https://github.com/github/hub/issues/494#issuecomment-310274717

.bashrc

git() {
  bold="$(tput bold)"
  black="$(tput setaf 0)"
  red="$(tput setab 1)"
  yellow="$(tput setab 3)"
  cyan="$(tput setaf 6)"
  reset="$(tput sgr0)"
  if [ "$1" != delete ]; then
    hub "$@"
    return
  fi
  if [ -z "$3" ]; then
    echo 'No repository slug or repository namespace given.'
    return 1
  fi
  if ! command -v gcli &> /dev/null; then
    echo 'gcli is not available. run: gem install github_cli'
    return 1
  fi
  GCLI_USER="$(gcli config user.login)"
  if [ -z "$GCLI_USER" ]; then
    echo 'gcli user.login config is not set. see: gcli help config'
    return 1
  fi
  echo
  echo 'Are you ABSOLUTELY sure?'
  echo
  echo "${yellow}${black}                                                           ${reset}"
  echo "${yellow}${black} Unexpected bad things will happen if you don't read this! ${reset}"
  echo "${yellow}${black}                                                           ${reset}"
  echo
  echo "This action ${bold}CANNOT${reset} be undone. This will permanently delete the"
  echo "${bold}${2}/${3}${reset} repository, wiki, issues,"
  echo 'and comments, and remove all team associations.'
  echo
  read -p "$(echo -e 'Please type in the name of the repository to confirm.\n\b')"
  echo
  if [[ "$REPLY" == "${2}/${3}" ]]; then
    whitespace='                                                     '
    read -p "$(echo -e "${red} ${whitespace} ${reset}\n${bold}${red} I understand the consequences, delete this repository ${reset}\n${red} ${whitespace} ${reset} ${bold}[yN]${reset}")" -n 1
    echo
    if [[ "$REPLY" =~ ^[Yy]$ ]]; then
      success="$(gcli repo "$@")"
      if [[ "$success" =~ 204 ]]; then
        echo
        echo "${cyan}Your repository \"${2}/${3}\" was successfully deleted.${reset}"
        echo
      fi
    fi
  fi
}