public async Task DeletePostShouldWorkCorrectly() { var posts = new List <Post>(); var mockPostRepo = new Mock <IDeletableEntityRepository <Post> >(); mockPostRepo.Setup(x => x.All()).Returns(posts.AsQueryable()); mockPostRepo.Setup(x => x.AddAsync(It.IsAny <Post>())).Callback((Post ps) => posts.Add(ps)); var service = new AdminsService(mockPostRepo.Object, null, null, null, null); var postToDelete = new Post { Id = "123", }; posts.Add(postToDelete); await service.DeletePost("123"); Assert.Equal(true, postToDelete.IsDeleted); }