The checks running are readable through reads and carry when each started (issue 1155)

internal/broker/controller_buckets_test.go

@@ -135,6 +135,12 @@ func TestTheMirrorsListAndTheWritersTableAgree(t *testing.T) {
 	for _, m := range ControllerMirrors() {
 		bucket := BucketName(ControllerSeat, m)
 		listed[bucket] = true
+		if why, other := MirrorsWrittenByAnother[m]; other { // 1155/AC3: the exception, with its reason
+			if why == "" {
+				t.Errorf("the mirror %s is written by another and says no reason", bucket)
+			}
+			continue
+		}
 		if !rowed[bucket] {
 			t.Errorf("the mirror %s is listed and no row of the writers table writes it", bucket)
 		}