public async Task GetAllAsyncWhenNoPublicationsReturnsEmptyCollection()
{
//Arrange
var mockPublicationRepository = GetDefaultIPublicationRepositoryInstance();
var mockUnitOfWork = GetDefaultIUnitOfWorkInstance();
var publicationId = 200;
mockPublicationRepository.Setup(r => r.FindById(publicationId))
.Returns(Task.FromResult <Publication>(null));
var service = new PublicationService(mockPublicationRepository.Object, mockUnitOfWork.Object);
//Act
PublicationResponse result = await service.GetByIdAsync(publicationId);
var message = result.Message;
//Assert
message.Should().Be("Publication not found");
}