cpython/Lib/types.py at 3.13 · python/cpython · GitHub

Name: cpython/Lib/types.py at 3.13 · python/cpython · GitHub
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"""
Define names for built-in types that aren't directly accessible as a builtin.
"""

importsys

# Iterators in Python aren't a matter of type but of protocol. A large
# and changing number of builtin types implement *some* flavor of
# iterator. Don't check the type! Use hasattr to check for both
# "__iter__" and "__next__" attributes instead.

def_f(): pass
FunctionType=type(_f)
LambdaType=type(lambda: None) # Same as FunctionType
CodeType=type(_f.__code__)
MappingProxyType=type(type.__dict__)
SimpleNamespace=type(sys.implementation)

def_cell_factory():
a=1
deff():
nonlocala
returnf.__closure__[0]
CellType=type(_cell_factory())

def_g():
yield1
GeneratorType=type(_g())

asyncdef_c(): pass
_c=_c()
CoroutineType=type(_c)
_c.close() # Prevent ResourceWarning

asyncdef_ag():
yield
_ag=_ag()
AsyncGeneratorType=type(_ag)

class_C:
def_m(self): pass
MethodType=type(_C()._m)

BuiltinFunctionType=type(len)
BuiltinMethodType=type([].append) # Same as BuiltinFunctionType

WrapperDescriptorType=type(object.__init__)
MethodWrapperType=type(object().__str__)
MethodDescriptorType=type(str.join)
ClassMethodDescriptorType=type(dict.__dict__['fromkeys'])

ModuleType=type(sys)

try:
raiseTypeError
exceptTypeErrorasexc:
TracebackType=type(exc.__traceback__)
FrameType=type(exc.__traceback__.tb_frame)

GetSetDescriptorType=type(FunctionType.__code__)
MemberDescriptorType=type(FunctionType.__globals__)

delsys, _f, _g, _C, _c, _ag, _cell_factory# Not for export


# Provide a PEP 3115 compliant mechanism for class creation
defnew_class(name, bases=(), kwds=None, exec_body=None):
"""Create a class object dynamically using the appropriate metaclass."""
resolved_bases=resolve_bases(bases)
meta, ns, kwds=prepare_class(name, resolved_bases, kwds)
ifexec_bodyisnotNone:
exec_body(ns)
ifresolved_basesisnotbases:
ns['__orig_bases__'] =bases
returnmeta(name, resolved_bases, ns, **kwds)

defresolve_bases(bases):
"""Resolve MRO entries dynamically as specified by PEP 560."""
new_bases=list(bases)
updated=False
shift=0
fori, baseinenumerate(bases):
ifisinstance(base, type):
continue
ifnothasattr(base, "__mro_entries__"):
continue
new_base=base.__mro_entries__(bases)
updated=True
ifnotisinstance(new_base, tuple):
raiseTypeError("__mro_entries__ must return a tuple")
else:
new_bases[i+shift:i+shift+1] =new_base
shift+=len(new_base) -1
ifnotupdated:
returnbases
returntuple(new_bases)

defprepare_class(name, bases=(), kwds=None):
"""Call the __prepare__ method of the appropriate metaclass.

 Returns (metaclass, namespace, kwds) as a 3-tuple

 *metaclass* is the appropriate metaclass
 *namespace* is the prepared class namespace
 *kwds* is an updated copy of the passed in kwds argument with any
 'metaclass' entry removed. If no kwds argument is passed in, this will
 be an empty dict.
 """
ifkwdsisNone:
kwds= {}
else:
kwds=dict(kwds) # Don't alter the provided mapping
if'metaclass'inkwds:
meta=kwds.pop('metaclass')
else:
ifbases:
meta=type(bases[0])
else:
meta=type
ifisinstance(meta, type):
# when meta is a type, we first determine the most-derived metaclass
# instead of invoking the initial candidate directly
meta=_calculate_meta(meta, bases)
ifhasattr(meta, '__prepare__'):
ns=meta.__prepare__(name, bases, **kwds)
else:
ns= {}
returnmeta, ns, kwds

def_calculate_meta(meta, bases):
"""Calculate the most derived metaclass."""
winner=meta
forbaseinbases:
base_meta=type(base)
ifissubclass(winner, base_meta):
continue
ifissubclass(base_meta, winner):
winner=base_meta
continue
# else:
raiseTypeError("metaclass conflict: "
"the metaclass of a derived class "
"must be a (non-strict) subclass "
"of the metaclasses of all its bases")
returnwinner


defget_original_bases(cls, /):
"""Return the class's "original" bases prior to modification by `__mro_entries__`.

 Examples::

 from typing import TypeVar, Generic, NamedTuple, TypedDict

 T = TypeVar("T")
 class Foo(Generic[T]): ...
 class Bar(Foo[int], float): ...
 class Baz(list[str]): ...
 Eggs = NamedTuple("Eggs", [("a", int), ("b", str)])
 Spam = TypedDict("Spam", {"a": int, "b": str})

 assert get_original_bases(Bar) == (Foo[int], float)
 assert get_original_bases(Baz) == (list[str],)
 assert get_original_bases(Eggs) == (NamedTuple,)
 assert get_original_bases(Spam) == (TypedDict,)
 assert get_original_bases(int) == (object,)
 """
try:
returncls.__dict__.get("__orig_bases__", cls.__bases__)
exceptAttributeError:
raiseTypeError(
f"Expected an instance of type, not {type(cls).__name__!r}"
 ) fromNone


classDynamicClassAttribute:
"""Route attribute access on a class to __getattr__.

 This is a descriptor, used to define attributes that act differently when
 accessed through an instance and through a class. Instance access remains
 normal, but access to an attribute through a class will be routed to the
 class's __getattr__ method; this is done by raising AttributeError.

 This allows one to have properties active on an instance, and have virtual
 attributes on the class with the same name. (Enum used this between Python
 versions 3.4 - 3.9 .)

 Subclass from this to use a different method of accessing virtual attributes
 and still be treated properly by the inspect module. (Enum uses this since
 Python 3.10 .)

 """
def__init__(self, fget=None, fset=None, fdel=None, doc=None):
self.fget=fget
self.fset=fset
self.fdel=fdel
# next two lines make DynamicClassAttribute act the same as property
self.__doc__=docorfget.__doc__
self.overwrite_doc=docisNone
# support for abstract methods
self.__isabstractmethod__=bool(getattr(fget, '__isabstractmethod__', False))

def__get__(self, instance, ownerclass=None):
ifinstanceisNone:
ifself.__isabstractmethod__:
returnself
raiseAttributeError()
elifself.fgetisNone:
raiseAttributeError("unreadable attribute")
returnself.fget(instance)

def__set__(self, instance, value):
ifself.fsetisNone:
raiseAttributeError("can't set attribute")
self.fset(instance, value)

def__delete__(self, instance):
ifself.fdelisNone:
raiseAttributeError("can't delete attribute")
self.fdel(instance)

defgetter(self, fget):
fdoc=fget.__doc__ifself.overwrite_docelseNone
result=type(self)(fget, self.fset, self.fdel, fdocorself.__doc__)
result.overwrite_doc=self.overwrite_doc
returnresult

defsetter(self, fset):
result=type(self)(self.fget, fset, self.fdel, self.__doc__)
result.overwrite_doc=self.overwrite_doc
returnresult

defdeleter(self, fdel):
result=type(self)(self.fget, self.fset, fdel, self.__doc__)
result.overwrite_doc=self.overwrite_doc
returnresult


class_GeneratorWrapper:
# TODO: Implement this in C.
def__init__(self, gen):
self.__wrapped=gen
self.__isgen=gen.__class__isGeneratorType
self.__name__=getattr(gen, '__name__', None)
self.__qualname__=getattr(gen, '__qualname__', None)
defsend(self, val):
returnself.__wrapped.send(val)
defthrow(self, tp, *rest):
returnself.__wrapped.throw(tp, *rest)
defclose(self):
returnself.__wrapped.close()
@property
defgi_code(self):
returnself.__wrapped.gi_code
@property
defgi_frame(self):
returnself.__wrapped.gi_frame
@property
defgi_running(self):
returnself.__wrapped.gi_running
@property
defgi_yieldfrom(self):
returnself.__wrapped.gi_yieldfrom
cr_code=gi_code
cr_frame=gi_frame
cr_running=gi_running
cr_await=gi_yieldfrom
def__next__(self):
returnnext(self.__wrapped)
def__iter__(self):
ifself.__isgen:
returnself.__wrapped
returnself
__await__=__iter__

defcoroutine(func):
"""Convert regular generator function to a coroutine."""

ifnotcallable(func):
raiseTypeError('types.coroutine() expects a callable')

if (func.__class__isFunctionTypeand
getattr(func, '__code__', None).__class__isCodeType):

co_flags=func.__code__.co_flags

# Check if 'func' is a coroutine function.
# (0x180 == CO_COROUTINE | CO_ITERABLE_COROUTINE)
ifco_flags&0x180:
returnfunc

# Check if 'func' is a generator function.
# (0x20 == CO_GENERATOR)
ifco_flags&0x20:
# TODO: Implement this in C.
co=func.__code__
# 0x100 == CO_ITERABLE_COROUTINE
func.__code__=co.replace(co_flags=co.co_flags|0x100)
returnfunc

# The following code is primarily to support functions that
# return generator-like objects (for instance generators
# compiled with Cython).

# Delay functools and _collections_abc import for speeding up types import.
importfunctools
import_collections_abc
@functools.wraps(func)
defwrapped(*args, **kwargs):
coro=func(*args, **kwargs)
if (coro.__class__isCoroutineTypeor
coro.__class__isGeneratorTypeandcoro.gi_code.co_flags&0x100):
# 'coro' is a native coroutine object or an iterable coroutine
returncoro
if (isinstance(coro, _collections_abc.Generator) and
notisinstance(coro, _collections_abc.Coroutine)):
# 'coro' is either a pure Python generator iterator, or it
# implements collections.abc.Generator (and does not implement
# collections.abc.Coroutine).
return_GeneratorWrapper(coro)
# 'coro' is either an instance of collections.abc.Coroutine or
# some other object -- pass it through.
returncoro

returnwrapped

GenericAlias=type(list[int])
UnionType=type(int|str)

EllipsisType=type(Ellipsis)
NoneType=type(None)
NotImplementedType=type(NotImplemented)

def__getattr__(name):
ifname=='CapsuleType':
import_socket
returntype(_socket.CAPI)
raiseAttributeError(f"module {__name__!r} has no attribute {name!r}")

__all__= [nforninglobals() ifn[:1] !='_']
__all__+= ['CapsuleType']