BASH: Reminder to 'git pull'. This function hooks into CD to remind you to 'git pull' when entering a repository directory. It will only alert you every X seconds.

BASH: Reminder to 'git pull'

cd() {    
	# Seconds between alerts: raise this 
	# number if you want to get fewer alerts
	# Default: 10 min
	alertDelay=600


	# Alert text: this is displayed when you 
	# CD into a git repo
	alertText="\n##################################################\n    This is a git repo. Don't forget to 'git pull'\n##################################################\n"


	######
	## Nothing to change beyond here
	######
  
	# Run CD command
	builtin cd $1

	# Check if current dir is repo
	git status >/dev/null 2>&1

	if [ $? == 0 ]; then
		
		# Make sure there's at least one commit before continuing
		git rev-parse HEAD &> /dev/null
		if [ $? != 0 ]; then
			return
		fi

		# If current dir is a git repo,
		# then set up tools for alert

		repoRoot="$(git rev-parse --show-toplevel)"
	
		# This is a repository identifer
		# used to track when alerts are 
		# displayed for each repo.
		repoId="$(git rev-list --parents HEAD | tail -1)"

		# This is the file containing the 
		# Unix timestamp of the last alert
		statusFile="/tmp/git-cd-alerter/$repoId"

		# Get the unix timestamp
		timestamp=$(date +%s)
		
		if [ -s $statusFile ]; then
			fileTime=$(cat $statusFile);
			timeDiff=`expr $timestamp - $fileTime`

			if [ "$timeDiff" -gt "$alertDelay" ]; then

				echo -e $alertText;
				echo $timestamp > /tmp/git-cd-alerter/$repoId

			fi

		else

			echo -e $alertText;
			mkdir -p /tmp/git-cd-alerter/
			echo $timestamp > /tmp/git-cd-alerter/$repoId

		fi

	else
		# If not, exit function now
		return
	fi

}