Bash: safe git commit -am

#!/bin/bash

# $1 -- [optional] custom commit author
fart () {

    git add .
    RETVAL=$?
    if [ $RETVAL -ne 0 ]; then
        echo 'Some shit happened! (git add .)' 1>&2
        return $RETVAL
    fi

    git status
    RETVAL=$?
    if [ $RETVAL -ne 0 ]; then
        echo 'Some shit happened! (git status)' 1>&2
        return $RETVAL
    fi

    echo 'Enter your commit message or leave it empty if you did something wrong.'
    echo -n 'Commit message: '
    read msg
    local clear_msg=$(echo "$msg" | sed -e 's/\(^\s\+\|\s\+$\)//g')
    if [ "x$clear_msg" == "x" ]; then
        echo 'Commit is cancelled (because commit message is empty)' 2>&1
        return 1
    else
        if [ "x$1" == "x" ]; then
            git commit -m "$clear_msg"
        else
            git commit -m "$clear_msg" --author="$1"
        fi
        return $?
    fi
}