@pytest.mark.asyncio
async def test_gotcha() -> None:
async def foo(r: Dict[str, str] = defaultdict() ) -> Dict[str, str]:
return r
assert await foo() is await foo()
@dependant
> async def bar(r: Dict[str, str] = Depends(defaultdict)) -> Dict[str, str]:
tests/test_examples.py:17:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
dependable/decorator.py:15: in __init__
self.dependant: Dependant = get_dependant(call=call)
dependable/utils.py:109: in get_dependant
sub_dependant = get_param_sub_dependant(param=param)
dependable/utils.py:89: in get_param_sub_dependant
return get_dependant(
dependable/utils.py:102: in get_dependant
call_signature = get_typed_signature(call)
dependable/utils.py:65: in get_typed_signature
signature = inspect.signature(call)
/usr/local/lib/python3.9/inspect.py:3130: in signature
return Signature.from_callable(obj, follow_wrapped=follow_wrapped)
/usr/local/lib/python3.9/inspect.py:2879: in from_callable
return _signature_from_callable(obj, sigcls=cls,
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
obj = <class 'collections.defaultdict'>
def _signature_from_callable(obj, *,
follow_wrapper_chains=True,
skip_bound_arg=True,
sigcls):
"""Private helper function to get signature for arbitrary
callable objects.
"""
if not callable(obj):
raise TypeError('{!r} is not a callable object'.format(obj))
if isinstance(obj, types.MethodType):
# In this case we skip the first parameter of the underlying
# function (usually `self` or `cls`).
sig = _signature_from_callable(
obj.__func__,
follow_wrapper_chains=follow_wrapper_chains,
skip_bound_arg=skip_bound_arg,
sigcls=sigcls)
if skip_bound_arg:
return _signature_bound_method(sig)
else:
return sig
# Was this function wrapped by a decorator?
if follow_wrapper_chains:
obj = unwrap(obj, stop=(lambda f: hasattr(f, "__signature__")))
if isinstance(obj, types.MethodType):
# If the unwrapped object is a *method*, we might want to
# skip its first parameter (self).
# See test_signature_wrapped_bound_method for details.
return _signature_from_callable(
obj,
follow_wrapper_chains=follow_wrapper_chains,
skip_bound_arg=skip_bound_arg,
sigcls=sigcls)
try:
sig = obj.__signature__
except AttributeError:
pass
else:
if sig is not None:
if not isinstance(sig, Signature):
raise TypeError(
'unexpected object {!r} in __signature__ '
'attribute'.format(sig))
return sig
try:
partialmethod = obj._partialmethod
except AttributeError:
pass
else:
if isinstance(partialmethod, functools.partialmethod):
# Unbound partialmethod (see functools.partialmethod)
# This means, that we need to calculate the signature
# as if it's a regular partial object, but taking into
# account that the first positional argument
# (usually `self`, or `cls`) will not be passed
# automatically (as for boundmethods)
wrapped_sig = _signature_from_callable(
partialmethod.func,
follow_wrapper_chains=follow_wrapper_chains,
skip_bound_arg=skip_bound_arg,
sigcls=sigcls)
sig = _signature_get_partial(wrapped_sig, partialmethod, (None,))
first_wrapped_param = tuple(wrapped_sig.parameters.values())[0]
if first_wrapped_param.kind is Parameter.VAR_POSITIONAL:
# First argument of the wrapped callable is `*args`, as in
# `partialmethod(lambda *args)`.
return sig
else:
sig_params = tuple(sig.parameters.values())
assert (not sig_params or
first_wrapped_param is not sig_params[0])
new_params = (first_wrapped_param,) + sig_params
return sig.replace(parameters=new_params)
if isfunction(obj) or _signature_is_functionlike(obj):
# If it's a pure Python function, or an object that is duck type
# of a Python function (Cython functions, for instance), then:
return _signature_from_function(sigcls, obj,
skip_bound_arg=skip_bound_arg)
if _signature_is_builtin(obj):
return _signature_from_builtin(sigcls, obj,
skip_bound_arg=skip_bound_arg)
if isinstance(obj, functools.partial):
wrapped_sig = _signature_from_callable(
obj.func,
follow_wrapper_chains=follow_wrapper_chains,
skip_bound_arg=skip_bound_arg,
sigcls=sigcls)
return _signature_get_partial(wrapped_sig, obj)
sig = None
if isinstance(obj, type):
# obj is a class or a metaclass
# First, let's see if it has an overloaded __call__ defined
# in its metaclass
call = _signature_get_user_defined_method(type(obj), '__call__')
if call is not None:
sig = _signature_from_callable(
call,
follow_wrapper_chains=follow_wrapper_chains,
skip_bound_arg=skip_bound_arg,
sigcls=sigcls)
else:
# Now we check if the 'obj' class has a '__new__' method
new = _signature_get_user_defined_method(obj, '__new__')
if new is not None:
sig = _signature_from_callable(
new,
follow_wrapper_chains=follow_wrapper_chains,
skip_bound_arg=skip_bound_arg,
sigcls=sigcls)
else:
# Finally, we should have at least __init__ implemented
init = _signature_get_user_defined_method(obj, '__init__')
if init is not None:
sig = _signature_from_callable(
init,
follow_wrapper_chains=follow_wrapper_chains,
skip_bound_arg=skip_bound_arg,
sigcls=sigcls)
if sig is None:
# At this point we know, that `obj` is a class, with no user-
# defined '__init__', '__new__', or class-level '__call__'
for base in obj.__mro__[:-1]:
# Since '__text_signature__' is implemented as a
# descriptor that extracts text signature from the
# class docstring, if 'obj' is derived from a builtin
# class, its own '__text_signature__' may be 'None'.
# Therefore, we go through the MRO (except the last
# class in there, which is 'object') to find the first
# class with non-empty text signature.
try:
text_sig = base.__text_signature__
except AttributeError:
pass
else:
if text_sig:
# If 'obj' class has a __text_signature__ attribute:
# return a signature based on it
return _signature_fromstr(sigcls, obj, text_sig)
# No '__text_signature__' was found for the 'obj' class.
# Last option is to check if its '__init__' is
# object.__init__ or type.__init__.
if type not in obj.__mro__:
# We have a class (not metaclass), but no user-defined
# __init__ or __new__ for it
if (obj.__init__ is object.__init__ and
obj.__new__ is object.__new__):
# Return a signature of 'object' builtin.
return sigcls.from_callable(object)
else:
> raise ValueError(
'no signature found for builtin type {!r}'.format(obj))
E ValueError: no signature found for builtin type <class 'collections.defaultdict'>
/usr/local/lib/python3.9/inspect.py:2410: ValueError
