1 files changed, 31 insertions, 9 deletions

diff --git a/src/remote.c b/src/remote.c
index 99b5bacc0..43b34561d 100644
--- a/src/remote.c
+++ b/src/remote.c
@@ -1453,18 +1453,20 @@ static int next_head(const git_remote *remote, git_vector *refs,
 	return GIT_ITEROVER;
 }
 
-static int opportunistic_updates(const git_remote *remote, git_vector *refs, const char *msg)
+static int opportunistic_updates(const git_remote *remote, const git_remote_callbacks *callbacks,
+				 git_vector *refs, const char *msg)
 {
 	size_t i, j, k;
 	git_refspec *spec;
 	git_remote_head *head;
 	git_reference *ref;
 	git_buf refname = GIT_BUF_INIT;
-	int error;
+	int error = 0;
 
 	i = j = k = 0;
 
 	while ((error = next_head(remote, refs, &spec, &head, &i, &j, &k)) == 0) {
+		git_oid old = {{ 0 }};
 		/*
 		 * If we got here, there is a refspec which was used
 		 * for fetching which matches the source of one of the
@@ -1473,18 +1475,38 @@ static int opportunistic_updates(const git_remote *remote, git_vector *refs, con
 		 * FETCH_HEAD
 		 */
 
+		git_buf_clear(&refname);
 		if ((error = git_refspec_transform(&refname, spec, head->name)) < 0)
-			return error;
+			goto cleanup;
 
-		error = git_reference_create(&ref, remote->repo, refname.ptr, &head->oid, true, msg);
-		git_buf_free(&refname);
-		git_reference_free(ref);
+		error = git_reference_name_to_id(&old, remote->repo, refname.ptr);
+		if (error < 0 && error != GIT_ENOTFOUND)
+			goto cleanup;
+
+		if (!git_oid_cmp(&old, &head->oid))
+			continue;
 
+		/* If we did find a current reference, make sure we haven't lost a race */
+		if (error)
+			error = git_reference_create(&ref, remote->repo, refname.ptr, &head->oid, true, msg);
+		else
+			error = git_reference_create_matching(&ref, remote->repo, refname.ptr, &head->oid, true, &old, msg);
+		git_reference_free(ref);
 		if (error < 0)
-			return error;
+			goto cleanup;
+
+		if (callbacks && callbacks->update_tips != NULL) {
+			if (callbacks->update_tips(refname.ptr, &old, &head->oid, callbacks->payload) < 0)
+				goto cleanup;
+		}
 	}
 
-	return 0;
+	if (error == GIT_ITEROVER)
+		error = 0;
+
+cleanup:
+	git_buf_free(&refname);
+	return error;
 }
 
 int git_remote_update_tips(
@@ -1532,7 +1554,7 @@ int git_remote_update_tips(
 
 	/* only try to do opportunisitic updates if the refpec lists differ */
 	if (remote->passed_refspecs)
-		error = opportunistic_updates(remote, &refs, reflog_message);
+		error = opportunistic_updates(remote, callbacks, &refs, reflog_message);
 
 out:
 	git_vector_free(&refs);