Ready for big test.

pymodbus/transport/stub.py

@@ -1,18 +1,30 @@
 """ModbusProtocol network stub."""
 from __future__ import annotations
 
-from pymodbus.transport.transport import ModbusProtocol
+from pymodbus.transport.transport import CommParams, ModbusProtocol
 
 
 class ModbusProtocolStub(ModbusProtocol):
     """Protocol layer including transport."""
 
+    def __init__(
+        self,
+        params: CommParams,
+        is_server: bool,
+        handler: callable | None = None,
+    ) -> None:
+        """Initialize a stub instance."""
+        self.stub_handle_data = handler if handler else self.dummy_handler
+        super().__init__(params, is_server)
+
+
     async def start_run(self):
         """Call need functions to start server/client."""
         if  self.is_server:
             return await self.transport_listen()
         return await self.transport_connect()
 
+
     def callback_data(self, data: bytes, addr: tuple | None = None) -> int:
         """Handle received data."""
         if (response := self.stub_handle_data(data)):
@@ -21,11 +33,13 @@ def callback_data(self, data: bytes, addr: tuple | None = None) -> int:
 
     def callback_new_connection(self) -> ModbusProtocol:
         """Call when listener receive new connection request."""
-        return ModbusProtocolStub(self.comm_params, False)
+        new_stub = ModbusProtocolStub(self.comm_params, False)
+        new_stub.stub_handle_data = self.stub_handle_data
+        return new_stub
 
     # ---------------- #
     # external methods #
     # ---------------- #
-    def stub_handle_data(self, data: bytes) -> bytes | None:
+    def dummy_handler(self, data: bytes) -> bytes | None:
         """Handle received data."""
         return data

test/test_network.py

@@ -30,12 +30,24 @@ async def test_stub(self, use_port, use_cls):
 
     async def test_double_packet(self, use_port, use_cls):
         """Test double packet on network."""
-        Log.debug("test_double_packet {}", use_port)
-        client = AsyncModbusTcpClient(NULLMODEM_HOST, port=use_port)
-        stub = ModbusProtocolStub(use_cls, True)
+        old_data = b''
+
+        def local_handle_data(data: bytes) -> bytes | None:
+            """Handle server side for this test case."""
+            nonlocal old_data
+
+            addr = int(data[9])
+            if addr == 1:
+                return None
+            return data
+
+        stub = ModbusProtocolStub(use_cls, True, handler=local_handle_data)
+        stub.stub_handle_data = local_handle_data
         await stub.start_run()
+
+        client = AsyncModbusTcpClient(NULLMODEM_HOST, port=use_port)
         assert await client.connect()
-        # await client.read_holding_registers(address=1, count=2)
+        await client.read_holding_registers(address=10, count=2)
         # await asyncio.gather(*[client.read_holding_registers(address=x, count=2) for x in range(0, 1000, 100)])
         client.transport_close()
         stub.transport_close()