From 5e2372f79ddcc9bbbb76bb9e16739974d400d531 Mon Sep 17 00:00:00 2001
From: Griatch <griatch@gmail.com>
Date: Mon, 7 Feb 2022 20:45:48 +0100
Subject: [PATCH] Make sure Typeclass.at_init() is always called on cache
 initialization for any typeclass. Resolve #2641

---
 evennia/scripts/models.py        | 2 --
 evennia/scripts/scripts.py       | 8 ++++++++
 evennia/scripts/tests.py         | 8 +++++---
 evennia/server/server.py         | 8 +++++---
 evennia/typeclasses/models.py    | 8 ++++++++
 evennia/utils/idmapper/models.py | 1 +
 6 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/evennia/scripts/models.py b/evennia/scripts/models.py
index a91046198d..29ad388b15 100644
--- a/evennia/scripts/models.py
+++ b/evennia/scripts/models.py
@@ -157,8 +157,6 @@ class ScriptDB(TypedObject):
             # deprecated ...
             pass
         if isinstance(value, (str, int)):
-            from evennia.objects.models import ObjectDB
-
             value = to_str(value)
             if value.isdigit() or value.startswith("#"):
                 dbid = dbref(value, reqhash=False)
diff --git a/evennia/scripts/scripts.py b/evennia/scripts/scripts.py
index 43f06e7830..eeed1473c9 100644
--- a/evennia/scripts/scripts.py
+++ b/evennia/scripts/scripts.py
@@ -473,6 +473,14 @@ class ScriptBase(ScriptDB, metaclass=TypeclassBase):
         super().delete()
         return True
 
+    def at_init(self):
+        """
+        Called when the Script is cached in the idmapper. This is usually more reliable
+        than overriding `__init__` since the latter can be called at unexpected times.
+
+        """
+        pass
+
     def at_script_creation(self):
         """
         Should be overridden in child.
diff --git a/evennia/scripts/tests.py b/evennia/scripts/tests.py
index 305826fa2e..d639c5ca1d 100644
--- a/evennia/scripts/tests.py
+++ b/evennia/scripts/tests.py
@@ -11,9 +11,11 @@ from evennia.scripts.scripts import DoNothing, ExtendedLoopingCall
 class TestScript(BaseEvenniaTest):
     def test_create(self):
         "Check the script can be created via the convenience method."
-        obj, errors = DefaultScript.create("useless-machine")
-        self.assertTrue(obj, errors)
-        self.assertFalse(errors, errors)
+        with mock.patch("evennia.scripts.scripts.DefaultScript.at_init") as mockinit:
+            obj, errors = DefaultScript.create("useless-machine")
+            self.assertTrue(obj, errors)
+            self.assertFalse(errors, errors)
+            mockinit.assert_called()
 
 
 class TestScriptDB(TestCase):
diff --git a/evennia/server/server.py b/evennia/server/server.py
index 9b749f2f63..af7aeea343 100644
--- a/evennia/server/server.py
+++ b/evennia/server/server.py
@@ -395,7 +395,7 @@ class Evennia:
             mode (str): One of shutdown, reload or reset
 
         """
-        from evennia.objects.models import ObjectDB
+        from evennia.typeclasses.models import TypedObject
 
         # start server time and maintenance task
         self.maintenance_task = LoopingCall(_server_maintenance)
@@ -404,8 +404,10 @@ class Evennia:
         # update eventual changed defaults
         self.update_defaults()
 
-        [o.at_init() for o in ObjectDB.get_all_cached_instances()]
-        [p.at_init() for p in AccountDB.get_all_cached_instances()]
+        # run at_init() on all cached entities on reconnect
+        [[entity.at_init()
+          for entity in typeclass_db.get_all_cached_instances()]
+          for typeclass_db in TypedObject.__subclasses__()]
 
         # call correct server hook based on start file value
         if mode == "reload":
diff --git a/evennia/typeclasses/models.py b/evennia/typeclasses/models.py
index f47f9b267e..6512d30527 100644
--- a/evennia/typeclasses/models.py
+++ b/evennia/typeclasses/models.py
@@ -485,6 +485,14 @@ class TypedObject(SharedMemoryModel):
     # Object manipulation methods
     #
 
+    def at_init(self):
+        """
+        Called when this object is loaded into cache. This is  more reliable
+        than to override `__init__`.
+
+        """
+        pass
+
     @classmethod
     def search(cls, query, **kwargs):
         """
diff --git a/evennia/utils/idmapper/models.py b/evennia/utils/idmapper/models.py
index c62f3798b6..f9c187f98c 100644
--- a/evennia/utils/idmapper/models.py
+++ b/evennia/utils/idmapper/models.py
@@ -313,6 +313,7 @@ class SharedMemoryModel(Model, metaclass=SharedMemoryModelBase):
         """
         pk = instance._get_pk_val()
         if pk is not None:
+            new = new or pk not in cls.__dbclass__.__instance_cache__
             cls.__dbclass__.__instance_cache__[pk] = instance
             if new:
                 try: