Clean up Qt crash handlers before shutdown

graphlink_app/graphlink_app.py

@@ -6,7 +6,12 @@
 import graphlink_licensing
 from graphlink_config import apply_theme, set_current_model, sync_ollama_task_models
 from graphlink_logging import configure_logging
-from graphlink_crash import install_crash_handlers, mark_running, previous_run_crashed
+from graphlink_crash import (
+    install_crash_handlers,
+    mark_running,
+    previous_run_crashed,
+    uninstall_crash_handlers,
+)
 from graphlink_version import APP_VERSION
 
 def main():
@@ -19,6 +24,8 @@ def main():
 
     app = QApplication(sys.argv)
     app.setQuitOnLastWindowClosed(True)
+    # Remove Python/Qt crash callbacks before Qt destroys its Python wrappers.
+    app.aboutToQuit.connect(uninstall_crash_handlers)
 
     # Use the new SettingsManager (formerly LicenseManager)
     settings_manager = graphlink_licensing.SettingsManager()

graphlink_app/graphlink_crash.py

@@ -185,6 +185,43 @@ def install_crash_handlers(version="unknown", crash_dir=None):
         pass
 
 
+def uninstall_crash_handlers():
+    """Restore process-global handlers before Qt/PySide is torn down.
+
+    Crash reporting is installed before ``QApplication`` exists, so the normal
+    application shutdown path must explicitly remove the Qt message callback
+    while Qt's Python wrappers are still alive.  This is also required by the
+    test suite: leaving a callback that closes over PySide objects installed
+    until interpreter shutdown can turn an otherwise passing Qt test run into
+    a non-zero process exit.
+    """
+    global _installed, _faulthandler_file
+
+    sys.excepthook = sys.__excepthook__
+    threading.excepthook = threading.__excepthook__
+
+    try:
+        from PySide6.QtCore import qInstallMessageHandler
+
+        qInstallMessageHandler(None)
+    except (ImportError, AttributeError, RuntimeError, SystemError, TypeError):
+        pass
+
+    try:
+        faulthandler.disable()
+    except (AttributeError, RuntimeError, SystemError, ValueError):
+        pass
+
+    if _faulthandler_file is not None:
+        try:
+            _faulthandler_file.close()
+        except (AttributeError, OSError, ValueError):
+            pass
+        _faulthandler_file = None
+
+    _installed = False
+
+
 # --- "did the previous run crash" sentinel ---
 #
 # A JSON file at ~/.graphlink/running.lock is written at startup (mark_running) and

graphlink_app/tests/test_crash_reporting.py

@@ -164,15 +164,7 @@ def test_url_targets_the_repo_and_embeds_the_report(self):
 
 class TestInstallCrashHandlers:
     def teardown_method(self):
-        sys.excepthook = sys.__excepthook__
-        threading.excepthook = threading.__excepthook__
-        graphlink_crash._installed = False
-        if graphlink_crash._faulthandler_file is not None:
-            try:
-                graphlink_crash._faulthandler_file.close()
-            except Exception:
-                pass
-            graphlink_crash._faulthandler_file = None
+        graphlink_crash.uninstall_crash_handlers()
 
     def test_installs_a_non_default_excepthook(self, tmp_path):
         graphlink_crash.install_crash_handlers(version="v1", crash_dir=tmp_path)
@@ -187,6 +179,16 @@ def test_is_idempotent(self, tmp_path):
 
         assert sys.excepthook is first_hook
 
+    def test_uninstall_restores_process_global_handlers(self, tmp_path):
+        graphlink_crash.install_crash_handlers(version="v1", crash_dir=tmp_path)
+
+        graphlink_crash.uninstall_crash_handlers()
+
+        assert sys.excepthook is sys.__excepthook__
+        assert threading.excepthook is threading.__excepthook__
+        assert graphlink_crash._installed is False
+        assert graphlink_crash._faulthandler_file is None
+
     def test_the_installed_excepthook_writes_a_report(self, tmp_path, monkeypatch):
         monkeypatch.setattr(graphlink_crash, "_crash_dir", lambda base_dir=None: tmp_path)
         graphlink_crash.install_crash_handlers(version="v1", crash_dir=tmp_path)