htlcswitch: add final htlc event to notifier

lntest/itest/lnd_multi-hop-error-propagation_test.go

@@ -424,4 +424,14 @@ func assertLinkFailure(t *harnessTest,
 		t.Fatalf("expected: %v, got: %v", failureDetail,
 			linkFail.LinkFailEvent.FailureDetail)
 	}
+
+	event = assertEventAndType(t, routerrpc.HtlcEvent_UNKNOWN, client)
+	finalHtlc, ok := event.Event.(*routerrpc.HtlcEvent_FinalHtlcEvent)
+	if !ok {
+		t.Fatalf("expected final htlc, got: %T", event.Event)
+	}
+
+	if finalHtlc.FinalHtlcEvent.Settled {
+		t.Fatalf("expected final fail")
+	}
 }

lntest/itest/lnd_multi-hop-payments_test.go

@@ -348,13 +348,26 @@ func assertHtlcEvents(t *harnessTest, fwdCount, fwdFailCount, settleCount int,
 	userType routerrpc.HtlcEvent_EventType,
 	client routerrpc.Router_SubscribeHtlcEventsClient) {
 
-	var forwards, forwardFails, settles int
+	var forwards, forwardFails, settles, finalSettles, finalFails int
+
+	var finalFailCount, finalSettleCount int
+	if userType != routerrpc.HtlcEvent_SEND {
+		finalFailCount = fwdFailCount
+		finalSettleCount = settleCount
+	}
+
+	numEvents := fwdCount + fwdFailCount + settleCount +
+		finalFailCount + finalSettleCount
 
-	numEvents := fwdCount + fwdFailCount + settleCount
 	for i := 0; i < numEvents; i++ {
-		event := assertEventAndType(t, userType, client)
+		event, err := client.Recv()
+		if err != nil {
+			t.Fatalf("could not get event")
+		}
 
-		switch event.Event.(type) {
+		expectedEventType := userType
+
+		switch e := event.Event.(type) {
 		case *routerrpc.HtlcEvent_ForwardEvent:
 			forwards++
 
@@ -364,9 +377,23 @@ func assertHtlcEvents(t *harnessTest, fwdCount, fwdFailCount, settleCount int,
 		case *routerrpc.HtlcEvent_SettleEvent:
 			settles++
 
+		case *routerrpc.HtlcEvent_FinalHtlcEvent:
+			if e.FinalHtlcEvent.Settled {
+				finalSettles++
+			} else {
+				finalFails++
+			}
+
+			expectedEventType = routerrpc.HtlcEvent_UNKNOWN
+
 		default:
 			t.Fatalf("unexpected event: %T", event.Event)
 		}
+
+		if event.EventType != expectedEventType {
+			t.Fatalf("expected: %v, got: %v", expectedEventType,
+				event.EventType)
+		}
 	}
 
 	if forwards != fwdCount {
@@ -378,9 +405,19 @@ func assertHtlcEvents(t *harnessTest, fwdCount, fwdFailCount, settleCount int,
 			forwardFails)
 	}
 
+	if finalFails != finalFailCount {
+		t.Fatalf("expected: %v final fails, got: %v", finalFailCount,
+			finalFails)
+	}
+
 	if settles != settleCount {
 		t.Fatalf("expected: %v settles, got: %v", settleCount, settles)
 	}
+
+	if finalSettles != finalSettleCount {
+		t.Fatalf("expected: %v settles, got: %v", finalSettleCount,
+			finalSettles)
+	}
 }
 
 // assertEventAndType reads an event from the stream provided and ensures that