Subject: Re: Unexpected exit code for --help with rev-parse --parseopt

From: "brian m. carlson" <[email-masked]>
Date: Sun, 15 Mar 2026 16:59:48 +0000

On 2026-03-15 at 03:14:47, Jeff King wrote:
> So the calling program runs that cat command. And I think what you
> really want is to tack "exit 0" onto the end of that output, which would
> tell the callers to exit. Something like this:
> 
> diff --git a/parse-options.c b/parse-options.c
> index a676da86f5..b990f38419 100644
> --- a/parse-options.c
> +++ b/parse-options.c
> @@ -1473,8 +1473,10 @@ static enum parse_opt_result usage_with_options_internal(struct parse_opt_ctx_t
>  	}
>  	fputc('\n', outfile);
>  
> -	if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL)
> +	if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL) {
>  		fputs("EOF\n", outfile);
> +		fputs("exit 0\n", outfile);
> +	}
>  
>  	return PARSE_OPT_HELP;
>  }

Yeah, I did some poking around, saw the heredoc, and came to the same
conclusion that this was a viable solution.  Since we both seem to agree
that this is a good solution and it also has the advantage of being
backward compatible (in that nobody has to change their code to get the
new behaviour[0]), this seems like the best option.

> And then you don't even need to change the exit code of rev-parse itself
> (since we'd never hit the "exit $?" that the caller tacks on in case of
> failure). Though I think it might be reasonable to switch it to 0
> anyway.

I can do that as well, even though I think that is actually
substantially more complicated than the first part.  I'll write up a
bunch of new tests for these cases in addition.

Thanks for a sober second opinion.

[0] As we all know, sometimes one has to use older systems and having
scripts break on older systems needlessly is quite inconvenient.
-- 
brian m. carlson (they/them)
Toronto, Ontario, CA