When using`--disallow-any-expr`, silence complaints about Any where object would work

Problem

Using Any is not type safe, therefore Mypy provides options to disallow Any. However, there are many uses of Any from third-party and stdlib, so these options tend to result in a lot of errors even when they are not relevant.

I'm finding many situations where I get an error about Any, but the code would be deemed safe if it was object.

Examples

This produces errors about Any on both lines even though the value is not used:

type_hints = typing.get_type_hints(...)  # Dict[str, Any]
if k in type_hints:
    ...

This produces errors as well, but object would not produce errors, as Mypy can infer everything necessary here to be type safe.

origin = typing.get_origin(...)  # Any
if origin is Literal:
    ...
elif origin is list:
    ...

Solution

Add an option, or change the behaviour of the current disallow Any options, such that Any is treated like object. Then, rather than producing errors when Any is present, just show normal errors with Any (as if it was object) in them (e.g. 'Any has no attribute foo').

まず、--disallow-any-expr を付けて2つの例を再現し、それらの診断を同等の object アノテーションと比較します。既存の disallow-Any オプションの扱いを確認し、次に、属性の欠落などの通常のエラーを維持しながら Any を object として扱うためのテストを定義します。