Re: [PATCH 4/5] difftool: make --gui, --tool and --extcmd exclusive

> In git-difftool, these options specify which tool to ultimately run. As
> a result, they are logically conflicting. Explicitly disallow these
> options from being used together.
>
> Signed-off-by: Denton Liu <liu.denton@gmail.com>
> ---
> diff --git a/builtin/difftool.c b/builtin/difftool.c
> @@ -731,6 +731,15 @@ int cmd_difftool(int argc, const char **argv, const char *prefix)
> +       if (use_gui_tool)
> +               count++;
> +       if (difftool_cmd)
> +               count++;
> +       if (extcmd)
> +               count++;
> +       if (count > 1)
> +               die(_("--gui, --tool and --extcmd are exclusive"));