increment fix version and append snapshot

#!/bin/bash
function is_integer {
    test "$1" && printf '%f' "$1" >/dev/null 2>/dev/null;
}


function increment_fix_version_with_snapshot {
    currentVersion="$1"
    if [ $(echo "$currentVersion" | egrep "SNAPSHOT$") ]; then
        echo "$currentVersion"
    else
        currentFixVersion="$(echo "$currentVersion" | awk -F '.' '{print $NF}')"
        if ( is_integer $currentFixVersion ); then
            fixVersion="$(echo "$currentVersion" | awk -F '.' '{print $NF+1}')"
            majorMinor="$(echo "$currentVersion" | sed -e 's:\.[0-9]*$::')"
            echo "${majorMinor}.${fixVersion}-SNAPSHOT"
        else
            echo "${currentVersion}.0-SNAPSHOT"
        fi
    fi
}

increment_fix_version_with_snapshot "$1"