task handler remove_all method created. task handler server restart unit test created.

Added method remove_all to task handler. (intended for unit testing)
Created a method to mimic a server restart for the purpose of task handler.

test_delay unit test passes.

evennia/scripts/taskhandler.py

@@ -341,6 +341,30 @@ class TaskHandler(object):
             del d
         return True
 
+    def remove_all(self, save=True, cancel=True):
+        """
+        Remove all tasks.
+        By default tasks are canceled and removed from the database also.
+
+        Arguments:
+            save=True (bool): Should changes to persistent tasks be saved to database.
+            cancel=True (bool): Cancel scheduled tasks before removing it from task handler.
+
+        Returns:
+            True (bool): if the removal completed successfully.
+        """
+        tasks_ids = tuple(self.tasks.keys())
+        for task_id in tasks_ids:
+            if cancel:
+                self.cancel(task_id)
+            del self.tasks[task_id]
+        tasks_ids = tuple(self.to_save.keys())
+        for task_id in tasks_ids:
+            del self.to_save[task_id]
+        if save:
+            self.save()
+        return True
+
     def do_task(self, task_id):
         """
         Execute the task (call its callback).

evennia/utils/tests/test_utils.py

@@ -417,32 +417,30 @@ class TestDelay(EvenniaTest):
         # test automated removal of stale tasks.
         t = utils.delay(timedelay, dummy_func, self.char1.dbref, persistent=True)
         t.cancel()
-        task_id = t.get_id()
         self.assertFalse(t.active())
         _TASK_HANDLER.clock.advance(timedelay)  # make time pass
-        self.assertTrue(task_id in _TASK_HANDLER.to_save)
+        self.assertTrue(t.get_id() in _TASK_HANDLER.to_save)
-        self.assertTrue(task_id in _TASK_HANDLER.tasks)
+        self.assertTrue(t.get_id() in _TASK_HANDLER.tasks)
             # add a task to test automatic removal
         _TASK_HANDLER._now = datetime.now() + timedelta(seconds=_TASK_HANDLER.stale_timeout + 6) # task handler time to 6 seconds after stale timeout
         t2 = utils.delay(timedelay, dummy_func, self.char1.dbref, persistent=True)
-        self.assertFalse(task_id in _TASK_HANDLER.to_save)
+        self.assertFalse(t.get_id() in _TASK_HANDLER.to_save)
-        self.assertFalse(task_id in _TASK_HANDLER.tasks)
+        self.assertFalse(t.get_id() in _TASK_HANDLER.tasks)
         self.assertEqual(self.char1.ndb.dummy_var, False)
         # test manual cleanup
         t2.cancel()
         _TASK_HANDLER.clock.advance(timedelay)  # advance twisted reactor time past callback time
         _TASK_HANDLER._now = datetime.now() + timedelta(seconds=30)  # set TaskHandler's time to 30 seconnds from now
-        task_id = t2.get_id()
             # test before stale_timeout time
         _TASK_HANDLER.clean_stale_tasks()  # cleanup of stale tasks in in the save method
             # still in the task handler because stale timeout has not been reached
-        self.assertTrue(task_id in _TASK_HANDLER.to_save)
+        self.assertTrue(t2.get_id() in _TASK_HANDLER.to_save)
-        self.assertTrue(task_id in _TASK_HANDLER.tasks)
+        self.assertTrue(t2.get_id() in _TASK_HANDLER.tasks)
             # advance past stale timeout
         _TASK_HANDLER._now = datetime.now() + timedelta(seconds=_TASK_HANDLER.stale_timeout + 6) # task handler time to 6 seconds after stale timeout
         _TASK_HANDLER.clean_stale_tasks()  # cleanup of stale tasks in in the save method
-        self.assertFalse(task_id in _TASK_HANDLER.to_save)
+        self.assertFalse(t2.get_id() in _TASK_HANDLER.to_save)
-        self.assertFalse(task_id in _TASK_HANDLER.tasks)
+        self.assertFalse(t2.get_id() in _TASK_HANDLER.tasks)
         self.char1.ndb.dummy_var = False
         _TASK_HANDLER._now = False
         # if _TASK_HANDLER.stale_timeout is 0 or less, automatic cleanup should not run
@@ -459,8 +457,23 @@ class TestDelay(EvenniaTest):
         self.assertTrue(t.get_id() in _TASK_HANDLER.to_save)
         self.assertTrue(t.get_id() in _TASK_HANDLER.tasks)
         self.assertEqual(self.char1.ndb.dummy_var, False)
-        t.remove()
+        _TASK_HANDLER.remove_all()
-        t2.remove()
         self.char1.ndb.dummy_var = False
         _TASK_HANDLER._now = False
         # replicate a restart
+        _TASK_HANDLER.remove_all()
+        _TASK_HANDLER.save()
+        self.assertFalse(_TASK_HANDLER.tasks)
+        self.assertFalse(_TASK_HANDLER.to_save)
+            # create a persistent task.
+        t = utils.delay(timedelay, dummy_func, self.char1.dbref, persistent=True)
+        _TASK_HANDLER.save()
+        _TASK_HANDLER.remove_all(False)  # remove all tasks, do not save this change.
+        _TASK_HANDLER.clock.advance(timedelay)  # advance twisted reactor time past callback time
+        self.assertEqual(self.char1.ndb.dummy_var, False)  # task has not run
+        _TASK_HANDLER.load()
+        _TASK_HANDLER.create_delays()
+        _TASK_HANDLER.clock.advance(timedelay)  # Clock must advance to trigger, even if past timedelay
+        self.assertEqual(self.char1.ndb.dummy_var, 'dummy_func ran')
+        _TASK_HANDLER.remove_all()
+        self.char1.ndb.dummy_var = False