public void JobPostShouldExist() { var repository = new Mock <IDeletableEntityRepository <JobPost> >(); repository.Setup(posts => posts.All()) .Returns(new List <JobPost> { new JobPost() { Id = 1, }, new JobPost() { Id = 2, }, new JobPost() { Id = 3, }, }.AsQueryable()); var service = new JobPostsService(repository.Object, null); Assert.True(service.JobPostExist(1)); repository.Verify(x => x.All(), Times.Once); }