public async Task When_calling_get_async_and_devices_exists_it_should_invoke_devices_repository_get_async() { var deviceRepositoryMock = new Mock <IDeviceRepository>(); var mapperMock = new Mock <IMapper>(); var deviceService = new DeviceService(deviceRepositoryMock.Object, mapperMock.Object); await deviceService.BrowseAsync(); var devices = new HashSet <Device>() { new Device(Guid.NewGuid(), "ab1", new DateTime(), new DateTime(), new Shop(Guid.NewGuid(), "Toruń Kwiatowa 18/4", new Person("Łukasz", "Zieliński", "*****@*****.**", "530230655"), "001", "520640330")), new Device(Guid.NewGuid(), "ab2", new DateTime(), new DateTime(), new Shop(Guid.NewGuid(), "Toruń Kwiatowa 18/4", new Person("Łukasz", "Zieliński", "*****@*****.**", "530230655"), "001", "520640330")), new Device(Guid.NewGuid(), "ab3", new DateTime(), new DateTime(), new Shop(Guid.NewGuid(), "Toruń Kwiatowa 18/4", new Person("Łukasz", "Zieliński", "*****@*****.**", "530230655"), "001", "520640330")), }; deviceRepositoryMock.Setup(x => x.GetAllAsync()) .ReturnsAsync(devices); deviceRepositoryMock.Verify(x => x.GetAllAsync(), Times.Once()); }