public async Task GetCommentsByMusicIDShouldReturnCorrectComments()
        {
            var comments = new List <Comments>
            {
                new Comments()
                {
                    Id = 1, UploadMusicId = 10
                },
                new Comments()
                {
                    Id = 3, UploadMusicId = 10
                }
            };

            databaseMock.Setup(db => db.GetCommentsByMusicIDAsync(It.IsAny <int>())).Returns(Task.FromResult <List <Comments> >(comments));
            var newMusicBL = new UploadedMusicBL(databaseMock.Object);

            var result = await newMusicBL.GetCommentsByMusicIDAsync(10);

            Assert.NotNull(result);
            Assert.Equal(2, result.Count());
            Assert.Equal(10, result.FirstOrDefault().UploadMusicId);
            databaseMock.Verify(db => db.GetCommentsByMusicIDAsync(It.IsAny <int>()));
        }