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Diffstat (limited to 'modules/language/python/module/enum.py')
| -rw-r--r-- | modules/language/python/module/enum.py | 876 |
1 files changed, 876 insertions, 0 deletions
diff --git a/modules/language/python/module/enum.py b/modules/language/python/module/enum.py new file mode 100644 index 0000000..4f388ad --- /dev/null +++ b/modules/language/python/module/enum.py @@ -0,0 +1,876 @@ +module(enum) ## needed in guile atm + +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: + from _collections import OrderedDict +except ImportError: + from collections import OrderedDict + + +__all__ = [ + 'EnumMeta', + 'Enum', 'IntEnum', 'Flag', 'IntFlag', + 'auto', 'unique', + ] + + +def _is_descriptor(obj): + """Returns True if obj is a descriptor, False otherwise.""" + return ( + hasattr(obj, '__get__') or + hasattr(obj, '__set__') or + hasattr(obj, '__delete__')) + + +def _is_dunder(name): + """Returns True if a __dunder__ name, False otherwise.""" + return (name[:2] == name[-2:] == '__' and + name[2:3] != '_' and + name[-3:-2] != '_' and + len(name) > 4) + + +def _is_sunder(name): + """Returns True if a _sunder_ name, False otherwise.""" + return (name[0] == name[-1] == '_' and + name[1:2] != '_' and + name[-2:-1] != '_' and + len(name) > 2) + +def _make_class_unpicklable(cls): + """Make the given class un-picklable.""" + def _break_on_call_reduce(self, proto): + raise TypeError('%r cannot be pickled' % self) + cls.__reduce_ex__ = _break_on_call_reduce + cls.__module__ = '<unknown>' + +_auto_null = object() +class auto: + """ + Instances are replaced with an appropriate value in Enum class suites. + """ + value = _auto_null + + +class _EnumDict(dict): + """Track enum member order and ensure member names are not reused. + + EnumMeta will use the names found in self._member_names as the + enumeration member names. + + """ + def __init__(self): + super().__init__() + self._member_names = [] + self._last_values = [] + + def __setitem__(self, key, value): + """Changes anything not dundered or not a descriptor. + + If an enum member name is used twice, an error is raised; duplicate + values are not checked for. + + Single underscore (sunder) names are reserved. + + """ + if _is_sunder(key): + if key not in ( + '_order_', '_create_pseudo_member_', + '_generate_next_value_', '_missing_', + ): + raise ValueError('_names_ are reserved for future Enum use') + if key == '_generate_next_value_': + setattr(self, '_generate_next_value', value) + elif _is_dunder(key): + if key == '__order__': + key = '_order_' + elif key in self._member_names: + # descriptor overwriting an enum? + raise TypeError('Attempted to reuse key: %r' % key) + elif not _is_descriptor(value): + if key in self: + # enum overwriting a descriptor? + raise TypeError('%r already defined as: %r' % (key, self[key])) + if isinstance(value, auto): + if value.value == _auto_null: + value.value = self._generate_next_value(key, 1, len(self._member_names), self._last_values[:]) + value = value.value + self._member_names.append(key) + self._last_values.append(value) + super().__setitem__(key, value) + + +# Dummy value for Enum as EnumMeta explicitly checks for it, but of course +# until EnumMeta finishes running the first time the Enum class doesn't exist. +# This is also why there are checks in EnumMeta like `if Enum is not None` +Enum = None + + +class EnumMeta(type): + """Metaclass for Enum""" + @classmethod + def __prepare__(metacls, cls, bases): + # 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): + # 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 + # class will fail). + member_type, first_enum = metacls._get_mixins_(bases) + __new__, save_new, use_args = metacls._find_new_(classdict, member_type, + first_enum) + + # save enum items into separate mapping so they don't get baked into + # the new class + enum_members = {k: classdict[k] for k in classdict._member_names} + for name in classdict._member_names: + del classdict[name] + + # adjust the sunders + _order_ = classdict.pop('_order_', None) + + # check for illegal enum names (any others?) + invalid_names = set(enum_members) & {'mro', } + if invalid_names: + raise ValueError('Invalid enum member name: {0}'.format( + ','.join(invalid_names))) + + # create a default docstring if one has not been provided + if '__doc__' not in classdict: + classdict['__doc__'] = 'An enumeration.' + + # create our new Enum type + enum_class = super().__new__(metacls, cls, bases, classdict) + enum_class._member_names_ = [] # names in definition order + enum_class._member_map_ = OrderedDict() # name->value map + enum_class._member_type_ = member_type + + # save attributes from super classes so we know if we can take + # the shortcut of storing members in the class dict + base_attributes = {a for b in enum_class.mro() for a in b.__dict__} + + # Reverse value->name map for hashable values. + enum_class._value2member_map_ = {} + + # If a custom type is mixed into the Enum, and it does not know how + # to pickle itself, pickle.dumps will succeed but pickle.loads will + # fail. Rather than have the error show up later and possibly far + # from the source, sabotage the pickle protocol for this class so + # that pickle.dumps also fails. + # + # However, if the new class implements its own __reduce_ex__, do not + # sabotage -- it's on them to make sure it works correctly. We use + # __reduce_ex__ instead of any of the others as it is preferred by + # pickle over __reduce__, and it handles all pickle protocols. + if '__reduce_ex__' not in classdict: + if member_type is not object: + methods = ('__getnewargs_ex__', '__getnewargs__', + '__reduce_ex__', '__reduce__') + if not any(m in member_type.__dict__ for m in methods): + _make_class_unpicklable(enum_class) + + # instantiate them, checking for duplicates as we go + # we instantiate first instead of checking for duplicates first in case + # a custom __new__ is doing something funky with the values -- such as + # auto-numbering ;) + for member_name in classdict._member_names: + value = enum_members[member_name] + if not isinstance(value, tuple): + args = (value, ) + else: + args = value + if member_type is tuple: # special case for tuple enums + args = (args, ) # wrap it one more time + if not use_args: + enum_member = __new__(enum_class) + if not hasattr(enum_member, '_value_'): + enum_member._value_ = value + else: + enum_member = __new__(enum_class, *args) + if not hasattr(enum_member, '_value_'): + 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 + enum_member.__init__(*args) + # If another member with the same value was already defined, the + # new member becomes an alias to the existing one. + for name, canonical_member in enum_class._member_map_.items(): + if canonical_member._value_ == enum_member._value_: + enum_member = canonical_member + break + else: + # Aliases don't appear in member names (only in __members__). + enum_class._member_names_.append(member_name) + # performance boost for any member that would not shadow + # a DynamicClassAttribute + if member_name not in base_attributes: + setattr(enum_class, member_name, enum_member) + # now add to _member_map_ + enum_class._member_map_[member_name] = enum_member + try: + # This may fail if value is not hashable. We can't add the value + # to the map, and by-value lookups for this value will be + # linear. + enum_class._value2member_map_[value] = enum_member + except TypeError: + pass + + # double check that repr and friends are not the mixin's or various + # things break (such as pickle) + for name in ('__repr__', '__str__', '__format__', '__reduce_ex__'): + class_method = getattr(enum_class, name) + obj_method = getattr(member_type, name, None) + enum_method = getattr(first_enum, name, None) + if obj_method is not None and obj_method is class_method: + setattr(enum_class, name, enum_method) + + # replace any other __new__ with our own (as long as Enum is not None, + # anyway) -- again, this is to support pickle + if Enum is not None: + # if the user defined their own __new__, save it before it gets + # clobbered in case they subclass later + if save_new: + enum_class.__new_member__ = __new__ + enum_class.__new__ = Enum.__new__ + + # py3 support for definition order (helps keep py2/py3 code in sync) + if _order_ is not None: + if isinstance(_order_, str): + _order_ = _order_.replace(',', ' ').split() + if _order_ != enum_class._member_names_: + raise TypeError('member order does not match _order_') + + return enum_class + + def __bool__(self): + """ + classes/types should always be True. + """ + return True + + def __call__(cls, value, names=None, *, module=None, qualname=None, type=None, start=1): + """Either returns an existing member, or creates a new enum class. + + This method is used both when an enum class is given a value to match + to an enumeration member (i.e. Color(3)) and for the functional API + (i.e. Color = Enum('Color', names='RED GREEN BLUE')). + + When used for the functional API: + + `value` will be the name of the new class. + + `names` should be either a string of white-space/comma delimited names + (values will start at `start`), or an iterator/mapping of name, value pairs. + + `module` should be set to the module this class is being created in; + if it is not set, an attempt to find that module will be made, but if + it fails the class will not be picklable. + + `qualname` should be set to the actual location this class can be found + at in its module; by default it is set to the global scope. If this is + not correct, unpickling will fail in some circumstances. + + `type`, if set, will be mixed in as the first base class. + + """ + if names is None: # simple value lookup + return cls.__new__(cls, value) + # otherwise, functional API: we're creating a new Enum type + return cls._create_(value, names, module=module, qualname=qualname, type=type, start=start) + + def __contains__(cls, member): + return isinstance(member, cls) and member._name_ in cls._member_map_ + + def __delattr__(cls, attr): + # nicer error message when someone tries to delete an attribute + # (see issue19025). + if attr in cls._member_map_: + raise AttributeError( + "%s: cannot delete Enum member." % cls.__name__) + super().__delattr__(attr) + + def __dir__(self): + return (['__class__', '__doc__', '__members__', '__module__'] + + self._member_names_) + + def __getattr__(cls, name): + """Return the enum member matching `name` + + We use __getattr__ instead of descriptors or inserting into the enum + class' __dict__ in order to support `name` and `value` being both + properties for enum members (which live in the class' __dict__) and + enum members themselves. + + """ + if _is_dunder(name): + raise AttributeError(name) + try: + return cls._member_map_[name] + except KeyError: + raise AttributeError(name) from None + + def __getitem__(cls, name): + return cls._member_map_[name] + + def __iter__(cls): + return (cls._member_map_[name] for name in cls._member_names_) + + def __len__(cls): + return len(cls._member_names_) + + @property + def __members__(cls): + """Returns a mapping of member name->value. + + This mapping lists all enum members, including aliases. Note that this + is a read-only view of the internal mapping. + + """ + return MappingProxyType(cls._member_map_) + + def __repr__(cls): + return "<enum %r>" % cls.__name__ + + def __reversed__(cls): + return (cls._member_map_[name] for name in reversed(cls._member_names_)) + + def __setattr__(cls, name, value): + """Block attempts to reassign Enum members. + + A simple assignment to the class namespace only changes one of the + several possible ways to get an Enum member from the Enum class, + resulting in an inconsistent Enumeration. + + """ + member_map = cls.__dict__.get('_member_map_', {}) + if name in member_map: + raise AttributeError('Cannot reassign members.') + super().__setattr__(name, value) + + def _create_(cls, class_name, names=None, *, module=None, qualname=None, type=None, start=1): + """Convenience method to create a new Enum class. + + `names` can be: + + * A string containing member names, separated either with spaces or + commas. Values are incremented by 1 from `start`. + * An iterable of member names. Values are incremented by 1 from `start`. + * An iterable of (member name, value) pairs. + * A mapping of member name -> value pairs. + + """ + 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 names and isinstance(names[0], str): + original_names, names = names, [] + last_values = [] + for count, name in enumerate(original_names): + value = first_enum._generate_next_value_(name, start, count, last_values[:]) + last_values.append(value) + names.append((name, value)) + + # Here, names is either an iterable of (name, value) or a mapping. + for item in names: + if isinstance(item, str): + member_name, member_value = item, names[item] + else: + member_name, member_value = item + classdict[member_name] = member_value + enum_class = metacls.__new__(metacls, class_name, bases, classdict) + + # TODO: replace the frame hack if a blessed way to know the calling + # module is ever developed + if module is None: + try: + module = sys._getframe(2).f_globals['__name__'] + except (AttributeError, ValueError) as exc: + pass + if module is None: + _make_class_unpicklable(enum_class) + else: + enum_class.__module__ = module + if qualname is not None: + enum_class.__qualname__ = qualname + + return enum_class + + @staticmethod + def _get_mixins_(bases): + """Returns the type for creating enum members, and the first inherited + enum class. + + bases: the tuple of bases that was given to __new__ + + """ + if not bases: + return object, Enum + + # double check that we are not subclassing a class with existing + # enumeration members; while we're at it, see if any other data + # type has been mixed in so we can use the correct __new__ + member_type = first_enum = None + for base in bases: + if (base is not Enum and + issubclass(base, Enum) and + base._member_names_): + raise TypeError("Cannot extend enumerations") + # base is now the last base in bases + if not issubclass(base, Enum): + raise TypeError("new enumerations must be created as " + "`ClassName([mixin_type,] enum_type)`") + + # get correct mix-in type (either mix-in type of Enum subclass, or + # first base if last base is Enum) + if not issubclass(bases[0], Enum): + member_type = bases[0] # first data type + first_enum = bases[-1] # enum type + else: + for base in bases[0].__mro__: + # most common: (IntEnum, int, Enum, object) + # possible: (<Enum 'AutoIntEnum'>, <Enum 'IntEnum'>, + # <class 'int'>, <Enum 'Enum'>, + # <class 'object'>) + if issubclass(base, Enum): + if first_enum is None: + first_enum = base + else: + if member_type is None: + member_type = base + + return member_type, first_enum + + @staticmethod + def _find_new_(classdict, member_type, first_enum): + """Returns the __new__ to be used for creating the enum members. + + classdict: the class dictionary given to __new__ + member_type: the data type whose __new__ will be used by default + first_enum: enumeration to check for an overriding __new__ + + """ + # now find the correct __new__, checking to see of one was defined + # by the user; also check earlier enum classes in case a __new__ was + # saved as __new_member__ + __new__ = classdict.get('__new__', None) + + # should __new__ be saved as __new_member__ later? + save_new = __new__ is not None + + if __new__ is None: + # check all possibles for __new_member__ before falling back to + # __new__ + for method in ('__new_member__', '__new__'): + for possible in (member_type, first_enum): + target = getattr(possible, method, None) + if target not in { + None, + None.__new__, + object.__new__, + Enum.__new__, + }: + __new__ = target + break + if __new__ is not None: + break + else: + __new__ = object.__new__ + + # if a non-object.__new__ is used then whatever value/tuple was + # assigned to the enum member name will be passed to __new__ and to the + # new enum member's __init__ + if __new__ is object.__new__: + use_args = False + else: + use_args = True + + return __new__, save_new, use_args + +class Enum(metaclass=EnumMeta): + """Generic enumeration. + + Derive from this class to define new enumerations. + + """ + def __new__(cls, value): + # all enum instances are actually created during class construction + # without calling this method; this method is called by the metaclass' + # __call__ (i.e. Color(3) ), and by pickle + if type(value) is cls: + # For lookups like Color(Color.RED) + return value + # by-value search for a matching enum member + # see if it's in the reverse mapping (for hashable values) + try: + if value in cls._value2member_map_: + return cls._value2member_map_[value] + except TypeError: + # not there, now do long search -- O(n) behavior + for member in cls._member_map_.values(): + if member._value_ == value: + return member + # still not found -- try _missing_ hook + return cls._missing_(value) + + def _generate_next_value_(name, start, count, last_values): + for last_value in reversed(last_values): + try: + return last_value + 1 + except TypeError: + pass + else: + return start + + @classmethod + def _missing_(cls, value): + raise ValueError("%r is not a valid %s" % (value, cls.__name__)) + + def __repr__(self): + return "<%s.%s: %r>" % ( + self.__class__.__name__, self._name_, self._value_) + + def __str__(self): + return "%s.%s" % (self.__class__.__name__, self._name_) + + def __dir__(self): + added_behavior = [ + m + for cls in self.__class__.mro() + for m in cls.__dict__ + if m[0] != '_' and m not in self._member_map_ + ] + return (['__class__', '__doc__', '__module__'] + added_behavior) + + def __format__(self, format_spec): + # mixed-in Enums should use the mixed-in type's __format__, otherwise + # we can get strange results with the Enum name showing up instead of + # the value + + # pure Enum branch + if self._member_type_ is object: + cls = str + val = str(self) + # mix-in branch + else: + cls = self._member_type_ + val = self._value_ + return cls.__format__(val, format_spec) + + def __hash__(self): + return hash(self._name_) + + def __reduce_ex__(self, proto): + return self.__class__, (self._value_, ) + + # DynamicClassAttribute is used to provide access to the `name` and + # `value` properties of enum members while keeping some measure of + # protection from modification, while still allowing for an enumeration + # to have members named `name` and `value`. This works because enumeration + # members are not set directly on the enum class -- __getattr__ is + # used to look them up. + + @DynamicClassAttribute + def name(self): + """The name of the Enum member.""" + return self._name_ + + @DynamicClassAttribute + def value(self): + """The value of the Enum member.""" + return self._value_ + + @classmethod + def _convert(cls, name, module, filter, source=None): + """ + Create a new Enum subclass that replaces a collection of global constants + """ + # convert all constants from source (or module) that pass filter() to + # a new Enum called name, and export the enum and its members back to + # module; + # also, replace the __reduce_ex__ method so unpickling works in + # previous Python versions + module_globals = vars(sys.modules[module]) + if source: + source = vars(source) + else: + source = module_globals + # We use an OrderedDict of sorted source keys so that the + # _value2member_map is populated in the same order every time + # for a consistent reverse mapping of number to name when there + # are multiple names for the same number rather than varying + # between runs due to hash randomization of the module dictionary. + members = [ + (name, source[name]) + for name in source.keys() + if filter(name)] + try: + # sort by value + members.sort(key=lambda t: (t[1], t[0])) + except TypeError: + # unless some values aren't comparable, in which case sort by name + members.sort(key=lambda t: t[0]) + cls = cls(name, members, module=module) + cls.__reduce_ex__ = _reduce_ex_by_name + module_globals.update(cls.__members__) + module_globals[name] = cls + return cls + + +class IntEnum(int, Enum): + """Enum where members are also (and must be) ints""" + + +def _reduce_ex_by_name(self, proto): + return self.name + +class Flag(Enum): + """Support for flags""" + + def _generate_next_value_(name, start, count, last_values): + """ + 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 + for last_value in reversed(last_values): + try: + high_bit = _high_bit(last_value) + break + except Exception: + raise TypeError('Invalid Flag value: %r' % last_value) from None + 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) + if original_value < 0: + possible_member = ~possible_member + return possible_member + + @classmethod + def _create_pseudo_member_(cls, value): + """ + Create a composite member iff value contains only members. + """ + pseudo_member = cls._value2member_map_.get(value, None) + if pseudo_member is None: + # verify all bits are accounted for + _, extra_flags = _decompose(cls, value) + if extra_flags: + raise ValueError("%r is not a valid %s" % (value, cls.__name__)) + # construct a singleton enum pseudo-member + pseudo_member = object.__new__(cls) + pseudo_member._name_ = None + pseudo_member._value_ = value + # use setdefault in case another thread already created a composite + # with this value + pseudo_member = cls._value2member_map_.setdefault(value, pseudo_member) + return pseudo_member + + def __contains__(self, other): + if not isinstance(other, self.__class__): + return NotImplemented + return other._value_ & self._value_ == other._value_ + + def __repr__(self): + cls = self.__class__ + if self._name_ is not None: + return '<%s.%s: %r>' % (cls.__name__, self._name_, self._value_) + members, uncovered = _decompose(cls, self._value_) + 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, uncovered = _decompose(cls, self._value_) + 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 __bool__(self): + return bool(self._value_) + + 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, uncovered = _decompose(self.__class__, self._value_) + 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 IntFlag(int, Flag): + """Support for integer-based Flags""" + + @classmethod + def _missing_(cls, value): + if not isinstance(value, int): + raise ValueError("%r is not a valid %s" % (value, cls.__name__)) + new_member = cls._create_pseudo_member_(value) + return new_member + + @classmethod + def _create_pseudo_member_(cls, value): + pseudo_member = cls._value2member_map_.get(value, None) + if pseudo_member is None: + need_to_create = [value] + # get unaccounted for bits + _, extra_flags = _decompose(cls, value) + # timer = 10 + while extra_flags: + # timer -= 1 + bit = _high_bit(extra_flags) + flag_value = 2 ** bit + if (flag_value not in cls._value2member_map_ and + flag_value not in need_to_create + ): + need_to_create.append(flag_value) + if extra_flags == -flag_value: + extra_flags = 0 + else: + extra_flags ^= flag_value + for value in reversed(need_to_create): + # construct singleton pseudo-members + pseudo_member = int.__new__(cls, value) + pseudo_member._name_ = None + pseudo_member._value_ = value + # use setdefault in case another thread already created a composite + # with this value + pseudo_member = cls._value2member_map_.setdefault(value, pseudo_member) + return pseudo_member + + def __or__(self, other): + if not isinstance(other, (self.__class__, int)): + return NotImplemented + result = self.__class__(self._value_ | self.__class__(other)._value_) + return result + + 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): + result = self.__class__(~self._value_) + return result + + +def _high_bit(value): + """returns index of highest bit, or -1 if value is zero or negative""" + return value.bit_length() - 1 + +def unique(enumeration): + """Class decorator for enumerations ensuring unique member values.""" + duplicates = [] + for name, member in enumeration.__members__.items(): + if name != member.name: + duplicates.append((name, member.name)) + if duplicates: + alias_details = ', '.join( + ["%s -> %s" % (alias, name) for (alias, name) in duplicates]) + raise ValueError('duplicate values found in %r: %s' % + (enumeration, alias_details)) + return enumeration + +def _decompose(flag, value): + """Extract all members from the value.""" + # _decompose is only called if the value is not named + not_covered = value + negative = value < 0 + # issue29167: wrap accesses to _value2member_map_ in a list to avoid race + # conditions between iterating over it and having more psuedo- + # members added to it + if negative: + # only check for named flags + flags_to_check = [ + (m, v) + for v, m in list(flag._value2member_map_.items()) + if m.name is not None + ] + else: + # check for named flags and powers-of-two flags + flags_to_check = [ + (m, v) + for v, m in list(flag._value2member_map_.items()) + if m.name is not None or _power_of_two(v) + ] + members = [] + for member, member_value in flags_to_check: + if member_value and member_value & value == member_value: + members.append(member) + not_covered &= ~member_value + if not members and value in flag._value2member_map_: + members.append(flag._value2member_map_[value]) + members.sort(key=lambda m: m._value_, reverse=True) + if len(members) > 1 and members[0].value == value: + # we have the breakdown, don't need the value member itself + members.pop(0) + return members, not_covered + +def _power_of_two(value): + if value < 1: + return False + return value == 2 ** _high_bit(value) |