[ruff] Auto-add r prefix when string has no backslashes for unraw-re-pattern (RUF039)

[dylwil3]

This PR adds a sometimes-available, safe autofix for unraw-re-pattern (RUF039), which prepends an r prefix. It is used only when the string in question has no backslahses (and also does not have a u prefix, since that causes a syntax error.)

Closes #14527

Notes:

• Test fixture unchanged, but snapshot changed to include fix messages.
• This fix is automatically only available in preview since the rule itself is in preview

[MichaReiser]

I don't the we need the performance of memchr here. That's why I would use .contains which is also easier to read

[dylwil3]

Can you help me get a sense of what size strings the performance starts to make a difference? I only mention it because I have seen some long regexes in my life...

But happy to change it to contains!

[MichaReiser]

It's less about the length of a string and more that the fix code isn't a hot path.

I don't have too good a sense for when to use memchr otherwise, beyond what the crate documentation mentions

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

ℹ️ ecosystem check detected linter changes. (+1 -20 violations, +272 -0 fixes in 13 projects; 41 projects unchanged)

RasaHQ/rasa (+0 -0 violations, +4 -0 fixes)

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

- rasa/utils/io.py:222:9: RUF039 First argument to `re.compile()` is not raw string
+ rasa/utils/io.py:222:9: RUF039 [*] First argument to `re.compile()` is not raw string
- rasa/utils/io.py:231:9: RUF039 First argument to `re.compile()` is not raw string
+ rasa/utils/io.py:231:9: RUF039 [*] First argument to `re.compile()` is not raw string

apache/airflow (+0 -0 violations, +64 -0 fixes)

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

- dev/breeze/src/airflow_breeze/params/build_prod_params.py:81:21: RUF039 First argument to `re.match()` is not raw string
+ dev/breeze/src/airflow_breeze/params/build_prod_params.py:81:21: RUF039 [*] First argument to `re.match()` is not raw string
- dev/breeze/src/airflow_breeze/utils/run_tests.py:109:19: RUF039 First argument to `re.sub()` is not raw string
+ dev/breeze/src/airflow_breeze/utils/run_tests.py:109:19: RUF039 [*] First argument to `re.sub()` is not raw string
- dev/perf/dags/elastic_dag.py:73:19: RUF039 First argument to `re.sub()` is not raw string
+ dev/perf/dags/elastic_dag.py:73:19: RUF039 [*] First argument to `re.sub()` is not raw string
- docs/exts/docs_build/lint_checks.py:46:46: RUF039 First argument to `re.findall()` is not raw string
+ docs/exts/docs_build/lint_checks.py:46:46: RUF039 [*] First argument to `re.findall()` is not raw string
- helm_tests/airflow_aux/test_pod_template_file.py:358:26: RUF039 First argument to `re.search()` is not raw string
+ helm_tests/airflow_aux/test_pod_template_file.py:358:26: RUF039 [*] First argument to `re.search()` is not raw string
... 54 additional changes omitted for project

apache/superset (+0 -0 violations, +138 -0 fixes)

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

- RELEASING/changelog.py:276:26: RUF039 First argument to `re.match()` is not raw string
+ RELEASING/changelog.py:276:26: RUF039 [*] First argument to `re.match()` is not raw string
- scripts/build_docker.py:66:23: RUF039 First argument to `re.sub()` is not raw string
+ scripts/build_docker.py:66:23: RUF039 [*] First argument to `re.sub()` is not raw string
- scripts/build_docker.py:68:23: RUF039 First argument to `re.sub()` is not raw string
+ scripts/build_docker.py:68:23: RUF039 [*] First argument to `re.sub()` is not raw string
- scripts/build_docker.py:70:23: RUF039 First argument to `re.sub()` is not raw string
+ scripts/build_docker.py:70:23: RUF039 [*] First argument to `re.sub()` is not raw string
- scripts/build_docker.py:70:51: RUF039 First argument to `re.sub()` is not raw string
+ scripts/build_docker.py:70:51: RUF039 [*] First argument to `re.sub()` is not raw string
- superset/db_engine_specs/athena.py:30:5: RUF039 First argument to `re.compile()` is not raw string
+ superset/db_engine_specs/athena.py:30:5: RUF039 [*] First argument to `re.compile()` is not raw string
- superset/db_engine_specs/bigquery.py:76:5: RUF039 First argument to `re.compile()` is not raw string
+ superset/db_engine_specs/bigquery.py:76:5: RUF039 [*] First argument to `re.compile()` is not raw string
- superset/db_engine_specs/bigquery.py:77:5: RUF039 First argument to `re.compile()` is not raw string
+ superset/db_engine_specs/bigquery.py:77:5: RUF039 [*] First argument to `re.compile()` is not raw string
- superset/db_engine_specs/bigquery.py:90:5: RUF039 First argument to `re.compile()` is not raw string
+ superset/db_engine_specs/bigquery.py:90:5: RUF039 [*] First argument to `re.compile()` is not raw string
- superset/db_engine_specs/denodo.py:29:46: RUF039 First argument to `re.compile()` is not raw string
+ superset/db_engine_specs/denodo.py:29:46: RUF039 [*] First argument to `re.compile()` is not raw string
- superset/db_engine_specs/denodo.py:30:48: RUF039 First argument to `re.compile()` is not raw string
+ superset/db_engine_specs/denodo.py:30:48: RUF039 [*] First argument to `re.compile()` is not raw string
- superset/db_engine_specs/denodo.py:32:9: RUF039 First argument to `re.compile()` is not raw string
... 115 additional changes omitted for project

bokeh/bokeh (+0 -0 violations, +14 -0 fixes)

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

- src/bokeh/util/strings.py:91:19: RUF039 First argument to `re.sub()` is not raw string
+ src/bokeh/util/strings.py:91:19: RUF039 [*] First argument to `re.sub()` is not raw string
- tests/unit/bokeh/io/test_export.py:203:9: RUF039 First argument to `re.compile()` is not raw string
+ tests/unit/bokeh/io/test_export.py:203:9: RUF039 [*] First argument to `re.compile()` is not raw string
- tests/unit/bokeh/io/test_export.py:204:13: RUF039 First argument to `re.compile()` is not raw string
+ tests/unit/bokeh/io/test_export.py:204:13: RUF039 [*] First argument to `re.compile()` is not raw string
- tests/unit/bokeh/io/test_export.py:205:13: RUF039 First argument to `re.compile()` is not raw string
+ tests/unit/bokeh/io/test_export.py:205:13: RUF039 [*] First argument to `re.compile()` is not raw string
- tests/unit/bokeh/io/test_export.py:206:9: RUF039 First argument to `re.compile()` is not raw string
+ tests/unit/bokeh/io/test_export.py:206:9: RUF039 [*] First argument to `re.compile()` is not raw string
... 4 additional changes omitted for project

ibis-project/ibis (+0 -0 violations, +16 -0 fixes)

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

- ibis/backends/__init__.py:1396:17: RUF039 First argument to `re.match()` is not raw string
+ ibis/backends/__init__.py:1396:17: RUF039 [*] First argument to `re.match()` is not raw string
- ibis/backends/flink/__init__.py:320:17: RUF039 First argument to `re.search()` is not raw string
+ ibis/backends/flink/__init__.py:320:17: RUF039 [*] First argument to `re.search()` is not raw string
- ibis/backends/sql/compilers/pyspark.py:362:27: RUF039 First argument to `re.sub()` is not raw string
+ ibis/backends/sql/compilers/pyspark.py:362:27: RUF039 [*] First argument to `re.sub()` is not raw string
- ibis/backends/tests/test_client.py:1047:13: RUF039 First argument to `re.search()` is not raw string
+ ibis/backends/tests/test_client.py:1047:13: RUF039 [*] First argument to `re.search()` is not raw string
- ibis/backends/tests/test_client.py:1068:13: RUF039 First argument to `re.search()` is not raw string
+ ibis/backends/tests/test_client.py:1068:13: RUF039 [*] First argument to `re.search()` is not raw string
... 6 additional changes omitted for project

latchbio/latch (+0 -0 violations, +8 -0 fixes)

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

- src/latch_cli/centromere/ctx.py:464:26: RUF039 First argument to `re.match()` is not raw string
+ src/latch_cli/centromere/ctx.py:464:26: RUF039 [*] First argument to `re.match()` is not raw string
- src/latch_cli/services/init/init.py:309:18: RUF039 First argument to `re.search()` is not raw string
+ src/latch_cli/services/init/init.py:309:18: RUF039 [*] First argument to `re.search()` is not raw string
- src/latch_cli/services/init/init.py:316:18: RUF039 First argument to `re.search()` is not raw string
+ src/latch_cli/services/init/init.py:316:18: RUF039 [*] First argument to `re.search()` is not raw string
- src/latch_cli/services/register/register.py:59:36: RUF039 First argument to `re.compile()` is not raw string
+ src/latch_cli/services/register/register.py:59:36: RUF039 [*] First argument to `re.compile()` is not raw string

lnbits/lnbits (+0 -0 violations, +2 -0 fixes)

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

- lnbits/db.py:151:34: RUF039 First argument to `re.compile()` is not raw string
+ lnbits/db.py:151:34: RUF039 [*] First argument to `re.compile()` is not raw string

pandas-dev/pandas (+0 -7 violations, +0 -0 fixes)

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

- pandas/tests/indexes/datetimes/test_date_range.py:787:29: RUF039 First argument to `re.split()` is not raw string
- pandas/tests/io/formats/style/test_style.py:834:26: RUF039 First argument to `re.findall()` is not raw string
- pandas/tests/io/formats/test_format.py:1115:35: RUF039 First argument to `re.findall()` is not raw string
- pandas/tests/io/test_html.py:477:41: RUF039 First argument to `re.compile()` is not raw string
- pandas/tests/strings/test_find_replace.py:613:22: RUF039 First argument to `re.compile()` is not raw string
- pandas/tests/strings/test_find_replace.py:639:22: RUF039 First argument to `re.compile()` is not raw string
- web/pandas_web.py:99:31: RUF039 First argument to `re.compile()` is not raw string

pypa/build (+0 -0 violations, +4 -0 fixes)

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

- tests/test_integration.py:31:21: RUF039 First argument to `re.compile()` is not raw string
+ tests/test_integration.py:31:21: RUF039 [*] First argument to `re.compile()` is not raw string
- tests/test_integration.py:32:21: RUF039 First argument to `re.compile()` is not raw string
+ tests/test_integration.py:32:21: RUF039 [*] First argument to `re.compile()` is not raw string

python/typeshed (+1 -0 violations, +0 -0 fixes)

ruff check --no-cache --exit-zero --ignore RUF9 --output-format concise --preview --select E,F,FA,I,PYI,RUF,UP,W

+ stdlib/csv.pyi:148:31: W292 No newline at end of file

python-poetry/poetry (+0 -13 violations, +0 -0 fixes)

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

- src/poetry/console/logging/formatters/builder_formatter.py:11:26: RUF039 First argument to `re.sub()` is not raw string
- src/poetry/console/logging/formatters/builder_formatter.py:13:26: RUF039 First argument to `re.sub()` is not raw string
- src/poetry/console/logging/formatters/builder_formatter.py:15:26: RUF039 First argument to `re.sub()` is not raw string
- src/poetry/console/logging/formatters/builder_formatter.py:18:17: RUF039 First argument to `re.sub()` is not raw string
- src/poetry/mixology/solutions/providers/python_requirement_solution_provider.py:22:13: RUF039 First argument to `re.match()` is not raw string
- src/poetry/mixology/solutions/providers/python_requirement_solution_provider.py:23:13: RUF039 First argument to `re.match()` is not raw string
- src/poetry/utils/dependency_specification.py:192:13: RUF039 First argument to `re.sub()` is not raw string
- tests/conftest.py:378:20: RUF039 First argument to `re.compile()` is not raw string
- tests/installation/conftest.py:43:20: RUF039 First argument to `re.compile()` is not raw string
- tests/installation/test_chooser.py:108:20: RUF039 First argument to `re.compile()` is not raw string
... 3 additional changes omitted for project

... Truncated remaining completed project reports due to GitHub comment length restrictions

Changes by rule (2 rules affected)

code	total	+ violation	- violation	+ fix	- fix
RUF039	292	0	20	272	0
W292	1	1	0	0	0

[MichaReiser]

Can you manually run your change on the poetry repo. I suspect that it panics and that this is the reason why we see fewer violations

[dylwil3]

Can you manually run your change on the poetry repo. I suspect that it panics and that this is the reason why we see fewer violations

Good catch, will do!

[MichaReiser]

Or is this the same as with TC006 that both poetry and panda set fix = true.

[dylwil3]

Or is this the same as with TC006 that both poetry and panda set fix = true.

Yep it's that, just checked!