git-diff -B output fix.

diff --git a/sha1_name.c b/sha1_name.c
index 5fe8e5d4bf25d79c3fa76610d1617ee07c1f1e2c..c5a05faeb6b2bac74f4c5e06c5e397dc103bb190 100644 (file)
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -193,7 +193,7 @@ const char *find_unique_abbrev(const unsigned char *sha1, int len)
 
        is_null = !memcmp(sha1, null_sha1, 20);
        memcpy(hex, sha1_to_hex(sha1), 40);
-       if (len == 40)
+       if (len == 40 || !len)
                return hex;
        while (len < 40) {
                unsigned char sha1_ret[20];