#!/usr/bin/env bash
# MIT © Sindre Sorhus - sindresorhus.com


changed_files="$(git diff-tree -r --name-only --no-commit-id ORIG_HEAD HEAD)"

check_run() {
  echo "$changed_files" | grep --quiet "$1" && eval "$2"
}

check_asset_run() {
  echo "$changed_files" | grep --quiet "javascripts" && eval "$1" 
}

# Example usage
# In this example it's used to run `npm install` if package.json changed and `bower install` if `bower.json` changed.
check_run package.json "npm install"
check_run bower.json "bower install"

# run webpack
# if a javascript file changed
check_asset_run "node node_modules/webpack/bin/webpack.js"


# to install
# curl -O https://gist.github.com/blainekasten/5dae2a34b14ffa56e438/raw/ef838f17c81c357500278c300b8322964ae508cd/post-merge && chmod +x post-merge && mv post-merge .git/hooks/