def test_isinstance_invalidation(self):
class A(metaclass=abc.ABCMeta):
pass
class B:
pass
b = B()
self.assertFalse(isinstance(b, A))
self.assertFalse(isinstance(b, (A,)))
token_old = abc.get_cache_token()
A.register(B)
token_new = abc.get_cache_token()
self.assertNotEqual(token_old, token_new)
self.assertTrue(isinstance(b, A))
self.assertTrue(isinstance(b, (A,)))
def dispatch(cls, role=None):
"""
Return the implementation for the given type and role.
If role is given, return a function that receives a single positional
argument and any number of keyword arguments. If role is not given,
the return function should receive both an object and a role as
positional arguments.
"""
# Invalidate cache when ABC cache is invalidated
nonlocal cache_token
if cache_token is not None and cache_token != get_cache_token():
dispatch_cache.clear()
cache_token = get_cache_token()
try:
return dispatch_cache[cls, role]
except KeyError:
pass
# Find implementation, if not in cache
if role is None:
impl = no_roles.dispatch(cls)
elif role in roles:
impl = roles[role].dispatch(cls)
else:
impl = partial(no_roles.dispatch(cls), role=role)
# Cache and return
dispatch_cache[cls, role] = impl
return impl
def build_proxy_registry(cls):
if cls.proxy_registry and abc.get_cache_token(
) == cls.last_cache_token:
return
cls.last_cache_token = abc.get_cache_token()
registry = copy(cls.base_proxy_registry)
MatrixProxy._register_subclasses(cls.__subclasses__(), registry)
cls.proxy_registry = registry
def test_isinstance_invalidation(self):
class A(metaclass=abc.ABCMeta):
pass
class B:
pass
b = B()
self.assertFalse(isinstance(b, A))
self.assertFalse(isinstance(b, (A,)))
token_old = abc.get_cache_token()
A.register(B)
token_new = abc.get_cache_token()
self.assertNotEqual(token_old, token_new)
self.assertTrue(isinstance(b, A))
self.assertTrue(isinstance(b, (A,)))
def register(cls, func=None):
"""generic_func.register(cls, func) -> func
Registers a new implementation for the given *cls* on a *generic_func*.
"""
nonlocal cache_token
if func is None:
if isinstance(cls, type):
return lambda f: register(cls, f)
ann = getattr(cls, '__annotations__', {})
if not ann:
raise TypeError(
f"Invalid first argument to `register()`: {cls!r}. "
f"Use either `@register(some_class)` or plain `@register` "
f"on an annotated function.")
func = cls
# only import typing if annotation parsing is necessary
from typing import get_type_hints
argname, cls = next(iter(get_type_hints(func).items()))
assert isinstance(cls, type), (
f"Invalid annotation for {argname!r}. {cls!r} is not a group.")
registry[cls] = func
if cache_token is None and hasattr(cls, '__abstractmethods__'):
cache_token = get_cache_token()
dispatch_cache.clear()
return func
def dispatch(cls):
"""generic_func.dispatch(cls) -> <function implementation>
Runs the dispatch algorithm to return the best available implementation
for the given *cls* registered on *generic_func*.
"""
nonlocal cache_token
if cache_token is not None:
current_token = get_cache_token()
if cache_token != current_token:
dispatch_cache.clear()
cache_token = current_token
try:
impl = dispatch_cache[cls]
except KeyError:
try:
impl = registry[cls]
except KeyError:
impl = find_implementation(cls, registry)
if impl is func and lazy_registry:
for qualname in possible_qualnames(cls):
if qualname in lazy_registry:
impl = lazy_registry.pop(qualname)
register(cls)(impl)
break
dispatch_cache[cls] = impl
return impl
def _dispatch(cls, vcls):
global _cache_token
if _cache_token is not None:
current_token = get_cache_token()
if _cache_token != current_token:
_dispatch_cache.clear()
_cache_token = current_token
try:
func = _dispatch_cache[(cls, vcls)]
except KeyError:
try:
vreg = _registry[cls]
except KeyError:
vreg = _find_impl(cls, _registry)
if not vreg:
raise NotImplementedError(
f"No implementation found for '{cls.__qualname__}'")
try:
return vreg[vcls]
except KeyError:
func = _find_impl(vcls, vreg)
if not func:
raise TypeError(
f"No implementation found for '{cls.__qualname__}' from {vcls.__qualname__}")
_dispatch_cache[(cls, vcls)] = func
return func
def register(cls, impl=None):
"""generic_func.register(cls, impl) -> impl
Registers a new implementation for the given *cls* on a *generic_func*.
"""
nonlocal cache_token
# First argument is a list of classes: iterate over all classes
# registering one at a time.
if not isinstance(cls, (type, str)):
cls_list = list(cls)
if impl is not None:
for cls in cls_list:
register(cls, impl)
return
# Single class
if impl is None:
return lambda f: register(cls, f)
if isinstance(cls, str):
lazy_registry[cls] = impl
else:
registry[cls] = impl
if cache_token is None and hasattr(cls, "__abstractmethods__"):
cache_token = get_cache_token()
dispatch_cache.clear()
return impl
def register(cls, func=None):
"""generic_func.register(cls, func) -> func
Registers a new implementation for the given *cls* on a *generic_func*.
"""
nonlocal cache_token
if func is None:
if isinstance(cls, type):
return lambda f: register(cls, f)
ann = getattr(cls, '__annotations__', {})
if not ann:
raise TypeError(
f"Invalid first argument to `register()`: {cls!r}. "
f"Use either `@register(some_class)` or plain `@register` "
f"on an annotated function."
)
func = cls
# only import typing if annotation parsing is necessary
from typing import get_type_hints
argname, cls = next(iter(get_type_hints(func).items()))
assert isinstance(cls, type), (
f"Invalid annotation for {argname!r}. {cls!r} is not a class."
)
registry[cls] = func
if cache_token is None and hasattr(cls, '__abstractmethods__'):
cache_token = get_cache_token()
dispatch_cache.clear()
return func
def __init__(self, default_callback: Callable[..., T]):
self.default_callback = default_callback
self.__name__ = default_callback.__name__
self.candidate_sets: Dict[int, Set[Candidate]] = defaultdict(set)
self._cache_token = get_cache_token()
self._layers_cache: Dict[int, List[Set[Candidate]]] = {}
self._lookup_cache: Dict[
int, WeakTupleDict[List[LookupLayer]]] = defaultdict(WeakTupleDict)
def decorator(implementation):
container = self._protocols if is_protocol else self._instances
container[type_argument] = implementation # type: ignore
if self._cache_token is None: # pragma: no cover
if getattr(type_argument, '__abstractmethods__', None):
self._cache_token = get_cache_token()
self._dispatch_cache.clear()
return implementation
def test_isinstance_invalidation(abc): # pylint: disable=unused-argument
"""Test after-the-fact registration behavior.
Adapted from Python's test suite.
"""
class AClass(metaclass=abc.NamespaceableABCMeta):
"""A throwaway test class."""
class BClass:
"""A throwaway test class."""
b_instance = BClass()
assert not isinstance(b_instance, AClass)
assert not isinstance(b_instance, (AClass, ))
token_old = abc_main.get_cache_token()
AClass.register(BClass)
token_new = abc_main.get_cache_token()
assert token_old != token_new
assert isinstance(b_instance, AClass)
assert isinstance(b_instance, (AClass, ))
def _control_abc_cache(self) -> None:
"""
Required to drop cache if ``abc`` type got new subtypes in runtime.
Copied from ``cpython``.
"""
if self._cache_token is not None:
current_token = get_cache_token()
if self._cache_token != current_token:
self._dispatch_cache.clear()
self._cache_token = current_token
def register(cls, func=None):
"""generic_func.register(cls, func) -> func
Registers a new implementation for the given *cls* on a *generic_func*.
"""
nonlocal cache_token
if func is None:
return lambda f: register(cls, f)
registry[cls] = func
if cache_token is None and hasattr(cls, '__abstractmethods__'):
cache_token = get_cache_token()
dispatch_cache.clear()
return func
def register(cls, func=None):
"""generic_func.register(cls, func) -> func
Registers a new implementation for the given *cls* on a *generic_func*.
"""
nonlocal cache_token
if func is None:
return lambda f: register(cls, f)
registry[cls] = func
if cache_token is None and hasattr(cls, '__abstractmethods__'):
cache_token = get_cache_token()
dispatch_cache.clear()
return func
def __call__(self, *args, **kwargs):
new_cache_token = get_cache_token()
if new_cache_token != self._cache_token:
# our cache is out of date and must be rebuilt
self.clear_cache()
self._cache_token = new_cache_token
t_args = tuple(type(a) for a in args)
ll = self._get_lookup_layers(t_args)
for layer in ll:
if isinstance(layer, Exception):
raise layer
ret = layer.callback(*args, **kwargs)
if ret is not NotImplemented:
return ret
return self.default_callback(*args, **kwargs)
def _register(func):
global _cache_token
sig = signature(func)
if len(sig.parameters) < 3:
raise TypeError(
f"{func!r}() takes {len(sig.parameters)} arguments but 3 required")
it = iter(sig.parameters.items())
argname, parameter = next(it)
hints = get_type_hints(func)
typ = hints.get(argname)
if typ:
type_args = _get_type_args(typ)
if get_origin(typ) is not type or not type_args:
raise TypeError(
f"Invalid first argument to `cast.register()`: {typ!r}. "
f"Use either typing.Type[] annotation or return type annotation."
)
cls = type_args[0]
else:
cls = hints.get('return')
if cls is None:
raise TypeError(
f"Invalid signature to `cast.register()`. "
f"Use either typing.Type[] annotation or return type annotation."
)
argname, parameter = next(it)
vcls = hints.get(argname)
if not vcls:
vcls = Any
if vcls == Any:
vcls = object
if cls in _registry:
if vcls in _registry[cls]:
raise RuntimeError(f"Ambiguous `cast.register()`")
_registry[cls][vcls] = func
else:
_registry[cls] = {vcls: func}
setattr(func, _TYPES, (cls, vcls))
if _cache_token is None:
if hasattr(cls, '__abstractmethods__') or hasattr(vcls, '__abstractmethods__'):
_cache_token = get_cache_token()
_dispatch_cache.clear()
return func
def register(cls, func=None):
"""generic_func.register(cls, func) -> func
Registers a new implementation for the given *cls* on a *generic_func*.
"""
nonlocal cache_token
if _is_valid_dispatch_type(cls):
if func is None:
return lambda f: register(cls, f)
else:
if func is not None:
raise TypeError(f"Invalid first argument to `register()`. "
f"{cls!r} is not a class or union type.")
ann = getattr(cls, '__annotations__', {})
if not ann:
raise TypeError(
f"Invalid first argument to `register()`: {cls!r}. "
f"Use either `@register(some_class)` or plain `@register` "
f"on an annotated function.")
func = cls
# only import typing if annotation parsing is necessary
from typing import get_type_hints
argname, cls = next(iter(get_type_hints(func).items()))
if not _is_valid_dispatch_type(cls):
if _is_union_type(cls):
raise TypeError(f"Invalid annotation for {argname!r}. "
f"{cls!r} not all arguments are classes.")
else:
raise TypeError(f"Invalid annotation for {argname!r}. "
f"{cls!r} is not a class.")
if _is_union_type(cls):
from typing import get_args
for arg in get_args(cls):
registry[arg] = func
else:
registry[cls] = func
if cache_token is None and hasattr(cls, '__abstractmethods__'):
cache_token = get_cache_token()
dispatch_cache.clear()
return func
def register(cls=None, func=None):
"""generic_func.register(cls, func) -> func
Registers a new implementation for the given *cls* on a *generic_func*.
"""
nonlocal cache_token
if func is None:
return lambda f: register(cls, f)
if cls is None:
sign = inspect.signature(func)
params = sign.parameters
cls = list(params.values())[disp_param].annotation
registry[cls] = func
if cache_token is None and hasattr(cls, '__abstractmethods__'):
cache_token = get_cache_token()
dispatch_cache.clear()
return func
def dispatch(cls):
"""generic_func.dispatch(cls) -> <function implementation>
Runs the dispatch algorithm to return the best available implementation
for the given *cls* registered on *generic_func*.
"""
nonlocal cache_token
if cache_token is not None:
current_token = get_cache_token()
if cache_token != current_token:
dispatch_cache.clear()
cache_token = current_token
try:
impl = dispatch_cache[cls]
except KeyError:
try:
impl = registry[cls]
except KeyError:
impl = _find_impl(cls, registry)
dispatch_cache[cls] = impl
return impl
def dispatch(cls):
"""generic_func.dispatch(cls) -> <function implementation>
Runs the dispatch algorithm to return the best available implementation
for the given *cls* registered on *generic_func*.
"""
nonlocal cache_token
if cache_token is not None:
current_token = get_cache_token()
if cache_token != current_token:
dispatch_cache.clear()
cache_token = current_token
try:
impl = dispatch_cache[cls]
except KeyError:
try:
impl = registry[cls]
except KeyError:
impl = _find_impl(cls, registry)
dispatch_cache[cls] = impl
return impl
def get_token(self):
return abc.get_cache_token()
from typing import get_type_hints
argname, cls = next(iter(get_type_hints(func).items()))
<<<<<<< HEAD
assert isinstance(cls, type), (
f"Invalid annotation for {argname!r}. {cls!r} is not a class."
)
=======
if not isinstance(cls, type):
raise TypeError(
f"Invalid annotation for {argname!r}. "
f"{cls!r} is not a class."
)
>>>>>>> 716b15a33aed978ded8a6bde17855cb6c6aa7f78
registry[cls] = func
if cache_token is None and hasattr(cls, '__abstractmethods__'):
cache_token = get_cache_token()
dispatch_cache.clear()
return func
def wrapper(*args, **kw):
if not args:
raise TypeError(f'{funcname} requires at least '
'1 positional argument')
return dispatch(args[0].__class__)(*args, **kw)
funcname = getattr(func, '__name__', 'singledispatch function')
registry[object] = func
wrapper.register = register
wrapper.dispatch = dispatch
wrapper.registry = types.MappingProxyType(registry)
def update_event(self, inp=-1):
self.set_output_val(0, abc.get_cache_token())
