I am developing an API for a real-time multiplayer game and aim to create integration tests for my STOMP API. While using mocks in integration tests is unconventional, I want to verify that the correct endpoints and methods are accessed during specific events.

@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
@TestPropertySource(properties = {"spring.main.allow-bean-definition-overriding=true"})
public class PublishToServerTest {

    @LocalServerPort
    private int port;

    @MockBean
    private SimpMessagingTemplate messagingTemplate;

    @MockBean
    private LobbyService lobbyService;

    @Test
    public void testPublishPlayerToLobby() throws InterruptedException {
        var timeout = 3; // Seconds
        var webSocketClient = new StandardWebSocketClient();
        var stompClient = new WebSocketStompClient(webSocketClient);
        stompClient.setMessageConverter(new MappingJackson2MessageConverter());
        stompClient.setTaskScheduler(new DefaultManagedTaskScheduler());

        var sessionHandler = new ExtendedStompSessionHandler() {
            @Override
            public void afterConnected(StompSession session, @NonNull StompHeaders connectedHeaders) {
                var clientPayload = new IncomingPlayerClientPayload("0", 0);
                session.send("/game/seek-opponent", clientPayload);

                verify(lobbyService).matchPlayer(any());
                getLatch().countDown();
            }

            @Override
            public void handleException(@NonNull StompSession session, StompCommand command, @NonNull StompHeaders headers, @NonNull byte[] payload, @NonNull Throwable exception) {
                fail(exception.getMessage());
            }
        };
        stompClient.connectAsync(String.format("ws://localhost:%d/ws", port), sessionHandler);

        var messageSent = sessionHandler.getLatch().await(timeout, TimeUnit.SECONDS);
        assertTrue(messageSent);
    }

LobbyService is responsible for creating new records in my Firestore database. As expected, when I mock this service, no database interactions occur during the test, and I will be able to confirm that the correct method is accessed. However, the verify(lobbyService).matchPlayer(any()) call fails, saying that the method interaction is not being detected by Mockito.

Wanted but not invoked:
lobbyService bean.matchPlayer(<any>);