gh-93910: [Enum] restore member.member restriction while keeping performance boost (GH-94913)

1 files changed, 8 insertions, 0 deletions

diff --git a/Lib/enum.py b/Lib/enum.py
index 652878c..a4f1f09 100644
--- a/Lib/enum.py
+++ b/Lib/enum.py
@@ -1101,6 +1101,14 @@ class Enum(metaclass=EnumType):
     def __init__(self, *args, **kwds):
         pass
 
+    def __getattribute__(self, name):
+        self_dict = super().__getattribute__('__dict__')
+        cls = super().__getattribute__('__class__')
+        value = super().__getattribute__(name)
+        if isinstance(value, cls) and name not in self_dict and name in self._member_names_:
+            raise AttributeError("<enum '%s'> member has no attribute %r" % (cls.__name__, name))
+        return super().__getattribute__(name)
+
     def _generate_next_value_(name, start, count, last_values):
         """
         Generate the next value when not given.