Description
openedon Jan 14, 2022
Describe the bug
pyright will crash if Self is used as a generic argument to a decorator inside a class
To Reproduce
See code below, pyright emits the following error.
An internal error occurred while type checking file "test2.py": RangeError: Maximum call stack size exceeded
at useSpeculativeMode ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:17159:36)
at validateFunctionArgumentTypes ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:9160:17)
at validateFunctionArguments ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:9352:16)
at callback ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:7804:48)
at callback ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:3129:39)
at doForEachSubtype ([...]\pyright\dist\pyright-internal\src\analyzer\typeUtils.ts:405:9)
at expandSubtype ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:3122:13)
at mapSubtypesExpandTypeVars ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:3153:13)
at validateCallArguments ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:7757:28)
at Ct ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:6505:36)
Error performing analysis: RangeError: Maximum call stack size exceeded
at useSpeculativeMode ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:17159:36)
at validateFunctionArgumentTypes ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:9160:17)
at validateFunctionArguments ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:9352:16)
at callback ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:7804:48)
at callback ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:3129:39)
at doForEachSubtype ([...]\pyright\dist\pyright-internal\src\analyzer\typeUtils.ts:405:9)
at expandSubtype ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:3122:13)
at mapSubtypesExpandTypeVars ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:3153:13)
at validateCallArguments ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:7757:28)
at Ct ([...]\pyright\dist\pyright-internal\src\analyzer\typeEvaluator.ts:6505:36)Expected behavior
Not actually sure what's expected here, I'd like if Self was allowed in the context, but I'm not sure if it's supposed to be.
Screenshots or Code
If applicable, add screenshots or the text of the code (surrounded by triple back ticks) to help explain your problem.
from typing import Any, Callable, Generic, Type, TYPE_CHECKING, TypeVar
if TYPE_CHECKING:
from typing_extensions import Self
else:
Self = TypeVar('Self')
T = TypeVar('T')
def my_deco(cls: Type[T]) -> Callable[..., T]:
return lambda f: cls()
class Foo(Generic[T]):
...
class Bar:
@my_deco(Foo[Self])
def foo() -> None:
...
reveal_type(Bar.foo)VS Code extension or command-line
Pre 1.1.209
Additional context
Using @Gobot1234's mypy fork with Self support this type-checks fine reveal_type outputs test2.Foo*[Self@test2.Bar]
Unsure if that's the expected behaviour but if the reference implimentation allows it I suspect pyright should too?
Additional to that,
class Foo:
instances: ClassVar[List[Self]]pyright will dissalow this code as classvars cannot include type-variables, However, the mypy implementation will allow Self explicitly, should pyright follow suit?
