public void CreateArticleAndAddItToDb_WhenParametersAreCorrect()
        {
            // Arrange
            var            dbContextMock = new Mock <ApplicationDbContext>();
            List <Article> articles      = new List <Article>();

            string articlieAuthor = "author";
            string articleTitle   = "title";
            string articleContent = "content";

            var articlesSetMock = new Mock <DbSet <Article> >().SetupData(articles);


            dbContextMock.SetupGet(m => m.Articles).Returns(articlesSetMock.Object);

            ArticleServices service = new ArticleServices(dbContextMock.Object);

            // Act
            service.AddArticle(articlieAuthor, articleTitle, articleContent);

            // Assert
            var article = dbContextMock.Object.Articles.Single();

            Assert.AreEqual(articleTitle, article.Title);
            Assert.AreEqual(articleContent, article.Content);
            Assert.AreEqual(articlieAuthor, article.Author);

            dbContextMock.Verify(m => m.SaveChanges(), Times.Once());
        }