blog/content/posts/git-tips-lint-test-precommit-hook.md

---
title: "Git Tips - Lint + Test Pre-commit Hook"
date: 2020-01-01T21:00:39Z
tags: [git, bash]
---

One of my favorite inventions is a `pre-commit` hook that auto runs test and lint commands from a `makefile` or 
`package.json` if they're found:

```bash {linenos=table}
#!/usr/bin/env bash

if [ -f "$PWD/makefile" ] && [ ! -z "$(cat $PWD/makefile | grep '^lint:')" ]; then
    echo "running make lint"
    make lint
elif [ -f "$PWD/package.json" ] && [ ! -z "$(cat $PWD/package.json | grep "^\"lint\":")" ]; then
    echo "running npm run lint"
    npm run lint
fi

if [ -f "$PWD/makefile" ] && [ ! -z "$(cat $PWD/makefile | grep '^test:')" ]; then
    echo "running make test"
    make test
elif [ -f "$PWD/package.json" ] && [ ! -z "$(cat $PWD/package.json | grep "^\"test\":")" ]; then
    echo "running npm run test"
    npm run test
fi
```

The `/usr/bin/env bash` piece ensures that the script has access to all of the environment variables you expect in your 
regular shell.

If the test or lint command fails then the `git commit` command fails. If I absolutely need to commit something in spite
of the lint/test results I can do `git commit --no-verify` to skip the `pre-commit` hook.