Static typing: Logger.exception() exc_info type does not match Python's built-in one

[rafrafek]

Static type checker used

pyright/pylance

AWS Lambda function runtime

3.11

Powertools for AWS Lambda (Python) version

latest

Static type checker info

Pyright 1.1.331

Code snippet

from aws_lambda_powertools.logging import Logger
logger = Logger(name="%(name)s")
...
ex = Exception()
logger.exception(
    f"Failed to launch workflow: {ex!r}",
    extra=None,
    exc_info=(type(ex), ex, ex.__traceback__),
)

Possible Solution

exc_info should not be bool only, it should be:
"_ExcInfoType" which accepts:

"None"
"bool"
"tuple[type[BaseException], BaseException, TracebackType | None]"
"tuple[None, None, None]"
"BaseException"

[boring-cyborg]

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[rafrafek]

Workaround:

Use logger._logger.exception() instead of logger.exception() to satisfy the static type checker.

[heitorlessa]

hey @rafrafek thanks for spotting yet another one - we must have missed during the review (it was workaround override for the lack of stackframe in 3.8 only in logging.Logger).

Tackling that shortly

[heitorlessa]

I see why this was copied as-is from CPython logging impl: https://github.com/python/cpython/blob/d67f947c72af8a215db2fd285e5de9b1e671fde1/Lib/logging/__init__.py#L1537

[heitorlessa]

Waiting for CI to confirm it won't break previous versions, as I'm unsure when CPython added that typing alias since the exception() implementation don't have it either.