Xcode build script (Apple generic versioning tool)

build.sh

#!/usr/bin/env sh

if git diff-index --quiet HEAD --; then
    agvtool next-version -all
    agvtool new-marketing-version "$1"
    buildnum=`agvtool vers -terse`
    git add .
    git commit -m "New build: $1 ($buildnum)"
    
    if [ "$2" = "--release" ]; then
        git tag -a "$1" -m "Release $1 ($buildnum)"
        echo "Release $1 ($buildnum) is ready to build. Be sure to push your tags."
    else
        echo "$1 ($buildnum) is ready to build."
    fi
else
    echo Commit your changes before building.
fi