diff --git a/machine_test.go b/machine_test.go
index bd91176..f3c5637 100644
--- a/machine_test.go
+++ b/machine_test.go
@@ -57,7 +57,7 @@ func TestMachineAddSubscription(t *testing.T) {
 	s.AddTransition("connect", "disconnected", "start_connection")
 	assert.Nil(t, s.AddSubscription("connect", x))
 	s.AddModel(setupModel("disconnected"))
-	s.Trigger("connect")
+	assert.Nil(t, s.Trigger("connect"))
 	exitMessage := <-*x.(*EventChannel)
 	enterMessage := <-*x.(*EventChannel)
 	if exitMessage.on == EXITSTATEEVENT && exitMessage.source == "disconnected" {