[3.10] bpo-43945: [Enum] reduce scope of new format() behavior (GH-26752)
* [Enum] reduce scope of new format behavior
Instead of treating all Enums the same for format(), only user mixed-in
enums will be affected. In other words, IntEnum and IntFlag will not be
changing the format() behavior, due to the requirement that they be
drop-in replacements of existing integer constants.
If a user creates their own integer-based enum, then the new behavior
will apply:
class Grades(int, Enum):
A = 5
B = 4
C = 3
D = 2
F = 0
Now: format(Grades.B) -> DeprecationWarning and '4'
3.12: -> no warning, and 'B'.
(cherry picked from commit f60b07ab6c943fce084772c3c7731ab3bbd213ff)
Co-authored-by: Ethan Furman <ethan@stoneleaf.us>diff --git a/Lib/test/test_enum.py b/Lib/test/test_enum.py
index c4c458e..0267ff5 100644
--- a/Lib/test/test_enum.py
+++ b/Lib/test/test_enum.py
@@ -557,16 +557,27 @@ def __format__(self, spec):
'mixin-format is still using member.value',
)
def test_mixin_format_warning(self):
- with self.assertWarns(DeprecationWarning):
- self.assertEqual(f'{self.Grades.B}', 'Grades.B')
+ class Grades(int, Enum):
+ A = 5
+ B = 4
+ C = 3
+ D = 2
+ F = 0
+ self.assertEqual(f'{self.Grades.B}', 'B')
@unittest.skipIf(
python_version >= (3, 12),
'mixin-format now uses member instead of member.value',
)
def test_mixin_format_warning(self):
+ class Grades(int, Enum):
+ A = 5
+ B = 4
+ C = 3
+ D = 2
+ F = 0
with self.assertWarns(DeprecationWarning):
- self.assertEqual(f'{self.Grades.B}', '4')
+ self.assertEqual(f'{Grades.B}', '4')
def assertFormatIsValue(self, spec, member):
if python_version < (3, 12) and (not spec or spec in ('{}','{:}')):
@@ -599,7 +610,12 @@ def test_format_enum_float(self):
self.assertFormatIsValue('{:f}', Konstants.TAU)
def test_format_enum_int(self):
- Grades = self.Grades
+ class Grades(int, Enum):
+ A = 5
+ B = 4
+ C = 3
+ D = 2
+ F = 0
self.assertFormatIsValue('{}', Grades.C)
self.assertFormatIsValue('{:}', Grades.C)
self.assertFormatIsValue('{:20}', Grades.C)
@@ -2236,8 +2252,10 @@ class GoodStrEnum(StrEnum):
four = b'4', 'latin1', 'strict'
self.assertEqual(GoodStrEnum.one, '1')
self.assertEqual(str(GoodStrEnum.one), '1')
+ self.assertEqual('{}'.format(GoodStrEnum.one), '1')
self.assertEqual(GoodStrEnum.one, str(GoodStrEnum.one))
self.assertEqual(GoodStrEnum.one, '{}'.format(GoodStrEnum.one))
+ self.assertEqual(repr(GoodStrEnum.one), 'GoodStrEnum.one')
#
class DumbMixin:
def __str__(self):
@@ -2287,6 +2305,132 @@ class ThirdFailedStrEnum(StrEnum):
one = '1'
two = b'2', 'ascii', 9
+ @unittest.skipIf(
+ python_version >= (3, 12),
+ 'mixin-format now uses member instead of member.value',
+ )
+ def test_custom_strenum_with_warning(self):
+ class CustomStrEnum(str, Enum):
+ pass
+ class OkayEnum(CustomStrEnum):
+ one = '1'
+ two = '2'
+ three = b'3', 'ascii'
+ four = b'4', 'latin1', 'strict'
+ self.assertEqual(OkayEnum.one, '1')
+ self.assertEqual(str(OkayEnum.one), 'one')
+ with self.assertWarns(DeprecationWarning):
+ self.assertEqual('{}'.format(OkayEnum.one), '1')
+ self.assertEqual(OkayEnum.one, '{}'.format(OkayEnum.one))
+ self.assertEqual(repr(OkayEnum.one), 'OkayEnum.one')
+ #
+ class DumbMixin:
+ def __str__(self):
+ return "don't do this"
+ class DumbStrEnum(DumbMixin, CustomStrEnum):
+ five = '5'
+ six = '6'
+ seven = '7'
+ self.assertEqual(DumbStrEnum.seven, '7')
+ self.assertEqual(str(DumbStrEnum.seven), "don't do this")
+ #
+ class EnumMixin(Enum):
+ def hello(self):
+ print('hello from %s' % (self, ))
+ class HelloEnum(EnumMixin, CustomStrEnum):
+ eight = '8'
+ self.assertEqual(HelloEnum.eight, '8')
+ self.assertEqual(str(HelloEnum.eight), 'eight')
+ #
+ class GoodbyeMixin:
+ def goodbye(self):
+ print('%s wishes you a fond farewell')
+ class GoodbyeEnum(GoodbyeMixin, EnumMixin, CustomStrEnum):
+ nine = '9'
+ self.assertEqual(GoodbyeEnum.nine, '9')
+ self.assertEqual(str(GoodbyeEnum.nine), 'nine')
+ #
+ class FirstFailedStrEnum(CustomStrEnum):
+ one = 1 # this will become '1'
+ two = '2'
+ class SecondFailedStrEnum(CustomStrEnum):
+ one = '1'
+ two = 2, # this will become '2'
+ three = '3'
+ class ThirdFailedStrEnum(CustomStrEnum):
+ one = '1'
+ two = 2 # this will become '2'
+ with self.assertRaisesRegex(TypeError, '.encoding. must be str, not '):
+ class ThirdFailedStrEnum(CustomStrEnum):
+ one = '1'
+ two = b'2', sys.getdefaultencoding
+ with self.assertRaisesRegex(TypeError, '.errors. must be str, not '):
+ class ThirdFailedStrEnum(CustomStrEnum):
+ one = '1'
+ two = b'2', 'ascii', 9
+
+ @unittest.skipIf(
+ python_version < (3, 12),
+ 'mixin-format currently uses member.value',
+ )
+ def test_custom_strenum(self):
+ class CustomStrEnum(str, Enum):
+ pass
+ class OkayEnum(CustomStrEnum):
+ one = '1'
+ two = '2'
+ three = b'3', 'ascii'
+ four = b'4', 'latin1', 'strict'
+ self.assertEqual(OkayEnum.one, '1')
+ self.assertEqual(str(OkayEnum.one), 'one')
+ self.assertEqual('{}'.format(OkayEnum.one), 'one')
+ self.assertEqual(repr(OkayEnum.one), 'OkayEnum.one')
+ #
+ class DumbMixin:
+ def __str__(self):
+ return "don't do this"
+ class DumbStrEnum(DumbMixin, CustomStrEnum):
+ five = '5'
+ six = '6'
+ seven = '7'
+ self.assertEqual(DumbStrEnum.seven, '7')
+ self.assertEqual(str(DumbStrEnum.seven), "don't do this")
+ #
+ class EnumMixin(Enum):
+ def hello(self):
+ print('hello from %s' % (self, ))
+ class HelloEnum(EnumMixin, CustomStrEnum):
+ eight = '8'
+ self.assertEqual(HelloEnum.eight, '8')
+ self.assertEqual(str(HelloEnum.eight), 'eight')
+ #
+ class GoodbyeMixin:
+ def goodbye(self):
+ print('%s wishes you a fond farewell')
+ class GoodbyeEnum(GoodbyeMixin, EnumMixin, CustomStrEnum):
+ nine = '9'
+ self.assertEqual(GoodbyeEnum.nine, '9')
+ self.assertEqual(str(GoodbyeEnum.nine), 'nine')
+ #
+ class FirstFailedStrEnum(CustomStrEnum):
+ one = 1 # this will become '1'
+ two = '2'
+ class SecondFailedStrEnum(CustomStrEnum):
+ one = '1'
+ two = 2, # this will become '2'
+ three = '3'
+ class ThirdFailedStrEnum(CustomStrEnum):
+ one = '1'
+ two = 2 # this will become '2'
+ with self.assertRaisesRegex(TypeError, '.encoding. must be str, not '):
+ class ThirdFailedStrEnum(CustomStrEnum):
+ one = '1'
+ two = b'2', sys.getdefaultencoding
+ with self.assertRaisesRegex(TypeError, '.errors. must be str, not '):
+ class ThirdFailedStrEnum(CustomStrEnum):
+ one = '1'
+ two = b'2', 'ascii', 9
+
def test_missing_value_error(self):
with self.assertRaisesRegex(TypeError, "_value_ not set in __new__"):
class Combined(str, Enum):
@@ -3080,15 +3224,19 @@ def test_repr(self):
self.assertEqual(repr(~(Open.WO | Open.CE)), 'Open.RW')
self.assertEqual(repr(Open(~4)), '-5')
- @unittest.skipUnless(
- python_version < (3, 12),
- 'mixin-format now uses member instead of member.value',
- )
def test_format(self):
- with self.assertWarns(DeprecationWarning):
- Perm = self.Perm
- self.assertEqual(format(Perm.R, ''), '4')
- self.assertEqual(format(Perm.R | Perm.X, ''), '5')
+ Perm = self.Perm
+ self.assertEqual(format(Perm.R, ''), '4')
+ self.assertEqual(format(Perm.R | Perm.X, ''), '5')
+ #
+ class NewPerm(IntFlag):
+ R = 1 << 2
+ W = 1 << 1
+ X = 1 << 0
+ def __str__(self):
+ return self._name_
+ self.assertEqual(format(NewPerm.R, ''), 'R')
+ self.assertEqual(format(NewPerm.R | Perm.X, ''), 'R|X')
def test_or(self):
Perm = self.Perm
@@ -3979,10 +4127,6 @@ def test_convert_raise(self):
('test.test_enum', '__main__')[__name__=='__main__'],
filter=lambda x: x.startswith('CONVERT_TEST_'))
- @unittest.skipUnless(
- python_version < (3, 12),
- 'mixin-format now uses member instead of member.value',
- )
def test_convert_repr_and_str(self):
module = ('test.test_enum', '__main__')[__name__=='__main__']
test_type = enum.IntEnum._convert_(
@@ -3991,8 +4135,7 @@ def test_convert_repr_and_str(self):
filter=lambda x: x.startswith('CONVERT_STRING_TEST_'))
self.assertEqual(repr(test_type.CONVERT_STRING_TEST_NAME_A), '%s.CONVERT_STRING_TEST_NAME_A' % module)
self.assertEqual(str(test_type.CONVERT_STRING_TEST_NAME_A), 'CONVERT_STRING_TEST_NAME_A')
- with self.assertWarns(DeprecationWarning):
- self.assertEqual(format(test_type.CONVERT_STRING_TEST_NAME_A), '5')
+ self.assertEqual(format(test_type.CONVERT_STRING_TEST_NAME_A), '5')
# global names for StrEnum._convert_ test
CONVERT_STR_TEST_2 = 'goodbye'