Add an uncaught exception handler.

qt_ui/uncaughtexceptionhandler.py

@@ -0,0 +1,42 @@
+# From https://timlehr.com/python-exception-hooks-with-qt-message-box/
+import logging
+import sys
+import traceback
+
+from PySide2.QtCore import Signal, QObject
+from PySide2.QtWidgets import QMessageBox, QApplication
+
+
+class UncaughtExceptionHandler(QObject):
+    _exception_caught = Signal(str, str)
+
+    def __init__(self, parent: QObject):
+        super().__init__(parent)
+        sys.excepthook = self.exception_hook
+        # Use a signal so that the message box always comes from the main thread.
+        self._exception_caught.connect(self.show_exception_box)
+
+    def exception_hook(self, exc_type, exc_value, exc_traceback):
+        if issubclass(exc_type, KeyboardInterrupt):
+            # Ignore keyboard interrupt to support console applications.
+            sys.__excepthook__(exc_type, exc_value, exc_traceback)
+            return
+
+        logging.exception(
+            "Uncaught exception", exc_info=(exc_type, exc_value, exc_traceback)
+        )
+        self._exception_caught.emit(
+            str(exc_value),
+            "".join(traceback.format_exception(exc_type, exc_value, exc_traceback)),
+        )
+
+    def show_exception_box(self, message: str, exception: str) -> None:
+        if QApplication.instance() is not None:
+            QMessageBox().critical(
+                self.parent(),
+                "An unexpected error occurred",
+                "\n".join([message, "", exception]),
+                QMessageBox.Ok,
+            )
+        else:
+            logging.critical("No QApplication instance available.")

qt_ui/windows/QLiberationWindow.py

@@ -24,6 +24,7 @@ from qt_ui import liberation_install
 from qt_ui.dialogs import Dialog
 from qt_ui.models import GameModel
 from qt_ui.uiconstants import URLS
+from qt_ui.uncaughtexceptionhandler import UncaughtExceptionHandler
 from qt_ui.widgets.QTopPanel import QTopPanel
 from qt_ui.widgets.ato import QAirTaskingOrderPanel
 from qt_ui.widgets.map.QLiberationMap import QLiberationMap
@@ -42,7 +43,9 @@ from qt_ui.windows.logs.QLogsWindow import QLogsWindow
 
 class QLiberationWindow(QMainWindow):
     def __init__(self, game: Optional[Game]) -> None:
-        super(QLiberationWindow, self).__init__()
+        super().__init__()
+
+        self._uncaught_exception_handler = UncaughtExceptionHandler(self)
 
         self.game = game
         self.game_model = GameModel(game)