '\n' ' '`"

It runs like eslint [file1] [file2] [file3] [etc] for all staged added/modified files