Subject: Re: [PATCH] name-rev: Allow to omit refs/tags/ part in --refs option when --tags used

From: Namhyung Kim <[email-masked]>
Date: Tue, 18 Jun 2013 21:24:53 +0900

2013-06-18 AM 12:53, Junio C Hamano wrote:
> Junio C Hamano <[email-masked]> writes:
>
>> Wouldn't it make more sense to see if the given pattern matches a
>> tail substring of the ref, instead of using the hardcoded "strip
>> refs/heads/, refs/tags or refs/, and then match once" logic?  That
>> way, --refs=origin/* can find refs/remotes/origin/master by running
>> fnmatch of origin/* against its substrings, i.e.
>>
>> 	refs/remotes/origin/master
>>          remotes/origin/master
>>          origin/master
>>
>> and find that the pattern matches it.
>>
>> Perhaps it is just the matter of adding something like:
>> ...
>> and then at the beginning of name_ref() do this:
>>
>> 	int can_abbreviate_output = data->name_only;
>>
>> 	if (data->tags_only && prefixcmp(path, "refs/tags/"))
>> 		return 0;
>> 	if (data->ref_filter) {
>>          	switch (subpath_matches(path, data->ref_filter)) {
>> 		case -1: /* did not match */
>> 			return 0;
>> 		default: /* matched subpath */
>> 			can_abbreviate_output = 1;
>> 			break;
>> 		case 0: /* matched fully */
>>                  	break;
>> 		}
>> 	}
>>
>> The logic before calling name_rev() will be kept as "only decide how
>> the output looks like", without mixing the unrelated "decide if we
>> want to use it" logic in.
>
> ... which may make the "call name_rev with this abbreviated path"
> logic look something like this:
>
> 	if (o && o->type == OBJ_COMMIT) {
>          	if (can_abbreviate_output)
> 			path = shorten_unambiguous_ref(path, 0);
> 		else if (!prefixcmp(path, "refs/heads/"))
> 			path = path + 11;
> 		else if (data->tags_only
> 		    && data->name_only
> 		    && !prefixcmp(path, "refs/tags/"))
> 			path = path + 10;
> 		else if (!prefixcmp(path, "refs/"))
> 			path = path + 5;
>
> 		name_rev((struct commit *) o, xstrdup(path), 0, 0, deref);
> 	}
>
>

Hmm.. I thought about it twice.

This will affects the output of `--name-only 
--refs=refs/remotes/origin/*` case.  (AFAIK it only affected to tags so 
far)  As the name_only always sets can_abbreviate_output, it'll shorten 
the name of remote ref even if it's fully matched.

  $ ./git name-rev --refs=refs/remotes/origin/* a2055c2
  a2055c2 remotes/origin/maint~642

  $ ./git name-rev --refs=refs/remotes/origin/* --name-only a2055c2
  origin/maint~642

I think it should be 'data->tags_only && data->name_only' for 
compatibility reason.

I also see that the 3rd condition of 'tags_only && name_only' turned out 
to be useless for the similar reason.  When name_only set, it'll take 
the first case so 3rd case cannot be reached. When it's not set it 
cannot take the third case too obviously.  So I'll just remove it.

Thanks,
Namhyung