A small bash script function to check if local git repository copy has changes. I use it for some deployment automation scripts.

dirty_git.sh

#!/bin/bash

#
# Checks if git repository at $1 does not have modified files
#
function is_dirty {
    GIT_DIR="$1/.git" GIT_WORK_TREE="$1" git diff --quiet
    if [[ $? == 0 ]]; then
       return 1
    else
       return 0
    fi
}

# usage example
is_dirty $1 && echo "$1 is dirty!" && exit 1