make get_short_ref a public function

Often we want to shorten a full ref name to something "prettier"
to show a user. For example, "refs/heads/master" is often shown
simply as "master", or "refs/remotes/origin/master" is shown as
"origin/master".

Many places in the code use a very simple formula: skip common
prefixes like refs/heads, refs/remotes, etc. This is codified in
the prettify_ref function.

for-each-ref has a more correct (but more expensive) approach:
consider the ref lookup rules, and try shortening as much as
possible while remaining unambiguous.

This patch makes the latter strategy globally available as
shorten_unambiguous_ref.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/refs.h b/refs.h
index 68c2d16d53..2d0f961c7c 100644
--- a/refs.h
+++ b/refs.h
@@ -80,6 +80,7 @@ extern int for_each_reflog(each_ref_fn, void *);
 extern int check_ref_format(const char *target);
 
 extern const char *prettify_ref(const struct ref *ref);
+extern char *shorten_unambiguous_ref(const char *ref);
 
 /** rename ref, return 0 on success **/
 extern int rename_ref(const char *oldref, const char *newref, const char *logmsg);