Documentation
Consider this code snippet:
from typing import Iterable
class A:
attr1: Iterable[str] # narrows to different type, specific number of elements.
attr2: tuple[str, ...] # narrows to specific number of elements
class B(A):
attr1 = "a", "b"
attr2 = "a", "b", "c"
reveal_type(B.attr1)
reveal_type(B.attr2)With this, mypy will tell us that Revealed type is "Tuple[builtins.str, builtins.str]" and Revealed type is "Tuple[builtins.str, builtins.str, builtins.str]" for attr1 and attr2 respectively. I can't find this behaviour documented, neither in PEP484, nor the Python typing docs, nor mypy docs. I don't even know where this should be documented best. But for what it's worth, I asked pylance, which says Type of "B.attr1" is "tuple[str, ...]" and Type of "B.attr2" is "tuple[str, ...]". Which tells me that the intended behaviour isn't clear for other people, too.
Note: I'm aware that this may be a bug report instead. But I rather err on the side of this not being clearly specified yet than being incorrectly implemented.
Documentation
Consider this code snippet:
With this,
mypywill tell us thatRevealed type is "Tuple[builtins.str, builtins.str]"andRevealed type is "Tuple[builtins.str, builtins.str, builtins.str]"forattr1andattr2respectively. I can't find this behaviour documented, neither in PEP484, nor the Python typing docs, nor mypy docs. I don't even know where this should be documented best. But for what it's worth, I asked pylance, which saysType of "B.attr1" is "tuple[str, ...]"andType of "B.attr2" is "tuple[str, ...]". Which tells me that the intended behaviour isn't clear for other people, too.Note: I'm aware that this may be a bug report instead. But I rather err on the side of this not being clearly specified yet than being incorrectly implemented.