Fix cleanup guards and scan state transitions

Introduce explicit cleanup flags and tighten cleanup logic to avoid races and double-run teardown. Add _cleanp_requested and _cleanup_completed, replace uses of the old _cleanup_done flag, and only mark cleanup completed when no scan/preview/probe worker is active. Also always transition the scan state to IDLE when cleaning up. Update the e2e test to wait for scans to finish earlier and reduce related timeouts to reflect the more deterministic teardown behavior.

Author: C-Achard

dlclivegui/gui/camera_config/camera_config_dialog.py

@@ -48,6 +48,9 @@ def __init__(
         self.setWindowTitle("Configure Cameras")
         self.setMinimumSize(960, 720)
 
+        self._cleanp_requested = False
+        self._cleanup_completed = False
+
         self._dlc_camera_id: str | None = None
         # self.dlc_camera_id: str | None = None
         # Actual/working camera settings
@@ -106,7 +109,7 @@ def dlc_camera_id(self, value: str | None) -> None:
     def showEvent(self, event):
         super().showEvent(event)
         # Reset cleanup guard so close cleanup runs for each session
-        self._cleanup_done = False
+        self._cleanup_completed = False
 
         # Rebuild the working copy from the latest “accepted” settings
         self._working_settings = self._multi_camera_settings.model_copy(deep=True)
@@ -192,9 +195,9 @@ def reject(self) -> None:
     def _on_close_cleanup(self) -> None:
         """Stop preview, cancel workers, and reset scan UI. Safe to call multiple times."""
         # Guard to avoid running twice if closeEvent + reject/accept both run
-        if getattr(self, "_cleanup_done", False):
+        if getattr(self, "_cleanup_completed", False):
             return
-        self._cleanup_done = True
+        self._cleanp_requested = True
 
         # Stop preview (loader + backend + timer)
         try:
@@ -256,6 +259,13 @@ def _on_close_cleanup(self) -> None:
         except Exception:
             pass
 
+        if (
+            not self._is_scan_running()
+            and not self._is_preview_live()
+            and not (self._probe_worker and self._probe_worker.isRunning())
+        ):
+            self._cleanup_completed = True
+
     # -------------------------------
     # UI setup
     # -------------------------------
@@ -637,9 +647,7 @@ def _on_scan_thread_finished(self) -> None:
             return
 
         self._cleanup_scan_worker()
-        # Only transition to IDLE for the worker that was actually active.
-        if self._scan_state not in (CameraScanState.DONE,):
-            self._set_scan_state(CameraScanState.IDLE)
+        self._set_scan_state(CameraScanState.IDLE)
 
     def _on_scan_result(self, cams: list) -> None:
         if self.sender() is not self._scan_worker:

tests/gui/camera_config/test_cam_dialog_e2e.py

@@ -120,6 +120,7 @@ def dialog(qtbot, patch_detect_cameras):
     d = CameraConfigDialog(None, s)
     qtbot.addWidget(d)
     d.show()
+    qtbot.waitUntil(lambda: not d._is_scan_running(), timeout=2000)
     qtbot.waitExposed(d)
 
     yield d
@@ -136,7 +137,7 @@ def dialog(qtbot, patch_detect_cameras):
         d.close()
 
     qtbot.waitUntil(lambda: d._preview.loader is None, timeout=2000)
-    qtbot.waitUntil(lambda: not d._is_scan_running(), timeout=5000)
+    qtbot.waitUntil(lambda: not d._is_scan_running(), timeout=2000)
     qtbot.wait(50)
     qtbot.waitUntil(lambda: d._preview.state == PreviewState.IDLE, timeout=2000)