git

function is_submodule() {
    local git_dir parent_git module_name path strip
    # Find the root of this git repo, then check if its parent dir is also a repo
    git_dir="$(git rev-parse --show-toplevel)"
    parent_git="$(cd "$git_dir/.." && git rev-parse --show-toplevel 2> /dev/null)"

    if [[ -n $parent_git ]]; then
        strip=$((${#parent_git} + 1))
        module_name=${git_dir:$strip}
        # List all the submodule paths for the parent repo
        while read path
        do
            if [[ "$path" != "$module_name" ]]; then continue; fi
            if [[ -d "$parent_git/$path" ]]; then
                echo $module_name
                return 0;
            fi
        done < <(cd $parent_git && git submodule --quiet foreach 'echo $path' 2> /dev/null)
    fi
    return 1
}

function parse_git_branch {
    git show > /dev/null 2>&1 || return
    P=

    SM=
    submodule=$(is_submodule)
    if [[ $? -eq 0 ]]; then
        SM="s:$submodule"
    fi
    P=$P${SM:+${P:+ }${SM}}

    BRANCH=
    ref=$(git symbolic-ref HEAD 2> /dev/null)
    if [[ $? -eq 0 ]]; then
      BRANCH="b:${ref#refs/heads/}"
    fi
    P=$P${BRANCH:+${P:+ }${BRANCH}}


    DESC="d:"$(git describe 2> /dev/null) || DESC=""
    P=$P${DESC:+${P:+ }${DESC}}

    echo "(${P}) "
}

# add to prompt by adding to .bashrc somewhere:
# PS1="\$(parse_git_branch)$PS1"