How to have the special toolbox prompt for fish shell?

fish_toolbx.md

So if you happen to use fish shell for your toolbox container environment, you should set the fish_prompt by modify ~/.config/fish/config.fish:

if status is-interactive
  # Commands to run in interactive sessions can go here
  function is_toolbox
    if test -f /run/.toolboxenv
      set toolbox_name (grep -E '^name="' /run/.containerenv | cut -d \" -f 2)
      echo " ❱ $toolbox_name"
    end
  end

  set TOOLBOX_NAME (is_toolbox)
  function fish_prompt
    if test -n "$TOOLBOX_NAME"
      set_color magenta
      echo -n -e "\n⬢ "
      set_color normal
      echo -n "["(whoami)"@"(hostname)"$TOOLBOX_NAME "(prompt_pwd)"]\$ "
    else
      set_color normal
      echo -n "["(whoami)"@"(hostname)" "(prompt_pwd)"]\$ "
    end
  end
end