Ignore builtins when detecting missing f-strings

[charliermarsh]

Summary

Reported on Discord: if the name maps to a builtin, it's not bound locally, so is very unlikely to be intended as an f-string expression.

[ThiefMaster]

Some real code to test against (I think in all 3 cases it was triggered because of builtins):

• https://github.com/indico/indico/blob/c4e45df45639efd6744307780189c4a3d9b134a5/indico/web/forms/validators.py#L346-L357
• https://github.com/indico/indico/blob/c4e45df45639efd6744307780189c4a3d9b134a5/indico/modules/events/management/program_codes.py#L50
• https://github.com/indico/indico/blob/c4e45df45639efd6744307780189c4a3d9b134a5/indico/util/mdx_latex.py#L394

Errors with the current stable release:

[adrian@eluvian:~/dev/indico/py3/src:master $]> ruff check --select RUF027
indico/modules/events/management/program_codes.py:50:21: RUF027 Possible f-string without an `f` prefix
indico/util/mdx_latex.py:393:23: RUF027 Possible f-string without an `f` prefix
indico/web/forms/validators.py:350:36: RUF027 Possible f-string without an `f` prefix
indico/web/forms/validators.py:351:36: RUF027 Possible f-string without an `f` prefix
indico/web/forms/validators.py:353:36: RUF027 Possible f-string without an `f` prefix
indico/web/forms/validators.py:354:36: RUF027 Possible f-string without an `f` prefix
indico/web/forms/validators.py:356:29: RUF027 Possible f-string without an `f` prefix
Found 7 errors.
No fixes available (7 hidden fixes can be enabled with the `--unsafe-fixes` option).

[charliermarsh]

I think we should also ignore ngettext calls as you mention, but this would've prevented those false positives 👍

[github-actions]

ruff-ecosystem results

Linter (stable)

ℹ️ ecosystem check encountered linter errors. (no lint changes; 1 project error)

sphinx-doc/sphinx (error)

ruff failed
  Cause: Selection of unstable rules without the `--preview` flag is not allowed. Enable preview or remove selection of:
	- FURB113
	- FURB131
	- FURB132

Linter (preview)

ℹ️ ecosystem check detected linter changes. (+0 -36 violations, +0 -0 fixes in 2 projects; 41 projects unchanged)

pandas-dev/pandas (+0 -2 violations, +0 -0 fixes)

ruff check --no-cache --exit-zero --ignore RUF9 --output-format concise --preview

- pandas/tests/indexes/base_class/test_formats.py:138:35: RUF027 Possible f-string without an `f` prefix
- pandas/tests/indexes/base_class/test_formats.py:141:16: RUF027 Possible f-string without an `f` prefix

zulip/zulip (+0 -34 violations, +0 -0 fixes)

ruff check --no-cache --exit-zero --ignore RUF9 --output-format concise --preview --select ALL

- zerver/management/commands/edit_linkifiers.py:14:12: RUF027 Possible f-string without an `f` prefix
- zerver/migrations/0423_fix_email_gateway_attachment_owner.py:93:21: RUF027 Possible f-string without an `f` prefix
- zerver/openapi/curl_param_value_generators.py:281:9: RUF027 Possible f-string without an `f` prefix
- zerver/openapi/python_examples.py:454:25: RUF027 Possible f-string without an `f` prefix
- zerver/openapi/python_examples.py:469:25: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_audit_log.py:914:26: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_audit_log.py:974:29: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_event_system.py:762:29: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_events.py:2747:15: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_markdown.py:2506:24: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_markdown.py:2604:24: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_markdown.py:2892:24: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_markdown.py:2962:24: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_message_dict.py:246:24: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:101:32: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:134:32: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:164:29: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:180:29: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:186:29: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:203:29: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:216:32: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:24:29: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:319:33: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:323:33: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:327:33: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:37:48: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:63:32: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:69:32: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:75:32: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:82:13: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:89:32: RUF027 Possible f-string without an `f` prefix
- zerver/tests/test_realm_linkifiers.py:95:32: RUF027 Possible f-string without an `f` prefix
- zilencer/management/commands/populate_db.py:832:17: RUF027 Possible f-string without an `f` prefix
- zilencer/management/commands/populate_db.py:838:17: RUF027 Possible f-string without an `f` prefix

Changes by rule (1 rules affected)

code	total	+ violation	- violation	+ fix	- fix
RUF027	36	0	36	0	0

[charliermarsh]

Ecosystem checks look like improvements to me.

[snowsignal]

Looks good to me! I'm really happy to see fewer false positives in the ecosystem check.