public void should_return_articles_from_last_page() { var articlesFromDb = new ArticleBuilder().Build(15).Map(); List <ArticleDb> filteredArticles = articlesFromDb.Skip(10).Take(5).ToList(); List <ArticleDb> mappedArticles = null; Action <object> mapArticles = (list) => { mappedArticles = list as List <ArticleDb>; }; _articlesRepository.Setup(n => n.Get(null, It.IsAny <Func <IQueryable <ArticleDb>, IOrderedQueryable <ArticleDb> > >(), "")) .Returns(articlesFromDb); _mapper.Setup(n => n.Map <List <Article> >(It.IsAny <List <ArticleDb> >())).Callback(mapArticles); _sut.Get(5, 3); mappedArticles.Should().BeEquivalentTo(filteredArticles); }