From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH v2] for-each-ref: `:short` format for `refname`
Date: Tue, 02 Sep 2008 16:10:00 -0700
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 <1220392637-24978-1-git-send-email-bert.wesarg@googlemail.com>
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	"Shawn O. Pearce" <spearce@spearce.org>
To: Bert Wesarg <bert.wesarg@googlemail.com>
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 (Bert Wesarg's message of "Tue, 2 Sep 2008 23:57:17 +0200")
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Bert Wesarg <bert.wesarg@googlemail.com> writes:

> Tries to shorten the refname to a non-ambiguous name.
> I.e. the full and the short refname points to the same object.

The definition of "ambiguity" here is wrong (see below).

> +	/* skip first rule, will always match */
> +	for (i = 0; i < nr_rules - 1; i++) {
> +		const char **p;
> +		int short_name_len;
> +
> +		if (1 != sscanf(ref->refname, scanf_fmts[nr_rules - 1 - i],
> +				short_name))
> +			continue;
> +
> +		short_name_len = strlen(short_name);
> +
> +		/* check if full and short point to the same object

Style?

> +		 * by checking all rules in forward direction
> +		 */

I think this part of the code is wrong, in that it talks about what object
the ref points at.  That is not what ref ambiguity is about.

Given a tag that points at a version 1.0.0 commit, this sequence will
create:

	$ git tag foo v1.0.0^0
        $ git branch foo v1.0.0^0

ambiguous branch and tag whose names are both 'foo', even though they
point at the same thing.  The right API to use would be resolve_ref(), I
think.

Other than that, it is well done.

Although I was initially a bit surprised by the size of the patch to
implement something so (conceptually) simple, the code was easy and
straightforward to follow.

Thanks.