User.enable_protocol: always call Protocol.create_for

...even if there's already a copy, since it might need to be reactivated

for #1130

models.py

@@ -537,7 +537,9 @@ def enable_protocol(self, to_proto):
         """
         added = False
 
-        if to_proto.LABEL in ids.COPIES_PROTOCOLS and not self.get_copy(to_proto):
+        if to_proto.LABEL in ids.COPIES_PROTOCOLS:
+            # do this even if there's an existing copy since we might need to
+            # reactivate it, which create_for should do
             to_proto.create_for(self)
 
         @ndb.transactional()

tests/test_dms.py

@@ -155,7 +155,7 @@ def test_receive_no_yes_sets_enabled_protocols(self):
         user = user.key.get()
         self.assertEqual(['fake'], user.enabled_protocols)
         self.assertTrue(user.is_enabled(Fake))
-        self.assertEqual([], Fake.created_for)
+        self.assertEqual(['efake:user'], Fake.created_for)
 
         # "no" DM should remove from enabled_protocols
         Follower.get_or_create(to=user, from_=alice)
@@ -164,7 +164,6 @@ def test_receive_no_yes_sets_enabled_protocols(self):
         self.assertEqual(('OK', 200), receive(from_user=user, obj=dm))
         user = user.key.get()
         self.assertEqual([], user.enabled_protocols)
-        self.assertEqual([], Fake.created_for)
         self.assertFalse(user.is_enabled(Fake))
 
         # ...and delete copy actor

tests/test_protocol.py

@@ -2923,15 +2923,14 @@ def test_follow_and_block_protocol_user_sets_enabled_protocols(self):
         user = user.key.get()
         self.assertEqual(['fake'], user.enabled_protocols)
         self.assertTrue(user.is_enabled(Fake))
-        self.assertEqual([], Fake.created_for)
+        self.assertEqual(['efake:user'], Fake.created_for)
 
         # block should remove from enabled_protocols
         Follower.get_or_create(to=user, from_=self.user)
         block['id'] += '2'
         self.assertEqual(('OK', 200), ExplicitFake.receive_as1(block))
         user = user.key.get()
         self.assertEqual([], user.enabled_protocols)
-        self.assertEqual([], Fake.created_for)
         self.assertFalse(user.is_enabled(Fake))
 
         # ...and delete copy actor
@@ -3042,6 +3041,44 @@ def test_follow_bot_user_overrides_nobot(self):
         self.assertTrue(user.is_enabled(Fake))
         self.assertEqual(['efake:user'], ExplicitFake.fetched)
 
+    def test_block_then_follow_protocol_user_recreates_copy(self):
+        # bot user
+        self.make_user('fa.brid.gy', cls=Web)
+
+        follow = {
+            'objectType': 'activity',
+            'verb': 'follow',
+            'id': 'efake:follow',
+            'actor': 'efake:user',
+            'object': 'fa.brid.gy',
+        }
+        block = {
+            'objectType': 'activity',
+            'verb': 'block',
+            'id': 'efake:block',
+            'actor': 'efake:user',
+            'object': 'fa.brid.gy',
+        }
+
+        copy = Target(uri='fake:user', protocol='fake')
+        user = self.make_user('efake:user', cls=ExplicitFake,
+                              enabled_protocols=['fake'], copies=[copy])
+        self.assertTrue(user.is_enabled(Fake))
+        self.assertEqual([copy], user.copies)
+
+        self.assertEqual(('OK', 200), ExplicitFake.receive_as1(block))
+        user = user.key.get()
+        self.assertFalse(user.is_enabled(Fake))
+        self.assertEqual([copy], user.copies)
+
+        # fake protocol isn't enabled yet, block should be a noop
+        ExplicitFake.fetchable = {'efake:user': {'profile': 'info'}}
+        _, code = ExplicitFake.receive_as1(follow)
+        self.assertEqual(204, code)
+        user = user.key.get()
+        self.assertEqual(['fake'], user.enabled_protocols)
+        self.assertEqual(['efake:user'], Fake.created_for)
+
     def test_receive_activity_lease(self):
         Follower.get_or_create(to=self.user, from_=self.alice)
 

tests/testutil.py

@@ -108,15 +108,17 @@ def bridged_web_url_for(cls, user, fallback=False):
 
     @classmethod
     def create_for(cls, user):
-        assert not user.get_copy(cls)
         id = user.key.id()
         logger.info(f'{cls.__name__}.create_for {id}')
         cls.created_for.append(id)
-        add(user.copies, Target(uri=ids.translate_user_id(id=id, from_=user, to=cls),
-                                protocol=cls.LABEL))
-        user.put()
 
-        if user.obj_key:
+        if not user.get_copy(cls):
+            copy = Target(uri=ids.translate_user_id(id=id, from_=user, to=cls),
+                          protocol=cls.LABEL)
+            add(user.copies, copy)
+            user.put()
+
+        if user.obj and not user.obj.get_copy(cls):
             profile_copy_id = ids.translate_object_id(
                 id=user.profile_id(), from_=user, to=cls)
             user.obj.add('copies', Target(uri=profile_copy_id, protocol=cls.LABEL))