From: Junio C Hamano <gitster@pobox.com>
Date: Tue, 01 Jan 2013 20:38:40 GMT
Subject: Re: [PATCH 2/3] format-patch: pick up branch description when no ref is specified
Message-ID: <7v38ykbpv3.fsf@alter.siamese.dyndns.org>
In-Reply-To: <1357032655-21103-2-git-send-email-pclouds@gmail.com>

Nguyễn Thái Ngọc Duy  <pclouds@gmail.com> writes:

> find_branch_name() fails to detect "format-patch --cover-letter -3"
> where no command line arguments are given and HEAD is automatically
> added.

Nicely spotted.

That is not the only case that takes this codepath, though.

    $ git format-patch --cover-letter master..

will also give you the same (if you say it without "..", which is
the more normal invocation of the command, then the caller already
know you meant the current branch and this function is not called).

And in that case you will have two tokens on cmdline.nr, one for
"master.."  to show where he bottom is, and the other for the
implied "HEAD"; I do not think this patch is a sufficient solution
for the more general cases, but on the other hand I do not know how
much it matters.

> -	if (positive < 0)
> +	if (positive < 0) {
> +		/*
> +		 * No actual ref from command line, but "HEAD" from
> +		 * rev->def was added in setup_revisions()
> +		 * e.g. format-patch --cover-letter -12
> +		 */

That comment does not describe "positive < 0" case, but belongs to
the conditional added in this patch, no?

> +		if (!rev->cmdline.nr &&
> +		    rev->pending.nr == 1 &&
> +		    !strcmp(rev->pending.objects[0].name, "HEAD")) {
> +			const char *ref;
> +			ref = resolve_ref_unsafe("HEAD", branch_sha1, 1, NULL);
> +			if (ref && !prefixcmp(ref, "refs/heads/"))
> +				return xstrdup(ref + strlen("refs/heads/"));
> +		}
>  		return NULL;
> +	}
>  	strbuf_addf(&buf, "refs/heads/%s", rev->cmdline.rev[positive].name);
>  	branch = resolve_ref_unsafe(buf.buf, branch_sha1, 1, NULL);
>  	if (!branch ||