Git: check if a branch is sync'd with a branch of the same name in a remote repo e.g. `check-remote-sync development origin`. Returns nothing if in sync.

check-remote-sync.sh

#!/bin/bash

LOCAL_BRANCH=$1
REMOTE_BRANCH="${2:-origin}/$1"

if [ x"$(git rev-parse $LOCAL_BRANCH)" != x"$(git rev-parse $REMOTE_BRANCH)" ]
then
    echo "$LOCAL_BRANCH is not in sync with $REMOTE_BRANCH. You may want to rebase or push first."
fi