Git hook to display notification on post-merge if certain files changed

post-merge

#!/usr/bin/env bash
#
# Save this to yourproject/.git/hooks/post-merge
#
# After a successful merge, check if bower.json, package.json
# or requirements has changed and notify the user to take
# appropriate actions.
#
# https://github.com/git/git/blob/master/Documentation/githooks.txt#L167
# This hook cannot affect the outcome of 'git merge' and is not executed,
# if the merge failed due to conflicts.
#
# Based off https://gist.github.com/sindresorhus/7996717

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

# This method checks and notifies
check_warn() {
	echo "$changed_files" | grep --quiet "$1" && echo -e "\e[1;31m$1 changed: Please run:\e[39m $2\e[0m"
}

# This method checks and runs automatically
check_run() {
	echo "$changed_files" | grep --quiet "$1" && eval "$2"
}

check_run package.json "npm install"
check_run bower.json "bower update"
check_warn requirements.txt "pip install -r requirements.txt"