set override_of on new decision

src/olympia/abuse/models.py

@@ -338,7 +338,7 @@ def create_and_execute_decision(
                 'private_notes': decision_notes[
                     : ContentDecision._meta.get_field('reasoning').max_length
                 ],
-                'override_of': None,
+                'override_of': job.final_decision if job else None,
                 'cinder_job': job,
                 'from_job_queue': job_queue,
             },

src/olympia/abuse/tests/test_models.py

@@ -1403,6 +1403,45 @@ def test_create_and_execute_decision_no_job(self):
         assert notify_mock.call_count == 1
         assert list(decision.policies.all()) == [policy_a, policy_b]
 
+    def test_create_and_execute_decision_override_decision(self):
+        target = user_factory()
+        cinder_job = CinderJob.objects.create(job_id='1234')
+        earlier_decision = ContentDecision.objects.create(
+            cinder_id='1234',
+            action=DECISION_ACTIONS.AMO_APPROVE,
+            cinder_job=cinder_job,
+            user=target,
+        )
+        AbuseReport.objects.create(user=target, cinder_job=cinder_job)
+        policy_a = CinderPolicy.objects.create(uuid='123-45', name='aaa', text='AAA')
+        policy_b = CinderPolicy.objects.create(uuid='678-90', name='bbb', text='BBB')
+
+        with (
+            mock.patch.object(ContentActionBanUser, 'process_action') as action_mock,
+            mock.patch.object(ContentActionBanUser, 'notify_owners') as notify_mock,
+        ):
+            action_mock.return_value = None
+            CinderJob.create_and_execute_decision(
+                cinder_job,
+                target=target,
+                decision_cinder_id='12345',
+                decision_action=DECISION_ACTIONS.AMO_BAN_USER.value,
+                decision_notes='teh notes',
+                policy_ids=['123-45', '678-90'],
+                job_queue='some-cinder-queue',
+            )
+        assert cinder_job.decision == earlier_decision
+        assert cinder_job.final_decision.cinder_id == '12345'
+        assert cinder_job.final_decision.action == DECISION_ACTIONS.AMO_BAN_USER
+        assert cinder_job.final_decision.private_notes == 'teh notes'
+        assert cinder_job.final_decision.reasoning == ''
+        assert cinder_job.final_decision.from_job_queue == 'some-cinder-queue'
+        assert cinder_job.final_decision.user == target
+        assert cinder_job.final_decision.override_of == earlier_decision
+        assert action_mock.call_count == 1
+        assert notify_mock.call_count == 1
+        assert list(cinder_job.final_decision.policies.all()) == [policy_a, policy_b]
+
     @override_switch('dsa-cinder-forwarded-review', active=True)
     def test_process_queue_move_into_reviewer_handled(self):
         addon = addon_factory(file_kw={'is_signed': True})