Re: [PATCH 2/2] lock_ref_sha1_basic: handle REF_NODEREF with invalid refs

Jeff King [off-list ref] writes:

So instead, we attempt to resolve HEAD fully to get the old
sha1, and only if that fails do we fallback to a
non-recursive resolution. We lose nothing to the fallback,
since we know the ref cannot be resolved, and thus we have
no old sha1 in the first place. And we still get the benefit
of the d/f-checking for the symref itself.

This does mean an extra round of filesystem lookups in some
cases, but they should be rare. It only kicks in with
REF_NODEREF, and then only when the existing ref cannot be
resolved.

Makes perfect sense to me.  Thanks.