From 48046dc9c5cc79897d283c7fc2fad8934dc106c6 Mon Sep 17 00:00:00 2001
From: Kristoffer Dalby <kristoffer@dalby.cc>
Date: Wed, 7 Oct 2026 09:34:52 +0000
Subject: [PATCH] mapper: allow unchanged self in the full-update ping test

Updates #3518
---
 hscontrol/mapper/batcher_test.go | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/hscontrol/mapper/batcher_test.go b/hscontrol/mapper/batcher_test.go
index 75c417ec5..db343333b 100644
--- a/hscontrol/mapper/batcher_test.go
+++ b/hscontrol/mapper/batcher_test.go
@@ -1218,7 +1218,9 @@ func TestBatcherPingSurvivesFullUpdate(t *testing.T) {
 			}
 
 			isFull := func(r *tailcfg.MapResponse) bool {
-				return r.Node != nil && r.DERPMap != nil && len(r.Peers) > 0
+				// An unchanged self may be omitted for this connection, while
+				// the full peer list and DERP map still distinguish the full.
+				return r.DERPMap != nil && len(r.Peers) > 0
 			}
 
 			frames := collect(target.ch)