public async Task SaveAsyncWhenSaveReturnsSaved()
        {
            //Arrange
            var     mockIllnessRepository    = GetDefaultIIllnessRepositoryInstance();
            var     mockPetIllnessRepository = GetDefaultIPetIllnessRepositoryInstance();
            var     mockUnitOfWork           = GetDefaultIUnitOfWorkInstance();
            Illness illness = new Illness {
                Id = 10, Name = "Diabetes"
            };

            mockIllnessRepository.Setup(r => r.AddAsync(illness))
            .Returns(Task.FromResult <Illness>(illness));

            var service = new IllnessService(mockUnitOfWork.Object, mockPetIllnessRepository.Object, mockIllnessRepository.Object);

            //Act
            IllnessResponse result = await service.SaveAsync(illness);

            //Assert
            result.Resource.Should().Be(illness);
        }
        public async Task GetByIdAsyncWhenNoCityFoundReturnsIllnesNotFoundResponse()
        {
            //Arrange
            var mockIllnessRepository    = GetDefaultIIllnessRepositoryInstance();
            var mockPetIllnessRepository = GetDefaultIPetIllnessRepositoryInstance();
            var mockUnitOfWork           = GetDefaultIUnitOfWorkInstance();
            var illnessId = 1;

            mockIllnessRepository.Setup(r => r.FindById(illnessId))
            .Returns(Task.FromResult <Illness>(null));

            var service = new IllnessService(mockUnitOfWork.Object, mockPetIllnessRepository.Object, mockIllnessRepository.Object);

            //Act
            IllnessResponse result = await service.GetByIdAsync(illnessId);

            var message = result.Message;

            //Assert
            message.Should().Be("Illness not found");
        }