public void ByCategoryReturnsAllPostsContainingCategory()
        {
            const string expectedTitle    = "Expected";
            var          expectedCategory = new Category {
                UrlName = "Expected Category"
            };
            var otherCategory = new Category {
                UrlName = "Other Category"
            };

            var session = WithSessionContainingPosts(
                new Post {
                Title = expectedTitle, Category = expectedCategory
            },
                new Post {
                Title = "Not Expected", Category = otherCategory
            },
                new Post {
                Title = "Not Expected"
            });

            var repository = new PostRepository(session);

            var result = repository.ByCategory(expectedCategory);

            Assert.That(result.All(p => p.Title == expectedTitle));
        }