diff options
| -rw-r--r-- | Lib/enum.py | 8 | ||||
| -rw-r--r-- | Lib/test/test_enum.py | 8 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2021-04-26-20-52-16.bpo-43945.NgERXO.rst | 2 |
3 files changed, 18 insertions, 0 deletions
diff --git a/Lib/enum.py b/Lib/enum.py index ca6aff6..bcf411c 100644 --- a/Lib/enum.py +++ b/Lib/enum.py @@ -1005,6 +1005,14 @@ class Enum(metaclass=EnumType): val = str(self) # mix-in branch else: + import warnings + warnings.warn( + "in 3.12 format() will use the enum member, not the enum member's value;\n" + "use a format specifier, such as :d for an IntEnum member, to maintain" + "the current display", + DeprecationWarning, + stacklevel=2, + ) cls = self._member_type_ val = self._value_ return cls.__format__(val, format_spec) diff --git a/Lib/test/test_enum.py b/Lib/test/test_enum.py index 4f28b80..983c54b 100644 --- a/Lib/test/test_enum.py +++ b/Lib/test/test_enum.py @@ -528,6 +528,14 @@ class TestEnum(unittest.TestCase): self.assertEqual(str(TestFloat.one), 'one') self.assertEqual('{}'.format(TestFloat.one), 'TestFloat success!') + @unittest.skipUnless( + sys.version_info[:2] < (3, 12), + 'mixin-format now uses member instead of member.value', + ) + def test_mixin_format_warning(self): + with self.assertWarns(DeprecationWarning): + self.assertEqual(f'{self.Grades.B}', '4') + def assertFormatIsValue(self, spec, member): self.assertEqual(spec.format(member), spec.format(member.value)) diff --git a/Misc/NEWS.d/next/Library/2021-04-26-20-52-16.bpo-43945.NgERXO.rst b/Misc/NEWS.d/next/Library/2021-04-26-20-52-16.bpo-43945.NgERXO.rst new file mode 100644 index 0000000..c01c200 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2021-04-26-20-52-16.bpo-43945.NgERXO.rst @@ -0,0 +1,2 @@ +[Enum] Deprecate non-standard mixin format() behavior: in 3.12 the enum +member, not the member's value, will be used for format() calls. |