Little debugger for bash scripts

bashdb.sh

#!/bin/echo must be source:
# bash debugger
# Rene Devichi. https://unlicense.org

# Usage: `source bashdb.db` at the beginning of your script

# Inline version:
#   curl -sL -o /tmp/bashdb.sh https://gist.github.com/rene-d/fd2d2c37dfc1371255818d73f7b5f1db/raw/bashdb.sh
#    trap "rm -f /tmp/bashdb.sh" EXIT
#   . /tmp/bashdb.sh

# Install (assuming ~/.local/bin exists and is on your PATH)
#   curl -sL -o $HOME/.local/bin/bashdb.sh https://gist.github.com/rene-d/fd2d2c37dfc1371255818d73f7b5f1db/raw/bashdb.sh
# Use with . bashdb.sh


bashdb_continue=
bashdb_run_until=
bashdb_trap()
{
    local rc="$?"

    statusline()
    {
        local state=${1:-run}
        echo -e "(${state}) \033[97m\$?=${rc}\033[0m \033[33m${BASH_SOURCE[2]}:${BASH_LINENO[1]}\033[0m \033[33m[${FUNCNAME[2]}]\033[0m \033[32m""$BASH_COMMAND""\033[0m"
    }

    # if stdin is not a terminal, automatically continue with a delay
    if [[ ! -t 0 ]]; then
        statusline
        sleep 2
        return
    fi

    # by default do not trap shell functions
    set +o functrace

    if [[ $bashdb_continue ]]; then
        statusline
        return
    fi

    if [[ $bashdb_run_until ]]; then
        if [[ ${BASH_LINENO[0]} -lt $bashdb_run_until ]]; then
            statusline
            return;
        fi
        bashdb_run_until=
    fi

    while true; do
        statusline dbg
        read -r -n1 -s a
        case "$a" in
            ''|n) break ;;
            C) bashdb_continue=1 ; break ;;
            r|R)
                read -r -e -p "line ? " a
                if [[ $a ]]; then bashdb_run_until=$a; fi
                break
                ;;
            s)
                set -o functrace
                break
                ;;
            p|\?)
                read -r -e -p "variable ? " a
                if [[ $a ]]; then
                    echo -e "$a = \033[1;31m${!a}\033[0m"
                fi
                ;;
            e) echo -ne "\033[1;31m"; env ; echo -ne "\033[0m" ;;
            !) ${BASH} ;;
            v)
                read -r -e -p "eval> " a
                eval "$a"
                ;;
            q|Q) echo "quit"; exit 0 ;;
            *) echo -e "Unknown command \033[1;35m$a\033[0m. "\
                    "\033[1;35mn\033[0m\033[0m=next "\
                    "\033[1;35ms\033[0m=step into "\
                    "\033[1;35mr\033[0m=run until "\
                    "\033[1;35mC\033[0m=continue "\
                    "\033[1;35mp\033[0m=print "\
                    "\033[1;35me\033[0m=env "\
                    "\033[1;35m!\033[0m=shell "\
                    "\033[1;35mq\033[0m=quit "\
                    "\033[1;35mv\033[0m=eval"
        esac
    done
}
trap bashdb_trap debug