public async Task Should_batch_async() { // Arrange var actualCollection = new List <Item>(); var expectedCollection = Enumerable.Range(0, 100).Select(x => new Item { Id = x }).ToList(); // TODO: Mock this collection to pass this unit test var query = expectedCollection.AsQueryable().OrderBy(x => x.Id); // Act await foreach (var items in _batchService.BatchAsync(query, 10)) { actualCollection.AddRange(items); } // Assert actualCollection.Should().BeEquivalentTo(expectedCollection); }