denyNonFastForwards & co fail outside refs/<heads,tags>

config options receive.<denyNonFastForward, denyDeletes> do not work in nonstandard ref namespaces. I stumbled over it in refs/notes/, but the problem is general. Or if it this intentional, it is the git-config(1) doc of these options which needs fixing.

Git version 1.7.4.2.

To reproduce:

######################################################################## #!/bin/sh rm -rf hi ho

git --version

# Create initial repos
git init -q hi
(cd hi
    git config receive.denyDeletes         true
    git config receive.denyNonFastForwards true
    echo foo > foo && git add foo && git commit -q -m first foo)
git clone -q hi ho

# Make them diverge, except the checked-out branch
for r in hi ho; do
    (cd $r
	echo $r >> foo && git commit -q -m next foo
	git update-ref refs/outside/test HEAD
	git checkout -q -b br HEAD^
	# Shut up a bit
	git config advice.pushNonFastForward false
	git gc --quiet
	# For ssh push
	git update-server-info)
done

cd ho # Optional; makes no difference #git config remote.origin.pushurl localhost:`pwd`/../hi

# Can push test despite 'deny's, fails as expeceted for master:
for b in refs/outside/test refs/heads/master; do
    git push -f origin $b:$b
    git push -f origin   :$b
    echo ""
done
# Just to check: Pushing the master normal way fails the same way.
git push -f origin

######################################################################## Output:

git version 1.7.4.2
To /tmp/hi
 + 1bb5836...5bf63f8 refs/outside/test -> refs/outside/test (forced update)
To /tmp/hi
 - [deleted]         refs/outside/test

remote: error: denying non-fast-forward refs/heads/master (you should pull first)        
To /tmp/hi
 ! [remote rejected] master -> master (non-fast-forward)
error: failed to push some refs to '/tmp/hi'
remote: error: denying ref deletion for refs/heads/master        
To /tmp/hi
 ! [remote rejected] master (deletion prohibited)
error: failed to push some refs to '/tmp/hi'

remote: error: denying non-fast-forward refs/heads/master (you should pull first)        
To /tmp/hi
 ! [remote rejected] master -> master (non-fast-forward)
error: failed to push some refs to '/tmp/hi'

Hallvard B Furuseth <h.b.furuseth@usit.uio.no> writes:

I think it is very deliberate that denyNonFastForward does not check anything outside local branch namespace, because there may not even be ancestry relationship between the object a tag currently points at and the new object the tag is trying to update (think: a tag can point at a tree or a blob) and more importantly because pushing into refs/remotes/origin/* namespace (which is the right way to simulate a "git fetch" from the repository with a "git push" from outside into the repository in a firewalled environment where you cannot initiate a connection in one direction) should be allowed (just like "remote.*.fetch" line in .git/config get a leading plus sign '+' by default).

I suspect that the restriction on deny_deletes was inherited by a mindless cut & paste from the deny_non_fast_forwards codepath; I don't think of a sane rationale to justify the limitation offhand, other than "it has been wide open since November of 2008 and people may now be relying on that".