Trying to run DoormanQueuedJobTask without descriptor set

[nathancox]

I'm having an issue publishing pages via embargo. It doesn't happen every time but it often fails and gives errors about descriptor not being defined.

I give a page an embargo time then run /dev/tasks/ProcessJobQueueTask and usually within a few tries it will have this error and fail to publish:

[Notice] Trying to get property of non-object
GET /dev/tasks/ProcessJobQueueTask
Line 216 in /var/www/html/vendor/symbiote/silverstripe-queuedjobs/src/Jobs/DoormanQueuedJobTask.php

Source
207     {
208         $this->refreshDescriptor();
209 
210         // Treat completed jobs as cancelled when it comes to how Doorman handles picking up jobs to run
211         $cancelledStates = [
212             QueuedJob::STATUS_CANCELLED,
213             QueuedJob::STATUS_COMPLETE,
214         ];
215 
216         return in_array($this->descriptor->JobStatus, $cancelledStates, true);
217     }
218 }

So far it only seems to happen when the cwp-core 2.2.0 module is installed but I can't see any reason why that would be.

I've uploaded the most minimal test case I could to https://github.com/nathancox/queuedjobtest along with instructions to reproduce the error.