remote: avoid passing NULL to read_ref()

read_ref() can (and in test t5800, actually *does*) return NULL.
Don't pass the NULL along to read_ref().  Coincidentally, this mistake
didn't make resolve_ref() blow up, but upcoming changes to
resolve_ref() will make it less forgiving.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/transport-helper.c b/transport-helper.c
index 07131261fefeab2066636a7f83bce05796329a54..6f227e253bf638de37ce74347213657c23185afa 100644 (file)
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -446,8 +446,10 @@ static int fetch_with_import(struct transport *transport,
                        private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
                else
                        private = xstrdup(posn->name);
-               read_ref(private, posn->old_sha1);
-               free(private);
+               if (private) {
+                       read_ref(private, posn->old_sha1);
+                       free(private);
+               }
        }
        strbuf_release(&buf);
        return 0;