collect_by_mro is missing in the typed signature

[raabf]

Although the parameter collect_by_mro is implemented in

attrs/src/attr/_make.py

Lines 994 to 1017 in 48157a5

	def attrs(
	maybe_cls=None,
	these=None,
	repr_ns=None,
	repr=None,
	cmp=None,
	hash=None,
	init=None,
	slots=False,
	frozen=False,
	weakref_slot=True,
	str=False,
	auto_attribs=False,
	kw_only=False,
	cache_hash=False,
	auto_exc=False,
	eq=None,
	order=None,
	auto_detect=False,
	collect_by_mro=False,
	getstate_setstate=None,
	on_setattr=None,
	field_transformer=None,
	):

it is missing it the typed signature of the pyi file

attrs/src/attr/__init__.pyi

Lines 257 to 303 in 48157a5

	def attrs(
	maybe_cls: _C,
	these: Optional[Dict[str, Any]] = ...,
	repr_ns: Optional[str] = ...,
	repr: bool = ...,
	cmp: Optional[bool] = ...,
	hash: Optional[bool] = ...,
	init: bool = ...,
	slots: bool = ...,
	frozen: bool = ...,
	weakref_slot: bool = ...,
	str: bool = ...,
	auto_attribs: bool = ...,
	kw_only: bool = ...,
	cache_hash: bool = ...,
	auto_exc: bool = ...,
	eq: Optional[bool] = ...,
	order: Optional[bool] = ...,
	auto_detect: bool = ...,
	getstate_setstate: Optional[bool] = ...,
	on_setattr: Optional[_OnSetAttrArgType] = ...,
	field_transformer: Optional[_FieldTransformer] = ...,
	) -> _C: ...
	@overload
	def attrs(
	maybe_cls: None = ...,
	these: Optional[Dict[str, Any]] = ...,
	repr_ns: Optional[str] = ...,
	repr: bool = ...,
	cmp: Optional[bool] = ...,
	hash: Optional[bool] = ...,
	init: bool = ...,
	slots: bool = ...,
	frozen: bool = ...,
	weakref_slot: bool = ...,
	str: bool = ...,
	auto_attribs: bool = ...,
	kw_only: bool = ...,
	cache_hash: bool = ...,
	auto_exc: bool = ...,
	eq: Optional[bool] = ...,
	order: Optional[bool] = ...,
	auto_detect: bool = ...,
	getstate_setstate: Optional[bool] = ...,
	on_setattr: Optional[_OnSetAttrArgType] = ...,
	field_transformer: Optional[_FieldTransformer] = ...,
	) -> Callable[[_C], _C]: ...

As a consequence, type checkers such as mypy would never allow to use collect_by_mro, since the signature cannot match, although in runtime it would work because the actual implementation of the function has the parameter.

[hynek]

Thanks, should be fixed.

[raabf]

Thank you @hynek 😄, but didn’t you miss the type annotation?
i.e. collect_by_mro: bool = ..., instead of collect_by_mro = ...,?

[hynek]

Waaat. Why does the test pass then. 🤔 Probably implicit Any?

[hynek]

Should be fixed now. Thanks for double-checking!

[raabf]

Thanks! Regarding the test which passes:
I did not find any mypy configuration for the attrs repository. The think the default configuration of mypy allows untyped elements, and just checks those which are typed. To detect such errors like missing types, you should make mypy more restrictive such as with disallow_untyped_defs = True and check_untyped_defs = True, which I think is good when you want to be serious regarding full compatibility with mypy.

[hynek]

You're right, that's how I run my own projects too. attrs's typing setup is a bit more special but this we should add. See 6b4a1f1