__dunder_blunder___ support

[gitpushdashf]

Hi, everyone!

I'm not sure if this rule would cover this or not: https://beta.ruff.rs/docs/rules/dunder-function-name/

I made a dunder blunder today, with an extra _. Despite ruff, pyright, and pytest, nothing caught my error. It was for a def __lt__()-type function.

This seems fairly trivial, at first glance, at least compared to other rules. Those extra underscores can really blend in with eachother.

If the dunder-function-name does cover it, maybe it could be documented? Or maybe two separate rules would be ideal?

Anyway, Ruff is an awesome project. I don't know if there's an existing Python tool that does this check.

[ngnpope]

This is an interesting one. I've also found mistakes like __lte__() instead of the correct __le__(), etc. which would be good to catch. This might be easily done by having a set of known dunders and comparing. Should be easy enough to do a "Did you mean X?" too.

It's worth noting that Python's enum has some custom dunder methods and it may also be good to extend support for the custom sunder methods too? (I've mistakenly used def __missing__(...): instead of def _missing_(...): before.)

[gitpushdashf]

This is an interesting one. I've also found mistakes like __lte__() instead of the correct __le__(), etc. which would be good to catch. This might be easily done by having a set of known dunders and comparing. Should be easy enough to do a "Did you mean X?" too.

It's worth noting that Python's enum has some custom dunder methods and it may also be good to extend support for the custom sunder methods too? (I've mistakenly used def __missing__(...): instead of def _missing_(...): before.)

Probably! Sunder method mistakes would be good to catch as well.

[charliermarsh]

I think we now support this via bad-dunder-method-name.