Handle serial port close race condition in rfxtrx during shutdown

homeassistant/components/rfxtrx/__init__.py

@@ -127,6 +127,26 @@ def _create_rfx(
     else:
         transport = rfxtrxmod.PySerialTransport(config[CONF_DEVICE])
 
+        # Work around a race condition in pyRFXtrx during shutdown.
+        # When close_connection() closes the serial port, the background read
+        # thread may still be inside serial.read(), which calls
+        # os.read(self.fd, ...). Since closing sets fd=None, this raises
+        # TypeError. The library's transport_errors decorator only catches
+        # socket.error, SerialException, and OSError — not TypeError.
+        # https://github.com/Danielhiversen/pyRFXtrx/pull/155
+        original_receive = transport.receive_blocking
+
+        def _receive_blocking_wrapper() -> rfxtrxmod.RFXtrxEvent | None:
+            try:
+                return original_receive()
+            except TypeError:
+                if getattr(transport.serial, "fd", ...) is None:
+                    _LOGGER.debug("Serial port closed during read")
+                    return None
+                raise
+
+        transport.receive_blocking = _receive_blocking_wrapper
+
     rfx = rfxtrxmod.Connect(
         transport,
         event_callback,

tests/components/rfxtrx/test_init.py

@@ -2,8 +2,9 @@
 
 from __future__ import annotations
 
-from unittest.mock import ANY, call
+from unittest.mock import ANY, MagicMock, call
 
+import pytest
 import RFXtrx as rfxtrxmod
 
 from homeassistant.components.rfxtrx.const import EVENT_RFXTRX_EVENT
@@ -19,6 +20,47 @@ from tests.typing import WebSocketGenerator
 SOME_PROTOCOLS = ["ac", "arc"]
 
 
+async def test_serial_receive_blocking_type_error_on_shutdown(
+    hass: HomeAssistant, rfxtrx, transport_mock
+) -> None:
+    """Test that TypeError during serial shutdown is suppressed.
+
+    pyRFXtrx has a race condition where closing the serial port sets fd=None
+    while the read thread is still inside os.read(), causing a TypeError.
+    """
+    original_receive = MagicMock(
+        side_effect=TypeError("'NoneType' object cannot be interpreted as an integer")
+    )
+    serial_mock = MagicMock(fd=None)
+    transport_mock.return_value.receive_blocking = original_receive
+    transport_mock.return_value.serial = serial_mock
+
+    config_entry = await setup_rfx_test_cfg(hass, device="/dev/ttyUSBfake")
+    assert config_entry.state is ConfigEntryState.LOADED
+
+    # After setup, the transport's receive_blocking should have been wrapped.
+    # Calling the wrapper should suppress the TypeError when serial.fd is None.
+    wrapped_receive = transport_mock.return_value.receive_blocking
+    assert wrapped_receive() is None
+
+
+async def test_serial_receive_blocking_type_error_reraised(
+    hass: HomeAssistant, rfxtrx, transport_mock
+) -> None:
+    """Test that unrelated TypeErrors still propagate."""
+    original_receive = MagicMock(side_effect=TypeError("unexpected"))
+    serial_mock = MagicMock(fd=1)
+    transport_mock.return_value.receive_blocking = original_receive
+    transport_mock.return_value.serial = serial_mock
+
+    config_entry = await setup_rfx_test_cfg(hass, device="/dev/ttyUSBfake")
+    assert config_entry.state is ConfigEntryState.LOADED
+
+    wrapped_receive = transport_mock.return_value.receive_blocking
+    with pytest.raises(TypeError, match="unexpected"):
+        wrapped_receive()
+
+
 async def test_fire_event(
     hass: HomeAssistant, device_registry: dr.DeviceRegistry, rfxtrx
 ) -> None: