Subject: Re: [PATCH 5/7] grep: fix "--" rev/pathspec disambiguation

From: Brandon Williams <[email-masked]>
Date: Tue, 14 Feb 2017 10:56:21 -0800

On 02/14, Jeff King wrote:
> -	/* Check revs and then paths */
> +	/*
> +	 * We have to find "--" in a separate pass, because its presence
> +	 * influences how we will parse arguments that come before it.
> +	 */
> +	for (i = 0; i < argc; i++) {
> +		if (!strcmp(argv[i], "--")) {
> +			seen_dashdash = 1;
> +			break;
> +		}
> +	}

So this simply checks if "--" is an argument that was provided.  This
then allows grep to know ahead of time how to handle revs/paths
preceding a "--" or in the absences of the "--".  Seems sensible to me.

> +
> +	/*
> +	 * Resolve any rev arguments. If we have a dashdash, then everything up
> +	 * to it must resolve as a rev. If not, then we stop at the first
> +	 * non-rev and assume everything else is a path.
> +	 */
>  	for (i = 0; i < argc; i++) {
>  		const char *arg = argv[i];
>  		unsigned char sha1[20];
> @@ -1158,13 +1173,14 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
>  
>  		if (!strcmp(arg, "--")) {
>  			i++;
> -			seen_dashdash = 1;
>  			break;
>  		}
>  
> -		/* Stop at the first non-rev */
> -		if (get_sha1_with_context(arg, 0, sha1, &oc))
> +		if (get_sha1_with_context(arg, 0, sha1, &oc)) {
> +			if (seen_dashdash)
> +				die(_("unable to resolve revision: %s"), arg);
>  			break;
> +		}
>  
>  		object = parse_object_or_die(sha1, arg);
>  		if (!seen_dashdash)
> @@ -1172,7 +1188,10 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
>  		add_object_array_with_path(object, arg, &list, oc.mode, oc.path);
>  	}
>  
> -	/* The rest are paths */
> +	/*
> +	 * Anything left over is presumed to be a path. But in the non-dashdash
> +	 * "do what I mean" case, we verify and complain when that isn't true.
> +	 */

-- 
Brandon Williams