Remove duplicate ref matches in fetch

If multiple refspecs matched the same ref, the update would be
processed multiple times. Now having the same destination for the same
source has no additional effect, and having the same destination for
different sources is an error.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/remote.c b/remote.c
index e7d735b98a..e2ca4d32ba 100644
--- a/remote.c
+++ b/remote.c
@@ -380,6 +380,33 @@ int for_each_remote(each_remote_fn fn, void *priv)
 	return result;
 }
 
+void ref_remove_duplicates(struct ref *ref_map)
+{
+	struct ref **posn;
+	struct ref *next;
+	for (; ref_map; ref_map = ref_map->next) {
+		if (!ref_map->peer_ref)
+			continue;
+		posn = &ref_map->next;
+		while (*posn) {
+			if ((*posn)->peer_ref &&
+			    !strcmp((*posn)->peer_ref->name,
+				    ref_map->peer_ref->name)) {
+				if (strcmp((*posn)->name, ref_map->name))
+					die("%s tracks both %s and %s",
+					    ref_map->peer_ref->name,
+					    (*posn)->name, ref_map->name);
+				next = (*posn)->next;
+				free((*posn)->peer_ref);
+				free(*posn);
+				*posn = next;
+			} else {
+				posn = &(*posn)->next;
+			}
+		}
+	}
+}
+
 int remote_has_url(struct remote *remote, const char *url)
 {
 	int i;