public void GetAllGenreNames_ShouldReturnAllGenresWhenNoParameters() { // Arrange _genreRepository.Setup(g => g.GetMany(0, int.MaxValue, null, null, It.IsAny <SortDirection>(), It.IsAny <Expression <Func <Genre, object> >[]>())).Returns(_genres); // Act var result = _genreService.GetAllGenreNames(); // Assert Assert.Equal(result.Count(), _genres.Count()); }