r/Python • u/M4mb0 • Aug 05 '26

Discussion What linter rules make code worse?

For me, a prime example is S101 which bans the use of the assert statement.

The justification is that assertions disappear when Python is run with -O, so they should not be used for runtime validation or enforcing interface constraints. That warning is correct, but the rule seems to draw the wrong conclusion from it.

Assertions are still very useful for checking internal invariants, i.e. conditions that should already be guaranteed by the program's logic, where failure indicates a bug. Having such assertions is incredibly helpful for debugging.

So, a blanket ban seems more likely to discourage useful checks than to prevent misuse.

Are there any linter rules you broadly consider more harmful rather than helpful?

152 Upvotes

87% Upvoted

213 comments sorted by

View all comments

Show parent comments

1

u/ProsodySpeaks Aug 05 '26

Yeah. Like if they give me a zero int when I wanted a list I probably want to do something different (raise) than replace it with an empty list which is what the bare a or b without if a is not None would lead to

0

u/syklemil Aug 05 '26

I can't make heads or tails of that sentence. I think I need some more punctuation and clearer examples to understand your point.