From 5341563668df96f0d4e1d9d1fdd9761a55a57d76 Mon Sep 17 00:00:00 2001
From: Sasha Koshka <sashakoshka@tebibyte.media>
Date: Wed, 19 Nov 2025 14:42:29 -0500
Subject: [PATCH] Test that METADAPT-A can tx/rx different messages
 consecutively

---
 metadapta_test.go | 148 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 148 insertions(+)

diff --git a/metadapta_test.go b/metadapta_test.go
index f4f48aa..7bffe08 100644
--- a/metadapta_test.go
+++ b/metadapta_test.go
@@ -1,11 +1,14 @@
 package hopp
 
 import "io"
+import "net"
+import "sync"
 import "bytes"
 import "errors"
 import "slices"
 import "testing"
 import "context"
+import tu "git.tebibyte.media/sashakoshka/hopp/internal/testutil"
 
 // some of these tests spawn goroutines that can signal a failure.
 // abide by the documentation for testing.T (https://pkg.go.dev/testing#T):
@@ -271,6 +274,151 @@ func TestEncodeDecodeMessageA(test *testing.T) {
 	}
 }
 
+func TestConsecutiveWrite(test *testing.T) {
+	packets := [][]byte {
+		[]byte {
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
+			0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05,
+			0x43, 0x00, 0x00, 0x00, 0x07 },
+		
+		[]byte {
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
+			0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05,
+			0x43, 0x00, 0x00, 0x00, 0x08 },
+	}
+	payloads := [][]byte {
+		[]byte { 0x43, 0x00, 0x00, 0x00, 0x07 },
+		[]byte { 0x43, 0x00, 0x00, 0x00, 0x08 },
+	}
+
+	var group sync.WaitGroup
+	group.Add(2)
+
+	// server
+	listener, err := net.Listen("tcp", "localhost:9999")
+	if err != nil { test.Fatal("SERVER", err) }
+	go func() {
+		defer group.Done()
+		defer listener.Close()
+		conn, err := listener.Accept()
+		if err != nil { test.Fatal("SERVER", err) }
+		defer conn.Close()
+		
+		buf := [16]byte { }
+		for {
+			_, err := conn.Read(buf[:])
+			if err != nil { break }
+		}
+	}()
+
+	// client
+	go func() {
+		defer group.Done()
+		conn, err := net.Dial("tcp", "localhost:9999")
+		if err != nil { test.Fatal("CLIENT", err) }
+		defer conn.Close()
+		recorder := tu.RecordConn(conn)
+
+		a := AdaptA(recorder, ClientSide)
+		trans, err := a.OpenTrans()
+		if err != nil { test.Fatal("CLIENT", err) }
+
+		for _, payload := range payloads {
+			err := trans.Send(0x0000, payload)
+			if err != nil { test.Fatal("CLIENT", err) }
+		}
+
+		test.Log("CLIENT recorded output:\n" + recorder.Dump())
+		if len(recorder.Log) != 2 { test.Fatal("wrong length") }
+		if !slices.Equal(recorder.Log[0].([]byte), packets[0]) {
+			test.Fatal("not equal")
+		}
+		if !slices.Equal(recorder.Log[1].([]byte), packets[1]) {
+			test.Fatal("not equal")
+		}
+	}()
+
+	group.Wait()
+}
+
+func TestConsecutiveRead(test *testing.T) {
+	stream := []byte {
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
+		0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05,
+		0x43, 0x00, 0x00, 0x00, 0x07,
+
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
+		0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05,
+		0x43, 0x00, 0x00, 0x00, 0x08,
+	}
+	payloads := [][]byte {
+		[]byte { 0x43, 0x00, 0x00, 0x00, 0x07 },
+		[]byte { 0x43, 0x00, 0x00, 0x00, 0x08 },
+	}
+
+	var group sync.WaitGroup
+	group.Add(2)
+
+	// server
+	listener, err := net.Listen("tcp", "localhost:9999")
+	if err != nil { test.Fatal("SERVER", err) }
+	go func() {
+		defer group.Done()
+		defer listener.Close()
+		conn, err := listener.Accept()
+		if err != nil { test.Fatal("SERVER", err) }
+		defer conn.Close()
+		
+		a := AdaptA(conn, ServerSide)
+		trans, err := a.AcceptTrans()
+		if err != nil { test.Fatal("SERVER", err) }
+		index := 0
+		for {
+			method, data, err := trans.Receive()
+			if err != nil {
+				if !errors.Is(err, io.EOF) {
+					test.Fatal("SERVER", err)
+				}
+				break
+			}
+			test.Logf("SERVER GOT: M%04X %s", method, tu.HexBytes(data))
+			if index >= len(payloads) {
+				test.Fatalf(
+					"SERVER we weren't supposed to receive %d messages",
+					index + 1)
+			}
+			if method != 0 {
+				test.Fatal("SERVER", "method not equal")
+			}
+			if !slices.Equal(data, payloads[index]) {
+				test.Fatal("SERVER", "data not equal")
+			}
+			index ++
+		}
+		if index != len(payloads) {
+			test.Fatalf(
+				"SERVER we weren't supposed to receive %d messages",
+				index + 1)
+		}
+	}()
+
+	// client
+	go func() {
+		defer group.Done()
+		conn, err := net.Dial("tcp", "localhost:9999")
+		if err != nil { test.Fatal("CLIENT", err) }
+		defer conn.Close()
+		_, err = conn.Write(stream)
+		if err != nil { test.Fatal("CLIENT", err) }
+	}()
+
+	group.Wait()
+}
+
 func clientServerEnvironment(test *testing.T, clientFunc func(conn Conn), serverFunc func(conn Conn)) {
 	network := "tcp"
 	addr := "localhost:7959"