meta-class-abc-meta (FURB180)

Derived from the refurb linter.

Fix is always available.

This rule is unstable and in preview. The --preview flag is required for use.

What it does

Checks for uses of metaclass=abc.ABCMeta to define abstract base classes (ABCs).

Why is this bad?

Instead of class C(metaclass=abc.ABCMeta): ..., use class C(ABC): ... to define an abstract base class. Inheriting from the ABC wrapper class is semantically identical to setting metaclass=abc.ABCMeta, but more succinct.

Example

class C(metaclass=ABCMeta):
    pass

Use instead:

class C(ABC):
    pass

References

• Python documentation: abc.ABC
• Python documentation: abc.ABCMeta