[Tests] Catch and print errors in setup/teardown

deluge/tests/basetest.py

@@ -19,16 +19,26 @@ class BaseTestCase(unittest.TestCase):
             warnings.warn("The component._ComponentRegistry.components is not empty on test setup."
                           "This is probably caused by another test that didn't clean up after finishing!: %s" %
                           component._ComponentRegistry.components)
-        return self.set_up()
+        d = maybeDeferred(self.set_up)
+
+        def on_setup_error(error):
+            warnings.warn("Error caught in test setup!\n%s" % error.getTraceback())
+            self.fail()
+
+        return d.addErrback(on_setup_error)
 
     def tearDown(self):  # NOQA
         d = maybeDeferred(self.tear_down)
 
-        def on_teared_down(result):
+        def on_teardown_failed(error):
+            warnings.warn("Error caught in test teardown!\n%s" % error.getTraceback())
+            self.fail()
+
+        def on_teardown_complete(result):
             component._ComponentRegistry.components.clear()
             component._ComponentRegistry.dependents.clear()
 
-        return d.addCallback(on_teared_down)
+        return d.addCallbacks(on_teardown_complete, on_teardown_failed)
 
     def set_up(self):
         pass

deluge/ui/web/auth.py

@@ -82,8 +82,13 @@ class Auth(JSONComponent):
     def __init__(self):
         super(Auth, self).__init__("Auth")
         self.worker = LoopingCall(self._clean_sessions)
+
+    def start(self):
         self.worker.start(5)
 
+    def stop(self):
+        self.worker.stop()
+
     def _clean_sessions(self):
         config = component.get("DelugeWeb").config
         session_ids = config["sessions"].keys()