ruff/changelogs/0.12.x.md
2025-09-10 12:11:22 -04:00

40 KiB

Changelog 0.12.x

0.12.0

Check out the blog post for a migration guide and overview of the changes!

Breaking changes

  • Detection of more syntax errors

    Ruff now detects version-related syntax errors, such as the use of the match statement on Python versions before 3.10, and syntax errors emitted by CPython's compiler, such as irrefutable match patterns before the final case arm.

  • New default Python version handling for syntax errors

    Ruff will default to the latest supported Python version (3.13) when checking for the version-related syntax errors mentioned above to prevent false positives in projects without a Python version configured. The default in all other cases, like applying lint rules, is unchanged and remains at the minimum supported Python version (3.9).

  • Updated f-string formatting

    Ruff now formats multi-line f-strings with format specifiers to avoid adding a line break after the format specifier. This addresses a change to the Python grammar in version 3.13.4 that made such a line break a syntax error.

  • rust-toolchain.toml is no longer included in source distributions

    The rust-toolchain.toml is used to specify a higher Rust version than Ruff's minimum supported Rust version (MSRV) for development and building release artifacts. However, when present in source distributions, it would also cause downstream package maintainers to pull in the same Rust toolchain, even if their available toolchain was MSRV-compatible.

Removed Rules

The following rules have been removed:

Deprecated Rules

The following rules have been deprecated:

Stabilization

The following rules have been stabilized and are no longer in preview:

The following behaviors have been stabilized:

Preview features

  • [ruff] Check for non-context-manager use of pytest.raises, pytest.warns, and pytest.deprecated_call (RUF061) (#17368)
  • [syntax-errors] Raise unsupported syntax error for template strings prior to Python 3.14 (#18664)

Bug fixes

  • Add syntax error when conversion flag does not immediately follow exclamation mark (#18706)
  • Add trailing space around readlines (#18542)
  • Fix \r and \r\n handling in t- and f-string debug texts (#18673)
  • Hug closing } when f-string expression has a format specifier (#18704)
  • [flake8-pyi] Avoid syntax error in the case of starred and keyword arguments (PYI059) (#18611)
  • [flake8-return] Fix RET504 autofix generating a syntax error (#18428)
  • [pep8-naming] Suppress fix for N804 and N805 if the recommended name is already used (#18472)
  • [pycodestyle] Avoid causing a syntax error in expressions spanning multiple lines (E731) (#18479)
  • [pyupgrade] Suppress UP008 if super is shadowed (#18688)
  • [refurb] Parenthesize lambda and ternary expressions (FURB122, FURB142) (#18592)
  • [ruff] Handle extra arguments to deque (RUF037) (#18614)
  • [ruff] Preserve parentheses around deque in fix for unnecessary-empty-iterable-within-deque-call (RUF037) (#18598)
  • [ruff] Validate arguments before offering a fix (RUF056) (#18631)
  • [ruff] Skip fix for RUF059 if dummy name is already bound (#18509)
  • [pylint] Fix PLW0128 to check assignment targets in square brackets and after asterisks (#18665)

Rule changes

  • Fix false positive on mutations in return statements (B909) (#18408)
  • Treat ty: comments as pragma comments (#18532)
  • [flake8-pyi] Apply custom-typevar-for-self to string annotations (PYI019) (#18311)
  • [pyupgrade] Don't offer a fix for Optional[None] (UP007, UP045) (#18545)
  • [pyupgrade] Fix super(__class__, self) detection (UP008) (#18478)
  • [refurb] Make the fix for FURB163 unsafe for log2, log10, *args, and deleted comments (#18645)

Server

  • Support cancellation requests (#18627)

Documentation

  • Drop confusing second * from glob pattern example for per-file-target-version (#18709)
  • Update Neovim configuration examples (#18491)
  • [pylint] De-emphasize __hash__ = Parent.__hash__ (PLW1641) (#18613)
  • [refurb] Add a note about float literal handling (FURB157) (#18615)

0.12.1

Preview features

  • [flake8-errmsg] Extend EM101 to support byte strings (#18867)
  • [flake8-use-pathlib] Add autofix for PTH202 (#18763)
  • [pygrep-hooks] Add AsyncMock methods to invalid-mock-access (PGH005) (#18547)
  • [pylint] Ignore __init__.py files in (PLC0414) (#18400)
  • [ruff] Trigger RUF037 for empty string and byte strings (#18862)
  • [formatter] Fix missing blank lines before decorated classes in .pyi files (#18888)

Bug fixes

  • Avoid generating diagnostics with per-file ignores (#18801)
  • Handle parenthesized arguments in remove_argument (#18805)
  • [flake8-logging] Avoid false positive for exc_info=True outside logger.exception (LOG014) (#18737)
  • [flake8-pytest-style] Enforce pytest import for decorators (#18779)
  • [flake8-pytest-style] Mark autofix for PT001 and PT023 as unsafe if there's comments in the decorator (#18792)
  • [flake8-pytest-style] PT001/PT023 fix makes syntax error on parenthesized decorator (#18782)
  • [flake8-raise] Make fix unsafe if it deletes comments (RSE102) (#18788)
  • [flake8-simplify] Fix SIM911 autofix creating a syntax error (#18793)
  • [flake8-simplify] Fix false negatives for shadowed bindings (SIM910, SIM911) (#18794)
  • [flake8-simplify] Preserve original behavior for except () and bare except (SIM105) (#18213)
  • [flake8-pyi] Fix PYI041's fix causing TypeError with None | None | ... (#18637)
  • [perflint] Fix PERF101 autofix creating a syntax error and mark autofix as unsafe if there are comments in the list call expr (#18803)
  • [perflint] Fix false negative in PERF401 (#18866)
  • [pylint] Avoid flattening nested min/max when outer call has single argument (PLW3301) (#16885)
  • [pylint] Fix PLC2801 autofix creating a syntax error (#18857)
  • [pylint] Mark PLE0241 autofix as unsafe if there's comments in the base classes (#18832)
  • [pylint] Suppress PLE2510/PLE2512/PLE2513/PLE2514/PLE2515 autofix if the text contains an odd number of backslashes (#18856)
  • [refurb] Detect more exotic float literals in FURB164 (#18925)
  • [refurb] Fix FURB163 autofix creating a syntax error for yield expressions (#18756)
  • [refurb] Mark FURB129 autofix as unsafe if there's comments in the readlines call (#18858)
  • [ruff] Fix false positives and negatives in RUF010 (#18690)
  • Fix casing of analyze.direction variant names (#18892)

Rule changes

  • Fix f-string interpolation escaping in generated fixes (#18882)
  • [flake8-return] Mark RET501 fix unsafe if comments are inside (#18780)
  • [flake8-async] Fix detection for large integer sleep durations in ASYNC116 rule (#18767)
  • [flake8-async] Mark autofix for ASYNC115 as unsafe if the call expression contains comments (#18753)
  • [flake8-bugbear] Mark autofix for B004 as unsafe if the hasattr call expr contains comments (#18755)
  • [flake8-comprehension] Mark autofix for C420 as unsafe if there's comments inside the dict comprehension (#18768)
  • [flake8-comprehensions] Handle template strings for comprehension fixes (#18710)
  • [flake8-future-annotations] Add autofix (FA100) (#18903)
  • [pyflakes] Mark F504/F522/F523 autofix as unsafe if there's a call with side effect (#18839)
  • [pylint] Allow fix with comments and document performance implications (PLW3301) (#18936)
  • [pylint] Detect more exotic NaN literals in PLW0177 (#18630)
  • [pylint] Fix PLC1802 autofix creating a syntax error and mark autofix as unsafe if there's comments in the len call (#18836)
  • [pyupgrade] Extend version detection to include sys.version_info.major (UP036) (#18633)
  • [ruff] Add lint rule RUF064 for calling chmod with non-octal integers (#18541)
  • [ruff] Added cls.__dict__.get('__annotations__') check (RUF063) (#18233)
  • [ruff] Frozen dataclass default should be valid (RUF009) (#18735)

Server

  • Consider virtual path for various server actions (#18910)

Documentation

  • Add fix safety sections (#18940,#18841,#18802,#18837,#18800,#18415,#18853,#18842)
  • Use updated pre-commit id (#18718)
  • [perflint] Small docs improvement to PERF401 (#18786)
  • [pyupgrade]: Use super(), not __super__ in error messages (UP008) (#18743)
  • [flake8-pie] Small docs fix to PIE794 (#18829)
  • [flake8-pyi] Correct collections-named-tuple example to use PascalCase assignment (#16884)
  • [flake8-pie] Add note on type checking benefits to unnecessary-dict-kwargs (PIE804) (#18666)
  • [pycodestyle] Clarify PEP 8 relationship to whitespace-around-operator rules (#18870)

Other changes

  • Disallow newlines in format specifiers of single quoted f- or t-strings (#18708)
  • [flake8-logging] Add fix safety section to LOG002 (#18840)
  • [pyupgrade] Add fix safety section to UP010 (#18838)

0.12.2

Preview features

  • [flake8-pyi] Expand Optional[A] to A | None (PYI016) (#18572)
  • [pyupgrade] Mark UP008 fix safe if no comments are in range (#18683)

Bug fixes

  • [flake8-comprehensions] Fix C420 to prepend whitespace when needed (#18616)
  • [perflint] Fix PERF403 panic on attribute or subscription loop variable (#19042)
  • [pydocstyle] Fix D413 infinite loop for parenthesized docstring (#18930)
  • [pylint] Fix PLW0108 autofix introducing a syntax error when the lambda's body contains an assignment expression (#18678)
  • [refurb] Fix false positive on empty tuples (FURB168) (#19058)
  • [ruff] Allow more field calls from attrs (RUF009) (#19021)
  • [ruff] Fix syntax error introduced for an empty string followed by a u-prefixed string (UP025) (#18899)

Rule changes

  • [flake8-executable] Allow uvx in shebang line (EXE003) (#18967)
  • [pandas] Avoid flagging PD002 if pandas is not imported (#18963)
  • [pyupgrade] Avoid PEP-604 unions with typing.NamedTuple (UP007, UP045) (#18682)

Documentation

  • Document link between import-outside-top-level (PLC0415) and lint.flake8-tidy-imports.banned-module-level-imports (#18733)
  • Fix description of the format.skip-magic-trailing-comma example (#19095)
  • [airflow] Make AIR302 example error out-of-the-box (#18988)
  • [airflow] Make AIR312 example error out-of-the-box (#18989)
  • [flake8-annotations] Make ANN401 example error out-of-the-box (#18974)
  • [flake8-async] Make ASYNC100 example error out-of-the-box (#18993)
  • [flake8-async] Make ASYNC105 example error out-of-the-box (#19002)
  • [flake8-async] Make ASYNC110 example error out-of-the-box (#18975)
  • [flake8-async] Make ASYNC210 example error out-of-the-box (#18977)
  • [flake8-async] Make ASYNC220, ASYNC221, and ASYNC222 examples error out-of-the-box (#18978)
  • [flake8-async] Make ASYNC251 example error out-of-the-box (#18990)
  • [flake8-bandit] Make S201 example error out-of-the-box (#19017)
  • [flake8-bandit] Make S604 and S609 examples error out-of-the-box (#19049)
  • [flake8-bugbear] Make B028 example error out-of-the-box (#19054)
  • [flake8-bugbear] Make B911 example error out-of-the-box (#19051)
  • [flake8-datetimez] Make DTZ011 example error out-of-the-box (#19055)
  • [flake8-datetimez] Make DTZ901 example error out-of-the-box (#19056)
  • [flake8-pyi] Make PYI032 example error out-of-the-box (#19061)
  • [flake8-pyi] Make example error out-of-the-box (PYI014, PYI015) (#19097)
  • [flake8-pyi] Make example error out-of-the-box (PYI042) (#19101)
  • [flake8-pyi] Make example error out-of-the-box (PYI059) (#19080)
  • [flake8-pyi] Make example error out-of-the-box (PYI062) (#19079)
  • [flake8-pytest-style] Make example error out-of-the-box (PT023) (#19104)
  • [flake8-pytest-style] Make example error out-of-the-box (PT030) (#19105)
  • [flake8-quotes] Make example error out-of-the-box (Q003) (#19106)
  • [flake8-simplify] Make example error out-of-the-box (SIM110) (#19113)
  • [flake8-simplify] Make example error out-of-the-box (SIM113) (#19109)
  • [flake8-simplify] Make example error out-of-the-box (SIM401) (#19110)
  • [pyflakes] Fix backslash in docs (F621) (#19098)
  • [pylint] Fix PLC0415 example (#18970)

0.12.3

Preview features

  • [flake8-bugbear] Support non-context-manager calls in B017 (#19063)
  • [flake8-use-pathlib] Add autofixes for PTH100, PTH106, PTH107, PTH108, PTH110, PTH111, PTH112, PTH113, PTH114, PTH115, PTH117, PTH119, PTH120 (#19213)
  • [flake8-use-pathlib] Add autofixes for PTH203, PTH204, PTH205 (#18922)

Bug fixes

  • [flake8-return] Fix false-positive for variables used inside nested functions in RET504 (#18433)
  • Treat form feed as valid whitespace before a line continuation (#19220)
  • [flake8-type-checking] Fix syntax error introduced by fix (TC008) (#19150)
  • [pyupgrade] Keyword arguments in super should suppress the UP008 fix (#19131)

Documentation

  • [flake8-pyi] Make example error out-of-the-box (PYI007, PYI008) (#19103)
  • [flake8-simplify] Make example error out-of-the-box (SIM116) (#19111)
  • [flake8-type-checking] Make example error out-of-the-box (TC001) (#19151)
  • [flake8-use-pathlib] Make example error out-of-the-box (PTH210) (#19189)
  • [pycodestyle] Make example error out-of-the-box (E272) (#19191)
  • [pycodestyle] Make example not raise unnecessary SyntaxError (E114) (#19190)
  • [pydoclint] Make example error out-of-the-box (DOC501) (#19218)
  • [pylint, pyupgrade] Fix syntax errors in examples (PLW1501, UP028) (#19127)
  • [pylint] Update missing-maxsplit-arg docs and error to suggest proper usage (PLC0207) (#18949)
  • [flake8-bandit] Make example error out-of-the-box (S412) (#19241)

0.12.4

Preview features

  • [flake8-type-checking, pyupgrade, ruff] Add from __future__ import annotations when it would allow new fixes (TC001, TC002, TC003, UP037, RUF013) (#19100)
  • [flake8-use-pathlib] Add autofix for PTH109 (#19245)
  • [pylint] Detect indirect pathlib.Path usages for unspecified-encoding (PLW1514) (#19304)

Bug fixes

  • [flake8-bugbear] Fix B017 false negatives for keyword exception arguments (#19217)
  • [flake8-use-pathlib] Fix false negative on direct Path() instantiation (PTH210) (#19388)
  • [flake8-django] Fix DJ008 false positive for abstract models with type-annotated abstract field (#19221)
  • [isort] Fix I002 import insertion after docstring with multiple string statements (#19222)
  • [isort] Treat form feed as valid whitespace before a semicolon (#19343)
  • [pydoclint] Fix SyntaxError from fixes with line continuations (D201, D202) (#19246)
  • [refurb] FURB164 fix should validate arguments and should usually be marked unsafe (#19136)

Rule changes

  • [flake8-use-pathlib] Skip single dots for invalid-pathlib-with-suffix (PTH210) on versions >= 3.14 (#19331)
  • [pep8_naming] Avoid false positives on standard library functions with uppercase names (N802) (#18907)
  • [pycodestyle] Handle brace escapes for t-strings in logical lines (#19358)
  • [pylint] Extend invalid string character rules to include t-strings (#19355)
  • [ruff] Allow strict kwarg when checking for starmap-zip (RUF058) in Python 3.14+ (#19333)

Documentation

0.12.5

Preview features

  • [flake8-use-pathlib] Add autofix for PTH101, PTH104, PTH105, PTH121 (#19404)
  • [ruff] Support byte strings (RUF055) (#18926)

Bug fixes

  • Fix unreachable panic in parser (#19183)
  • [flake8-pyi] Skip fix if all Union members are None (PYI016) (#19416)
  • [perflint] Parenthesize generator expressions (PERF401) (#19325)
  • [pylint] Handle empty comments after line continuation (PLR2044) (#19405)

Rule changes

  • [pep8-naming] Fix N802 false positives for CGIHTTPRequestHandler and SimpleHTTPRequestHandler (#19432)

0.12.6

Preview features

  • [flake8-commas] Add support for trailing comma checks in type parameter lists (COM812, COM819) (#19390)
  • [pylint] Implement auto-fix for missing-maxsplit-arg (PLC0207) (#19387)
  • [ruff] Offer fixes for RUF039 in more cases (#19065)

Bug fixes

  • Support .pyi files in ruff analyze graph (#19611)
  • [flake8-pyi] Preserve inline comment in ellipsis removal (PYI013) (#19399)
  • [perflint] Ignore rule if target is global or nonlocal (PERF401) (#19539)
  • [pyupgrade] Fix UP030 to avoid modifying double curly braces in format strings (#19378)
  • [refurb] Ignore decorated functions for FURB118 (#19339)
  • [refurb] Mark int and bool cases for Decimal.from_float as safe fixes (FURB164) (#19468)
  • [ruff] Fix RUF033 for named default expressions (#19115)

Rule changes

  • [flake8-blind-except] Change BLE001 to permit logging.critical(..., exc_info=True) (#19520)

Performance

  • Add support for specifying minimum dots in detected string imports (#19538)

0.12.7

This is a follow-up release to 0.12.6. Because of an issue in the package metadata, 0.12.6 failed to publish fully to PyPI and has been yanked. Similarly, there is no GitHub release or Git tag for 0.12.6. The contents of the 0.12.7 release are identical to 0.12.6, except for the updated metadata.

0.12.8

Preview features

  • [flake8-use-pathlib] Expand PTH201 to check all PurePath subclasses (#19440)

Bug fixes

  • [flake8-blind-except] Change BLE001 to correctly parse exception tuples (#19747)
  • [flake8-errmsg] Exclude typing.cast from EM101 (#19656)
  • [flake8-simplify] Fix raw string handling in SIM905 for embedded quotes (#19591)
  • [flake8-import-conventions] Avoid false positives for NFKC-normalized __debug__ import aliases in ICN001 (#19411)
  • [isort] Fix syntax error after docstring ending with backslash (I002) (#19505)
  • [pylint] Mark PLC0207 fixes as unsafe when *args unpacking is present (#19679)
  • [pyupgrade] Prevent infinite loop with I002 (UP010, UP035) (#19413)
  • [ruff] Parenthesize generator expressions in f-strings (RUF010) (#19434)

Rule changes

  • [eradicate] Don't flag pyrefly pragmas as unused code (ERA001) (#19731)

Documentation

  • Replace "associative" with "commutative" in docs for RUF036 (#19706)
  • Fix copy and line separator colors in dark mode (#19630)
  • Fix link to typing documentation (#19648)
  • [refurb] Make more examples error out-of-the-box (#19695,#19673,#19672)

Other changes

  • Include column numbers in GitLab output format (#19708)
  • Always expand tabs to four spaces in diagnostics (#19618)
  • Update pre-commit's ruff id (#19654)

0.12.9

Preview features

  • [airflow] Add check for airflow.secrets.cache.SecretCache (AIR301) (#17707)
  • [ruff] Offer a safe fix for multi-digit zeros (RUF064) (#19847)

Bug fixes

  • [flake8-blind-except] Fix BLE001 false-positive on raise ... from None (#19755)
  • [flake8-comprehensions] Fix false positive for C420 with attribute, subscript, or slice assignment targets (#19513)
  • [flake8-simplify] Fix handling of U+001C..U+001F whitespace (SIM905) (#19849)

Rule changes

  • [pylint] Use lowercase hex characters to match the formatter (PLE2513) (#19808)

Documentation

  • Fix lint.future-annotations link (#19876)

Other changes

  • Build riscv64 binaries for release (#19819)

  • Add rule code to error description in GitLab output (#19896)

  • Improve rendering of the full output format (#19415)

    Below is an example diff for F401:

    -unused.py:8:19: F401 [*] `pathlib` imported but unused
    +F401 [*] `pathlib` imported but unused
    +  --> unused.py:8:19
        |
      7 | # Unused, _not_ marked as required (due to the alias).
      8 | import pathlib as non_alias
    -   |                   ^^^^^^^^^ F401
    +   |                   ^^^^^^^^^
      9 |
     10 | # Unused, marked as required.
        |
    -   = help: Remove unused import: `pathlib`
    +help: Remove unused import: `pathlib`
    

    For now, the primary difference is the movement of the filename, line number, and column information to a second line in the header. This new representation will allow us to make further additions to Ruff's diagnostics, such as adding sub-diagnostics and multiple annotations to the same snippet.

0.12.10

Preview features

  • [flake8-simplify] Implement fix for maxsplit without separator (SIM905) (#19851)
  • [flake8-use-pathlib] Add fixes for PTH102 and PTH103 (#19514)

Bug fixes

  • [isort] Handle multiple continuation lines after module docstring (I002) (#19818)
  • [pyupgrade] Avoid reporting __future__ features as unnecessary when they are used (UP010) (#19769)
  • [pyupgrade] Handle nested Optionals (UP045) (#19770)

Rule changes

  • [pycodestyle] Make E731 fix unsafe instead of display-only for class assignments (#19700)
  • [pyflakes] Add secondary annotation showing previous definition (F811) (#19900)

Documentation

0.12.11

Preview features

  • [airflow] Extend AIR311 and AIR312 rules (#20082)
  • [airflow] Replace wrong path airflow.io.storage with airflow.io.store (AIR311) (#20081)
  • [flake8-async] Implement blocking-http-call-httpx-in-async-function (ASYNC212) (#20091)
  • [flake8-logging-format] Add auto-fix for f-string logging calls (G004) (#19303)
  • [flake8-use-pathlib] Add autofix for PTH211 (#20009)
  • [flake8-use-pathlib] Make PTH100 fix unsafe because it can change behavior (#20100)

Bug fixes

  • [pyflakes, pylint] Fix false positives caused by __class__ cell handling (F841, PLE0117) (#20048)
  • [pyflakes] Fix allowed-unused-imports matching for top-level modules (F401) (#20115)
  • [ruff] Fix false positive for t-strings in default-factory-kwarg (RUF026) (#20032)
  • [ruff] Preserve relative whitespace in multi-line expressions (RUF033) (#19647)

Rule changes

  • [ruff] Handle empty t-strings in unnecessary-empty-iterable-within-deque-call (RUF037) (#20045)

Documentation

  • Fix incorrect D413 links in docstrings convention FAQ (#20089)
  • [flake8-use-pathlib] Update links to the table showing the correspondence between os and pathlib (#20103)

0.12.12

Preview features

  • Show fixes by default (#19919)
  • [airflow] Convert DatasetOrTimeSchedule(datasets=...) to AssetOrTimeSchedule(assets=...) (AIR311) (#20202)
  • [airflow] Improve the AIR002 error message (#20173)
  • [airflow] Move airflow.operators.postgres_operator.Mapping from AIR302 to AIR301 (#20172)
  • [flake8-async] Implement blocking-input rule (ASYNC250) (#20122)
  • [flake8-use-pathlib] Make PTH119 and PTH120 fixes unsafe because they can change behavior (#20118)
  • [pylint] Add U+061C to PLE2502 (#20106)
  • [ruff] Fix false negative for empty f-strings in deque calls (RUF037) (#20109)

Bug fixes

  • Less confidently mark f-strings as empty when inferring truthiness (#20152)
  • [fastapi] Fix false positive for paths with spaces around parameters (FAST003) (#20077)
  • [flake8-comprehensions] Skip C417 when lambda contains yield/yield from (#20201)
  • [perflint] Handle tuples in dictionary comprehensions (PERF403) (#19934)

Rule changes

  • [pycodestyle] Preserve return type annotation for ParamSpec (E731) (#20108)

Documentation