bpo-42567: [Enum] call __init_subclass__ after members are added (GH-23714)
When creating an Enum, type.__new__ calls __init_subclass__, but at that point the members have not been added.
This patch suppresses the initial call, then manually calls the ancestor __init_subclass__ before returning the new Enum class.
diff --git a/Lib/test/test_enum.py b/Lib/test/test_enum.py
index ab4b52f..20bc5b3 100644
--- a/Lib/test/test_enum.py
+++ b/Lib/test/test_enum.py
@@ -2117,6 +2117,43 @@ class ThirdFailedStrEnum(StrEnum):
class ThirdFailedStrEnum(StrEnum):
one = '1'
two = b'2', 'ascii', 9
+
+ def test_init_subclass(self):
+ class MyEnum(Enum):
+ def __init_subclass__(cls, **kwds):
+ super(MyEnum, cls).__init_subclass__(**kwds)
+ self.assertFalse(cls.__dict__.get('_test', False))
+ cls._test1 = 'MyEnum'
+ #
+ class TheirEnum(MyEnum):
+ def __init_subclass__(cls, **kwds):
+ super().__init_subclass__(**kwds)
+ cls._test2 = 'TheirEnum'
+ class WhoseEnum(TheirEnum):
+ def __init_subclass__(cls, **kwds):
+ pass
+ class NoEnum(WhoseEnum):
+ ONE = 1
+ self.assertEqual(TheirEnum.__dict__['_test1'], 'MyEnum')
+ self.assertEqual(WhoseEnum.__dict__['_test1'], 'MyEnum')
+ self.assertEqual(WhoseEnum.__dict__['_test2'], 'TheirEnum')
+ self.assertFalse(NoEnum.__dict__.get('_test1', False))
+ self.assertFalse(NoEnum.__dict__.get('_test2', False))
+ #
+ class OurEnum(MyEnum):
+ def __init_subclass__(cls, **kwds):
+ cls._test2 = 'OurEnum'
+ class WhereEnum(OurEnum):
+ def __init_subclass__(cls, **kwds):
+ pass
+ class NeverEnum(WhereEnum):
+ ONE = 'one'
+ self.assertEqual(OurEnum.__dict__['_test1'], 'MyEnum')
+ self.assertFalse(WhereEnum.__dict__.get('_test1', False))
+ self.assertEqual(WhereEnum.__dict__['_test2'], 'OurEnum')
+ self.assertFalse(NeverEnum.__dict__.get('_test1', False))
+ self.assertFalse(NeverEnum.__dict__.get('_test2', False))
+
class TestOrder(unittest.TestCase):
@@ -2573,6 +2610,42 @@ def cycle_enum():
'at least one thread failed while creating composite members')
self.assertEqual(256, len(seen), 'too many composite members created')
+ def test_init_subclass(self):
+ class MyEnum(Flag):
+ def __init_subclass__(cls, **kwds):
+ super().__init_subclass__(**kwds)
+ self.assertFalse(cls.__dict__.get('_test', False))
+ cls._test1 = 'MyEnum'
+ #
+ class TheirEnum(MyEnum):
+ def __init_subclass__(cls, **kwds):
+ super(TheirEnum, cls).__init_subclass__(**kwds)
+ cls._test2 = 'TheirEnum'
+ class WhoseEnum(TheirEnum):
+ def __init_subclass__(cls, **kwds):
+ pass
+ class NoEnum(WhoseEnum):
+ ONE = 1
+ self.assertEqual(TheirEnum.__dict__['_test1'], 'MyEnum')
+ self.assertEqual(WhoseEnum.__dict__['_test1'], 'MyEnum')
+ self.assertEqual(WhoseEnum.__dict__['_test2'], 'TheirEnum')
+ self.assertFalse(NoEnum.__dict__.get('_test1', False))
+ self.assertFalse(NoEnum.__dict__.get('_test2', False))
+ #
+ class OurEnum(MyEnum):
+ def __init_subclass__(cls, **kwds):
+ cls._test2 = 'OurEnum'
+ class WhereEnum(OurEnum):
+ def __init_subclass__(cls, **kwds):
+ pass
+ class NeverEnum(WhereEnum):
+ ONE = 1
+ self.assertEqual(OurEnum.__dict__['_test1'], 'MyEnum')
+ self.assertFalse(WhereEnum.__dict__.get('_test1', False))
+ self.assertEqual(WhereEnum.__dict__['_test2'], 'OurEnum')
+ self.assertFalse(NeverEnum.__dict__.get('_test1', False))
+ self.assertFalse(NeverEnum.__dict__.get('_test2', False))
+
class TestIntFlag(unittest.TestCase):
"""Tests of the IntFlags."""