Fixed #429.

Author: jordanbriere

Diff for: addons/source-python/packages/source-python/core/__init__.py

@@ -93,7 +93,7 @@
 # =============================================================================
 # >> CLASSES
 # =============================================================================
-class AutoUnload(object):
+class AutoUnload:
     """Class used to auto unload specific instances.
 
     Each inheriting class must implement an _unload_instance method.
@@ -144,12 +144,6 @@ def _add_instance(self, caller):
 
     def _unload_instance(self):
         """Base _unload_instance implementation."""
-        raise NotImplementedError(
-            'Class "{0}" from file "{1}" does not '.format(
-                self.__class__.__name__, sys.modules[
-                    self.__class__.__module__].__file__.split(
-                    'plugins', 1)[1][1:]) +
-            'have its own implementation of an _unload_instance method.')
 
 
 class WeakAutoUnload(AutoUnload):

Diff for: addons/source-python/packages/source-python/cvars/__init__.py

@@ -6,6 +6,8 @@
 # >> IMPORTS
 # =============================================================================
 # Source.Python Imports
+#   Core
+from core import AutoUnload
 #   Cvars
 from _cvars import ConVar
 from _cvars import SP_CVAR_DLL_IDENTIFIER
@@ -28,3 +30,11 @@
            'SP_CVAR_DLL_IDENTIFIER',
            'cvar',
            )
+
+
+# =============================================================================
+# >> INITIALIZATION
+# =============================================================================
+# Inject AutoUnload into ConVar's inheritance tree so that custom instances
+#   are kept alive until the plugin creating them remains loaded.
+ConVar.__bases__ = (AutoUnload,) + ConVar.__bases__

Diff for: addons/source-python/packages/source-python/cvars/public.py

@@ -22,7 +22,7 @@
 # =============================================================================
 # >> CLASSES
 # =============================================================================
-class PublicConVar(AutoUnload, ConVar):
+class PublicConVar(ConVar):
     """Class used to set the notify flag on load/unload."""
 
     def __init__(