UP011 is incorrectly replacing lru_cache(max_size)=None

[henribru]

The UP011 rule replaces functools.lru_cache(max_size=None) with functools.lru_cache. The corresponding rule in pyupgrade replaces it with functools.cache: https://github.com/asottile/pyupgrade#replace-functoolslru_cachemaxsizenone-with-shorthand.

Tested with ruff 0.0.222

[charliermarsh]

Thank you! Fixing now. Just an oversight.

[henribru]

@charliermarsh Thanks for the super quick response! Your fix seems to work fine for the @functools.lru_cache(max_size=None) case, but there's still a slight issue if you do from functools import lru_cache and then @lru_cache(max_size=None). In that case it doesn't auto-fix anything, but it still suggests "Remove unnecessary parameters"

[charliermarsh]

@henribru - Yeah this is a known limitation (and pyupgrade doesn't fix that case either, IIRC). In that case, we actually need to modify the import too, to include cache. So for now, we flag it, but can't fix it.

Another case of #835.

[henribru]

@charliermarsh That's a fair limitation, but still the message is pretty misleading since it's telling you to remove the parameters instead of changing lru_cache to cache. Since just removing max_size=None changes the behavior, it's not "unnecessary"

[henribru]

Note that pyupgrade separates this into two rules, one that converts lru_cache() into lru_cache and one that converts lru_cache(max_size=None) into cache. The current error message works for the first case, but it seems misleading for the second

[charliermarsh]

Ah right -- I'll modify the error message.

[charliermarsh]

(And consider splitting into two rules, too.)

[charliermarsh]

Fixed in #1938.

[henribru]

Thanks again for all your hard work, I really appreciate it!

[charliermarsh]

Thanks for being persistent on this one even after I closed it out -- you were totally right!