[hirehamir]

Summary

Fixes #20151

I authored the original fix in #19303. This improves that implementation.

Test Plan

I added a new fixture that covers multiple cases from the issue.

crates/ruff_linter/resources/test/fixtures/flake8_logging_format/G004_fix_semantics.py

[astral-sh-bot]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.

[ntBre]

Thanks! This looks reasonable to me overall. I had one request about the tests, and then Codex found a couple of additional edge cases that we should also try to handle:

• Keyword arguments can produce invalid code

   import logging
   
   value = "sample"
   logging.warning(msg=(f"message: {value}"))

  this produces

   logging.warning(msg="message: %s", value)

  with the keyword before the positional argument. I think the result just needs to be parenthesized, like we currently do on main: https://play.ruff.rs/4d6a3c7a-bb6b-4943-b73a-903beef076f7.

• Comments can now be removed in a safe fix

   import logging
   
   value = "sample"
   
   logging.warning(
       (  # Important explanation
           f"message: {value}"
           # Another important explanation
       )
   )

  This is okay overall, we just need to mark the fix unsafe in this case. We can check something like this:

  ruff/crates/ruff_linter/src/rules/flake8_pyi/rules/duplicate_union_member.rs

  Lines 111 to 115 in 17a00de

  	let applicability = if checker.comment_ranges().intersects(expr.range()) {
  	Applicability::Unsafe
  	} else {
  	Applicability::Safe
  	};

  This is one downside of using the generator, though. On main we preserve all the comments: https://play.ruff.rs/833dbeba-42c6-4782-ab5f-e1dedd15e7b8

[hirehamir]

You're welcome! I think adding the parentheses would result in different runtime behavior, but I did implement the other suggestions.

[hirehamir]

@ntBre are there any other changes I should make here?

[ntBre]

Looks good to me, thank you! I just trimmed some of the comments a bit.

[hirehamir]

You're welcome! I'm happy to help.