git check-ref-format --print

git check-ref-format --print

Tolerating empty path components in ref names means each ref does
not have a unique name.  This creates difficulty for porcelains
that want to see if two branches are equal.  Add a helper associating
to each ref a canonical name.

If a user asks a porcelain to create a ref "refs/heads//master",
the porcelain can run "git check-ref-format --print refs/heads//master"
and only deal with "refs/heads/master" from then on.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>