Add error handling for autosave session

qutebrowser/app.py

@@ -723,7 +723,11 @@ class Quitter:
         # Now we can hopefully quit without segfaults
         log.destroy.debug("Deferring QApplication::exit...")
         objreg.get('signal-handler').deactivate()
+        try:
             objreg.get('session-manager').delete('_autosave')
+        except sessions.SessionError as e:
+            log.sessions.error("Failed to delete autosave session: {}"
+                               .format(e))
         # We use a singleshot timer to exit here to minimize the likelihood of
         # segfaults.
         QTimer.singleShot(0, functools.partial(qApp.exit, status))

qutebrowser/browser/browsertab.py

@@ -28,7 +28,7 @@ from PyQt5.QtWidgets import QWidget, QApplication
 from qutebrowser.keyinput import modeman
 from qutebrowser.config import config
 from qutebrowser.utils import utils, objreg, usertypes, log, qtutils
-from qutebrowser.misc import miscwidgets, objects
+from qutebrowser.misc import miscwidgets, objects, sessions
 from qutebrowser.browser import mouse, hints
 
 
@@ -685,13 +685,16 @@ class AbstractTab(QWidget):
     @pyqtSlot(bool)
     def _on_load_finished(self, ok):
         sess_manager = objreg.get('session-manager')
+        try:
             sess_manager.save('_autosave')
+        except sessions.SessionError as e:
+            log.sessions.error("Failed to save autosave session: {}".format(e))
+
         if ok and not self._has_ssl_errors:
             if self.url().scheme() == 'https':
                 self._set_load_status(usertypes.LoadStatus.success_https)
             else:
                 self._set_load_status(usertypes.LoadStatus.success)
-
         elif ok:
             self._set_load_status(usertypes.LoadStatus.warn)
         else:

qutebrowser/misc/sessions.py

@@ -34,7 +34,6 @@ except ImportError:  # pragma: no cover
 from qutebrowser.utils import (standarddir, objreg, qtutils, log, usertypes,
                                message, utils)
 from qutebrowser.commands import cmdexc, cmdutils
-from qutebrowser.mainwindow import mainwindow
 from qutebrowser.config import config
 
 
@@ -346,6 +345,7 @@ class SessionManager(QObject):
             name: The name of the session to load.
             temp: If given, don't set the current session.
         """
+        from qutebrowser.mainwindow import mainwindow
         path = self._get_session_path(name, check_exists=True)
         try:
             with open(path, encoding='utf-8') as f: