[PEP 695] Allow covariance with attribute that has "_" name prefix #17782
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Fix this conformance test:
```
class ShouldBeCovariant5[T]:
def __init__(self, x: T) -> None:
self._x = x
@Property
def x(self) -> T:
return self._x
vo5_1: ShouldBeCovariant5[float] = ShouldBeCovariant5[int](1) # OK
vo5_2: ShouldBeCovariant5[int] = ShouldBeCovariant5[float](1) # E
```
My fix is to treat such attributes a not settable when inferring variance.
Link:
https://github.com/python/typing/blob/main/conformance/tests/generics_variance_inference.py#L79
|
According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅ |
svalentin
approved these changes
Sep 18, 2024
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Fix this conformance test:
My fix is to treat such attributes as not settable when inferring variance.
Link:
https://github.com/python/typing/blob/main/conformance/tests/generics_variance_inference.py#L79