Automatically format your javascript files on commit using Prettier

I recently fell in love with prettier. Prettier is an opinionated code formatter. Having consistently formatted code is very pleasant feeling for me and having formatting done automatically? Woah! The best part is that you can easily run prettier on git commit. That way you can write messy code and it will get cleaned up automatically. Let's do it.

By combining three packages we can create pre-commit git hook that will transform javascript files using prettier. Those packages are lint-staged, pre-commit and prettier. To install them run npm install --save-dev lint-staged pre-commit prettier.

Then add following keys to your package.json.

  "scripts": {
    "lint:staged": "lint-staged"
  "lint-staged": {
    "*.js": ["prettier --write --single-quote --trailing-comma=all", "git add"]
  "pre-commit": "lint:staged"

Now when you commit you code you should see ✔ Running tasks for *.js message.

$ git commit -m 'Initial commit'
 ✔ Running tasks for *.js
[master (root-commit) 7da3cc3] Initial commit
 13 files changed, 4841 insertions(+)