diff --git a/Lib/enum.py b/Lib/enum.py index f6c7e8b23341395..d34e45cfd554ce7 100644 --- a/Lib/enum.py +++ b/Lib/enum.py @@ -112,7 +112,7 @@ def __setitem__(self, key, value): key = '_order_' elif key in self._member_names: # descriptor overwriting an enum? - raise TypeError('Attempted to reuse key: %r' % key) + raise TypeError('%r already defined as: %r' % (key, self[key])) elif key in self._ignore: pass elif not _is_descriptor(value): @@ -133,6 +133,16 @@ def __setitem__(self, key, value): self._last_values.append(value) super().__setitem__(key, value) + def update(self, members, **more_members): + try: + for name in members.keys(): + self[name] = members[name] + except AttributeError: + for name, value in members: + self[name] = value + for name, value in more_members.items(): + self[name] = value + # Dummy value for Enum as EnumMeta explicitly checks for it, but of course # until EnumMeta finishes running the first time the Enum class doesn't exist. diff --git a/Lib/test/test_enum.py b/Lib/test/test_enum.py index ab4b52f78527302..8cd6747fe200df3 100644 --- a/Lib/test/test_enum.py +++ b/Lib/test/test_enum.py @@ -2118,6 +2118,34 @@ class ThirdFailedStrEnum(StrEnum): one = '1' two = b'2', 'ascii', 9 + def test_dynamic_members_with_static_methods(self): + # + foo_defines = {'FOO_CAT': 'aloof', 'BAR_DOG': 'friendly', 'FOO_HORSE': 'big'} + class Foo(Enum): + vars().update({ + k: v + for k, v in foo_defines.items() + if k.startswith('FOO_') + }) + def upper(self): + return self.value.upper() + self.assertEqual(list(Foo), [Foo.FOO_CAT, Foo.FOO_HORSE]) + self.assertEqual(Foo.FOO_CAT.value, 'aloof') + self.assertEqual(Foo.FOO_HORSE.upper(), 'BIG') + # + with self.assertRaisesRegex(TypeError, "'FOO_CAT' already defined as: 'aloof'"): + class FooBar(Enum): + vars().update({ + k: v + for k, v in foo_defines.items() + if k.startswith('FOO_') + }, + **{'FOO_CAT': 'small'}, + ) + def upper(self): + return self.value.upper() + + class TestOrder(unittest.TestCase): def test_same_members(self): diff --git a/Misc/NEWS.d/next/Library/2020-12-09-14-15-48.bpo-34750.x8TASR.rst b/Misc/NEWS.d/next/Library/2020-12-09-14-15-48.bpo-34750.x8TASR.rst new file mode 100644 index 000000000000000..c98ba14797af95f --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-12-09-14-15-48.bpo-34750.x8TASR.rst @@ -0,0 +1 @@ +[Enum] `_EnumDict.update()` is now supported