log-exception-outside-except-handler (LOG004)

Derived from the flake8-logging linter.

Fix is sometimes available.

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

What it does

Checks for .exception() logging calls outside of exception handlers.

Why is this bad?

The documentation states:

This function should only be called from an exception handler.

Calling .exception() outside of an exception handler attaches None as exception information, leading to confusing messages:

>>> logging.exception("example")
ERROR:root:example
NoneType: None

Example

import logging

logging.exception("Foobar")

Use instead:

import logging

logging.error("Foobar")

Fix safety

The fix, if available, will always be marked as unsafe, as it changes runtime behavior.