shell脚本判断git远端是否有更新

git remote update

UPSTREAM=${1:-'@{u}'}
LOCAL=$(git rev-parse HEAD)
REMOTE=$(git rev-parse "$UPSTREAM")
BASE=$(git merge-base HEAD "$UPSTREAM")
S
if [ $LOCAL = $REMOTE ]; then
    echo "Up-to-date"
elif [ $LOCAL = $BASE ]; then
    echo "Need to pull"
elif [ $REMOTE = $BASE ]; then
    echo "Need to push"
else
    echo "Diverged"