cpython: 1d88d04aade2 (original) (raw)

Mercurial > cpython

changeset 85574:1d88d04aade2

Close #18924: Block naive attempts to change an Enum member. [#18924]

Ethan Furman ethan@stoneleaf.us
date	Fri, 06 Sep 2013 07:16:48 -0700
parents	587bdb940524
children	3070fdd58645
files	Lib/enum.py Lib/test/test_enum.py
diffstat	2 files changed, 18 insertions(+), 0 deletions(-)[+] [-] Lib/enum.py 13 Lib/test/test_enum.py 5

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line diff

--- a/Lib/enum.py +++ b/Lib/enum.py @@ -263,6 +263,19 @@ class EnumMeta(type): def repr(cls): return "<enum %r>" % cls.name

def setattr(cls, name, value):

   """Block attempts to reassign Enum members.[](#l1.8)

   A simple assignment to the class namespace only changes one of the[](#l1.10)

   several possible ways to get an Enum member from the Enum class,[](#l1.11)

   resulting in an inconsistent Enumeration.[](#l1.12)

```
   """[](#l1.14)
```

   member_map = cls.__dict__.get('_member_map_', {})[](#l1.15)

```
   if name in member_map:[](#l1.16)
```

       raise AttributeError('Cannot reassign members.')[](#l1.17)

   super().__setattr__(name, value)[](#l1.18)

+ def create(cls, class_name, names=None, *, module=None, type=None): """Convenience method to create a new Enum class.

--- a/Lib/test/test_enum.py +++ b/Lib/test/test_enum.py @@ -152,6 +152,11 @@ class TestEnum(unittest.TestCase): with self.assertRaises(AttributeError): Season.SPRING.value = 2

def test_changing_member(self):
```
   Season = self.Season[](#l2.8)
```

   with self.assertRaises(AttributeError):[](#l2.9)

       Season.WINTER = 'really cold'[](#l2.10)

+ def test_invalid_names(self): with self.assertRaises(ValueError): class Wrong(Enum):