Simple script to determine if current git repo is on master (or specified branch)

is-on-master-branch.sh

#!/bin/sh
# get the current branch name
branchName=$(git symbolic-ref --short HEAD)
# get the branch name to match from params
# if no params, use `master`
if [ "$1" != "" ]; then
    masterBranch="$1"
else
    masterBranch="master"
fi
# success if they match, error if not
if [ "$branchName" = "$masterBranch" ]; then
    echo SUCCESS: You are on "$branchName"
    exit 0
else
    echo ERROR: You are not on "$masterBranch", you are on "$branchName"
    exit 1
fi