clean_branches.sh

#!/usr/bin/env bash

set -e

function prompt() {
    B="$1"

    read -p 'Delete? [y/n/s] ' result
    case "$result" in
        y)
            git branch -D "$B"
            ;;
        s)
            git show "$B"
            prompt "$B"
            ;;
        n)
            echo
            ;;
    esac
}

# This assumes that you prefix your branch names with your username
for B in $(git branch | grep "$USER"); do
    git log -n 1 "$B"
    prompt "$B"
done