[Python-checkins] gh-103365: [Enum] STRICT boundary corrections (GH-103494)
ethanfurman
webhook-mailer at python.org
Thu Apr 13 11:24:40 EDT 2023
https://github.com/python/cpython/commit/2194071540313e2bbdc7214d77453b9ce3034a5c
commit: 2194071540313e2bbdc7214d77453b9ce3034a5c
branch: main
author: Ethan Furman <ethan at stoneleaf.us>
committer: ethanfurman <ethan at stoneleaf.us>
date: 2023-04-13T08:24:33-07:00
summary:
gh-103365: [Enum] STRICT boundary corrections (GH-103494)
STRICT boundary:
- fix bitwise operations
- make default for Flag
files:
A Misc/NEWS.d/next/Library/2023-04-12-17-59-55.gh-issue-103365.UBEE0U.rst
M Doc/library/enum.rst
M Lib/enum.py
M Lib/test/test_enum.py
diff --git a/Doc/library/enum.rst b/Doc/library/enum.rst
index c690c837309e..07acf9da33e2 100644
--- a/Doc/library/enum.rst
+++ b/Doc/library/enum.rst
@@ -696,7 +696,8 @@ Data Types
.. attribute:: STRICT
- Out-of-range values cause a :exc:`ValueError` to be raised::
+ Out-of-range values cause a :exc:`ValueError` to be raised. This is the
+ default for :class:`Flag`::
>>> from enum import Flag, STRICT, auto
>>> class StrictFlag(Flag, boundary=STRICT):
@@ -714,7 +715,7 @@ Data Types
.. attribute:: CONFORM
Out-of-range values have invalid values removed, leaving a valid *Flag*
- value. This is the default for :class:`Flag`::
+ value::
>>> from enum import Flag, CONFORM, auto
>>> class ConformFlag(Flag, boundary=CONFORM):
diff --git a/Lib/enum.py b/Lib/enum.py
index 10902c4b202a..432d7456b4b9 100644
--- a/Lib/enum.py
+++ b/Lib/enum.py
@@ -275,6 +275,13 @@ def __set_name__(self, enum_class, member_name):
enum_member.__objclass__ = enum_class
enum_member.__init__(*args)
enum_member._sort_order_ = len(enum_class._member_names_)
+
+ if Flag is not None and issubclass(enum_class, Flag):
+ enum_class._flag_mask_ |= value
+ if _is_single_bit(value):
+ enum_class._singles_mask_ |= value
+ enum_class._all_bits_ = 2 ** ((enum_class._flag_mask_).bit_length()) - 1
+
# If another member with the same value was already defined, the
# new member becomes an alias to the existing one.
try:
@@ -532,12 +539,8 @@ def __new__(metacls, cls, bases, classdict, *, boundary=None, _simple=False, **k
classdict['_use_args_'] = use_args
#
# convert future enum members into temporary _proto_members
- # and record integer values in case this will be a Flag
- flag_mask = 0
for name in member_names:
value = classdict[name]
- if isinstance(value, int):
- flag_mask |= value
classdict[name] = _proto_member(value)
#
# house-keeping structures
@@ -554,8 +557,9 @@ def __new__(metacls, cls, bases, classdict, *, boundary=None, _simple=False, **k
boundary
or getattr(first_enum, '_boundary_', None)
)
- classdict['_flag_mask_'] = flag_mask
- classdict['_all_bits_'] = 2 ** ((flag_mask).bit_length()) - 1
+ classdict['_flag_mask_'] = 0
+ classdict['_singles_mask_'] = 0
+ classdict['_all_bits_'] = 0
classdict['_inverted_'] = None
try:
exc = None
@@ -644,21 +648,10 @@ def __new__(metacls, cls, bases, classdict, *, boundary=None, _simple=False, **k
):
delattr(enum_class, '_boundary_')
delattr(enum_class, '_flag_mask_')
+ delattr(enum_class, '_singles_mask_')
delattr(enum_class, '_all_bits_')
delattr(enum_class, '_inverted_')
elif Flag is not None and issubclass(enum_class, Flag):
- # ensure _all_bits_ is correct and there are no missing flags
- single_bit_total = 0
- multi_bit_total = 0
- for flag in enum_class._member_map_.values():
- flag_value = flag._value_
- if _is_single_bit(flag_value):
- single_bit_total |= flag_value
- else:
- # multi-bit flags are considered aliases
- multi_bit_total |= flag_value
- enum_class._flag_mask_ = single_bit_total
- #
# set correct __iter__
member_list = [m._value_ for m in enum_class]
if member_list != sorted(member_list):
@@ -1303,8 +1296,8 @@ def _reduce_ex_by_global_name(self, proto):
class FlagBoundary(StrEnum):
"""
control how out of range values are handled
- "strict" -> error is raised
- "conform" -> extra bits are discarded [default for Flag]
+ "strict" -> error is raised [default for Flag]
+ "conform" -> extra bits are discarded
"eject" -> lose flag status
"keep" -> keep flag status and all bits [default for IntFlag]
"""
@@ -1315,7 +1308,7 @@ class FlagBoundary(StrEnum):
STRICT, CONFORM, EJECT, KEEP = FlagBoundary
-class Flag(Enum, boundary=CONFORM):
+class Flag(Enum, boundary=STRICT):
"""
Support for flags
"""
@@ -1394,6 +1387,7 @@ def _missing_(cls, value):
# - value must not include any skipped flags (e.g. if bit 2 is not
# defined, then 0d10 is invalid)
flag_mask = cls._flag_mask_
+ singles_mask = cls._singles_mask_
all_bits = cls._all_bits_
neg_value = None
if (
@@ -1425,7 +1419,8 @@ def _missing_(cls, value):
value = all_bits + 1 + value
# get members and unknown
unknown = value & ~flag_mask
- member_value = value & flag_mask
+ aliases = value & ~singles_mask
+ member_value = value & singles_mask
if unknown and cls._boundary_ is not KEEP:
raise ValueError(
'%s(%r) --> unknown values %r [%s]'
@@ -1439,11 +1434,25 @@ def _missing_(cls, value):
pseudo_member = cls._member_type_.__new__(cls, value)
if not hasattr(pseudo_member, '_value_'):
pseudo_member._value_ = value
- if member_value:
- pseudo_member._name_ = '|'.join([
- m._name_ for m in cls._iter_member_(member_value)
- ])
- if unknown:
+ if member_value or aliases:
+ members = []
+ combined_value = 0
+ for m in cls._iter_member_(member_value):
+ members.append(m)
+ combined_value |= m._value_
+ if aliases:
+ value = member_value | aliases
+ for n, pm in cls._member_map_.items():
+ if pm not in members and pm._value_ and pm._value_ & value == pm._value_:
+ members.append(pm)
+ combined_value |= pm._value_
+ unknown = value ^ combined_value
+ pseudo_member._name_ = '|'.join([m._name_ for m in members])
+ if not combined_value:
+ pseudo_member._name_ = None
+ elif unknown and cls._boundary_ is STRICT:
+ raise ValueError('%r: no members with value %r' % (cls, unknown))
+ elif unknown:
pseudo_member._name_ += '|%s' % cls._numeric_repr_(unknown)
else:
pseudo_member._name_ = None
@@ -1675,6 +1684,7 @@ def convert_class(cls):
body['_boundary_'] = boundary or etype._boundary_
body['_flag_mask_'] = None
body['_all_bits_'] = None
+ body['_singles_mask_'] = None
body['_inverted_'] = None
body['__or__'] = Flag.__or__
body['__xor__'] = Flag.__xor__
@@ -1750,7 +1760,8 @@ def convert_class(cls):
else:
multi_bits |= value
gnv_last_values.append(value)
- enum_class._flag_mask_ = single_bits
+ enum_class._flag_mask_ = single_bits | multi_bits
+ enum_class._singles_mask_ = single_bits
enum_class._all_bits_ = 2 ** ((single_bits|multi_bits).bit_length()) - 1
# set correct __iter__
member_list = [m._value_ for m in enum_class]
diff --git a/Lib/test/test_enum.py b/Lib/test/test_enum.py
index e4151bf9e6d9..89294e95df2a 100644
--- a/Lib/test/test_enum.py
+++ b/Lib/test/test_enum.py
@@ -2873,6 +2873,8 @@ def __new__(cls, c):
#
a = ord('a')
#
+ self.assertEqual(FlagFromChar._all_bits_, 316912650057057350374175801343)
+ self.assertEqual(FlagFromChar._flag_mask_, 158456325028528675187087900672)
self.assertEqual(FlagFromChar.a, 158456325028528675187087900672)
self.assertEqual(FlagFromChar.a|1, 158456325028528675187087900673)
#
@@ -2887,6 +2889,8 @@ def __new__(cls, c):
a = ord('a')
z = 1
#
+ self.assertEqual(FlagFromChar._all_bits_, 316912650057057350374175801343)
+ self.assertEqual(FlagFromChar._flag_mask_, 158456325028528675187087900674)
self.assertEqual(FlagFromChar.a.value, 158456325028528675187087900672)
self.assertEqual((FlagFromChar.a|FlagFromChar.z).value, 158456325028528675187087900674)
#
@@ -2900,6 +2904,8 @@ def __new__(cls, c):
#
a = ord('a')
#
+ self.assertEqual(FlagFromChar._all_bits_, 316912650057057350374175801343)
+ self.assertEqual(FlagFromChar._flag_mask_, 158456325028528675187087900672)
self.assertEqual(FlagFromChar.a, 158456325028528675187087900672)
self.assertEqual(FlagFromChar.a|1, 158456325028528675187087900673)
@@ -3077,18 +3083,18 @@ def test_bool(self):
self.assertEqual(bool(f.value), bool(f))
def test_boundary(self):
- self.assertIs(enum.Flag._boundary_, CONFORM)
- class Iron(Flag, boundary=STRICT):
+ self.assertIs(enum.Flag._boundary_, STRICT)
+ class Iron(Flag, boundary=CONFORM):
ONE = 1
TWO = 2
EIGHT = 8
- self.assertIs(Iron._boundary_, STRICT)
+ self.assertIs(Iron._boundary_, CONFORM)
#
- class Water(Flag, boundary=CONFORM):
+ class Water(Flag, boundary=STRICT):
ONE = 1
TWO = 2
EIGHT = 8
- self.assertIs(Water._boundary_, CONFORM)
+ self.assertIs(Water._boundary_, STRICT)
#
class Space(Flag, boundary=EJECT):
ONE = 1
@@ -3101,10 +3107,10 @@ class Bizarre(Flag, boundary=KEEP):
c = 4
d = 6
#
- self.assertRaisesRegex(ValueError, 'invalid value 7', Iron, 7)
+ self.assertRaisesRegex(ValueError, 'invalid value 7', Water, 7)
#
- self.assertIs(Water(7), Water.ONE|Water.TWO)
- self.assertIs(Water(~9), Water.TWO)
+ self.assertIs(Iron(7), Iron.ONE|Iron.TWO)
+ self.assertIs(Iron(~9), Iron.TWO)
#
self.assertEqual(Space(7), 7)
self.assertTrue(type(Space(7)) is int)
@@ -3112,6 +3118,31 @@ class Bizarre(Flag, boundary=KEEP):
self.assertEqual(list(Bizarre), [Bizarre.c])
self.assertIs(Bizarre(3), Bizarre.b)
self.assertIs(Bizarre(6), Bizarre.d)
+ #
+ class SkipFlag(enum.Flag):
+ A = 1
+ B = 2
+ C = 4 | B
+ #
+ self.assertTrue(SkipFlag.C in (SkipFlag.A|SkipFlag.C))
+ self.assertRaisesRegex(ValueError, 'SkipFlag.. invalid value 42', SkipFlag, 42)
+ #
+ class SkipIntFlag(enum.IntFlag):
+ A = 1
+ B = 2
+ C = 4 | B
+ #
+ self.assertTrue(SkipIntFlag.C in (SkipIntFlag.A|SkipIntFlag.C))
+ self.assertEqual(SkipIntFlag(42).value, 42)
+ #
+ class MethodHint(Flag):
+ HiddenText = 0x10
+ DigitsOnly = 0x01
+ LettersOnly = 0x02
+ OnlyMask = 0x0f
+ #
+ self.assertEqual(str(MethodHint.HiddenText|MethodHint.OnlyMask), 'MethodHint.HiddenText|DigitsOnly|LettersOnly|OnlyMask')
+
def test_iter(self):
Color = self.Color
diff --git a/Misc/NEWS.d/next/Library/2023-04-12-17-59-55.gh-issue-103365.UBEE0U.rst b/Misc/NEWS.d/next/Library/2023-04-12-17-59-55.gh-issue-103365.UBEE0U.rst
new file mode 100644
index 000000000000..4d69f6f6fff7
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-04-12-17-59-55.gh-issue-103365.UBEE0U.rst
@@ -0,0 +1 @@
+Set default Flag boundary to ``STRICT`` and fix bitwise operations.
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