No longer support 'util.class_or_instance_method' propagating on the …

…descriptor protocol
friedkeenan · Jan 3, 2025 · 93ce50f · 93ce50f
1 parent 44e030d
commit 93ce50f
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Showing 2 changed files with 13 additions and 21 deletions.
diff --git a/pak/util/decorators.py b/pak/util/decorators.py
@@ -1,6 +1,8 @@
 """Custom decorators."""
 
 import functools
+import types
+
 from collections.abc import Hashable
 
 __all__ = [
@@ -139,12 +141,17 @@ def __set_name__(self, owner, name):
             raise TypeError(f"{type(self).__qualname__} '{owner.__qualname__}.{name}' must have an instance method")
 
     def __get__(self, instance, owner=None):
-        # 'classmethod' in fact propagates the '__get__' call instead of
-        # just returning a bound method. This allows users to create
-        # "class properties" by combining 'classmethod' and 'property'.
-        # We support the same here.
+        # From Python 3.9 to Python 3.12, 'classmethod'
+        # in fact propagates the '__get__' call instead
+        # of just returning a bound method. This allows
+        # users to create "class properties" by combining
+        # 'classmethod' and 'property'.
+        #
+        # We do not model the same, as it was decided that
+        # that design was unsound and was deprecated in
+        # Python 3.11 and then removed in Python 3.13.
 
         if instance is None:
-            return self._class_method.__get__(owner, owner)
+            return types.MethodType(self._class_method, owner)
 
-        return self._instance_method.__get__(instance, owner)
+        return types.MethodType(self._instance_method, instance)
diff --git a/tests/test_utils/test_decorators.py b/tests/test_utils/test_decorators.py
@@ -74,21 +74,6 @@ class MissingInstanceMethod:
             def method(cls):
                 pass
 
-def test_class_or_instance_method_descriptor_propagate():
-    class Test:
-        @pak.util.class_or_instance_method
-        @property
-        def attr(cls):
-            return "class"
-
-        @attr.instance_method
-        @property
-        def attr(self):
-            return "instance"
-
-    assert Test.attr   == "class"
-    assert Test().attr == "instance"
-
 def test_class_or_instance_method_copy():
     class Test:
         @pak.util.class_or_instance_method