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838 lines
30 KiB
838 lines
30 KiB
6 years ago
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"""Python Enumerations"""
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import sys as _sys
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__all__ = ['Enum', 'IntEnum', 'unique']
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version = 1, 1, 6
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pyver = float('%s.%s' % _sys.version_info[:2])
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try:
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any
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except NameError:
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def any(iterable):
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for element in iterable:
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if element:
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return True
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return False
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try:
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from collections import OrderedDict
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except ImportError:
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OrderedDict = None
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try:
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basestring
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except NameError:
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# In Python 2 basestring is the ancestor of both str and unicode
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# in Python 3 it's just str, but was missing in 3.1
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basestring = str
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try:
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unicode
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except NameError:
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# In Python 3 unicode no longer exists (it's just str)
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unicode = str
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class _RouteClassAttributeToGetattr(object):
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"""Route attribute access on a class to __getattr__.
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This is a descriptor, used to define attributes that act differently when
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accessed through an instance and through a class. Instance access remains
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normal, but access to an attribute through a class will be routed to the
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class's __getattr__ method; this is done by raising AttributeError.
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"""
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def __init__(self, fget=None):
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self.fget = fget
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def __get__(self, instance, ownerclass=None):
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if instance is None:
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raise AttributeError()
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return self.fget(instance)
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def __set__(self, instance, value):
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raise AttributeError("can't set attribute")
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def __delete__(self, instance):
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raise AttributeError("can't delete attribute")
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def _is_descriptor(obj):
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"""Returns True if obj is a descriptor, False otherwise."""
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return (
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hasattr(obj, '__get__') or
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hasattr(obj, '__set__') or
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hasattr(obj, '__delete__'))
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def _is_dunder(name):
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"""Returns True if a __dunder__ name, False otherwise."""
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return (name[:2] == name[-2:] == '__' and
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name[2:3] != '_' and
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name[-3:-2] != '_' and
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len(name) > 4)
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def _is_sunder(name):
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"""Returns True if a _sunder_ name, False otherwise."""
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return (name[0] == name[-1] == '_' and
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name[1:2] != '_' and
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name[-2:-1] != '_' and
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len(name) > 2)
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def _make_class_unpicklable(cls):
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"""Make the given class un-picklable."""
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def _break_on_call_reduce(self, protocol=None):
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raise TypeError('%r cannot be pickled' % self)
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cls.__reduce_ex__ = _break_on_call_reduce
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cls.__module__ = '<unknown>'
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class _EnumDict(dict):
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"""Track enum member order and ensure member names are not reused.
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EnumMeta will use the names found in self._member_names as the
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enumeration member names.
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"""
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def __init__(self):
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super(_EnumDict, self).__init__()
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self._member_names = []
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def __setitem__(self, key, value):
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"""Changes anything not dundered or not a descriptor.
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If a descriptor is added with the same name as an enum member, the name
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is removed from _member_names (this may leave a hole in the numerical
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sequence of values).
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If an enum member name is used twice, an error is raised; duplicate
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values are not checked for.
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Single underscore (sunder) names are reserved.
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Note: in 3.x __order__ is simply discarded as a not necessary piece
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leftover from 2.x
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"""
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if pyver >= 3.0 and key in ('_order_', '__order__'):
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return
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elif key == '__order__':
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key = '_order_'
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if _is_sunder(key):
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if key != '_order_':
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raise ValueError('_names_ are reserved for future Enum use')
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elif _is_dunder(key):
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pass
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elif key in self._member_names:
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# descriptor overwriting an enum?
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raise TypeError('Attempted to reuse key: %r' % key)
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elif not _is_descriptor(value):
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if key in self:
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# enum overwriting a descriptor?
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raise TypeError('Key already defined as: %r' % self[key])
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self._member_names.append(key)
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super(_EnumDict, self).__setitem__(key, value)
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# Dummy value for Enum as EnumMeta explicity checks for it, but of course until
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# EnumMeta finishes running the first time the Enum class doesn't exist. This
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# is also why there are checks in EnumMeta like `if Enum is not None`
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Enum = None
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class EnumMeta(type):
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"""Metaclass for Enum"""
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@classmethod
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def __prepare__(metacls, cls, bases):
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return _EnumDict()
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def __new__(metacls, cls, bases, classdict):
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# an Enum class is final once enumeration items have been defined; it
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# cannot be mixed with other types (int, float, etc.) if it has an
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# inherited __new__ unless a new __new__ is defined (or the resulting
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# class will fail).
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if type(classdict) is dict:
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original_dict = classdict
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classdict = _EnumDict()
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for k, v in original_dict.items():
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classdict[k] = v
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member_type, first_enum = metacls._get_mixins_(bases)
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__new__, save_new, use_args = metacls._find_new_(classdict, member_type,
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first_enum)
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# save enum items into separate mapping so they don't get baked into
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# the new class
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members = dict((k, classdict[k]) for k in classdict._member_names)
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for name in classdict._member_names:
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del classdict[name]
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# py2 support for definition order
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_order_ = classdict.get('_order_')
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if _order_ is None:
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if pyver < 3.0:
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try:
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_order_ = [name for (name, value) in sorted(members.items(), key=lambda item: item[1])]
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except TypeError:
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_order_ = [name for name in sorted(members.keys())]
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else:
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_order_ = classdict._member_names
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else:
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del classdict['_order_']
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if pyver < 3.0:
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_order_ = _order_.replace(',', ' ').split()
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aliases = [name for name in members if name not in _order_]
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_order_ += aliases
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# check for illegal enum names (any others?)
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invalid_names = set(members) & set(['mro'])
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if invalid_names:
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raise ValueError('Invalid enum member name(s): %s' % (
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', '.join(invalid_names), ))
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# save attributes from super classes so we know if we can take
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# the shortcut of storing members in the class dict
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base_attributes = set([a for b in bases for a in b.__dict__])
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# create our new Enum type
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enum_class = super(EnumMeta, metacls).__new__(metacls, cls, bases, classdict)
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enum_class._member_names_ = [] # names in random order
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if OrderedDict is not None:
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enum_class._member_map_ = OrderedDict()
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else:
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enum_class._member_map_ = {} # name->value map
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enum_class._member_type_ = member_type
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# Reverse value->name map for hashable values.
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enum_class._value2member_map_ = {}
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# instantiate them, checking for duplicates as we go
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# we instantiate first instead of checking for duplicates first in case
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# a custom __new__ is doing something funky with the values -- such as
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# auto-numbering ;)
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if __new__ is None:
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__new__ = enum_class.__new__
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for member_name in _order_:
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value = members[member_name]
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if not isinstance(value, tuple):
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args = (value, )
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else:
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args = value
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if member_type is tuple: # special case for tuple enums
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args = (args, ) # wrap it one more time
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if not use_args or not args:
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enum_member = __new__(enum_class)
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if not hasattr(enum_member, '_value_'):
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enum_member._value_ = value
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else:
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enum_member = __new__(enum_class, *args)
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if not hasattr(enum_member, '_value_'):
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enum_member._value_ = member_type(*args)
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value = enum_member._value_
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enum_member._name_ = member_name
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enum_member.__objclass__ = enum_class
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enum_member.__init__(*args)
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# If another member with the same value was already defined, the
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# new member becomes an alias to the existing one.
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for name, canonical_member in enum_class._member_map_.items():
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if canonical_member.value == enum_member._value_:
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enum_member = canonical_member
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break
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else:
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# Aliases don't appear in member names (only in __members__).
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enum_class._member_names_.append(member_name)
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# performance boost for any member that would not shadow
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# a DynamicClassAttribute (aka _RouteClassAttributeToGetattr)
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if member_name not in base_attributes:
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setattr(enum_class, member_name, enum_member)
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# now add to _member_map_
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enum_class._member_map_[member_name] = enum_member
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try:
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# This may fail if value is not hashable. We can't add the value
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# to the map, and by-value lookups for this value will be
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# linear.
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enum_class._value2member_map_[value] = enum_member
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except TypeError:
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pass
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# If a custom type is mixed into the Enum, and it does not know how
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# to pickle itself, pickle.dumps will succeed but pickle.loads will
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# fail. Rather than have the error show up later and possibly far
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# from the source, sabotage the pickle protocol for this class so
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# that pickle.dumps also fails.
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#
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# However, if the new class implements its own __reduce_ex__, do not
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# sabotage -- it's on them to make sure it works correctly. We use
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# __reduce_ex__ instead of any of the others as it is preferred by
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# pickle over __reduce__, and it handles all pickle protocols.
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unpicklable = False
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if '__reduce_ex__' not in classdict:
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if member_type is not object:
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methods = ('__getnewargs_ex__', '__getnewargs__',
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'__reduce_ex__', '__reduce__')
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if not any(m in member_type.__dict__ for m in methods):
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_make_class_unpicklable(enum_class)
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unpicklable = True
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# double check that repr and friends are not the mixin's or various
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# things break (such as pickle)
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for name in ('__repr__', '__str__', '__format__', '__reduce_ex__'):
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class_method = getattr(enum_class, name)
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obj_method = getattr(member_type, name, None)
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enum_method = getattr(first_enum, name, None)
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if name not in classdict and class_method is not enum_method:
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if name == '__reduce_ex__' and unpicklable:
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continue
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setattr(enum_class, name, enum_method)
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# method resolution and int's are not playing nice
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# Python's less than 2.6 use __cmp__
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if pyver < 2.6:
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if issubclass(enum_class, int):
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setattr(enum_class, '__cmp__', getattr(int, '__cmp__'))
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elif pyver < 3.0:
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if issubclass(enum_class, int):
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for method in (
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'__le__',
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'__lt__',
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'__gt__',
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'__ge__',
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'__eq__',
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'__ne__',
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'__hash__',
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):
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setattr(enum_class, method, getattr(int, method))
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# replace any other __new__ with our own (as long as Enum is not None,
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# anyway) -- again, this is to support pickle
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if Enum is not None:
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# if the user defined their own __new__, save it before it gets
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# clobbered in case they subclass later
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if save_new:
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setattr(enum_class, '__member_new__', enum_class.__dict__['__new__'])
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setattr(enum_class, '__new__', Enum.__dict__['__new__'])
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return enum_class
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def __bool__(cls):
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"""
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classes/types should always be True.
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"""
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return True
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def __call__(cls, value, names=None, module=None, type=None, start=1):
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"""Either returns an existing member, or creates a new enum class.
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This method is used both when an enum class is given a value to match
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to an enumeration member (i.e. Color(3)) and for the functional API
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(i.e. Color = Enum('Color', names='red green blue')).
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When used for the functional API: `module`, if set, will be stored in
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the new class' __module__ attribute; `type`, if set, will be mixed in
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as the first base class.
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Note: if `module` is not set this routine will attempt to discover the
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calling module by walking the frame stack; if this is unsuccessful
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the resulting class will not be pickleable.
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"""
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if names is None: # simple value lookup
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return cls.__new__(cls, value)
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# otherwise, functional API: we're creating a new Enum type
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return cls._create_(value, names, module=module, type=type, start=start)
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def __contains__(cls, member):
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return isinstance(member, cls) and member.name in cls._member_map_
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def __delattr__(cls, attr):
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# nicer error message when someone tries to delete an attribute
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# (see issue19025).
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if attr in cls._member_map_:
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raise AttributeError(
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"%s: cannot delete Enum member." % cls.__name__)
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super(EnumMeta, cls).__delattr__(attr)
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def __dir__(self):
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return (['__class__', '__doc__', '__members__', '__module__'] +
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self._member_names_)
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@property
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def __members__(cls):
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"""Returns a mapping of member name->value.
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This mapping lists all enum members, including aliases. Note that this
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is a copy of the internal mapping.
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"""
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return cls._member_map_.copy()
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def __getattr__(cls, name):
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"""Return the enum member matching `name`
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We use __getattr__ instead of descriptors or inserting into the enum
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class' __dict__ in order to support `name` and `value` being both
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properties for enum members (which live in the class' __dict__) and
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enum members themselves.
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"""
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if _is_dunder(name):
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raise AttributeError(name)
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try:
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return cls._member_map_[name]
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except KeyError:
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raise AttributeError(name)
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def __getitem__(cls, name):
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return cls._member_map_[name]
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def __iter__(cls):
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return (cls._member_map_[name] for name in cls._member_names_)
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def __reversed__(cls):
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return (cls._member_map_[name] for name in reversed(cls._member_names_))
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def __len__(cls):
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return len(cls._member_names_)
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__nonzero__ = __bool__
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def __repr__(cls):
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return "<enum %r>" % cls.__name__
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def __setattr__(cls, name, value):
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"""Block attempts to reassign Enum members.
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A simple assignment to the class namespace only changes one of the
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several possible ways to get an Enum member from the Enum class,
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resulting in an inconsistent Enumeration.
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"""
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member_map = cls.__dict__.get('_member_map_', {})
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if name in member_map:
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raise AttributeError('Cannot reassign members.')
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super(EnumMeta, cls).__setattr__(name, value)
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def _create_(cls, class_name, names=None, module=None, type=None, start=1):
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"""Convenience method to create a new Enum class.
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`names` can be:
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* A string containing member names, separated either with spaces or
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commas. Values are auto-numbered from 1.
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* An iterable of member names. Values are auto-numbered from 1.
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||
|
* An iterable of (member name, value) pairs.
|
||
|
* A mapping of member name -> value.
|
||
|
|
||
|
"""
|
||
|
if pyver < 3.0:
|
||
|
# if class_name is unicode, attempt a conversion to ASCII
|
||
|
if isinstance(class_name, unicode):
|
||
|
try:
|
||
|
class_name = class_name.encode('ascii')
|
||
|
except UnicodeEncodeError:
|
||
|
raise TypeError('%r is not representable in ASCII' % class_name)
|
||
|
metacls = cls.__class__
|
||
|
if type is None:
|
||
|
bases = (cls, )
|
||
|
else:
|
||
|
bases = (type, cls)
|
||
|
classdict = metacls.__prepare__(class_name, bases)
|
||
|
_order_ = []
|
||
|
|
||
|
# special processing needed for names?
|
||
|
if isinstance(names, basestring):
|
||
|
names = names.replace(',', ' ').split()
|
||
|
if isinstance(names, (tuple, list)) and isinstance(names[0], basestring):
|
||
|
names = [(e, i+start) for (i, e) in enumerate(names)]
|
||
|
|
||
|
# Here, names is either an iterable of (name, value) or a mapping.
|
||
|
item = None # in case names is empty
|
||
|
for item in names:
|
||
|
if isinstance(item, basestring):
|
||
|
member_name, member_value = item, names[item]
|
||
|
else:
|
||
|
member_name, member_value = item
|
||
|
classdict[member_name] = member_value
|
||
|
_order_.append(member_name)
|
||
|
# only set _order_ in classdict if name/value was not from a mapping
|
||
|
if not isinstance(item, basestring):
|
||
|
classdict['_order_'] = ' '.join(_order_)
|
||
|
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):
|
||
|
pass
|
||
|
if module is None:
|
||
|
_make_class_unpicklable(enum_class)
|
||
|
else:
|
||
|
enum_class.__module__ = module
|
||
|
|
||
|
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 or Enum is None:
|
||
|
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
|
||
|
|
||
|
if pyver < 3.0:
|
||
|
@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 __member_new__
|
||
|
__new__ = classdict.get('__new__', None)
|
||
|
if __new__:
|
||
|
return None, True, True # __new__, save_new, use_args
|
||
|
|
||
|
N__new__ = getattr(None, '__new__')
|
||
|
O__new__ = getattr(object, '__new__')
|
||
|
if Enum is None:
|
||
|
E__new__ = N__new__
|
||
|
else:
|
||
|
E__new__ = Enum.__dict__['__new__']
|
||
|
# check all possibles for __member_new__ before falling back to
|
||
|
# __new__
|
||
|
for method in ('__member_new__', '__new__'):
|
||
|
for possible in (member_type, first_enum):
|
||
|
try:
|
||
|
target = possible.__dict__[method]
|
||
|
except (AttributeError, KeyError):
|
||
|
target = getattr(possible, method, None)
|
||
|
if target not in [
|
||
|
None,
|
||
|
N__new__,
|
||
|
O__new__,
|
||
|
E__new__,
|
||
|
]:
|
||
|
if method == '__member_new__':
|
||
|
classdict['__new__'] = target
|
||
|
return None, False, True
|
||
|
if isinstance(target, staticmethod):
|
||
|
target = target.__get__(member_type)
|
||
|
__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__, False, use_args
|
||
|
else:
|
||
|
@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 __member_new__
|
||
|
__new__ = classdict.get('__new__', None)
|
||
|
|
||
|
# should __new__ be saved as __member_new__ later?
|
||
|
save_new = __new__ is not None
|
||
|
|
||
|
if __new__ is None:
|
||
|
# check all possibles for __member_new__ before falling back to
|
||
|
# __new__
|
||
|
for method in ('__member_new__', '__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
|
||
|
|
||
|
|
||
|
########################################################
|
||
|
# In order to support Python 2 and 3 with a single
|
||
|
# codebase we have to create the Enum methods separately
|
||
|
# and then use the `type(name, bases, dict)` method to
|
||
|
# create the class.
|
||
|
########################################################
|
||
|
temp_enum_dict = {}
|
||
|
temp_enum_dict['__doc__'] = "Generic enumeration.\n\n Derive from this class to define new enumerations.\n\n"
|
||
|
|
||
|
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)
|
||
|
value = value.value
|
||
|
#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
|
||
|
raise ValueError("%s is not a valid %s" % (value, cls.__name__))
|
||
|
temp_enum_dict['__new__'] = __new__
|
||
|
del __new__
|
||
|
|
||
|
def __repr__(self):
|
||
|
return "<%s.%s: %r>" % (
|
||
|
self.__class__.__name__, self._name_, self._value_)
|
||
|
temp_enum_dict['__repr__'] = __repr__
|
||
|
del __repr__
|
||
|
|
||
|
def __str__(self):
|
||
|
return "%s.%s" % (self.__class__.__name__, self._name_)
|
||
|
temp_enum_dict['__str__'] = __str__
|
||
|
del __str__
|
||
|
|
||
|
if pyver >= 3.0:
|
||
|
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)
|
||
|
temp_enum_dict['__dir__'] = __dir__
|
||
|
del __dir__
|
||
|
|
||
|
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)
|
||
|
temp_enum_dict['__format__'] = __format__
|
||
|
del __format__
|
||
|
|
||
|
|
||
|
####################################
|
||
|
# Python's less than 2.6 use __cmp__
|
||
|
|
||
|
if pyver < 2.6:
|
||
|
|
||
|
def __cmp__(self, other):
|
||
|
if type(other) is self.__class__:
|
||
|
if self is other:
|
||
|
return 0
|
||
|
return -1
|
||
|
return NotImplemented
|
||
|
raise TypeError("unorderable types: %s() and %s()" % (self.__class__.__name__, other.__class__.__name__))
|
||
|
temp_enum_dict['__cmp__'] = __cmp__
|
||
|
del __cmp__
|
||
|
|
||
|
else:
|
||
|
|
||
|
def __le__(self, other):
|
||
|
raise TypeError("unorderable types: %s() <= %s()" % (self.__class__.__name__, other.__class__.__name__))
|
||
|
temp_enum_dict['__le__'] = __le__
|
||
|
del __le__
|
||
|
|
||
|
def __lt__(self, other):
|
||
|
raise TypeError("unorderable types: %s() < %s()" % (self.__class__.__name__, other.__class__.__name__))
|
||
|
temp_enum_dict['__lt__'] = __lt__
|
||
|
del __lt__
|
||
|
|
||
|
def __ge__(self, other):
|
||
|
raise TypeError("unorderable types: %s() >= %s()" % (self.__class__.__name__, other.__class__.__name__))
|
||
|
temp_enum_dict['__ge__'] = __ge__
|
||
|
del __ge__
|
||
|
|
||
|
def __gt__(self, other):
|
||
|
raise TypeError("unorderable types: %s() > %s()" % (self.__class__.__name__, other.__class__.__name__))
|
||
|
temp_enum_dict['__gt__'] = __gt__
|
||
|
del __gt__
|
||
|
|
||
|
|
||
|
def __eq__(self, other):
|
||
|
if type(other) is self.__class__:
|
||
|
return self is other
|
||
|
return NotImplemented
|
||
|
temp_enum_dict['__eq__'] = __eq__
|
||
|
del __eq__
|
||
|
|
||
|
def __ne__(self, other):
|
||
|
if type(other) is self.__class__:
|
||
|
return self is not other
|
||
|
return NotImplemented
|
||
|
temp_enum_dict['__ne__'] = __ne__
|
||
|
del __ne__
|
||
|
|
||
|
def __hash__(self):
|
||
|
return hash(self._name_)
|
||
|
temp_enum_dict['__hash__'] = __hash__
|
||
|
del __hash__
|
||
|
|
||
|
def __reduce_ex__(self, proto):
|
||
|
return self.__class__, (self._value_, )
|
||
|
temp_enum_dict['__reduce_ex__'] = __reduce_ex__
|
||
|
del __reduce_ex__
|
||
|
|
||
|
# _RouteClassAttributeToGetattr 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.
|
||
|
|
||
|
@_RouteClassAttributeToGetattr
|
||
|
def name(self):
|
||
|
return self._name_
|
||
|
temp_enum_dict['name'] = name
|
||
|
del name
|
||
|
|
||
|
@_RouteClassAttributeToGetattr
|
||
|
def value(self):
|
||
|
return self._value_
|
||
|
temp_enum_dict['value'] = value
|
||
|
del 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
|
||
|
members = dict((name, value) for name, value in source.items() if filter(name))
|
||
|
cls = cls(name, members, module=module)
|
||
|
cls.__reduce_ex__ = _reduce_ex_by_name
|
||
|
module_globals.update(cls.__members__)
|
||
|
module_globals[name] = cls
|
||
|
return cls
|
||
|
temp_enum_dict['_convert'] = _convert
|
||
|
del _convert
|
||
|
|
||
|
Enum = EnumMeta('Enum', (object, ), temp_enum_dict)
|
||
|
del temp_enum_dict
|
||
|
|
||
|
# Enum has now been created
|
||
|
###########################
|
||
|
|
||
|
class IntEnum(int, Enum):
|
||
|
"""Enum where members are also (and must be) ints"""
|
||
|
|
||
|
def _reduce_ex_by_name(self, proto):
|
||
|
return self.name
|
||
|
|
||
|
def unique(enumeration):
|
||
|
"""Class decorator that ensures only unique members exist in an enumeration."""
|
||
|
duplicates = []
|
||
|
for name, member in enumeration.__members__.items():
|
||
|
if name != member.name:
|
||
|
duplicates.append((name, member.name))
|
||
|
if duplicates:
|
||
|
duplicate_names = ', '.join(
|
||
|
["%s -> %s" % (alias, name) for (alias, name) in duplicates]
|
||
|
)
|
||
|
raise ValueError('duplicate names found in %r: %s' %
|
||
|
(enumeration, duplicate_names)
|
||
|
)
|
||
|
return enumeration
|