feat: add system.io.pipeline support to pipe io

src/process.tests/PipingTests.cs

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: EUPL-1.2
 
 using System.Text;
+using System.IO.Pipelines;
 
 using Geekeey.Process.Buffered;
 
@@ -64,6 +65,23 @@ internal sealed class PipingTests
 		await Assert.That(result.StandardOutput.Trim()).IsEqualTo("Hello World!");
 	}
 
+	[Test]
+	public async Task I_can_execute_a_command_and_pipe_the_stdin_from_a_pipe_reader()
+	{
+		var pipe = new Pipe();
+		await pipe.Writer.WriteAsync("Hello World!"u8.ToArray());
+		await pipe.Writer.CompleteAsync();
+
+		var cmd = PipeSource.FromPipeReader(pipe.Reader) |
+				  new Command(Testing.Fixture.Program.FilePath)
+					  .WithArguments("echo-stdin");
+
+		var result = await cmd.ExecuteBufferedAsync();
+
+		await Assert.That(result.StandardOutput.Trim()).IsEqualTo("Hello World!");
+		await pipe.Reader.CompleteAsync();
+	}
+
 	[Test]
 	public async Task I_can_execute_a_command_and_pipe_the_stdin_from_a_stream_with_a_custom_buffer_size()
 	{
@@ -570,6 +588,37 @@ internal sealed class PipingTests
 		}
 	}
 
+	[Test]
+	public async Task I_can_execute_a_command_and_pipe_the_stdout_to_a_pipe_writer()
+	{
+		// Arrange
+		var pipe = new Pipe();
+		var cmd = new Command(Testing.Fixture.Program.FilePath)
+				  .WithArguments(["generate", "blob", "--length", "100000"]) |
+			  PipeTarget.ToPipeWriter(pipe.Writer);
+
+		// Act
+		using var output = new MemoryStream();
+		var executionTask = cmd.ExecuteAsync();
+		while (true)
+		{
+			var result = await pipe.Reader.ReadAsync();
+			foreach (var segment in result.Buffer)
+			{
+				await output.WriteAsync(segment);
+			}
+			pipe.Reader.AdvanceTo(result.Buffer.End);
+			if (result.IsCompleted)
+			{
+				break;
+			}
+		}
+		await executionTask;
+		await pipe.Reader.CompleteAsync();
+
+		await Assert.That(output.Length).IsEqualTo(100_000);
+	}
+
 	[Test]
 	public async Task I_can_execute_a_command_and_pipe_the_stdout_into_multiple_hierarchical_targets()
 	{