diff --git a/src/or/test.c b/src/or/test.c
index 29b6d5c097..610a297f1a 100644
--- a/src/or/test.c
+++ b/src/or/test.c
@@ -1024,6 +1024,16 @@ _test_eq_ip6(struct in6_addr *a, struct in6_addr *b, const char *e1,
     test_eq_ip6(&a1, &a2);                                              \
   } while (0)
 
+#define test_ntop6_reduces2(a,b,c) do {                                 \
+    r = tor_inet_pton(AF_INET6, a, &a1);                                \
+    test_assert(r==1);                                                  \
+    test_assert(tor_inet_ntop(AF_INET6, &a1, buf, sizeof(buf)));        \
+    test_assert(!strcmp(buf, b) || !strcmp(buf, c));                    \
+    r = tor_inet_pton(AF_INET6, b, &a2);                                \
+    test_assert(r==1);                                                  \
+    test_eq_ip6(&a1, &a2);                                              \
+  } while (0)
+
 static void
 test_ip6_helpers(void)
 {
@@ -1060,8 +1070,8 @@ test_ip6_helpers(void)
   /* === Test ntop: af_inet6 */
   test_ntop6_reduces("0:0:0:0:0:0:0:0", "::");
 
-  test_ntop6_reduces("0001:0099:BEEF:0000:0123:FFFF:0001:0001",
-                     "1:99:beef:0:123:ffff:1:1");
+  test_ntop6_reduces("0001:0099:BEEF:0006:0123:FFFF:0001:0001",
+                     "1:99:beef:6:123:ffff:1:1");
 
   test_ntop6_reduces("0:0:0:0:0:0:c0a8:0101", "::192.168.1.1");
   test_ntop6_reduces("0:0:0:0:0:ffff:c0a8:0101", "::ffff:192.168.1.1");