Typing: return Self in stdlib.BoundLogger

[k4nar]

Summary

Since #642, the BindableLogger protocol says that its methods return Self. But as stdlib.BoundLogger was annotated as returning BoundLogger explicitly, its subclasses where not complying with the BindableLogger protocol.

Example:

import structlog
from structlog.stdlib import BoundLogger


class MyBoundLogger(BoundLogger):
    pass


structlog.configure(
    wrapper_class=MyBoundLogger,
)

Mypy output:

error: Argument "wrapper_class" to "configure" has incompatible type "type[MyBoundLogger]"; expected "type[BindableLogger] | None"  [arg-type]

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[hynek]

thanks!