Description

trivialkettle

opened on Mar 27, 2025

Issue body actions

Bug description:

Hi,
i noticed a regression in python 3.13.2 that the log level has no effect.
I tested the example from https://docs.python.org/3.13/library/logging.html

import logging
logger = logging.getLogger(__name__)

def main():
    logging.basicConfig(filename='myapp.log', level=logging.INFO)
    logger.info('Started')
    logger.info('Finished')

if __name__ == '__main__':
    main()

python3.13 example.py 

but nothing is printed.

CPython versions tested on:

3.13

Operating systems tested on:

Linux

Linked PRs

• gh-131791: Improve speed of textwrap.dedent by replacing re #131792

Activity

1. trivialkettle

   added

   type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

   on Mar 27, 2025
2. graingert commented on Mar 27, 2025

   

   graingert

   on Mar 27, 2025

   Contributor

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   you configured logging.basicConfig(filename='myapp.log', level=logging.INFO) this means nothing will be printed, instead logs will be written to myapp.log
3. ericvsmith commented on Mar 27, 2025

   

   ericvsmith

   on Mar 27, 2025

   Member

   More actions

   As @graingert mentions, the output does show up in the file myapp.log.

   If this is a regression, then in what version of python did it produce output?

   I don't think there's a bug here, but if this did behave differently in a previous version of python that would be interesting.
4. trivialkettle commented on Mar 27, 2025

   

   trivialkettle

   on Mar 27, 2025

   Author

   More actions

   Ah sorry, you are right, I missed this.

   I had some strange issues, that I could not set the logger level, my code works on python 3.10 but not on 3.13.

   basically I do

       logging.basicConfig(stream=sys.stderr, level=args.log, format="%(asctime)s:" + logging.BASIC_FORMAT)
   ...
       class Foo:
           self._logger = logging.getLogger(self.__module__)
   
       def foo():
           self._logger.debug("foo")

   I try to reproduce this, maybe it was a glitch or something.

   Edit: I close it for now until I can reproduce this.
5. trivialkettle

   closed this as completedon Mar 27, 2025
6. ericvsmith

   closed this as not plannedon Mar 27, 2025
7. ericvsmith

   added

   invalid

   and removed

   type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

   on Mar 27, 2025

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