Repository navigation
Type override for attributes is not checked #2211
Description
from what I see, overriding an attribute with an incompatible type (which can lead to unsoundness) does not produce any kind of warning with mypy:
class Base:
attr = "foo"
def f(self) -> str:
return self.attr
class Derived(Base):
attr = 42
d = Derived()
reveal_type(d.f())The code above shows that mypy thinks that the d.f() expression is a string, while it's actually an int. Shouldn't this kind of redefinitions be forbidden?
Activity
gvanrossum commentedon Oct 3, 2016
dmoisset commentedon Oct 3, 2016
I have looked before opening but couldn't find one... After a second look, there's a mention to this in #1338 , but they seem to be two related but distinct issues.
gvanrossum commentedon Oct 3, 2016
For class variables, lookup type in base classes (#1338, #2022, #2211) (
Revert "For class variables, lookup type in base classes (#1338, #2022,
Revert "For class variables, lookup type in base classes (#1338, #2022,
For class variables, lookup type in base classes (#1338, #2022, #2211) (
gvanrossum commentedon Jan 27, 2017
Fixed by #2510.