ruff/crates
Dan Parizher 1fd852fb3f
[ruff] Ignore str() when not used for simple conversion (RUF065) (#21330)
## Summary

Fixed RUF065 (`logging-eager-conversion`) to only flag `str()` calls
when they perform a simple conversion that can be safely removed. The
rule now ignores `str()` calls with no arguments, multiple arguments,
starred arguments, or keyword unpacking, preventing false positives.

Fixes #21315

## Problem Analysis

The RUF065 rule was incorrectly flagging all `str()` calls in logging
statements, even when `str()` was performing actual conversion work
beyond simple type coercion. Specifically, the rule flagged:

- `str()` with no arguments - which returns an empty string
- `str(b"data", "utf-8")` with multiple arguments - which performs
encoding conversion
- `str(*args)` with starred arguments - which unpacks arguments
- `str(**kwargs)` with keyword unpacking - which passes keyword
arguments

These cases cannot be safely removed because `str()` is doing meaningful
work (encoding conversion, argument unpacking, etc.), not just redundant
type conversion.

The root cause was that the rule only checked if the function was
`str()` without validating the call signature. It didn't distinguish
between simple `str(value)` conversions (which can be removed) and more
complex `str()` calls that perform actual work.

## Approach

The fix adds validation to the `str()` detection logic in
`logging_eager_conversion.rs`:

1. **Check argument count**: Only flag `str()` calls with exactly one
positional argument (`str_call_args.args.len() == 1`)
2. **Check for starred arguments**: Ensure the single argument is not
starred (`!str_call_args.args[0].is_starred_expr()`)
3. **Check for keyword arguments**: Ensure there are no keyword
arguments (`str_call_args.keywords.is_empty()`)

This ensures the rule only flags cases like `str(value)` where `str()`
is truly redundant and can be removed, while ignoring cases where
`str()` performs actual conversion work.

The fix maintains backward compatibility - all existing valid test cases
continue to be flagged correctly, while the new edge cases are properly
ignored.

---------

Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
2025-11-10 18:04:41 -05:00
..
ruff Add upstream linter URL to ruff linter --output-format=json (#21316) 2025-11-10 10:42:09 +01:00
ruff_annotate_snippets Display diffs for ruff format --check and add support for different output formats (#20443) 2025-09-30 12:00:51 -04:00
ruff_benchmark [ty] Update expected diagnostic count in benchmarks (#21269) 2025-11-04 03:18:12 +00:00
ruff_cache
ruff_db [ty] Smaller refactors to server API in prep for notebook support (#21095) 2025-10-31 20:00:04 +00:00
ruff_dev Update Rust toolchain to 1.91 (#21179) 2025-11-01 01:50:58 +00:00
ruff_diagnostics
ruff_formatter [ty] Use "cannot" consistently over "can not" (#21255) 2025-11-03 10:38:20 -05:00
ruff_graph [ruff]: Make ruff analyze graph work with jupyter notebooks (#21161) 2025-10-31 21:47:01 +00:00
ruff_index
ruff_linter [ruff] Ignore str() when not used for simple conversion (RUF065) (#21330) 2025-11-10 18:04:41 -05:00
ruff_macros Document when a rule was added (#21035) 2025-10-23 14:48:41 -04:00
ruff_memory_usage [ty] Clean up inherited generic contexts (#20647) 2025-10-03 13:55:43 -04:00
ruff_notebook Display diffs for ruff format --check and add support for different output formats (#20443) 2025-09-30 12:00:51 -04:00
ruff_options_metadata
ruff_python_ast [ruff] Ignore str() when not used for simple conversion (RUF065) (#21330) 2025-11-10 18:04:41 -05:00
ruff_python_ast_integration_tests
ruff_python_codegen Configurable "unparse mode" for ruff_python_codegen::Generator (#21041) 2025-10-24 15:44:48 +00:00
ruff_python_formatter Avoid extra parentheses for long match patterns with as captures (#21176) 2025-11-03 17:06:52 -05:00
ruff_python_importer [ruff] Add API for splicing into an existing import statement 2025-09-17 13:59:28 -04:00
ruff_python_index
ruff_python_literal
ruff_python_parser Fix syntax error false positive on alternative match patterns (#21362) 2025-11-10 10:51:51 -05:00
ruff_python_semantic [pyflakes] Revert to stable behavior if imports for module lie in alternate branches for F401 (#20878) 2025-10-27 10:23:36 -05:00
ruff_python_stdlib [ruff] Extend FA102 with listed PEP 585-compatible APIs (#20659) 2025-10-03 09:45:32 -04:00
ruff_python_trivia Handle t-string prefixes in SimpleTokenizer (#20578) 2025-09-25 14:33:37 -05:00
ruff_python_trivia_integration_tests Handle t-string prefixes in SimpleTokenizer (#20578) 2025-09-25 14:33:37 -05:00
ruff_server Fix missing diagnostics for notebooks (#21156) 2025-10-31 01:16:43 +00:00
ruff_source_file
ruff_text_size [ruff] Update schemars to v1 (#20942) 2025-10-20 08:59:52 +02:00
ruff_wasm Bump 0.14.4 (#21306) 2025-11-06 15:47:29 -06:00
ruff_workspace [configuration] Fix unclear error messages for line-length values exceeding u16::MAX (#21329) 2025-11-10 18:29:35 +00:00
ty [ty] implement typing.NewType by adding Type::NewTypeInstance 2025-11-10 14:55:47 -08:00
ty_combine
ty_completion_eval [ty] Favour imported symbols over builtin symbols (#21285) 2025-11-06 06:46:08 -05:00
ty_ide [ty] implement typing.NewType by adding Type::NewTypeInstance 2025-11-10 14:55:47 -08:00
ty_project [ty] Fix --exclude and src.exclude merging (#21341) 2025-11-10 12:52:45 +01:00
ty_python_semantic [ty] implement typing.NewType by adding Type::NewTypeInstance 2025-11-10 14:55:47 -08:00
ty_server [ty] implement typing.NewType by adding Type::NewTypeInstance 2025-11-10 14:55:47 -08:00
ty_static [ty] improve base conda distinction from child conda (#20675) 2025-10-03 13:56:06 +00:00
ty_test [ty] Fix bug where ty would think all types had an __mro__ attribute (#20995) 2025-10-27 11:19:12 +00:00
ty_vendored [ty] Constraining a typevar with itself (possibly via union or intersection) (#21273) 2025-11-05 12:31:53 -05:00
ty_wasm [ruff,ty] Enable tracing's log feature 2025-10-03 08:18:03 -04:00