@Test
void event_with_no_routes_should_be_consumed_as_an_empty_routing_plan() {

    final long vehicleId = 12;
    final Vehicle vehicle = VehicleFactory.testVehicle(vehicleId);
    when(vehicleRepository.find(vehicleId)).thenReturn(Optional.of(vehicle));
    RouteChangedEvent event = new RouteChangedEvent(
            this,
            Distance.ZERO,
            singletonList(vehicleId),
            null,
            emptyList(),
            emptyList());
    routeListener.onApplicationEvent(event);
    verifyNoInteractions(router);
    RoutingPlan routingPlan = verifyAndCaptureConsumedPlan();
    assertThat(routingPlan.vehicles()).containsExactly(vehicle);
    assertThat(routingPlan.depot()).isEmpty();
    assertThat(routingPlan.visits()).isEmpty();
    assertThat(routingPlan.routes()).isEmpty();
}