Re: [PATCH 6/6] sha1_name: implement @{push} shorthand

Jeff King [off-list ref] writes:

quoted

quoted

+static char *tracking_ref_for(struct remote *remote, const char *refname)
+{
+	char *ret;
+
+	ret = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
+	if (!ret)
+		die(_("@{push} has no local tracking branch for remote '%s'"),
+		    refname);

I would imagine that it would be very plausible that anybody with a
specific remote and the name of the ref that appears on that remote
would want to learn the local name of the remote-tracking ref we use
to track it.

I am not sure I understand. We do _not_ have a local name we use to
track it. That is the error. I can print "remote %s does not have branch
%s", if that is what you mean.

No, I am not saying we should not detect an error.

quoted

But the error message limits the callers only to those who are
involved in @{push} codepath.  Shouldn't the error check be done in
the caller instead, anticipating the day this useful function ceases
to be static?

Is it really a useful general function?

I often interact with this remote called 'ko'.  Do I have remote-tracking
branch to keep track of its 'master' branch, and if so, what is it?

Isn't that the question that the apply_refspecs() is answering?

If you remove the die() message,
it is literally a one-liner.

Yes, I thought I said that here...

quoted

I would suspect that such a change would make it just a one-liner,
but I think this helper that takes remote and their refname is much
easier to read than four inlined calls to apply_refspecs() that have
to spell out remote->fetch, remote->fetch_refspec_nr separately.

quoted

Perhaps we would want 

	struct refspecs {
        	int nr, alloc;
                const char **refspec;
	} fetch_refspec;

in "struct remote", instead of these two separate fields, and then
make apply_refspecs() take "struct refspecs *"?  I haven't checked
and thought enough to decide if we want "struct refspec *" also in
that new struct, though.

I think it is more complicated, as there are actually two arrays indexed
by each {fetch,push}_refspec_nr. We have "fetch_respec", which contains
the text (I assume), and then the "struct refspec".

Yeah, I thought I said that, too ;-)

So ideally those
would be stored together in a single list, but of course many helper
functions want just the "struct refspec" list. So you still end up with
two lists, but just pushed down into a single struct. I guess that's
better, but I was trying to find a bound to my refactoring rather than
touching all of the code. :-/

OK.