Added extra Batch-Join test.

Open.ChannelExtensions.Tests/BatchTests.cs

@@ -1,4 +1,6 @@
 using System.Runtime.CompilerServices;
+using System.Threading.Channels;
+using System.Threading;
 
 namespace Open.ChannelExtensions.Tests;
 
@@ -407,4 +409,68 @@ public static async IAsyncEnumerable<IList<T>> ReadBatchEnumerableAsyncBakedIn<T
 			if (item?.Count > 0) yield return item;
 		}
 	}
+
+	[Fact]
+	public static async Task AnotherComplexBatchJoinScenario()
+	{
+		const int SIZE = 300000;
+		const long HTTP_BATCH_TIMEOUT = 10000;
+		const int MAX_PARALLELISM_HTTP = 8;
+		const int MAX_CACHE_WRITE_PARALLELISM = 8;
+
+		using var cts = new CancellationTokenSource(30_000);
+		var cancellationToken = cts.Token;
+		var channel = Channel.CreateBounded<int>(new BoundedChannelOptions(20) { SingleReader = false, SingleWriter = true });
+
+		int remaining = SIZE;
+		_ = Task.Run(async () =>
+		{
+			int n = 50;
+
+			while(remaining > 0)
+			{
+				await Task.Delay(20);
+				for (int i = 0; remaining > 0 && i < n; i++)
+				{
+					await channel.Writer.WriteAsync(remaining, cancellationToken);
+					remaining--;
+				}
+
+				n += 15;
+			}
+
+			await Task.Delay(30);
+			channel.Writer.Complete();
+		});
+
+		int count = 0;
+		var total = await channel.Reader
+			.Batch(100)
+			.WithTimeout(HTTP_BATCH_TIMEOUT)
+			.PipeAsync(
+				MAX_PARALLELISM_HTTP,
+				async x =>
+				{
+					await Task.Delay(50);
+					return x.ConvertAll(x => x * 2);
+				},
+				cancellationToken: cancellationToken
+			)
+			.Join()
+			.Batch(10)
+			.WithTimeout(HTTP_BATCH_TIMEOUT)
+			.ReadAllConcurrently(
+				MAX_CACHE_WRITE_PARALLELISM,
+				x =>
+				{
+					Debug.WriteLine("Value: {0}", string.Join(' ', x));
+					for (int i = 0; i < x.Count; i++)
+						Interlocked.Increment(ref count);
+				},
+				cancellationToken);
+
+		remaining.Should().Be(0);
+		channel.Reader.TryRead(out _).Should().BeFalse();
+		count.Should().Be(SIZE);
+	}
 }