ArgsTests.Data.DataSourceTests.LoadMoreBasic C# (CSharp) Method

        public void LoadMoreBasic()
        {
            int expectedNumberOfItems = 95;
            CliMessagePump pump = new CliMessagePump(ConsoleProvider.Current);
            TestLoadMoreDataSource dataSource = new TestLoadMoreDataSource(pump, expectedNumberOfItems, TimeSpan.FromMilliseconds(50));

            var query = new CollectionQuery(0, 7, null);
            List<object> viewedData = new List<object>();
            var pumpTask = pump.Start();
            try
            {
                // make sure the pump has started up
                Thread.Sleep(20);

                // the first call to GetDataView should return an empty result that indicates that the view is incomplete
                // because it is still loading data
                var initialDataView = dataSource.GetDataView(query);
                Assert.IsFalse(initialDataView.IsViewComplete);
                Assert.IsFalse(initialDataView.IsViewEndOfData);
                Assert.AreEqual(0, initialDataView.Items.Count);

                // Since we're simulating the server call and we know the max amount of time it can take wait twice that long
                Thread.Sleep(dataSource.MaxDelay + dataSource.MaxDelay);

                // Now there should be a full page of data available to us
                var nextAttemptDataView = dataSource.GetDataView(query);
                Assert.AreEqual(query.Take, nextAttemptDataView.Items.Count);
                Assert.IsTrue(nextAttemptDataView.IsViewComplete);
                Assert.IsFalse(nextAttemptDataView.IsViewEndOfData);

                viewedData.AddRange(nextAttemptDataView.Items);
                query.Skip += query.Take;

                // now ask for data in a tight loop.  Sometimes we will get more data, sometimes we'll get an empty page
                // while more data is being loaded
                while (nextAttemptDataView.IsViewEndOfData == false)
                {
                    nextAttemptDataView = dataSource.GetDataView(query);

                    Console.WriteLine(nextAttemptDataView.Items.Count + " items, viewComplete == " + nextAttemptDataView.IsViewComplete);

                    if (nextAttemptDataView.Items.Count < query.Take && nextAttemptDataView.IsViewEndOfData == false)
                    {
                        Thread.Sleep(10);
                        Assert.IsFalse(nextAttemptDataView.IsViewComplete);
                    }
                    else if (nextAttemptDataView.Items.Count == query.Take)
                    {
                        Assert.IsTrue(nextAttemptDataView.IsViewComplete);
                    }
                    else if (nextAttemptDataView.Items.Count > query.Take)
                    {
                        Assert.Fail(nextAttemptDataView.Items.Count + " should never exceed " + query.Take);
                    }

                    viewedData.AddRange(nextAttemptDataView.Items);
                    query.Skip += nextAttemptDataView.Items.Count;
                }

                int nextExpectedId = 0;
                foreach (var item in viewedData)
                {
                    Assert.IsNotNull(item);
                    Console.WriteLine(item);
                    Assert.AreEqual(nextExpectedId++, ((Item)item).Id);
                }

                Assert.AreEqual(expectedNumberOfItems, viewedData.Count);
                console.Input.Enqueue(new ConsoleKeyInfo(' ', ConsoleKey.Escape, false, false, false));
            } finally
            {
                pump.Stop();
                pumpTask.Wait();
            }
        }