fix(device_inputs): on_device_update additional _destroyed safeguard

bec_widgets/widgets/control/device_input/device_combobox/device_combobox.py

@@ -9,7 +9,7 @@ from bec_lib.device import ComputedSignal, Device, Positioner, ReadoutPriority
 from bec_lib.device import Signal as BECSignal
 from bec_lib.logger import bec_logger
 from pydantic import Field, field_validator
-from qtpy.QtCore import QSize, QStringListModel, Signal, Slot
+from qtpy.QtCore import QSize, QStringListModel, Qt, Signal, Slot
 from qtpy.QtWidgets import QComboBox, QCompleter, QSizePolicy
 
 from bec_widgets.utils.bec_connector import ConnectionConfig
@@ -191,6 +191,13 @@ class DeviceComboBox(BECWidget, QComboBox):
         if self.config.autocomplete:
             self.autocomplete = True
 
+        self._callback_id = self.bec_dispatcher.client.callbacks.register(
+            EventType.DEVICE_UPDATE, self.on_device_update
+        )
+        self.device_config_update.connect(
+            self.update_devices_from_filters, Qt.ConnectionType.QueuedConnection
+        )
+
         if available_devices is not None:
             self.set_available_devices(available_devices)
 
@@ -216,10 +223,6 @@ class DeviceComboBox(BECWidget, QComboBox):
         else:
             self.setCurrentText("")
 
-        self._callback_id = self.bec_dispatcher.client.callbacks.register(
-            EventType.DEVICE_UPDATE, self.on_device_update
-        )
-        self.device_config_update.connect(self.update_devices_from_filters)
         self.currentTextChanged.connect(self.check_validity)
         self.check_validity(self.currentText())
 
@@ -255,6 +258,9 @@ class DeviceComboBox(BECWidget, QComboBox):
     @SafeSlot()
     def update_devices_from_filters(self):
         """Refresh the available device list from current device/readout/signal filters."""
+        if self._callback_id is None or getattr(self, "_destroyed", False):
+            return
+
         self.config.device_filter = [entry.value for entry in self.device_filter]
         self.config.readout_filter = [entry.value for entry in self.readout_filter]
         self.config.signal_class_filter = self.signal_class_filter
@@ -489,6 +495,8 @@ class DeviceComboBox(BECWidget, QComboBox):
             action: Device update action emitted by BEC.
             content: Device update payload. Currently unused.
         """
+        if self._callback_id is None or getattr(self, "_destroyed", False):
+            return
         if action in ["add", "remove", "reload"]:
             self.device_config_update.emit()
 
@@ -496,6 +504,7 @@ class DeviceComboBox(BECWidget, QComboBox):
         """Cleanup the widget."""
         if self._callback_id is not None:
             self.bec_dispatcher.client.callbacks.remove(self._callback_id)
+            self._callback_id = None
         super().cleanup()
 
     def get_current_device(self) -> object:

bec_widgets/widgets/control/device_input/signal_combobox/signal_combobox.py

@@ -77,6 +77,7 @@ class SignalComboBox(BECWidget, QComboBox):
 
     device_signal_changed = Signal(str)
     signal_reset = Signal()
+    device_config_update = Signal()
 
     def __init__(
         self,
@@ -138,7 +139,10 @@ class SignalComboBox(BECWidget, QComboBox):
             self.autocomplete = True
 
         self._device_update_register = self.bec_dispatcher.client.callbacks.register(
-            EventType.DEVICE_UPDATE, self.update_signals_from_filters
+            EventType.DEVICE_UPDATE, self.on_device_update
+        )
+        self.device_config_update.connect(
+            self.update_signals_from_filters, Qt.ConnectionType.QueuedConnection
         )
         self.currentTextChanged.connect(self.on_text_changed)
 
@@ -207,6 +211,9 @@ class SignalComboBox(BECWidget, QComboBox):
             content: Optional callback payload from BEC device updates. Currently unused.
             metadata: Optional callback metadata from BEC device updates. Currently unused.
         """
+        if self._device_update_register is None or getattr(self, "_destroyed", False):
+            return
+
         self.config.signal_filter = [kind.name for kind in self.signal_filter]
 
         if self._signal_class_filter:
@@ -247,6 +254,13 @@ class SignalComboBox(BECWidget, QComboBox):
             ),
         )
 
+    def on_device_update(self, action: str, content: dict) -> None:
+        """Refresh filters when BEC reports device configuration changes."""
+        if self._device_update_register is None or getattr(self, "_destroyed", False):
+            return
+        if action in ["add", "remove", "reload"]:
+            self.device_config_update.emit()
+
     @Property(str)
     def device(self) -> str:
         """Selected device."""
@@ -588,7 +602,9 @@ class SignalComboBox(BECWidget, QComboBox):
 
     def cleanup(self):
         """Cleanup the widget."""
-        self.bec_dispatcher.client.callbacks.remove(self._device_update_register)
+        if self._device_update_register is not None:
+            self.bec_dispatcher.client.callbacks.remove(self._device_update_register)
+            self._device_update_register = None
         super().cleanup()
 
     @staticmethod

tests/unit_tests/test_device_input_widgets.py

@@ -1,3 +1,5 @@
+from unittest import mock
+
 import pytest
 from bec_lib.device import ReadoutPriority
 
@@ -124,6 +126,19 @@ def test_device_input_combobox_disabled_invalid_has_neutral_border(device_input_
     assert "red" in device_input_combobox.styleSheet()
 
 
+def test_device_input_combobox_cleanup_unregisters_callback(qtbot, mocked_client):
+    with mock.patch.object(mocked_client.callbacks, "remove"):
+        widget = DeviceComboBox(client=mocked_client)
+        qtbot.addWidget(widget)
+        callback_id = widget._callback_id
+
+        widget.close()
+        widget.deleteLater()
+
+        mocked_client.callbacks.remove.assert_called_once_with(callback_id)
+        assert widget._callback_id is None
+
+
 def test_get_device_from_input_combobox_init(device_input_combobox):
     device_input_combobox.setCurrentIndex(0)
     device_text = device_input_combobox.currentText()

tests/unit_tests/test_device_signal_input.py

@@ -188,10 +188,12 @@ def test_linked_device_combobox_updates_signal_combobox_on_each_text_change(
 def test_device_signal_input_base_cleanup(qtbot, mocked_client):
     with mock.patch.object(mocked_client.callbacks, "remove"):
         widget = SignalComboBox(client=mocked_client)
+        callback_id = widget._device_update_register
         widget.close()
         widget.deleteLater()
 
-        mocked_client.callbacks.remove.assert_called_once_with(widget._device_update_register)
+        mocked_client.callbacks.remove.assert_called_once_with(callback_id)
+        assert widget._device_update_register is None
 
 
 def test_signal_combobox_get_signal_name_with_item_data(qtbot, device_signal_combobox):