issue23591: add Flags, IntFlags, and tests

2 files changed, 668 insertions, 11 deletions

diff --git a/Lib/enum.py b/Lib/enum.py
index e7889a8..e89c17d 100644
--- a/Lib/enum.py
+++ b/Lib/enum.py
@@ -1,5 +1,7 @@
 import sys
 from types import MappingProxyType, DynamicClassAttribute
+from functools import reduce
+from operator import or_ as _or_
 
 # try _collections first to reduce startup cost
 try:
@@ -8,7 +10,7 @@ except ImportError:
     from collections import OrderedDict
 
 
-__all__ = ['EnumMeta', 'Enum', 'IntEnum', 'unique']
+__all__ = ['EnumMeta', 'Enum', 'IntEnum', 'Flags', 'IntFlags', 'unique']
 
 
 def _is_descriptor(obj):
@@ -64,7 +66,10 @@ class _EnumDict(dict):
 
         """
         if _is_sunder(key):
-            if key not in ('_order_', ):
+            if key not in (
+                    '_order_', '_create_pseudo_member_', '_decompose_',
+                    '_generate_next_value_', '_missing_',
+                    ):
                 raise ValueError('_names_ are reserved for future Enum use')
         elif _is_dunder(key):
             if key == '__order__':
@@ -75,7 +80,7 @@ class _EnumDict(dict):
         elif not _is_descriptor(value):
             if key in self:
                 # enum overwriting a descriptor?
-                raise TypeError('Key already defined as: %r' % self[key])
+                raise TypeError('%r already defined as: %r' % (key, self[key]))
             self._member_names.append(key)
         super().__setitem__(key, value)
 
@@ -91,9 +96,15 @@ class EnumMeta(type):
     """Metaclass for Enum"""
     @classmethod
     def __prepare__(metacls, cls, bases):
-        return _EnumDict()
+        # create the namespace dict
+        enum_dict = _EnumDict()
+        # inherit previous flags and _generate_next_value_ function
+        member_type, first_enum = metacls._get_mixins_(bases)
+        if first_enum is not None:
+            enum_dict['_generate_next_value_'] = getattr(first_enum, '_generate_next_value_', None)
+        return enum_dict
 
-    def __new__(metacls, cls, bases, classdict):
+    def __new__(metacls, cls, bases, classdict, **kwds):
         # an Enum class is final once enumeration items have been defined; it
         # cannot be mixed with other types (int, float, etc.) if it has an
         # inherited __new__ unless a new __new__ is defined (or the resulting
@@ -104,7 +115,7 @@ class EnumMeta(type):
 
         # save enum items into separate mapping so they don't get baked into
         # the new class
-        members = {k: classdict[k] for k in classdict._member_names}
+        enum_members = {k: classdict[k] for k in classdict._member_names}
         for name in classdict._member_names:
             del classdict[name]
 
@@ -112,7 +123,7 @@ class EnumMeta(type):
         _order_ = classdict.pop('_order_', None)
 
         # check for illegal enum names (any others?)
-        invalid_names = set(members) & {'mro', }
+        invalid_names = set(enum_members) & {'mro', }
         if invalid_names:
             raise ValueError('Invalid enum member name: {0}'.format(
                 ','.join(invalid_names)))
@@ -156,7 +167,7 @@ class EnumMeta(type):
         # a custom __new__ is doing something funky with the values -- such as
         # auto-numbering ;)
         for member_name in classdict._member_names:
-            value = members[member_name]
+            value = enum_members[member_name]
             if not isinstance(value, tuple):
                 args = (value, )
             else:
@@ -170,7 +181,10 @@ class EnumMeta(type):
             else:
                 enum_member = __new__(enum_class, *args)
                 if not hasattr(enum_member, '_value_'):
-                    enum_member._value_ = member_type(*args)
+                    if member_type is object:
+                        enum_member._value_ = value
+                    else:
+                        enum_member._value_ = member_type(*args)
             value = enum_member._value_
             enum_member._name_ = member_name
             enum_member.__objclass__ = enum_class
@@ -344,13 +358,18 @@ class EnumMeta(type):
         """
         metacls = cls.__class__
         bases = (cls, ) if type is None else (type, cls)
+        _, first_enum = cls._get_mixins_(bases)
         classdict = metacls.__prepare__(class_name, bases)
 
         # special processing needed for names?
         if isinstance(names, str):
             names = names.replace(',', ' ').split()
         if isinstance(names, (tuple, list)) and isinstance(names[0], str):
-            names = [(e, i) for (i, e) in enumerate(names, start)]
+            original_names, names = names, []
+            last_value = None
+            for count, name in enumerate(original_names):
+                last_value = first_enum._generate_next_value_(name, start, count, last_value)
+                names.append((name, last_value))
 
         # Here, names is either an iterable of (name, value) or a mapping.
         for item in names:
@@ -492,6 +511,16 @@ class Enum(metaclass=EnumMeta):
             for member in cls._member_map_.values():
                 if member._value_ == value:
                     return member
+        # still not found -- try _missing_ hook
+        return cls._missing_(value)
+
+    @staticmethod
+    def _generate_next_value_(name, start, count, last_value):
+        if not count:
+            return start
+        return last_value + 1
+    @classmethod
+    def _missing_(cls, value):
         raise ValueError("%r is not a valid %s" % (value, cls.__name__))
 
     def __repr__(self):
@@ -585,6 +614,184 @@ class IntEnum(int, Enum):
 def _reduce_ex_by_name(self, proto):
     return self.name
 
+class Flags(Enum):
+    """Support for flags"""
+    @staticmethod
+    def _generate_next_value_(name, start, count, last_value):
+        """
+        Generate the next value when not given.
+
+        name: the name of the member
+        start: the initital start value or None
+        count: the number of existing members
+        last_value: the last value assigned or None
+        """
+        if not count:
+            return start if start is not None else 1
+        high_bit = _high_bit(last_value)
+        return 2 ** (high_bit+1)
+
+    @classmethod
+    def _missing_(cls, value):
+        original_value = value
+        if value < 0:
+            value = ~value
+        possible_member = cls._create_pseudo_member_(value)
+        for member in possible_member._decompose_():
+            if member._name_ is None and member._value_ != 0:
+                raise ValueError('%r is not a valid %s' % (original_value, cls.__name__))
+        if original_value < 0:
+            possible_member = ~possible_member
+        return possible_member
+
+    @classmethod
+    def _create_pseudo_member_(cls, value):
+        pseudo_member = cls._value2member_map_.get(value, None)
+        if pseudo_member is None:
+            # construct a non-singleton enum pseudo-member
+            pseudo_member = object.__new__(cls)
+            pseudo_member._name_ = None
+            pseudo_member._value_ = value
+            cls._value2member_map_[value] = pseudo_member
+        return pseudo_member
+
+    def _decompose_(self):
+        """Extract all members from the value."""
+        value = self._value_
+        members = []
+        cls = self.__class__
+        for member in sorted(cls, key=lambda m: m._value_, reverse=True):
+            while _high_bit(value) > _high_bit(member._value_):
+                unknown = self._create_pseudo_member_(2 ** _high_bit(value))
+                members.append(unknown)
+                value &= ~unknown._value_
+            if (
+                    (value & member._value_ == member._value_)
+                    and (member._value_ or not members)
+                    ):
+                value &= ~member._value_
+                members.append(member)
+        if not members or value:
+            members.append(self._create_pseudo_member_(value))
+        members = list(members)
+        return members
+
+    def __contains__(self, other):
+        if not isinstance(other, self.__class__):
+            return NotImplemented
+        return other._value_ & self._value_ == other._value_
+
+    def __iter__(self):
+        if self.value == 0:
+            return iter([])
+        else:
+            return iter(self._decompose_())
+
+    def __repr__(self):
+        cls = self.__class__
+        if self._name_ is not None:
+            return '<%s.%s: %r>' % (cls.__name__, self._name_, self._value_)
+        members = self._decompose_()
+        if len(members) == 1 and members[0]._name_ is None:
+            return '<%s: %r>' % (cls.__name__, members[0]._value_)
+        else:
+            return '<%s.%s: %r>' % (
+                    cls.__name__,
+                    '|'.join([str(m._name_ or m._value_) for m in members]),
+                    self._value_,
+                    )
+
+    def __str__(self):
+        cls = self.__class__
+        if self._name_ is not None:
+            return '%s.%s' % (cls.__name__, self._name_)
+        members = self._decompose_()
+        if len(members) == 1 and members[0]._name_ is None:
+            return '%s.%r' % (cls.__name__, members[0]._value_)
+        else:
+            return '%s.%s' % (
+                    cls.__name__,
+                    '|'.join([str(m._name_ or m._value_) for m in members]),
+                    )
+
+    def __or__(self, other):
+        if not isinstance(other, self.__class__):
+            return NotImplemented
+        return self.__class__(self._value_ | other._value_)
+
+    def __and__(self, other):
+        if not isinstance(other, self.__class__):
+            return NotImplemented
+        return self.__class__(self._value_ & other._value_)
+
+    def __xor__(self, other):
+        if not isinstance(other, self.__class__):
+            return NotImplemented
+        return self.__class__(self._value_ ^ other._value_)
+
+    def __invert__(self):
+        members = self._decompose_()
+        inverted_members = [m for m in self.__class__ if m not in members and not m._value_ & self._value_]
+        inverted = reduce(_or_, inverted_members, self.__class__(0))
+        return self.__class__(inverted)
+
+
+class IntFlags(int, Flags):
+    """Support for integer-based Flags"""
+
+    @classmethod
+    def _create_pseudo_member_(cls, value):
+        pseudo_member = cls._value2member_map_.get(value, None)
+        if pseudo_member is None:
+            # construct a non-singleton enum pseudo-member
+            pseudo_member = int.__new__(cls, value)
+            pseudo_member._name_ = None
+            pseudo_member._value_ = value
+            cls._value2member_map_[value] = pseudo_member
+        return pseudo_member
+
+    @classmethod
+    def _missing_(cls, value):
+        possible_member = cls._create_pseudo_member_(value)
+        return possible_member
+
+    def __or__(self, other):
+        if not isinstance(other, (self.__class__, int)):
+            return NotImplemented
+        return self.__class__(self._value_ | self.__class__(other)._value_)
+
+    def __and__(self, other):
+        if not isinstance(other, (self.__class__, int)):
+            return NotImplemented
+        return self.__class__(self._value_ & self.__class__(other)._value_)
+
+    def __xor__(self, other):
+        if not isinstance(other, (self.__class__, int)):
+            return NotImplemented
+        return self.__class__(self._value_ ^ self.__class__(other)._value_)
+
+    __ror__ = __or__
+    __rand__ = __and__
+    __rxor__ = __xor__
+
+    def __invert__(self):
+        # members = self._decompose_()
+        # inverted_members = [m for m in self.__class__ if m not in members and not m._value_ & self._value_]
+        # inverted = reduce(_or_, inverted_members, self.__class__(0))
+        return self.__class__(~self._value_)
+
+
+
+
+def _high_bit(value):
+    """return the highest bit set in value"""
+    bit = 0
+    while 'looking for the highest bit':
+        limit = 2 ** bit
+        if limit > value:
+            return bit - 1
+        bit += 1
+
 def unique(enumeration):
     """Class decorator for enumerations ensuring unique member values."""
     duplicates = []
diff --git a/Lib/test/test_enum.py b/Lib/test/test_enum.py
index 2d4519e..1831895 100644
--- a/Lib/test/test_enum.py
+++ b/Lib/test/test_enum.py
@@ -3,7 +3,7 @@ import inspect
 import pydoc
 import unittest
 from collections import OrderedDict
-from enum import Enum, IntEnum, EnumMeta, unique
+from enum import Enum, IntEnum, EnumMeta, Flags, IntFlags, unique
 from io import StringIO
 from pickle import dumps, loads, PicklingError, HIGHEST_PROTOCOL
 from test import support
@@ -1633,6 +1633,456 @@ class TestOrder(unittest.TestCase):
                 verde = green
 
 
+class TestFlags(unittest.TestCase):
+    """Tests of the Flags."""
+
+    class Perm(Flags):
+        R, W, X = 4, 2, 1
+
+    class Open(Flags):
+        RO = 0
+        WO = 1
+        RW = 2
+        AC = 3
+        CE = 1<<19
+
+    def test_str(self):
+        Perm = self.Perm
+        self.assertEqual(str(Perm.R), 'Perm.R')
+        self.assertEqual(str(Perm.W), 'Perm.W')
+        self.assertEqual(str(Perm.X), 'Perm.X')
+        self.assertEqual(str(Perm.R | Perm.W), 'Perm.R|W')
+        self.assertEqual(str(Perm.R | Perm.W | Perm.X), 'Perm.R|W|X')
+        self.assertEqual(str(Perm(0)), 'Perm.0')
+        self.assertEqual(str(~Perm.R), 'Perm.W|X')
+        self.assertEqual(str(~Perm.W), 'Perm.R|X')
+        self.assertEqual(str(~Perm.X), 'Perm.R|W')
+        self.assertEqual(str(~(Perm.R | Perm.W)), 'Perm.X')
+        self.assertEqual(str(~(Perm.R | Perm.W | Perm.X)), 'Perm.0')
+        self.assertEqual(str(Perm(~0)), 'Perm.R|W|X')
+
+        Open = self.Open
+        self.assertEqual(str(Open.RO), 'Open.RO')
+        self.assertEqual(str(Open.WO), 'Open.WO')
+        self.assertEqual(str(Open.AC), 'Open.AC')
+        self.assertEqual(str(Open.RO | Open.CE), 'Open.CE')
+        self.assertEqual(str(Open.WO | Open.CE), 'Open.CE|WO')
+        self.assertEqual(str(~Open.RO), 'Open.CE|AC')
+        self.assertEqual(str(~Open.WO), 'Open.CE|RW')
+        self.assertEqual(str(~Open.AC), 'Open.CE')
+        self.assertEqual(str(~(Open.RO | Open.CE)), 'Open.AC')
+        self.assertEqual(str(~(Open.WO | Open.CE)), 'Open.RW')
+
+    def test_repr(self):
+        Perm = self.Perm
+        self.assertEqual(repr(Perm.R), '<Perm.R: 4>')
+        self.assertEqual(repr(Perm.W), '<Perm.W: 2>')
+        self.assertEqual(repr(Perm.X), '<Perm.X: 1>')
+        self.assertEqual(repr(Perm.R | Perm.W), '<Perm.R|W: 6>')
+        self.assertEqual(repr(Perm.R | Perm.W | Perm.X), '<Perm.R|W|X: 7>')
+        self.assertEqual(repr(Perm(0)), '<Perm: 0>')
+        self.assertEqual(repr(~Perm.R), '<Perm.W|X: 3>')
+        self.assertEqual(repr(~Perm.W), '<Perm.R|X: 5>')
+        self.assertEqual(repr(~Perm.X), '<Perm.R|W: 6>')
+        self.assertEqual(repr(~(Perm.R | Perm.W)), '<Perm.X: 1>')
+        self.assertEqual(repr(~(Perm.R | Perm.W | Perm.X)), '<Perm: 0>')
+        self.assertEqual(repr(Perm(~0)), '<Perm.R|W|X: 7>')
+
+        Open = self.Open
+        self.assertEqual(repr(Open.RO), '<Open.RO: 0>')
+        self.assertEqual(repr(Open.WO), '<Open.WO: 1>')
+        self.assertEqual(repr(Open.AC), '<Open.AC: 3>')
+        self.assertEqual(repr(Open.RO | Open.CE), '<Open.CE: 524288>')
+        self.assertEqual(repr(Open.WO | Open.CE), '<Open.CE|WO: 524289>')
+        self.assertEqual(repr(~Open.RO), '<Open.CE|AC: 524291>')
+        self.assertEqual(repr(~Open.WO), '<Open.CE|RW: 524290>')
+        self.assertEqual(repr(~Open.AC), '<Open.CE: 524288>')
+        self.assertEqual(repr(~(Open.RO | Open.CE)), '<Open.AC: 3>')
+        self.assertEqual(repr(~(Open.WO | Open.CE)), '<Open.RW: 2>')
+
+    def test_or(self):
+        Perm = self.Perm
+        for i in Perm:
+            for j in Perm:
+                self.assertEqual((i | j), Perm(i.value | j.value))
+                self.assertEqual((i | j).value, i.value | j.value)
+                self.assertIs(type(i | j), Perm)
+        for i in Perm:
+            self.assertIs(i | i, i)
+        Open = self.Open
+        self.assertIs(Open.RO | Open.CE, Open.CE)
+
+    def test_and(self):
+        Perm = self.Perm
+        RW = Perm.R | Perm.W
+        RX = Perm.R | Perm.X
+        WX = Perm.W | Perm.X
+        RWX = Perm.R | Perm.W | Perm.X
+        values = list(Perm) + [RW, RX, WX, RWX, Perm(0)]
+        for i in values:
+            for j in values:
+                self.assertEqual((i & j).value, i.value & j.value)
+                self.assertIs(type(i & j), Perm)
+        for i in Perm:
+            self.assertIs(i & i, i)
+            self.assertIs(i & RWX, i)
+            self.assertIs(RWX & i, i)
+        Open = self.Open
+        self.assertIs(Open.RO & Open.CE, Open.RO)
+
+    def test_xor(self):
+        Perm = self.Perm
+        for i in Perm:
+            for j in Perm:
+                self.assertEqual((i ^ j).value, i.value ^ j.value)
+                self.assertIs(type(i ^ j), Perm)
+        for i in Perm:
+            self.assertIs(i ^ Perm(0), i)
+            self.assertIs(Perm(0) ^ i, i)
+        Open = self.Open
+        self.assertIs(Open.RO ^ Open.CE, Open.CE)
+        self.assertIs(Open.CE ^ Open.CE, Open.RO)
+
+    def test_invert(self):
+        Perm = self.Perm
+        RW = Perm.R | Perm.W
+        RX = Perm.R | Perm.X
+        WX = Perm.W | Perm.X
+        RWX = Perm.R | Perm.W | Perm.X
+        values = list(Perm) + [RW, RX, WX, RWX, Perm(0)]
+        for i in values:
+            self.assertIs(type(~i), Perm)
+            self.assertEqual(~~i, i)
+        for i in Perm:
+            self.assertIs(~~i, i)
+        Open = self.Open
+        self.assertIs(Open.WO & ~Open.WO, Open.RO)
+        self.assertIs((Open.WO|Open.CE) & ~Open.WO, Open.CE)
+
+    def test_programatic_function_string(self):
+        Perm = Flags('Perm', 'R W X')
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 1<<i
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+    def test_programatic_function_string_with_start(self):
+        Perm = Flags('Perm', 'R W X', start=8)
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 8<<i
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+    def test_programatic_function_string_list(self):
+        Perm = Flags('Perm', ['R', 'W', 'X'])
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 1<<i
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+    def test_programatic_function_iterable(self):
+        Perm = Flags('Perm', (('R', 2), ('W', 8), ('X', 32)))
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 1<<(2*i+1)
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+    def test_programatic_function_from_dict(self):
+        Perm = Flags('Perm', OrderedDict((('R', 2), ('W', 8), ('X', 32))))
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 1<<(2*i+1)
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+
+class TestIntFlags(unittest.TestCase):
+    """Tests of the IntFlags."""
+
+    class Perm(IntFlags):
+        X = 1 << 0
+        W = 1 << 1
+        R = 1 << 2
+
+    class Open(IntFlags):
+        RO = 0
+        WO = 1
+        RW = 2
+        AC = 3
+        CE = 1<<19
+
+    def test_str(self):
+        Perm = self.Perm
+        self.assertEqual(str(Perm.R), 'Perm.R')
+        self.assertEqual(str(Perm.W), 'Perm.W')
+        self.assertEqual(str(Perm.X), 'Perm.X')
+        self.assertEqual(str(Perm.R | Perm.W), 'Perm.R|W')
+        self.assertEqual(str(Perm.R | Perm.W | Perm.X), 'Perm.R|W|X')
+        self.assertEqual(str(Perm.R | 8), 'Perm.8|R')
+        self.assertEqual(str(Perm(0)), 'Perm.0')
+        self.assertEqual(str(Perm(8)), 'Perm.8')
+        self.assertEqual(str(~Perm.R), 'Perm.W|X|-8')
+        self.assertEqual(str(~Perm.W), 'Perm.R|X|-8')
+        self.assertEqual(str(~Perm.X), 'Perm.R|W|-8')
+        self.assertEqual(str(~(Perm.R | Perm.W)), 'Perm.X|-8')
+        self.assertEqual(str(~(Perm.R | Perm.W | Perm.X)), 'Perm.-8')
+        self.assertEqual(str(~(Perm.R | 8)), 'Perm.W|X|-16')
+        self.assertEqual(str(Perm(~0)), 'Perm.R|W|X|-8')
+        self.assertEqual(str(Perm(~8)), 'Perm.R|W|X|-16')
+
+        Open = self.Open
+        self.assertEqual(str(Open.RO), 'Open.RO')
+        self.assertEqual(str(Open.WO), 'Open.WO')
+        self.assertEqual(str(Open.AC), 'Open.AC')
+        self.assertEqual(str(Open.RO | Open.CE), 'Open.CE')
+        self.assertEqual(str(Open.WO | Open.CE), 'Open.CE|WO')
+        self.assertEqual(str(Open(4)), 'Open.4')
+        self.assertEqual(str(~Open.RO), 'Open.CE|AC|-524292')
+        self.assertEqual(str(~Open.WO), 'Open.CE|RW|-524292')
+        self.assertEqual(str(~Open.AC), 'Open.CE|-524292')
+        self.assertEqual(str(~(Open.RO | Open.CE)), 'Open.AC|-524292')
+        self.assertEqual(str(~(Open.WO | Open.CE)), 'Open.RW|-524292')
+        self.assertEqual(str(Open(~4)), 'Open.CE|AC|-524296')
+
+    def test_repr(self):
+        Perm = self.Perm
+        self.assertEqual(repr(Perm.R), '<Perm.R: 4>')
+        self.assertEqual(repr(Perm.W), '<Perm.W: 2>')
+        self.assertEqual(repr(Perm.X), '<Perm.X: 1>')
+        self.assertEqual(repr(Perm.R | Perm.W), '<Perm.R|W: 6>')
+        self.assertEqual(repr(Perm.R | Perm.W | Perm.X), '<Perm.R|W|X: 7>')
+        self.assertEqual(repr(Perm.R | 8), '<Perm.8|R: 12>')
+        self.assertEqual(repr(Perm(0)), '<Perm: 0>')
+        self.assertEqual(repr(Perm(8)), '<Perm: 8>')
+        self.assertEqual(repr(~Perm.R), '<Perm.W|X|-8: -5>')
+        self.assertEqual(repr(~Perm.W), '<Perm.R|X|-8: -3>')
+        self.assertEqual(repr(~Perm.X), '<Perm.R|W|-8: -2>')
+        self.assertEqual(repr(~(Perm.R | Perm.W)), '<Perm.X|-8: -7>')
+        self.assertEqual(repr(~(Perm.R | Perm.W | Perm.X)), '<Perm: -8>')
+        self.assertEqual(repr(~(Perm.R | 8)), '<Perm.W|X|-16: -13>')
+        self.assertEqual(repr(Perm(~0)), '<Perm.R|W|X|-8: -1>')
+        self.assertEqual(repr(Perm(~8)), '<Perm.R|W|X|-16: -9>')
+
+        Open = self.Open
+        self.assertEqual(repr(Open.RO), '<Open.RO: 0>')
+        self.assertEqual(repr(Open.WO), '<Open.WO: 1>')
+        self.assertEqual(repr(Open.AC), '<Open.AC: 3>')
+        self.assertEqual(repr(Open.RO | Open.CE), '<Open.CE: 524288>')
+        self.assertEqual(repr(Open.WO | Open.CE), '<Open.CE|WO: 524289>')
+        self.assertEqual(repr(Open(4)), '<Open: 4>')
+        self.assertEqual(repr(~Open.RO), '<Open.CE|AC|-524292: -1>')
+        self.assertEqual(repr(~Open.WO), '<Open.CE|RW|-524292: -2>')
+        self.assertEqual(repr(~Open.AC), '<Open.CE|-524292: -4>')
+        self.assertEqual(repr(~(Open.RO | Open.CE)), '<Open.AC|-524292: -524289>')
+        self.assertEqual(repr(~(Open.WO | Open.CE)), '<Open.RW|-524292: -524290>')
+        self.assertEqual(repr(Open(~4)), '<Open.CE|AC|-524296: -5>')
+
+    def test_or(self):
+        Perm = self.Perm
+        for i in Perm:
+            for j in Perm:
+                self.assertEqual(i | j, i.value | j.value)
+                self.assertEqual((i | j).value, i.value | j.value)
+                self.assertIs(type(i | j), Perm)
+            for j in range(8):
+                self.assertEqual(i | j, i.value | j)
+                self.assertEqual((i | j).value, i.value | j)
+                self.assertIs(type(i | j), Perm)
+                self.assertEqual(j | i, j | i.value)
+                self.assertEqual((j | i).value, j | i.value)
+                self.assertIs(type(j | i), Perm)
+        for i in Perm:
+            self.assertIs(i | i, i)
+            self.assertIs(i | 0, i)
+            self.assertIs(0 | i, i)
+        Open = self.Open
+        self.assertIs(Open.RO | Open.CE, Open.CE)
+
+    def test_and(self):
+        Perm = self.Perm
+        RW = Perm.R | Perm.W
+        RX = Perm.R | Perm.X
+        WX = Perm.W | Perm.X
+        RWX = Perm.R | Perm.W | Perm.X
+        values = list(Perm) + [RW, RX, WX, RWX, Perm(0)]
+        for i in values:
+            for j in values:
+                self.assertEqual(i & j, i.value & j.value, 'i is %r, j is %r' % (i, j))
+                self.assertEqual((i & j).value, i.value & j.value, 'i is %r, j is %r' % (i, j))
+                self.assertIs(type(i & j), Perm, 'i is %r, j is %r' % (i, j))
+            for j in range(8):
+                self.assertEqual(i & j, i.value & j)
+                self.assertEqual((i & j).value, i.value & j)
+                self.assertIs(type(i & j), Perm)
+                self.assertEqual(j & i, j & i.value)
+                self.assertEqual((j & i).value, j & i.value)
+                self.assertIs(type(j & i), Perm)
+        for i in Perm:
+            self.assertIs(i & i, i)
+            self.assertIs(i & 7, i)
+            self.assertIs(7 & i, i)
+        Open = self.Open
+        self.assertIs(Open.RO & Open.CE, Open.RO)
+
+    def test_xor(self):
+        Perm = self.Perm
+        for i in Perm:
+            for j in Perm:
+                self.assertEqual(i ^ j, i.value ^ j.value)
+                self.assertEqual((i ^ j).value, i.value ^ j.value)
+                self.assertIs(type(i ^ j), Perm)
+            for j in range(8):
+                self.assertEqual(i ^ j, i.value ^ j)
+                self.assertEqual((i ^ j).value, i.value ^ j)
+                self.assertIs(type(i ^ j), Perm)
+                self.assertEqual(j ^ i, j ^ i.value)
+                self.assertEqual((j ^ i).value, j ^ i.value)
+                self.assertIs(type(j ^ i), Perm)
+        for i in Perm:
+            self.assertIs(i ^ 0, i)
+            self.assertIs(0 ^ i, i)
+        Open = self.Open
+        self.assertIs(Open.RO ^ Open.CE, Open.CE)
+        self.assertIs(Open.CE ^ Open.CE, Open.RO)
+
+    def test_invert(self):
+        Perm = self.Perm
+        RW = Perm.R | Perm.W
+        RX = Perm.R | Perm.X
+        WX = Perm.W | Perm.X
+        RWX = Perm.R | Perm.W | Perm.X
+        values = list(Perm) + [RW, RX, WX, RWX, Perm(0)]
+        for i in values:
+            self.assertEqual(~i, ~i.value)
+            self.assertEqual((~i).value, ~i.value)
+            self.assertIs(type(~i), Perm)
+            self.assertEqual(~~i, i)
+        for i in Perm:
+            self.assertIs(~~i, i)
+        Open = self.Open
+        self.assertIs(Open.WO & ~Open.WO, Open.RO)
+        self.assertIs((Open.WO|Open.CE) & ~Open.WO, Open.CE)
+
+    def test_programatic_function_string(self):
+        Perm = IntFlags('Perm', 'R W X')
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 1<<i
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e, v)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+    def test_programatic_function_string_with_start(self):
+        Perm = IntFlags('Perm', 'R W X', start=8)
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 8<<i
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e, v)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+    def test_programatic_function_string_list(self):
+        Perm = IntFlags('Perm', ['R', 'W', 'X'])
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 1<<i
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e, v)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+    def test_programatic_function_iterable(self):
+        Perm = IntFlags('Perm', (('R', 2), ('W', 8), ('X', 32)))
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 1<<(2*i+1)
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e, v)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+    def test_programatic_function_from_dict(self):
+        Perm = IntFlags('Perm', OrderedDict((('R', 2), ('W', 8), ('X', 32))))
+        lst = list(Perm)
+        self.assertEqual(len(lst), len(Perm))
+        self.assertEqual(len(Perm), 3, Perm)
+        self.assertEqual(lst, [Perm.R, Perm.W, Perm.X])
+        for i, n in enumerate('R W X'.split()):
+            v = 1<<(2*i+1)
+            e = Perm(v)
+            self.assertEqual(e.value, v)
+            self.assertEqual(type(e.value), int)
+            self.assertEqual(e, v)
+            self.assertEqual(e.name, n)
+            self.assertIn(e, Perm)
+            self.assertIs(type(e), Perm)
+
+
 class TestUnique(unittest.TestCase):
 
     def test_unique_clean(self):