Re: [PATCH 3/3] parse-opt: migrate builtin-merge-file.

> diff --git a/builtin-merge-file.c b/builtin-merge-file.c
> index 45c9853..7736fe8 100644
> --- a/builtin-merge-file.c
> +++ b/builtin-merge-file.c
> @@ -2,21 +2,44 @@

> +static int label_cb(const struct option *opt, const char *arg, int unset)
> +{
> +	static int label_count = 0;
> +	const char **names = (const char **)opt->value;
> +
> +	if (label_count >= 3)
> +		return error("too many labels on the command like");