B027 and typing.overload

[yakMM]

Consider the following:

class Foo(ABC):
    @t.overload
    def bar(self, arg: t.Literal[False]) -> t.Literal[False]:
        ...

    @t.overload
    def bar(self, arg: t.Literal[True]) -> t.Literal[True]:
        ...

    def bar(self, arg: bool) -> bool:
        return arg

    @abstractmethod
    def abstract_method(self) -> None:
        ...

The overloads of bar are considered as "real" methods and B027 warning is emitted:

 B027 bar is an empty method in an abstract base class, but has no abstract decorator. Consider adding @abstractmethod.
 B027 bar is an empty method in an abstract base class, but has no abstract decorator. Consider adding @abstractmethod.

Is it worth not emitting the warning when typing.overload is used or is it a case that should be supressed manually with # noqa?

[jakkdl]

B027 checks for @overload and @typing.overload https://github.com/PyCQA/flake8-bugbear/blob/main/bugbear.py#L672

but since you did import typing as t it's not picked up by the linter. Searching github it seems that's relatively common, so I can add that to the logic as well.

[yakMM]

Ah okay makes sense, I didn't know this kind of details mattered, I thought the imports were evaluated

[jakkdl]

Typecheckers evaluate imports, but AST checkers like flake8 usually don't try and just looks at identifiers hoping/assuming they're well-named. (afaik)

Anyway, fixed with #309 - forgot to mention this issue in it.

[cooperlees]

So, is this fine to be closed now?

[jakkdl]

yep!