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User generic with TypeVarTuple does not check for minimal type of arguments #99382
Description
The following code:
from typing import *
T = TypeVar('T')
T2 = TypeVar('T2')
Ts = TypeVarTuple('Ts')
class A(Generic[T, T2, *Ts]):
x: List[T]
y: List[T2]
z: Tuple[*Ts]
A[int]is executed without errors. It is expected to get an error because A requires at least two arguments.
Without TypeVarTuple you get helpful errors.
class B(Generic[T, T2]):
pass
B[int]
B[int, str, bytes]TypeError: Too few arguments for <class '__main__.B'>; actual 1, expected 2
TypeError: Too many arguments for <class '__main__.B'>; actual 3, expected 2
Activity
sobolevn commentedon Nov 11, 2022
The code says this:
cpython/Lib/typing.py
Lines 1833 to 1836 in f531b68
pythongh-99344, pythongh-99379, pythongh-99382: Fix issues in substit…
gh-99344, gh-99379, gh-99382: Fix issues in substitution of ParamSpec…
pythongh-99344, pythongh-99379, pythongh-99382: Fix issues in substit…
pythongh-99344, pythongh-99379, pythongh-99382: Fix issues in substit…
gh-99344, gh-99379, gh-99382: Fix issues in substitution of ParamSpec…
Check for minimal type args in generics due to python/cpython#99382
AlexWaygood commentedon May 23, 2023
I believe that this has been fixed and backported (in #99412 and #99866). Closing as completed.
(Feel free to reopen if I'm incorrect.)