public void StopRadio_Should_Not_Throw_Exceptions() { // Arrange var miioDevice = new Mock <IMiioTransport>(); var miioGateway = new MiioGateway(miioDevice.Object); miioDevice.Setup(x => x.SendMessage(It.Is <string>(s => s.Contains("play_fm")))) .Returns("{\"result\":[\"ok\"],\"id\":1}"); // Act miioGateway.StopRadio(); // Assert var msg = "{\"id\": 1, \"method\": \"play_fm\", \"params\": [\"off\"]}"; miioDevice.Verify(x => x.SendMessage(msg), Times.Once()); }