python / python/mypy

`explicit-override` false positive when overriding property with setter

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bug
Dominant language
Python
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Description

# mypy: enable-error-code=explicit-override

from typing_extensions import override


class Foo:
    @property
    def foo(self) -> int:
        return 1

    @foo.setter
    def foo(self, value: int) -> None:
        ...


class Bar(Foo):
    @property  # error: explicit-override
    @override
    def foo(self) -> int:
        return 2

    @foo.setter
    def foo(self, value: int) -> None:
        ...

playground

putting @override on the setter does not fix it (and it shouldn't be required anyway, as that would be inconsistent with other decorators such as @abstractmethod)

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by running the issue's minimal example in the linked mypy playground and confirm the false positive on the property decorator. Trace the explicit-override handling for a property overridden with a getter and setter. Done means the getter can carry @override without an error, and decorating the setter is not required.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
devtools
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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