An extremely fast Python linter, written in Rust.
Linting the CPython codebase from scratch.
- ⚡️ 10-100x faster than existing linters
- 🐍 Installable via
pip
- 🤝 Python 3.11 compatibility
- 🛠️
pyproject.toml
support - 📦 Built-in caching, to avoid re-analyzing unchanged files
- 🔧 Autofix support, for automatic error correction (e.g., automatically remove unused imports)
- ⚖️ Near-parity with the built-in Flake8 rule set
- 🔌 Native re-implementations of dozens of Flake8 plugins, like
flake8-bugbear
- ⌨️ First-party editor integrations for VS Code and more
- 🌎 Monorepo-friendly, with hierarchical and cascading configuration
Ruff aims to be orders of magnitude faster than alternative tools while integrating more functionality behind a single, common interface.
Ruff can be used to replace Flake8 (plus a variety of plugins), isort
,
pydocstyle
, yesqa
,
eradicate
, pyupgrade
,
and autoflake
, all while executing tens or hundreds of
times faster than any individual tool.
Ruff goes beyond the responsibilities of a traditional linter, instead functioning as an advanced code transformation tool capable of upgrading type annotations, rewriting class definitions, sorting imports, and more.
Ruff is extremely actively developed and used in major open-source projects like:
- FastAPI
- Bokeh
- Zulip
- Pydantic
- Sphinx
- Hatch
- Jupyter
- Synapse
- Saleor
- Polars
- Ibis
- OpenBB
pyca/cryptography
Read the launch blog post.
Sebastián Ramírez, creator of FastAPI:
Ruff is so fast that sometimes I add an intentional bug in the code just to confirm it's actually running and checking the code.
Bryan Van de Ven, co-creator of Bokeh, original author of Conda:
Ruff is ~150-200x faster than flake8 on my machine, scanning the whole repo takes ~0.2s instead of ~20s. This is an enormous quality of life improvement for local dev. It's fast enough that I added it as an actual commit hook, which is terrific.
Tim Abbott, lead developer of Zulip:
This is just ridiculously fast...
ruff
is amazing.
- Installation and Usage
- Configuration
- Supported Rules
- Pyflakes (F)
- pycodestyle (E, W)
- mccabe (C90)
- isort (I)
- pydocstyle (D)
- pyupgrade (UP)
- pep8-naming (N)
- flake8-2020 (YTT)
- flake8-annotations (ANN)
- flake8-bandit (S)
- flake8-blind-except (BLE)
- flake8-boolean-trap (FBT)
- flake8-bugbear (B)
- flake8-builtins (A)
- flake8-comprehensions (C4)
- flake8-debugger (T10)
- flake8-errmsg (EM)
- flake8-implicit-str-concat (ISC)
- flake8-import-conventions (ICN)
- flake8-print (T20)
- flake8-pytest-style (PT)
- flake8-quotes (Q)
- flake8-return (RET)
- flake8-simplify (SIM)
- flake8-tidy-imports (TID)
- flake8-unused-arguments (ARG)
- flake8-datetimez (DTZ)
- eradicate (ERA)
- pandas-vet (PD)
- pygrep-hooks (PGH)
- Pylint (PLC, PLE, PLR, PLW)
- flake8-pie (PIE)
- Ruff-specific rules (RUF)
- Editor Integrations
- FAQ
- Development
- Releases
- Benchmarks
- Reference
- License
- Contributing
Ruff is available as ruff
on PyPI:
pip install ruff
For macOS Homebrew and Linuxbrew users, Ruff is also available as ruff
on Homebrew:
brew install ruff
For Conda users, Ruff is also available as ruff
on conda-forge
:
conda install -c conda-forge ruff
For Arch Linux users, Ruff is also available as ruff
on the official repositories:
pacman -S ruff
To run Ruff, try any of the following:
ruff path/to/code/to/check.py # Run Ruff over `check.py`
ruff path/to/code/ # Run Ruff over all files in `/path/to/code` (and any subdirectories)
ruff path/to/code/*.py # Run Ruff over all `.py` files in `/path/to/code`
You can run Ruff in --watch
mode to automatically re-run on-change:
ruff path/to/code/ --watch
Ruff also works with pre-commit:
- repo: https://github.com/charliermarsh/ruff-pre-commit
# Ruff version.
rev: 'v0.0.215'
hooks:
- id: ruff
# Respect `exclude` and `extend-exclude` settings.
args: ["--force-exclude"]
Ruff is configurable both via pyproject.toml
and the command line. For a full list of configurable
options, see the API reference.
If left unspecified, the default configuration is equivalent to:
[tool.ruff]
line-length = 88
# Enable Pyflakes `E` and `F` codes by default.
select = ["E", "F"]
ignore = []
# Exclude a variety of commonly ignored directories.
exclude = [
".bzr",
".direnv",
".eggs",
".git",
".hg",
".mypy_cache",
".nox",
".pants.d",
".ruff_cache",
".svn",
".tox",
".venv",
"__pypackages__",
"_build",
"buck-out",
"build",
"dist",
"node_modules",
"venv",
]
per-file-ignores = {}
# Allow unused variables when underscore-prefixed.
dummy-variable-rgx = "^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$"
# Assume Python 3.10.
target-version = "py310"
[tool.ruff.mccabe]
# Unlike Flake8, default to a complexity level of 10.
max-complexity = 10
As an example, the following would configure Ruff to: (1) avoid checking for line-length
violations (E501
); (2) never remove unused imports (F401
); and (3) ignore import-at-top-of-file
errors (E402
) in __init__.py
files:
[tool.ruff]
# Enable Pyflakes and pycodestyle rules.
select = ["E", "F"]
# Never enforce `E501` (line length violations).
ignore = ["E501"]
# Never try to fix `F401` (unused imports).
unfixable = ["F401"]
# Ignore `E402` (import violations) in all `__init__.py` files, and in `path/to/file.py`.
[tool.ruff.per-file-ignores]
"__init__.py" = ["E402"]
"path/to/file.py" = ["E402"]
Plugin configurations should be expressed as subsections, e.g.:
[tool.ruff]
# Add "Q" to the list of enabled codes.
select = ["E", "F", "Q"]
[tool.ruff.flake8-quotes]
docstring-quotes = "double"
Ruff mirrors Flake8's error code system, in which each error code consists of a one-to-three letter
prefix, followed by three digits (e.g., F401
). The prefix indicates that "source" of the error
code (e.g., F
for Pyflakes, E
for pycodestyle
, ANN
for flake8-annotations
). The set of
enabled errors is determined by the select
and ignore
options, which support both the full
error code (e.g., F401
) and the prefix (e.g., F
).
As a special-case, Ruff also supports the ALL
error code, which enables all error codes. Note that
some of the pydocstyle
error codes are conflicting (e.g., D203
and D211
) as they represent
alternative docstring formats. Enabling ALL
without further configuration may result in suboptimal
behavior, especially for the pydocstyle
plugin.
As an alternative to pyproject.toml
, Ruff will also respect a ruff.toml
file, which implements
an equivalent schema (though the [tool.ruff]
hierarchy can be omitted). For example, the
pyproject.toml
described above would be represented via the following ruff.toml
:
# Enable Pyflakes and pycodestyle rules.
select = ["E", "F"]
# Never enforce `E501` (line length violations).
ignore = ["E501"]
# Always autofix, but never try to fix `F401` (unused imports).
fix = true
unfixable = ["F401"]
# Ignore `E402` (import violations) in all `__init__.py` files, and in `path/to/file.py`.
[per-file-ignores]
"__init__.py" = ["E402"]
"path/to/file.py" = ["E402"]
For a full list of configurable options, see the API reference.
Some common configuration settings can be provided via the command-line:
ruff path/to/code/ --select F401 --select F403
See ruff --help
for more:
Ruff: An extremely fast Python linter.
Usage: ruff [OPTIONS] [FILES]...
Arguments:
[FILES]...
Options:
--config <CONFIG>
Path to the `pyproject.toml` or `ruff.toml` file to use for configuration
-v, --verbose
Enable verbose logging
-q, --quiet
Only log errors
-s, --silent
Disable all logging (but still exit with status code "1" upon detecting errors)
-e, --exit-zero
Exit with status code "0", even upon detecting errors
-w, --watch
Run in watch mode by re-running whenever files change
--fix
Attempt to automatically fix lint errors
--fix-only
Fix any fixable lint errors, but don't report on leftover violations. Implies `--fix`
--diff
Avoid writing any fixed files back; instead, output a diff for each changed file to stdout
-n, --no-cache
Disable cache reads
--isolated
Ignore all configuration files
--select <SELECT>
Comma-separated list of error codes to enable (or ALL, to enable all checks)
--extend-select <EXTEND_SELECT>
Like --select, but adds additional error codes on top of the selected ones
--ignore <IGNORE>
Comma-separated list of error codes to disable
--extend-ignore <EXTEND_IGNORE>
Like --ignore, but adds additional error codes on top of the ignored ones
--exclude <EXCLUDE>
List of paths, used to exclude files and/or directories from checks
--extend-exclude <EXTEND_EXCLUDE>
Like --exclude, but adds additional files and directories on top of the excluded ones
--fixable <FIXABLE>
List of error codes to treat as eligible for autofix. Only applicable when autofix itself is enabled (e.g., via `--fix`)
--unfixable <UNFIXABLE>
List of error codes to treat as ineligible for autofix. Only applicable when autofix itself is enabled (e.g., via `--fix`)
--per-file-ignores <PER_FILE_IGNORES>
List of mappings from file pattern to code to exclude
--format <FORMAT>
Output serialization format for error messages [env: RUFF_FORMAT=] [possible values: text, json, junit, grouped, github, gitlab]
--stdin-filename <STDIN_FILENAME>
The name of the file when passing it through stdin
--cache-dir <CACHE_DIR>
Path to the cache directory [env: RUFF_CACHE_DIR=]
--show-source
Show violations with source code
--respect-gitignore
Respect file exclusions via `.gitignore` and other standard ignore files
--force-exclude
Enforce exclusions, even for paths passed to Ruff directly on the command-line
--update-check
Enable or disable automatic update checks
--dummy-variable-rgx <DUMMY_VARIABLE_RGX>
Regular expression matching the name of dummy variables
--target-version <TARGET_VERSION>
The minimum Python version that should be supported
--line-length <LINE_LENGTH>
Set the line-length for length-associated checks and automatic formatting
--max-complexity <MAX_COMPLEXITY>
Maximum McCabe complexity allowed for a given function
--add-noqa
Enable automatic additions of `noqa` directives to failing lines
--clean
Clear any caches in the current directory or any subdirectories
--explain <EXPLAIN>
Explain a rule
--show-files
See the files Ruff will be run against with the current settings
--show-settings
See the settings Ruff will use to check a given Python file
-h, --help
Print help information
-V, --version
Print version information
Similar to ESLint,
Ruff supports hierarchical configuration, such that the "closest" pyproject.toml
file in the
directory hierarchy is used for every individual file, with all paths in the pyproject.toml
file
(e.g., exclude
globs, src
paths) being resolved relative to the directory containing the
pyproject.toml
file.
There are a few exceptions to these rules:
- In locating the "closest"
pyproject.toml
file for a given path, Ruff ignores anypyproject.toml
files that lack a[tool.ruff]
section. - If a configuration file is passed directly via
--config
, those settings are used for across files. Any relative paths in that configuration file (likeexclude
globs orsrc
paths) are resolved relative to the current working directory. - If no
pyproject.toml
file is found in the filesystem hierarchy, Ruff will fall back to using a default configuration. If a user-specific configuration file exists at${config_dir}/ruff/pyproject.toml
, that file will be used instead of the default configuration, with${config_dir}
being determined via thedirs
crate, and all relative paths being again resolved relative to the current working directory. - Any
pyproject.toml
-supported settings that are provided on the command-line (e.g., via--select
) will override the settings in every resolved configuration file.
Unlike ESLint,
Ruff does not merge settings across configuration files; instead, the "closest" configuration file
is used, and any parent configuration files are ignored. In lieu of this implicit cascade, Ruff
supports an extend
field, which allows you to inherit the settings from another
pyproject.toml
file, like so:
# Extend the `pyproject.toml` file in the parent directory.
extend = "../pyproject.toml"
# But use a different line length.
line-length = 100
All of the above rules apply equivalently to ruff.toml
files. If Ruff detects both a ruff.toml
and pyproject.toml
file, it will defer to the ruff.toml
.
When passed a path on the command-line, Ruff will automatically discover all Python files in that
path, taking into account the exclude
and extend-exclude
settings
in each directory's pyproject.toml
file.
By default, Ruff will also skip any files that are omitted via .ignore
, .gitignore
,
.git/info/exclude
, and global gitignore
files (see: respect-gitignore
).
Files that are passed to ruff
directly are always checked, regardless of the above criteria.
For example, ruff /path/to/excluded/file.py
will always check file.py
.
To omit a lint check entirely, add it to the "ignore" list via ignore
or
extend-ignore
, either on the command-line or in your pyproject.toml
file.
To ignore an error inline, Ruff uses a noqa
system similar to Flake8.
To ignore an individual error, add # noqa: {code}
to the end of the line, like so:
# Ignore F841.
x = 1 # noqa: F841
# Ignore E741 and F841.
i = 1 # noqa: E741, F841
# Ignore _all_ errors.
x = 1 # noqa
Note that, for multi-line strings, the noqa
directive should come at the end of the string, and
will apply to the entire string, like so:
"""Lorem ipsum dolor sit amet.
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
""" # noqa: E501
To ignore all errors across an entire file, Ruff supports Flake8's # flake8: noqa
directive (or,
equivalently, # ruff: noqa
). Adding either of those directives to any part of a file will disable
error reporting for the entire file.
For targeted exclusions across entire files (e.g., "Ignore all F841 violations in
/path/to/file.py
"), see the per-file-ignores
configuration setting.
Ruff respects isort
's "Action Comments"
(# isort: skip_file
, # isort: on
, # isort: off
, # isort: skip
, and # isort: split
), which
enable selectively enabling and disabling import sorting for blocks of code and other inline
configuration.
See the isort
documentation
for more.
Ruff supports several workflows to aid in noqa
management.
First, Ruff provides a special error code, RUF100
, to enforce that your noqa
directives are
"valid", in that the errors they say they ignore are actually being triggered on that line (and
thus suppressed). You can run ruff /path/to/file.py --extend-select RUF100
to flag unused noqa
directives.
Second, Ruff can automatically remove unused noqa
directives via its autofix functionality.
You can run ruff /path/to/file.py --extend-select RUF100 --fix
to automatically remove unused
noqa
directives.
Third, Ruff can automatically add noqa
directives to all failing lines. This is useful when
migrating a new codebase to Ruff. You can run ruff /path/to/file.py --add-noqa
to automatically
add noqa
directives to all failing lines, with the appropriate error codes.
Regardless of the rule's origin, Ruff re-implements every rule in Rust as a first-party feature.
By default, Ruff enables all E
and F
error codes, which correspond to those built-in to Flake8.
The 🛠 emoji indicates that a rule is automatically fixable by the --fix
command-line option.
For more, see Pyflakes on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
F401 | UnusedImport | ... imported but unused |
🛠 |
F402 | ImportShadowedByLoopVar | Import ... from line 1 shadowed by loop variable |
|
F403 | ImportStarUsed | from ... import * used; unable to detect undefined names |
|
F404 | LateFutureImport | from __future__ imports must occur at the beginning of the file |
|
F405 | ImportStarUsage | ... may be undefined, or defined from star imports: ... |
|
F406 | ImportStarNotPermitted | from ... import * only allowed at module level |
|
F407 | FutureFeatureNotDefined | Future feature ... is not defined |
|
F501 | PercentFormatInvalidFormat | '...' % ... has invalid format string: ... | |
F502 | PercentFormatExpectedMapping | '...' % ... expected mapping but got sequence | |
F503 | PercentFormatExpectedSequence | '...' % ... expected sequence but got mapping | |
F504 | PercentFormatExtraNamedArguments | '...' % ... has unused named argument(s): ... | 🛠 |
F505 | PercentFormatMissingArgument | '...' % ... is missing argument(s) for placeholder(s): ... | |
F506 | PercentFormatMixedPositionalAndNamed | '...' % ... has mixed positional and named placeholders | |
F507 | PercentFormatPositionalCountMismatch | '...' % ... has 4 placeholder(s) but 2 substitution(s) | |
F508 | PercentFormatStarRequiresSequence | '...' % ... * specifier requires sequence |
|
F509 | PercentFormatUnsupportedFormatCharacter | '...' % ... has unsupported format character 'c' | |
F521 | StringDotFormatInvalidFormat | '...'.format(...) has invalid format string: ... | |
F522 | StringDotFormatExtraNamedArguments | '...'.format(...) has unused named argument(s): ... | 🛠 |
F523 | StringDotFormatExtraPositionalArguments | '...'.format(...) has unused arguments at position(s): ... | |
F524 | StringDotFormatMissingArguments | '...'.format(...) is missing argument(s) for placeholder(s): ... | |
F525 | StringDotFormatMixingAutomatic | '...'.format(...) mixes automatic and manual numbering | |
F541 | FStringMissingPlaceholders | f-string without any placeholders | 🛠 |
F601 | MultiValueRepeatedKeyLiteral | Dictionary key literal ... repeated |
🛠 |
F602 | MultiValueRepeatedKeyVariable | Dictionary key ... repeated |
🛠 |
F621 | ExpressionsInStarAssignment | Too many expressions in star-unpacking assignment | |
F622 | TwoStarredExpressions | Two starred expressions in assignment | |
F631 | AssertTuple | Assert test is a non-empty tuple, which is always True |
|
F632 | IsLiteral | Use == to compare constant literals |
🛠 |
F633 | InvalidPrintSyntax | Use of >> is invalid with print function |
|
F634 | IfTuple | If test is a tuple, which is always True |
|
F701 | BreakOutsideLoop | break outside loop |
|
F702 | ContinueOutsideLoop | continue not properly in loop |
|
F704 | YieldOutsideFunction | yield statement outside of a function |
|
F706 | ReturnOutsideFunction | return statement outside of a function/method |
|
F707 | DefaultExceptNotLast | An except block as not the last exception handler |
|
F722 | ForwardAnnotationSyntaxError | Syntax error in forward annotation: ... |
|
F811 | RedefinedWhileUnused | Redefinition of unused ... from line 1 |
|
F821 | UndefinedName | Undefined name ... |
|
F822 | UndefinedExport | Undefined name ... in __all__ |
|
F823 | UndefinedLocal | Local variable ... referenced before assignment |
|
F841 | UnusedVariable | Local variable ... is assigned to but never used |
🛠 |
F842 | UnusedAnnotation | Local variable ... is annotated but never used |
|
F901 | RaiseNotImplemented | raise NotImplemented should be raise NotImplementedError |
🛠 |
For more, see pycodestyle on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
E401 | MultipleImportsOnOneLine | Multiple imports on one line | |
E402 | ModuleImportNotAtTopOfFile | Module level import not at top of file | |
E501 | LineTooLong | Line too long (89 > 88 characters) | |
E711 | NoneComparison | Comparison to None should be cond is None |
🛠 |
E712 | TrueFalseComparison | Comparison to True should be cond is True |
🛠 |
E713 | NotInTest | Test for membership should be not in |
🛠 |
E714 | NotIsTest | Test for object identity should be is not |
🛠 |
E721 | TypeComparison | Do not compare types, use isinstance() |
|
E722 | DoNotUseBareExcept | Do not use bare except |
|
E731 | DoNotAssignLambda | Do not assign a lambda expression, use a def |
🛠 |
E741 | AmbiguousVariableName | Ambiguous variable name: ... |
|
E742 | AmbiguousClassName | Ambiguous class name: ... |
|
E743 | AmbiguousFunctionName | Ambiguous function name: ... |
|
E902 | IOError | IOError: ... |
|
E999 | SyntaxError | SyntaxError: ... |
|
W292 | NoNewLineAtEndOfFile | No newline at end of file | 🛠 |
W605 | InvalidEscapeSequence | Invalid escape sequence: '\c' | 🛠 |
For more, see mccabe on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
C901 | FunctionIsTooComplex | ... is too complex (10) |
For more, see isort on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
I001 | UnsortedImports | Import block is un-sorted or un-formatted | 🛠 |
For more, see pydocstyle on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
D100 | PublicModule | Missing docstring in public module | |
D101 | PublicClass | Missing docstring in public class | |
D102 | PublicMethod | Missing docstring in public method | |
D103 | PublicFunction | Missing docstring in public function | |
D104 | PublicPackage | Missing docstring in public package | |
D105 | MagicMethod | Missing docstring in magic method | |
D106 | PublicNestedClass | Missing docstring in public nested class | |
D107 | PublicInit | Missing docstring in __init__ |
|
D200 | FitsOnOneLine | One-line docstring should fit on one line | |
D201 | NoBlankLineBeforeFunction | No blank lines allowed before function docstring (found 1) | 🛠 |
D202 | NoBlankLineAfterFunction | No blank lines allowed after function docstring (found 1) | 🛠 |
D203 | OneBlankLineBeforeClass | 1 blank line required before class docstring | 🛠 |
D204 | OneBlankLineAfterClass | 1 blank line required after class docstring | 🛠 |
D205 | BlankLineAfterSummary | 1 blank line required between summary line and description (found 2) | 🛠 |
D206 | IndentWithSpaces | Docstring should be indented with spaces, not tabs | |
D207 | NoUnderIndentation | Docstring is under-indented | 🛠 |
D208 | NoOverIndentation | Docstring is over-indented | 🛠 |
D209 | NewLineAfterLastParagraph | Multi-line docstring closing quotes should be on a separate line | 🛠 |
D210 | NoSurroundingWhitespace | No whitespaces allowed surrounding docstring text | 🛠 |
D211 | NoBlankLineBeforeClass | No blank lines allowed before class docstring | 🛠 |
D212 | MultiLineSummaryFirstLine | Multi-line docstring summary should start at the first line | |
D213 | MultiLineSummarySecondLine | Multi-line docstring summary should start at the second line | |
D214 | SectionNotOverIndented | Section is over-indented ("Returns") | 🛠 |
D215 | SectionUnderlineNotOverIndented | Section underline is over-indented ("Returns") | 🛠 |
D300 | UsesTripleQuotes | Use """triple double quotes""" | |
D301 | UsesRPrefixForBackslashedContent | Use r""" if any backslashes in a docstring | |
D400 | EndsInPeriod | First line should end with a period | 🛠 |
D402 | NoSignature | First line should not be the function's signature | |
D403 | FirstLineCapitalized | First word of the first line should be properly capitalized | |
D404 | NoThisPrefix | First word of the docstring should not be "This" | |
D405 | CapitalizeSectionName | Section name should be properly capitalized ("returns") | 🛠 |
D406 | NewLineAfterSectionName | Section name should end with a newline ("Returns") | 🛠 |
D407 | DashedUnderlineAfterSection | Missing dashed underline after section ("Returns") | 🛠 |
D408 | SectionUnderlineAfterName | Section underline should be in the line following the section's name ("Returns") | 🛠 |
D409 | SectionUnderlineMatchesSectionLength | Section underline should match the length of its name ("Returns") | 🛠 |
D410 | BlankLineAfterSection | Missing blank line after section ("Returns") | 🛠 |
D411 | BlankLineBeforeSection | Missing blank line before section ("Returns") | 🛠 |
D412 | NoBlankLinesBetweenHeaderAndContent | No blank lines allowed between a section header and its content ("Returns") | 🛠 |
D413 | BlankLineAfterLastSection | Missing blank line after last section ("Returns") | 🛠 |
D414 | NonEmptySection | Section has no content ("Returns") | |
D415 | EndsInPunctuation | First line should end with a period, question mark, or exclamation point | 🛠 |
D416 | SectionNameEndsInColon | Section name should end with a colon ("Returns") | 🛠 |
D417 | DocumentAllArguments | Missing argument descriptions in the docstring: x , y |
|
D418 | SkipDocstring | Function decorated with @overload shouldn't contain a docstring |
|
D419 | NonEmpty | Docstring is empty |
For more, see pyupgrade on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
UP001 | UselessMetaclassType | __metaclass__ = type is implied |
🛠 |
UP003 | TypeOfPrimitive | Use str instead of type(...) |
🛠 |
UP004 | UselessObjectInheritance | Class ... inherits from object |
🛠 |
UP005 | DeprecatedUnittestAlias | assertEquals is deprecated, use assertEqual |
🛠 |
UP006 | UsePEP585Annotation | Use list instead of List for type annotations |
🛠 |
UP007 | UsePEP604Annotation | Use X | Y for type annotations |
🛠 |
UP008 | SuperCallWithParameters | Use super() instead of super(__class__, self) |
🛠 |
UP009 | PEP3120UnnecessaryCodingComment | UTF-8 encoding declaration is unnecessary | 🛠 |
UP010 | UnnecessaryFutureImport | Unnecessary __future__ import ... for target Python version |
🛠 |
UP011 | UnnecessaryLRUCacheParams | Unnecessary parameters to functools.lru_cache |
🛠 |
UP012 | UnnecessaryEncodeUTF8 | Unnecessary call to encode as UTF-8 |
🛠 |
UP013 | ConvertTypedDictFunctionalToClass | Convert ... from TypedDict functional to class syntax |
🛠 |
UP014 | ConvertNamedTupleFunctionalToClass | Convert ... from NamedTuple functional to class syntax |
🛠 |
UP015 | RedundantOpenModes | Unnecessary open mode parameters | 🛠 |
UP016 | RemoveSixCompat | Unnecessary six compatibility usage |
🛠 |
UP017 | DatetimeTimezoneUTC | Use datetime.UTC alias |
🛠 |
UP018 | NativeLiterals | Unnecessary call to str |
🛠 |
UP019 | TypingTextStrAlias | typing.Text is deprecated, use str |
🛠 |
UP020 | OpenAlias | Use builtin open |
🛠 |
UP021 | ReplaceUniversalNewlines | universal_newlines is deprecated, use text |
🛠 |
UP022 | ReplaceStdoutStderr | Sending stdout and stderr to pipe is deprecated, use capture_output |
🛠 |
UP023 | RewriteCElementTree | cElementTree is deprecated, use ElementTree |
🛠 |
UP024 | OSErrorAlias | Replace aliased errors with OSError |
🛠 |
UP025 | RewriteUnicodeLiteral | Remove unicode literals from strings | 🛠 |
UP026 | RewriteMockImport | mock is deprecated, use unittest.mock |
🛠 |
UP027 | RewriteListComprehension | Replace unpacked list comprehension with a generator expression | 🛠 |
UP028 | RewriteYieldFrom | Replace yield over for loop with yield from |
🛠 |
UP029 | UnnecessaryBuiltinImport | Unnecessary builtin import: ... |
🛠 |
For more, see pep8-naming on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
N801 | InvalidClassName | Class name ... should use CapWords convention |
|
N802 | InvalidFunctionName | Function name ... should be lowercase |
|
N803 | InvalidArgumentName | Argument name ... should be lowercase |
|
N804 | InvalidFirstArgumentNameForClassMethod | First argument of a class method should be named cls |
|
N805 | InvalidFirstArgumentNameForMethod | First argument of a method should be named self |
|
N806 | NonLowercaseVariableInFunction | Variable ... in function should be lowercase |
|
N807 | DunderFunctionName | Function name should not start and end with __ |
|
N811 | ConstantImportedAsNonConstant | Constant ... imported as non-constant ... |
|
N812 | LowercaseImportedAsNonLowercase | Lowercase ... imported as non-lowercase ... |
|
N813 | CamelcaseImportedAsLowercase | Camelcase ... imported as lowercase ... |
|
N814 | CamelcaseImportedAsConstant | Camelcase ... imported as constant ... |
|
N815 | MixedCaseVariableInClassScope | Variable mixedCase in class scope should not be mixedCase |
|
N816 | MixedCaseVariableInGlobalScope | Variable mixedCase in global scope should not be mixedCase |
|
N817 | CamelcaseImportedAsAcronym | Camelcase ... imported as acronym ... |
|
N818 | ErrorSuffixOnExceptionName | Exception name ... should be named with an Error suffix |
For more, see flake8-2020 on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
YTT101 | SysVersionSlice3Referenced | sys.version[:3] referenced (python3.10), use sys.version_info |
|
YTT102 | SysVersion2Referenced | sys.version[2] referenced (python3.10), use sys.version_info |
|
YTT103 | SysVersionCmpStr3 | sys.version compared to string (python3.10), use sys.version_info |
|
YTT201 | SysVersionInfo0Eq3Referenced | sys.version_info[0] == 3 referenced (python4), use >= |
|
YTT202 | SixPY3Referenced | six.PY3 referenced (python4), use not six.PY2 |
|
YTT203 | SysVersionInfo1CmpInt | sys.version_info[1] compared to integer (python4), compare sys.version_info to tuple |
|
YTT204 | SysVersionInfoMinorCmpInt | sys.version_info.minor compared to integer (python4), compare sys.version_info to tuple |
|
YTT301 | SysVersion0Referenced | sys.version[0] referenced (python10), use sys.version_info |
|
YTT302 | SysVersionCmpStr10 | sys.version compared to string (python10), use sys.version_info |
|
YTT303 | SysVersionSlice1Referenced | sys.version[:1] referenced (python10), use sys.version_info |
For more, see flake8-annotations on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
ANN001 | MissingTypeFunctionArgument | Missing type annotation for function argument ... |
|
ANN002 | MissingTypeArgs | Missing type annotation for *... |
|
ANN003 | MissingTypeKwargs | Missing type annotation for **... |
|
ANN101 | MissingTypeSelf | Missing type annotation for ... in method |
|
ANN102 | MissingTypeCls | Missing type annotation for ... in classmethod |
|
ANN201 | MissingReturnTypePublicFunction | Missing return type annotation for public function ... |
|
ANN202 | MissingReturnTypePrivateFunction | Missing return type annotation for private function ... |
|
ANN204 | MissingReturnTypeSpecialMethod | Missing return type annotation for special method ... |
🛠 |
ANN205 | MissingReturnTypeStaticMethod | Missing return type annotation for staticmethod ... |
|
ANN206 | MissingReturnTypeClassMethod | Missing return type annotation for classmethod ... |
|
ANN401 | DynamicallyTypedExpression | Dynamically typed expressions (typing.Any) are disallowed in ... |
For more, see flake8-bandit on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
S101 | AssertUsed | Use of assert detected |
|
S102 | ExecUsed | Use of exec detected |
|
S103 | BadFilePermissions | os.chmod setting a permissive mask 0o777 on file or directory |
|
S104 | HardcodedBindAllInterfaces | Possible binding to all interfaces | |
S105 | HardcodedPasswordString | Possible hardcoded password: "..." | |
S106 | HardcodedPasswordFuncArg | Possible hardcoded password: "..." | |
S107 | HardcodedPasswordDefault | Possible hardcoded password: "..." | |
S108 | HardcodedTempFile | Probable insecure usage of temporary file or directory: "..." | |
S113 | RequestWithoutTimeout | Probable use of requests call without timeout | |
S324 | HashlibInsecureHashFunction | Probable use of insecure hash functions in hashlib : "..." |
|
S501 | RequestWithNoCertValidation | Probable use of ... call with verify=False disabling SSL certificate checks |
|
S506 | UnsafeYAMLLoad | Probable use of unsafe yaml.load . Allows instantiation of arbitrary objects. Consider yaml.safe_load . |
For more, see flake8-blind-except on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
BLE001 | BlindExcept | Do not catch blind exception: Exception |
For more, see flake8-boolean-trap on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
FBT001 | BooleanPositionalArgInFunctionDefinition | Boolean positional arg in function definition | |
FBT002 | BooleanDefaultValueInFunctionDefinition | Boolean default value in function definition | |
FBT003 | BooleanPositionalValueInFunctionCall | Boolean positional value in function call |
For more, see flake8-bugbear on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
B002 | UnaryPrefixIncrement | Python does not support the unary prefix increment | |
B003 | AssignmentToOsEnviron | Assigning to os.environ doesn't clear the environment |
|
B004 | UnreliableCallableCheck | Using hasattr(x, '__call__') to test if x is callable is unreliable. Use callable(x) for consistent results. |
|
B005 | StripWithMultiCharacters | Using .strip() with multi-character strings is misleading the reader |
|
B006 | MutableArgumentDefault | Do not use mutable data structures for argument defaults | |
B007 | UnusedLoopControlVariable | Loop control variable i not used within the loop body |
🛠 |
B008 | FunctionCallArgumentDefault | Do not perform function call in argument defaults | |
B009 | GetAttrWithConstant | Do not call getattr with a constant attribute value. It is not any safer than normal property access. |
🛠 |
B010 | SetAttrWithConstant | Do not call setattr with a constant attribute value. It is not any safer than normal property access. |
🛠 |
B011 | DoNotAssertFalse | Do not assert False (python -O removes these calls), raise AssertionError() |
🛠 |
B012 | JumpStatementInFinally | return/continue/break inside finally blocks cause exceptions to be silenced |
|
B013 | RedundantTupleInExceptionHandler | A length-one tuple literal is redundant. Write except ValueError instead of except (ValueError,) . |
🛠 |
B014 | DuplicateHandlerException | Exception handler with duplicate exception: ValueError |
🛠 |
B015 | UselessComparison | Pointless comparison. This comparison does nothing but waste CPU instructions. Either prepend assert or remove it. |
|
B016 | CannotRaiseLiteral | Cannot raise a literal. Did you intend to return it or raise an Exception? | |
B017 | NoAssertRaisesException | assertRaises(Exception) should be considered evil |
|
B018 | UselessExpression | Found useless expression. Either assign it to a variable or remove it. | |
B019 | CachedInstanceMethod | Use of functools.lru_cache or functools.cache on methods can lead to memory leaks |
|
B020 | LoopVariableOverridesIterator | Loop control variable ... overrides iterable it iterates |
|
B021 | FStringDocstring | f-string used as docstring. This will be interpreted by python as a joined string rather than a docstring. | |
B022 | UselessContextlibSuppress | No arguments passed to contextlib.suppress . No exceptions will be suppressed and therefore this context manager is redundant |
|
B023 | FunctionUsesLoopVariable | Function definition does not bind loop variable ... |
|
B024 | AbstractBaseClassWithoutAbstractMethod | ... is an abstract base class, but it has no abstract methods |
|
B025 | DuplicateTryBlockException | try-except block with duplicate exception Exception |
|
B026 | StarArgUnpackingAfterKeywordArg | Star-arg unpacking after a keyword argument is strongly discouraged | |
B027 | EmptyMethodWithoutAbstractDecorator | ... is an empty method in an abstract base class, but has no abstract decorator |
|
B904 | RaiseWithoutFromInsideExcept | Within an except clause, raise exceptions with raise ... from err or raise ... from None to distinguish them from errors in exception handling | |
B905 | ZipWithoutExplicitStrict | zip() without an explicit strict= parameter |
For more, see flake8-builtins on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
A001 | BuiltinVariableShadowing | Variable ... is shadowing a python builtin |
|
A002 | BuiltinArgumentShadowing | Argument ... is shadowing a python builtin |
|
A003 | BuiltinAttributeShadowing | Class attribute ... is shadowing a python builtin |
For more, see flake8-comprehensions on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
C400 | UnnecessaryGeneratorList | Unnecessary generator (rewrite as a list comprehension) |
🛠 |
C401 | UnnecessaryGeneratorSet | Unnecessary generator (rewrite as a set comprehension) |
🛠 |
C402 | UnnecessaryGeneratorDict | Unnecessary generator (rewrite as a dict comprehension) |
🛠 |
C403 | UnnecessaryListComprehensionSet | Unnecessary list comprehension (rewrite as a set comprehension) |
🛠 |
C404 | UnnecessaryListComprehensionDict | Unnecessary list comprehension (rewrite as a dict comprehension) |
🛠 |
C405 | UnnecessaryLiteralSet | Unnecessary (list|tuple) literal (rewrite as a set literal) |
🛠 |
C406 | UnnecessaryLiteralDict | Unnecessary (list|tuple) literal (rewrite as a dict literal) |
🛠 |
C408 | UnnecessaryCollectionCall | Unnecessary (dict|list|tuple) call (rewrite as a literal) |
🛠 |
C409 | UnnecessaryLiteralWithinTupleCall | Unnecessary (list|tuple) literal passed to tuple() (remove the outer call to tuple() ) |
🛠 |
C410 | UnnecessaryLiteralWithinListCall | Unnecessary (list|tuple) literal passed to list() (rewrite as a list literal) |
🛠 |
C411 | UnnecessaryListCall | Unnecessary list call (remove the outer call to list() ) |
🛠 |
C413 | UnnecessaryCallAroundSorted | Unnecessary (list|reversed) call around sorted() |
🛠 |
C414 | UnnecessaryDoubleCastOrProcess | Unnecessary (list|reversed|set|sorted|tuple) call within (list|set|sorted|tuple)() |
|
C415 | UnnecessarySubscriptReversal | Unnecessary subscript reversal of iterable within (reversed|set|sorted)() |
|
C416 | UnnecessaryComprehension | Unnecessary (list|set) comprehension (rewrite using (list|set)() ) |
🛠 |
C417 | UnnecessaryMap | Unnecessary map usage (rewrite using a (list|set|dict) comprehension) |
For more, see flake8-debugger on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
T100 | Debugger | Import for ... found |
For more, see flake8-errmsg on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
EM101 | RawStringInException | Exception must not use a string literal, assign to variable first | |
EM102 | FStringInException | Exception must not use an f-string literal, assign to variable first | |
EM103 | DotFormatInException | Exception must not use a .format() string directly, assign to variable first |
For more, see flake8-implicit-str-concat on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
ISC001 | SingleLineImplicitStringConcatenation | Implicitly concatenated string literals on one line | |
ISC002 | MultiLineImplicitStringConcatenation | Implicitly concatenated string literals over continuation line | |
ISC003 | ExplicitStringConcatenation | Explicitly concatenated string should be implicitly concatenated |
Code | Name | Message | Fix |
---|---|---|---|
ICN001 | ImportAliasIsNotConventional | ... should be imported as ... |
For more, see flake8-print on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
T201 | PrintFound | print found |
🛠 |
T203 | PPrintFound | pprint found |
🛠 |
For more, see flake8-pytest-style on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
PT001 | IncorrectFixtureParenthesesStyle | Use @pytest.fixture() over @pytest.fixture |
🛠 |
PT002 | FixturePositionalArgs | Configuration for fixture ... specified via positional args, use kwargs |
|
PT003 | ExtraneousScopeFunction | scope='function' is implied in @pytest.fixture() |
|
PT004 | MissingFixtureNameUnderscore | Fixture ... does not return anything, add leading underscore |
|
PT005 | IncorrectFixtureNameUnderscore | Fixture ... returns a value, remove leading underscore |
|
PT006 | ParametrizeNamesWrongType | Wrong name(s) type in @pytest.mark.parametrize , expected tuple |
🛠 |
PT007 | ParametrizeValuesWrongType | Wrong values type in @pytest.mark.parametrize expected list of tuple |
|
PT008 | PatchWithLambda | Use return_value= instead of patching with lambda |
|
PT009 | UnittestAssertion | Use a regular assert instead of unittest-style ... |
🛠 |
PT010 | RaisesWithoutException | set the expected exception in pytest.raises() |
|
PT011 | RaisesTooBroad | pytest.raises(...) is too broad, set the match parameter or use a more specific exception |
|
PT012 | RaisesWithMultipleStatements | pytest.raises() block should contain a single simple statement |
|
PT013 | IncorrectPytestImport | Found incorrect import of pytest, use simple import pytest instead |
|
PT015 | AssertAlwaysFalse | Assertion always fails, replace with pytest.fail() |
|
PT016 | FailWithoutMessage | No message passed to pytest.fail() |
|
PT017 | AssertInExcept | Found assertion on exception ... in except block, use pytest.raises() instead |
|
PT018 | CompositeAssertion | Assertion should be broken down into multiple parts | |
PT019 | FixtureParamWithoutValue | Fixture ... without value is injected as parameter, use @pytest.mark.usefixtures instead |
|
PT020 | DeprecatedYieldFixture | @pytest.yield_fixture is deprecated, use @pytest.fixture |
|
PT021 | FixtureFinalizerCallback | Use yield instead of request.addfinalizer |
|
PT022 | UselessYieldFixture | No teardown in fixture ... , use return instead of yield |
🛠 |
PT023 | IncorrectMarkParenthesesStyle | Use @pytest.mark.... over @pytest.mark....() |
🛠 |
PT024 | UnnecessaryAsyncioMarkOnFixture | pytest.mark.asyncio is unnecessary for fixtures |
|
PT025 | ErroneousUseFixturesOnFixture | pytest.mark.usefixtures has no effect on fixtures |
|
PT026 | UseFixturesWithoutParameters | Useless pytest.mark.usefixtures without parameters |
🛠 |
For more, see flake8-quotes on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
Q000 | BadQuotesInlineString | Single quotes found but double quotes preferred | |
Q001 | BadQuotesMultilineString | Single quote multiline found but double quotes preferred | |
Q002 | BadQuotesDocstring | Single quote docstring found but double quotes preferred | |
Q003 | AvoidQuoteEscape | Change outer quotes to avoid escaping inner quotes |
For more, see flake8-return on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
RET501 | UnnecessaryReturnNone | Do not explicitly return None in function if it is the only possible return value |
🛠 |
RET502 | ImplicitReturnValue | Do not implicitly return None in function able to return non-None value |
🛠 |
RET503 | ImplicitReturn | Missing explicit return at the end of function able to return non-None value |
🛠 |
RET504 | UnnecessaryAssign | Unnecessary variable assignment before return statement |
|
RET505 | SuperfluousElseReturn | Unnecessary else after return statement |
|
RET506 | SuperfluousElseRaise | Unnecessary else after raise statement |
|
RET507 | SuperfluousElseContinue | Unnecessary else after continue statement |
|
RET508 | SuperfluousElseBreak | Unnecessary else after break statement |
For more, see flake8-simplify on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
SIM101 | DuplicateIsinstanceCall | Multiple isinstance calls for ... , merge into a single call |
🛠 |
SIM102 | NestedIfStatements | Use a single if statement instead of nested if statements |
|
SIM103 | ReturnBoolConditionDirectly | Return the condition ... directly |
🛠 |
SIM105 | UseContextlibSuppress | Use contextlib.suppress(...) instead of try-except-pass |
|
SIM107 | ReturnInTryExceptFinally | Don't use return in try /except and finally |
|
SIM108 | UseTernaryOperator | Use ternary operator ... instead of if-else-block |
🛠 |
SIM109 | CompareWithTuple | Use value in (..., ...) instead of value == ... or value == ... |
🛠 |
SIM110 | ConvertLoopToAny | Use return any(x for x in y) instead of for loop |
🛠 |
SIM111 | ConvertLoopToAll | Use return all(x for x in y) instead of for loop |
🛠 |
SIM117 | MultipleWithStatements | Use a single with statement with multiple contexts instead of nested with statements |
|
SIM118 | KeyInDict | Use key in dict instead of key in dict.keys() |
🛠 |
SIM201 | NegateEqualOp | Use left != right instead of not left == right |
🛠 |
SIM202 | NegateNotEqualOp | Use left == right instead of not left != right |
🛠 |
SIM208 | DoubleNegation | Use expr instead of not (not expr) |
🛠 |
SIM210 | IfExprWithTrueFalse | Use bool(expr) instead of True if expr else False |
🛠 |
SIM211 | IfExprWithFalseTrue | Use not expr instead of False if expr else True |
🛠 |
SIM212 | IfExprWithTwistedArms | Use b if b else a instead of a if not b else b |
🛠 |
SIM220 | AAndNotA | Use False instead of ... and not ... |
🛠 |
SIM221 | AOrNotA | Use True instead of ... or not ... |
🛠 |
SIM222 | OrTrue | Use True instead of ... or True |
🛠 |
SIM223 | AndFalse | Use False instead of ... and False |
🛠 |
SIM300 | YodaConditions | Yoda conditions are discouraged, use left == right instead |
🛠 |
For more, see flake8-tidy-imports on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
TID251 | BannedApi | ... is banned: ... |
|
TID252 | BannedRelativeImport | Relative imports are banned |
For more, see flake8-unused-arguments on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
ARG001 | UnusedFunctionArgument | Unused function argument: ... |
|
ARG002 | UnusedMethodArgument | Unused method argument: ... |
|
ARG003 | UnusedClassMethodArgument | Unused class method argument: ... |
|
ARG004 | UnusedStaticMethodArgument | Unused static method argument: ... |
|
ARG005 | UnusedLambdaArgument | Unused lambda argument: ... |
For more, see flake8-datetimez on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
DTZ001 | CallDatetimeWithoutTzinfo | The use of datetime.datetime() without tzinfo argument is not allowed |
|
DTZ002 | CallDatetimeToday | The use of datetime.datetime.today() is not allowed |
|
DTZ003 | CallDatetimeUtcnow | The use of datetime.datetime.utcnow() is not allowed |
|
DTZ004 | CallDatetimeUtcfromtimestamp | The use of datetime.datetime.utcfromtimestamp() is not allowed |
|
DTZ005 | CallDatetimeNowWithoutTzinfo | The use of datetime.datetime.now() without tz argument is not allowed |
|
DTZ006 | CallDatetimeFromtimestamp | The use of datetime.datetime.fromtimestamp() without tz argument is not allowed |
|
DTZ007 | CallDatetimeStrptimeWithoutZone | The use of datetime.datetime.strptime() without %z must be followed by .replace(tzinfo=) |
|
DTZ011 | CallDateToday | The use of datetime.date.today() is not allowed. |
|
DTZ012 | CallDateFromtimestamp | The use of datetime.date.fromtimestamp() is not allowed |
For more, see eradicate on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
ERA001 | CommentedOutCode | Found commented-out code | 🛠 |
For more, see pandas-vet on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
PD002 | UseOfInplaceArgument | inplace=True should be avoided; it has inconsistent behavior |
|
PD003 | UseOfDotIsNull | .isna is preferred to .isnull ; functionality is equivalent |
|
PD004 | UseOfDotNotNull | .notna is preferred to .notnull ; functionality is equivalent |
|
PD007 | UseOfDotIx | .ix is deprecated; use more explicit .loc or .iloc |
|
PD008 | UseOfDotAt | Use .loc instead of .at . If speed is important, use numpy. |
|
PD009 | UseOfDotIat | Use .iloc instead of .iat . If speed is important, use numpy. |
|
PD010 | UseOfDotPivotOrUnstack | .pivot_table is preferred to .pivot or .unstack ; provides same functionality |
|
PD011 | UseOfDotValues | Use .to_numpy() instead of .values |
|
PD012 | UseOfDotReadTable | .read_csv is preferred to .read_table ; provides same functionality |
|
PD013 | UseOfDotStack | .melt is preferred to .stack ; provides same functionality |
|
PD015 | UseOfPdMerge | Use .merge method instead of pd.merge function. They have equivalent functionality. |
|
PD901 | DfIsABadVariableName | df is a bad variable name. Be kinder to your future self. |
For more, see pygrep-hooks on GitHub.
Code | Name | Message | Fix |
---|---|---|---|
PGH001 | NoEval | No builtin eval() allowed |
|
PGH002 | DeprecatedLogWarn | warn is deprecated in favor of warning |
|
PGH003 | BlanketTypeIgnore | Use specific error codes when ignoring type issues | |
PGH004 | BlanketNOQA | Use specific error codes when using noqa |
For more, see Pylint on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
PLC0414 | UselessImportAlias | Import alias does not rename original package | 🛠 |
PLC2201 | MisplacedComparisonConstant | Comparison should be ... | 🛠 |
PLC3002 | UnnecessaryDirectLambdaCall | Lambda expression called directly. Execute the expression inline instead. | |
PLE0117 | NonlocalWithoutBinding | Nonlocal name ... found without binding |
|
PLE0118 | UsedPriorGlobalDeclaration | Name ... is used prior to global declaration on line 1 |
|
PLE1142 | AwaitOutsideAsync | await should be used within an async function |
|
PLR0206 | PropertyWithParameters | Cannot have defined parameters for properties | |
PLR0402 | ConsiderUsingFromImport | Use from ... import ... in lieu of alias |
|
PLR1701 | ConsiderMergingIsinstance | Merge these isinstance calls: isinstance(..., (...)) |
|
PLR1722 | UseSysExit | Use sys.exit() instead of exit |
🛠 |
PLW0120 | UselessElseOnLoop | Else clause on loop without a break statement, remove the else and de-indent all the code inside it | |
PLW0602 | GlobalVariableNotAssigned | Using global for ... but no assignment is done |
For more, see flake8-pie on PyPI.
Code | Name | Message | Fix |
---|---|---|---|
PIE790 | NoUnnecessaryPass | Unnecessary pass statement |
🛠 |
PIE794 | DupeClassFieldDefinitions | Class field ... is defined multiple times |
🛠 |
PIE807 | PreferListBuiltin | Prefer list() over useless lambda |
🛠 |
Code | Name | Message | Fix |
---|---|---|---|
RUF001 | AmbiguousUnicodeCharacterString | String contains ambiguous unicode character '𝐁' (did you mean 'B'?) | 🛠 |
RUF002 | AmbiguousUnicodeCharacterDocstring | Docstring contains ambiguous unicode character '𝐁' (did you mean 'B'?) | 🛠 |
RUF003 | AmbiguousUnicodeCharacterComment | Comment contains ambiguous unicode character '𝐁' (did you mean 'B'?) | 🛠 |
RUF004 | KeywordArgumentBeforeStarArgument | Keyword argument ... must come after starred arguments |
|
RUF100 | UnusedNOQA | Unused blanket noqa directive |
🛠 |
Download the Ruff VS Code extension, which supports autofix actions, import sorting, and more.
Ruff supports the Language Server Protocol
via the ruff-lsp
Python package, available on
PyPI.
ruff-lsp
enables Ruff to be used with any editor that
supports the Language Server Protocol, including Neovim,
Sublime Text, Emacs, and more.
For example, to use ruff-lsp
with Neovim, install ruff-lsp
from PyPI along with
nvim-lspconfig
. Then, add something like the following
to your init.lua
:
-- See: https://github.com/neovim/nvim-lspconfig/tree/54eb2a070a4f389b1be0f98070f81d23e2b1a715#suggested-configuration
local opts = { noremap=true, silent=true }
vim.keymap.set('n', '<space>e', vim.diagnostic.open_float, opts)
vim.keymap.set('n', '[d', vim.diagnostic.goto_prev, opts)
vim.keymap.set('n', ']d', vim.diagnostic.goto_next, opts)
vim.keymap.set('n', '<space>q', vim.diagnostic.setloclist, opts)
-- Use an on_attach function to only map the following keys
-- after the language server attaches to the current buffer
local on_attach = function(client, bufnr)
-- Enable completion triggered by <c-x><c-o>
vim.api.nvim_buf_set_option(bufnr, 'omnifunc', 'v:lua.vim.lsp.omnifunc')
-- Mappings.
-- See `:help vim.lsp.*` for documentation on any of the below functions
local bufopts = { noremap=true, silent=true, buffer=bufnr }
vim.keymap.set('n', 'gD', vim.lsp.buf.declaration, bufopts)
vim.keymap.set('n', 'gd', vim.lsp.buf.definition, bufopts)
vim.keymap.set('n', 'K', vim.lsp.buf.hover, bufopts)
vim.keymap.set('n', 'gi', vim.lsp.buf.implementation, bufopts)
vim.keymap.set('n', '<C-k>', vim.lsp.buf.signature_help, bufopts)
vim.keymap.set('n', '<space>wa', vim.lsp.buf.add_workspace_folder, bufopts)
vim.keymap.set('n', '<space>wr', vim.lsp.buf.remove_workspace_folder, bufopts)
vim.keymap.set('n', '<space>wl', function()
print(vim.inspect(vim.lsp.buf.list_workspace_folders()))
end, bufopts)
vim.keymap.set('n', '<space>D', vim.lsp.buf.type_definition, bufopts)
vim.keymap.set('n', '<space>rn', vim.lsp.buf.rename, bufopts)
vim.keymap.set('n', '<space>ca', vim.lsp.buf.code_action, bufopts)
vim.keymap.set('n', 'gr', vim.lsp.buf.references, bufopts)
vim.keymap.set('n', '<space>f', function() vim.lsp.buf.format { async = true } end, bufopts)
end
-- Configure `ruff-lsp`.
local configs = require 'lspconfig.configs'
if not configs.ruff_lsp then
configs.ruff_lsp = {
default_config = {
cmd = { 'ruff-lsp' },
filetypes = { 'python' },
root_dir = require('lspconfig').util.find_git_ancestor,
init_options = {
settings = {
args = {}
}
}
}
}
end
require('lspconfig').ruff_lsp.setup {
on_attach = on_attach,
}
Upon successful installation, you should see Ruff's diagnostics surfaced directly in your editor:
To use ruff-lsp
with other editors, including Sublime Text and Helix, see the ruff-lsp
documentation.
Ruff is also available as the python-lsp-ruff
plugin for python-lsp-server
, both of which are
installable from PyPI:
pip install python-lsp-server python-lsp-ruff
The LSP server can then be used with any editor that supports the Language Server Protocol.
For example, to use python-lsp-ruff
with Neovim, add something like the following to your
init.lua
:
require'lspconfig'.pylsp.setup {
settings = {
pylsp = {
plugins = {
ruff = {
enabled = true
},
pycodestyle = {
enabled = false
},
pyflakes = {
enabled = false
},
mccabe = {
enabled = false
}
}
}
},
}
Ruff can be integrated into any editor that supports the Language Server Protocol via ruff-lsp
(see: Language Server Protocol), including Vim and Neovim.
It's recommended that you use ruff-lsp
, the
officially supported LSP server for Ruff.
However, Ruff is also available as part of the coc-pyright
extension for coc.nvim
.
Ruff can also be integrated via efm
in just a few lines.
tools:
python-ruff: &python-ruff
lint-command: 'ruff --config ~/myconfigs/linters/ruff.toml --quiet ${INPUT}'
lint-stdin: true
lint-formats:
- '%f:%l:%c: %m'
format-command: 'ruff --stdin-filename ${INPUT} --config ~/myconfigs/linters/ruff.toml --fix --exit-zero --quiet -'
format-stdin: true
For neovim users using null-ls
, Ruff is already integrated.
local null_ls = require("null-ls")
local methods = require("null-ls.methods")
local helpers = require("null-ls.helpers")
local function ruff_fix()
return helpers.make_builtin({
name = "ruff",
meta = {
url = "https://github.com/charliermarsh/ruff/",
description = "An extremely fast Python linter, written in Rust.",
},
method = methods.internal.FORMATTING,
filetypes = { "python" },
generator_opts = {
command = "ruff",
args = { "--fix", "-e", "-n", "--stdin-filename", "$FILENAME", "-" },
to_stdin = true
},
factory = helpers.formatter_factory
})
end
null_ls.setup({
sources = {
ruff_fix(),
null_ls.builtins.diagnostics.ruff,
}
})
Ruff can be installed as an External Tool in PyCharm. Open the Preferences pane, then navigate to "Tools", then "External Tools". From there, add a new tool with the following configuration:
Ruff should then appear as a runnable action:
Ruff is also available as the Ruff plugin on the IntelliJ Marketplace (maintained by @koxudaxi).
GitHub Actions has everything you need to run Ruff out-of-the-box:
name: CI
on: push
jobs:
build:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v3
- name: Install Python
uses: actions/setup-python@v4
with:
python-version: "3.11"
- name: Install dependencies
run: |
python -m pip install --upgrade pip
pip install ruff
# Include `--format=github` to enable automatic inline annotations.
- name: Run Ruff
run: ruff --format=github .
Yes. Ruff is compatible with Black out-of-the-box, as long as
the line-length
setting is consistent between the two.
As a project, Ruff is designed to be used alongside Black and, as such, will defer implementing stylistic lint rules that are obviated by autoformatting.
(Coming from Flake8? Try flake8-to-ruff
to
automatically convert your existing configuration.)
Ruff can be used as a drop-in replacement for Flake8 when used (1) without or with a small number of plugins, (2) alongside Black, and (3) on Python 3 code.
Under those conditions, Ruff implements every rule in Flake8.
Ruff also re-implements some of the most popular Flake8 plugins and related code quality tools natively, including:
autoflake
(#1647)eradicate
flake8-2020
flake8-annotations
flake8-bandit
(#1646)flake8-blind-except
flake8-boolean-trap
flake8-bugbear
flake8-builtins
flake8-comprehensions
flake8-datetimez
flake8-debugger
flake8-docstrings
flake8-eradicate
flake8-errmsg
flake8-implicit-str-concat
flake8-import-conventions
flake8-pie
(#1543)flake8-print
flake8-quotes
flake8-return
flake8-simplify
(#998)flake8-super
flake8-tidy-imports
isort
mccabe
pep8-naming
pydocstyle
pygrep-hooks
(#980)pyupgrade
(#827)yesqa
Note that, in some cases, Ruff uses different error code prefixes than would be found in the
originating Flake8 plugins. For example, Ruff uses TID252
to represent the I252
rule from
flake8-tidy-imports
. This helps minimize conflicts across plugins and allows any individual plugin
to be toggled on or off with a single (e.g.) --select TID
, as opposed to --select I2
(to avoid
conflicts with the isort
rules, like I001
).
Beyond the rule set, Ruff suffers from the following limitations vis-à-vis Flake8:
- Ruff does not yet support structural pattern matching.
- Flake8 has a plugin architecture and supports writing custom lint rules. (Instead, popular Flake8 plugins are re-implemented in Rust as part of Ruff itself.)
There are a few other minor incompatibilities between Ruff and the originating Flake8 plugins:
- Ruff doesn't implement the "opinionated" lint rules from
flake8-bugbear
. - Depending on your project structure, Ruff and
isort
can differ in their detection of first-party code. (This is often solved by modifying thesrc
property, e.g., tosrc = ["src"]
, if your code is nested in asrc
directory.)
At time of writing, Pylint implements 409 total rules, while Ruff implements 224, of which at least 60 overlap with the Pylint rule set. Subjectively, Pylint tends to implement more rules based on type inference (e.g., validating the number of arguments in a function call).
Like Flake8, Pylint supports plugins (called "checkers"), while Ruff implements all checks natively.
Unlike Pylint, Ruff is capable of automatically fixing its own lint errors.
Pylint parity is being tracked in #689.
Today, Ruff can be used to replace Flake8 when used with any of the following plugins:
flake8-2020
flake8-annotations
flake8-bandit
(#1646)flake8-blind-except
flake8-boolean-trap
flake8-bugbear
flake8-builtins
flake8-comprehensions
flake8-datetimez
flake8-debugger
flake8-docstrings
flake8-eradicate
flake8-errmsg
flake8-implicit-str-concat
flake8-import-conventions
flake8-pie
(#1543)flake8-print
flake8-quotes
flake8-return
flake8-simplify
(#998)flake8-super
flake8-tidy-imports
mccabe
pep8-naming
pydocstyle
Ruff can also replace isort
,
yesqa
, eradicate
,
pygrep-hooks
(#980), and a subset of the rules
implemented in pyupgrade
(#827).
If you're looking to use Ruff, but rely on an unsupported Flake8 plugin, feel free to file an Issue.
Nope! Ruff is available as ruff
on PyPI:
pip install ruff
Ruff ships with wheels for all major platforms, which enables pip
to install Ruff without relying
on Rust at all.
Ruff does not yet support third-party plugins, though a plugin system is within-scope for the project. See #283 for more.
How does Ruff's import sorting compare to isort
?
Ruff's import sorting is intended to be nearly equivalent to isort
when used profile = "black"
.
(There are some minor differences in how Ruff and isort break ties between similar imports.)
Like isort
, Ruff's import sorting is compatible with Black.
Ruff is less configurable than isort
, but supports the known-first-party
, known-third-party
,
extra-standard-library
, and src
settings, like so:
[tool.ruff]
select = [
# Pyflakes
"F",
# Pycodestyle
"E",
"W",
# isort
"I001"
]
src = ["src", "tests"]
[tool.ruff.isort]
known-first-party = ["my_module1", "my_module2"]
Ruff is integrated into nbQA, a tool for running linters and code formatters over Jupyter Notebooks.
After installing ruff
and nbqa
, you can run Ruff over a notebook like so:
> nbqa ruff Untitled.ipynb
Untitled.ipynb:cell_1:2:5: F841 Local variable `x` is assigned to but never used
Untitled.ipynb:cell_2:1:1: E402 Module level import not at top of file
Untitled.ipynb:cell_2:1:8: F401 `os` imported but unused
Found 3 error(s).
1 potentially fixable with the --fix option.
Yes! To enable specific docstring convention, add the following to your pyproject.toml
:
[tool.ruff.pydocstyle]
convention = "google" # Accepts: "google", "numpy", or "pep257".
For example, if you're coming from flake8-docstrings
, and your originating configuration uses
--docstring-convention=numpy
, you'd instead set convention = "numpy"
in your pyproject.toml
,
as above.
Alongside convention
, you'll want to explicitly enable the D
error code class, like so:
[tool.ruff]
select = [
"D",
]
[tool.ruff.pydocstyle]
convention = "google"
Setting a convention
force-disables any rules that are incompatible with that convention, no
matter how they're provided, which avoids accidental incompatibilities and simplifies configuration.
Run ruff /path/to/code.py --show-settings
to view the resolved settings for a given file.
Ruff is written in Rust (1.65.0). You'll need to install the Rust toolchain for development.
Assuming you have cargo
installed, you can run:
cargo run resources/test/fixtures
For development, we use nightly Rust:
cargo +nightly fmt
cargo +nightly clippy --fix --workspace --all-targets --all-features -- -W clippy::pedantic
cargo +nightly test --all
Ruff is distributed on PyPI, and published via maturin
.
See: .github/workflows/release.yaml
.
First, clone CPython. It's a large and diverse Python codebase, which makes it a good target for benchmarking.
git clone --branch 3.10 https://github.com/python/cpython.git resources/test/cpython
Add this pyproject.toml
to the CPython directory:
[tool.ruff]
line-length = 88
extend-exclude = [
"Lib/lib2to3/tests/data/bom.py",
"Lib/lib2to3/tests/data/crlf.py",
"Lib/lib2to3/tests/data/different_encoding.py",
"Lib/lib2to3/tests/data/false_encoding.py",
"Lib/lib2to3/tests/data/py2_test_grammar.py",
"Lib/test/bad_coding2.py",
"Lib/test/badsyntax_3131.py",
"Lib/test/badsyntax_pep3120.py",
"Lib/test/encoded_modules/module_iso_8859_1.py",
"Lib/test/encoded_modules/module_koi8_r.py",
"Lib/test/test_fstring.py",
"Lib/test/test_grammar.py",
"Lib/test/test_importlib/test_util.py",
"Lib/test/test_named_expressions.py",
"Lib/test/test_patma.py",
"Lib/test/test_source_encoding.py",
"Tools/c-analyzer/c_parser/parser/_delim.py",
"Tools/i18n/pygettext.py",
"Tools/test2to3/maintest.py",
"Tools/test2to3/setup.py",
"Tools/test2to3/test/test_foo.py",
"Tools/test2to3/test2to3/hello.py",
]
Next, to benchmark the release build:
cargo build --release
hyperfine --ignore-failure --warmup 10 --runs 100 \
"./target/release/ruff ./resources/test/cpython/ --no-cache" \
"./target/release/ruff ./resources/test/cpython/"
Benchmark 1: ./target/release/ruff ./resources/test/cpython/ --no-cache
Time (mean ± σ): 297.4 ms ± 4.9 ms [User: 2460.0 ms, System: 67.2 ms]
Range (min … max): 287.7 ms … 312.1 ms 100 runs
Warning: Ignoring non-zero exit code.
Benchmark 2: ./target/release/ruff ./resources/test/cpython/
Time (mean ± σ): 79.6 ms ± 7.3 ms [User: 59.7 ms, System: 356.1 ms]
Range (min … max): 62.4 ms … 111.2 ms 100 runs
Warning: Ignoring non-zero exit code.
To benchmark against the ecosystem's existing tools:
hyperfine --ignore-failure --warmup 5 \
"./target/release/ruff ./resources/test/cpython/ --no-cache" \
"pylint --recursive=y resources/test/cpython/" \
"pyflakes resources/test/cpython" \
"autoflake --recursive --expand-star-imports --remove-all-unused-imports --remove-unused-variables --remove-duplicate-keys resources/test/cpython" \
"pycodestyle resources/test/cpython" \
"flake8 resources/test/cpython" \
"python -m scripts.run_flake8 resources/test/cpython"
In order, these evaluate:
- Ruff
- Pylint
- Pyflakes
- autoflake
- pycodestyle
- Flake8
- Flake8, with a hack to enable multiprocessing on macOS
(You can poetry install
from ./scripts
to create a working environment for the above.)
Benchmark 1: ./target/release/ruff ./resources/test/cpython/ --no-cache
Time (mean ± σ): 297.9 ms ± 7.0 ms [User: 2436.6 ms, System: 65.9 ms]
Range (min … max): 289.9 ms … 314.6 ms 10 runs
Warning: Ignoring non-zero exit code.
Benchmark 2: pylint --recursive=y resources/test/cpython/
Time (mean ± σ): 37.634 s ± 0.225 s [User: 36.728 s, System: 0.853 s]
Range (min … max): 37.201 s … 38.106 s 10 runs
Warning: Ignoring non-zero exit code.
Benchmark 3: pyflakes resources/test/cpython
Time (mean ± σ): 40.950 s ± 0.449 s [User: 40.688 s, System: 0.229 s]
Range (min … max): 40.348 s … 41.671 s 10 runs
Warning: Ignoring non-zero exit code.
Benchmark 4: autoflake --recursive --expand-star-imports --remove-all-unused-imports --remove-unused-variables --remove-duplicate-keys resources/test/cpython
Time (mean ± σ): 11.562 s ± 0.160 s [User: 107.022 s, System: 1.143 s]
Range (min … max): 11.417 s … 11.917 s 10 runs
Benchmark 5: pycodestyle resources/test/cpython
Time (mean ± σ): 67.428 s ± 0.985 s [User: 67.199 s, System: 0.203 s]
Range (min … max): 65.313 s … 68.496 s 10 runs
Warning: Ignoring non-zero exit code.
Benchmark 6: flake8 resources/test/cpython
Time (mean ± σ): 116.099 s ± 1.178 s [User: 115.217 s, System: 0.845 s]
Range (min … max): 114.180 s … 117.724 s 10 runs
Warning: Ignoring non-zero exit code.
Benchmark 7: python -m scripts.run_flake8 resources/test/cpython
Time (mean ± σ): 20.477 s ± 0.349 s [User: 142.372 s, System: 1.504 s]
Range (min … max): 20.107 s … 21.183 s 10 runs
Summary
'./target/release/ruff ./resources/test/cpython/ --no-cache' ran
38.81 ± 1.05 times faster than 'autoflake --recursive --expand-star-imports --remove-all-unused-imports --remove-unused-variables --remove-duplicate-keys resources/test/cpython'
68.74 ± 1.99 times faster than 'python -m scripts.run_flake8 resources/test/cpython'
126.33 ± 3.05 times faster than 'pylint --recursive=y resources/test/cpython/'
137.46 ± 3.55 times faster than 'pyflakes resources/test/cpython'
226.35 ± 6.23 times faster than 'pycodestyle resources/test/cpython'
389.73 ± 9.92 times faster than 'flake8 resources/test/cpython'
A list of allowed "confusable" Unicode characters to ignore when
enforcing RUF001
, RUF002
, and RUF003
.
Default value: []
Type: Vec<char>
Example usage:
[tool.ruff]
# Allow minus-sign (U+2212), greek-small-letter-rho (U+03C1), and the asterisk-operator (U+2217),
# which could be confused for "-", "p", and "*", respectively.
allowed-confusables = ["−", "ρ", "∗"]
A path to the cache directory.
By default, Ruff stores cache results in a .ruff_cache
directory in
the current project root.
However, Ruff will also respect the RUFF_CACHE_DIR
environment
variable, which takes precedence over that default.
This setting will override even the RUFF_CACHE_DIR
environment
variable, if set.
Default value: .ruff_cache
Type: PathBuf
Example usage:
[tool.ruff]
cache-dir = "~/.cache/ruff"
A regular expression used to identify "dummy" variables, or those which
should be ignored when evaluating (e.g.) unused-variable checks. The
default expression matches _
, __
, and _var
, but not _var_
.
Default value: "^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$"
Type: Regex
Example usage:
[tool.ruff]
# Only ignore variables named "_".
dummy-variable-rgx = "^_$"
A list of file patterns to exclude from linting.
Exclusions are based on globs, and can be either:
- Single-path patterns, like
.mypy_cache
(to exclude any directory named.mypy_cache
in the tree),foo.py
(to exclude any file namedfoo.py
), orfoo_*.py
(to exclude any file matchingfoo_*.py
). - Relative patterns, like
directory/foo.py
(to exclude that specific file) ordirectory/*.py
(to exclude any Python files indirectory
). Note that these paths are relative to the project root (e.g., the directory containing yourpyproject.toml
).
Note that you'll typically want to use
extend-exclude
to modify the excluded paths.
Default value: [".bzr", ".direnv", ".eggs", ".git", ".hg", ".mypy_cache", ".nox", ".pants.d", ".ruff_cache", ".svn", ".tox", ".venv", "__pypackages__", "_build", "buck-out", "build", "dist", "node_modules", "venv"]
Type: Vec<FilePattern>
Example usage:
[tool.ruff]
exclude = [".venv"]
A path to a local pyproject.toml
file to merge into this
configuration. User home directory and environment variables will be
expanded.
To resolve the current pyproject.toml
file, Ruff will first resolve
this base configuration file, then merge in any properties defined
in the current configuration file.
Default value: None
Type: Path
Example usage:
[tool.ruff]
# Extend the `pyproject.toml` file in the parent directory.
extend = "../pyproject.toml"
# But use a different line length.
line-length = 100
A list of file patterns to omit from linting, in addition to those
specified by exclude
.
Default value: []
Type: Vec<FilePattern>
Example usage:
[tool.ruff]
# In addition to the standard set of exclusions, omit all tests, plus a specific file.
extend-exclude = ["tests", "src/bad.py"]
A list of check code prefixes to ignore, in addition to those specified
by ignore
.
Default value: []
Type: Vec<CheckCodePrefix>
Example usage:
[tool.ruff]
# Skip unused variable checks (`F841`).
extend-ignore = ["F841"]
A list of check code prefixes to enable, in addition to those specified
by select
.
Default value: []
Type: Vec<CheckCodePrefix>
Example usage:
[tool.ruff]
# On top of the default `select` (`E`, `F`), enable flake8-bugbear (`B`) and flake8-quotes (`Q`).
extend-select = ["B", "Q"]
A list of check codes that are unsupported by Ruff, but should be
preserved when (e.g.) validating # noqa
directives. Useful for
retaining # noqa
directives that cover plugins not yet implemented
in Ruff.
Default value: []
Type: Vec<String>
Example usage:
[tool.ruff]
# Avoiding flagging (and removing) `V101` from any `# noqa`
# directives, despite Ruff's lack of support for `vulture`.
external = ["V101"]
Enable autofix behavior by-default when running ruff
(overridden
by the --fix
and --no-fix
command-line flags).
Default value: false
Type: bool
Example usage:
[tool.ruff]
fix = true
Like fix
, but disables reporting on leftover violation. Implies fix
.
Default value: false
Type: bool
Example usage:
[tool.ruff]
fix-only = true
A list of check code prefixes to consider autofix-able.
Default value: ["A", "ANN", "ARG", "B", "BLE", "C", "D", "E", "ERA", "F", "FBT", "I", "ICN", "N", "PGH", "PLC", "PLE", "PLR", "PLW", "Q", "RET", "RUF", "S", "T", "TID", "UP", "W", "YTT"]
Type: Vec<CheckCodePrefix>
Example usage:
[tool.ruff]
# Only allow autofix behavior for `E` and `F` checks.
fixable = ["E", "F"]
Whether to enforce exclude
and extend-exclude
patterns, even for
paths that are passed to Ruff explicitly. Typically, Ruff will lint
any paths passed in directly, even if they would typically be
excluded. Setting force-exclude = true
will cause Ruff to
respect these exclusions unequivocally.
This is useful for pre-commit
, which explicitly passes all
changed files to the ruff-pre-commit
plugin, regardless of whether they're marked as excluded by Ruff's own
settings.
Default value: false
Type: bool
Example usage:
[tool.ruff]
force-exclude = true
The style in which violation messages should be formatted: "text"
(default), "grouped"
(group messages by file), "json"
(machine-readable), "junit"
(machine-readable XML), "github"
(GitHub Actions annotations) or "gitlab"
(GitLab CI code quality report).
Default value: "text"
Type: SerializationType
Example usage:
[tool.ruff]
# Group violations by containing file.
format = "grouped"
A list of check code prefixes to ignore. Prefixes can specify exact
checks (like F841
), entire categories (like F
), or anything in
between.
When breaking ties between enabled and disabled checks (via select
and
ignore
, respectively), more specific prefixes override less
specific prefixes.
Default value: []
Type: Vec<CheckCodePrefix>
Example usage:
[tool.ruff]
# Skip unused variable checks (`F841`).
ignore = ["F841"]
Avoid automatically removing unused imports in __init__.py
files. Such
imports will still be +flagged, but with a dedicated message
suggesting that the import is either added to the module' +__all__
symbol, or re-exported with a redundant alias (e.g., import os as os
).
Default value: false
Type: bool
Example usage:
[tool.ruff]
ignore-init-module-imports = true
The line length to use when enforcing long-lines violations (like
E501
).
Default value: 88
Type: usize
Example usage:
[tool.ruff]
# Allow lines to be as long as 120 characters.
line-length = 120
A list of mappings from file pattern to check code prefixes to exclude, when considering any matching files.
Default value: {}
Type: HashMap<String, Vec<CheckCodePrefix>>
Example usage:
[tool.ruff]
# Ignore `E402` (import violations) in all `__init__.py` files, and in `path/to/file.py`.
[tool.ruff.per-file-ignores]
"__init__.py" = ["E402"]
"path/to/file.py" = ["E402"]
Require a specific version of Ruff to be running (useful for unifying
results across many environments, e.g., with a pyproject.toml
file).
Default value: None
Type: String
Example usage:
[tool.ruff]
required-version = "0.0.193"
Whether to automatically exclude files that are ignored by .ignore
,
.gitignore
, .git/info/exclude
, and global gitignore
files.
Enabled by default.
Default value: true
Type: bool
Example usage:
[tool.ruff]
respect_gitignore = false
A list of check code prefixes to enable. Prefixes can specify exact
checks (like F841
), entire categories (like F
), or anything in
between.
When breaking ties between enabled and disabled checks (via select
and
ignore
, respectively), more specific prefixes override less
specific prefixes.
Default value: ["E", "F"]
Type: Vec<CheckCodePrefix>
Example usage:
[tool.ruff]
# On top of the defaults (`E`, `F`), enable flake8-bugbear (`B`) and flake8-quotes (`Q`).
select = ["E", "F", "B", "Q"]
Whether to show source code snippets when reporting lint error
violations (overridden by the --show-source
command-line flag).
Default value: false
Type: bool
Example usage:
[tool.ruff]
# By default, always show source code snippets.
show-source = true
The source code paths to consider, e.g., when resolving first- vs. third-party imports.
As an example: given a Python package structure like:
my_package/
pyproject.toml
src/
my_package/
__init__.py
foo.py
bar.py
The src
directory should be included in source
(e.g., source = ["src"]
), such that when resolving imports, my_package.foo
is
considered a first-party import.
This field supports globs. For example, if you have a series of Python
packages in a python_modules
directory, src = ["python_modules/*"]
would expand to incorporate all of the
packages in that directory. User home directory and environment
variables will also be expanded.
Default value: ["."]
Type: Vec<PathBuf>
Example usage:
[tool.ruff]
# Allow imports relative to the "src" and "test" directories.
src = ["src", "test"]
The Python version to target, e.g., when considering automatic code upgrades, like rewriting type annotations. Note that the target version will not be inferred from the current Python version, and instead must be specified explicitly (as seen below).
Default value: "py310"
Type: PythonVersion
Example usage:
[tool.ruff]
# Always generate Python 3.7-compatible code.
target-version = "py37"
A list of task tags to recognize (e.g., "TODO", "FIXME", "XXX").
Comments starting with these tags will be ignored by commented-out code
detection (ERA
), and skipped by line-length checks (E501
) if
ignore-overlong-task-comments
is set to true
.
Default value: ["TODO", "FIXME", "XXX"]
Type: Vec<String>
Example usage:
[tool.ruff]
task-tags = ["HACK"]
A list of check code prefixes to consider un-autofix-able.
Default value: []
Type: Vec<CheckCodePrefix>
Example usage:
[tool.ruff]
# Disable autofix for unused imports (`F401`).
unfixable = ["F401"]
Enable or disable automatic update checks (overridden by the
--update-check
and --no-update-check
command-line flags).
Default value: true
Type: bool
Example usage:
[tool.ruff]
update-check = false
Whether to suppress ANN401
for dynamically typed *args
and
**kwargs
arguments.
Default value: false
Type: bool
Example usage:
[tool.ruff.flake8-annotations]
allow-star-arg-any = true
Whether to allow the omission of a return type hint for __init__
if at
least one argument is annotated.
Default value: false
Type: bool
Example usage:
[tool.ruff.flake8-annotations]
mypy-init-return = true
Whether to suppress ANN000
-level errors for arguments matching the
"dummy" variable regex (like _
).
Default value: false
Type: bool
Example usage:
[tool.ruff.flake8-annotations]
suppress-dummy-args = true
Whether to suppress ANN200
-level errors for functions that meet either
of the following criteria:
- Contain no
return
statement. - Explicit
return
statement(s) all returnNone
(explicitly or implicitly).
Default value: false
Type: bool
Example usage:
[tool.ruff.flake8-annotations]
suppress-none-returning = true
A list of directories to consider temporary.
Default value: ["/tmp", "/var/tmp", "/dev/shm"]
Type: Vec<String>
Example usage:
[tool.ruff.flake8-bandit]
hardcoded-tmp-directory = ["/foo/bar"]
A list of directories to consider temporary, in addition to those
specified by hardcoded-tmp-directory
.
Default value: []
Type: Vec<String>
Example usage:
[tool.ruff.flake8-bandit]
extend-hardcoded-tmp-directory = ["/foo/bar"]
Additional callable functions to consider "immutable" when evaluating,
e.g., no-mutable-default-argument
checks (B006
).
Default value: []
Type: Vec<String>
Example usage:
[tool.ruff.flake8-bugbear]
# Allow default arguments like, e.g., `data: List[str] = fastapi.Query(None)`.
extend-immutable-calls = ["fastapi.Depends", "fastapi.Query"]
Maximum string length for string literals in exception messages.
Default value: 0
Type: usize
Example usage:
[tool.ruff.flake8-errmsg]
max-string-length = 20
The conventional aliases for imports. These aliases can be extended by
the extend_aliases
option.
Default value: {"altair": "alt", "matplotlib.pyplot": "plt", "numpy": "np", "pandas": "pd", "seaborn": "sns"}
Type: FxHashMap<String, String>
Example usage:
[tool.ruff.flake8-import-conventions]
[tool.ruff.flake8-import-conventions.aliases]
# Declare the default aliases.
altair = "alt"
"matplotlib.pyplot" = "plt"
numpy = "np"
pandas = "pd"
seaborn = "sns"
A mapping of modules to their conventional import aliases. These aliases
will be added to the aliases
mapping.
Default value: {}
Type: FxHashMap<String, String>
Example usage:
[tool.ruff.flake8-import-conventions]
[tool.ruff.flake8-import-conventions.extend-aliases]
# Declare a custom alias for the `matplotlib` module.
"dask.dataframe" = "dd"
Boolean flag specifying whether @pytest.fixture()
without parameters
should have parentheses. If the option is set to true
(the
default), @pytest.fixture()
is valid and @pytest.fixture
is an
error. If set to false
, @pytest.fixture
is valid and
@pytest.fixture()
is an error.
Default value: true
Type: bool
Example usage:
[tool.ruff.flake8-pytest-style]
fixture-parentheses = true
Boolean flag specifying whether @pytest.mark.foo()
without parameters
should have parentheses. If the option is set to true
(the
default), @pytest.mark.foo()
is valid and @pytest.mark.foo
is an
error. If set to false
, @pytest.fixture
is valid and
@pytest.mark.foo()
is an error.
Default value: true
Type: bool
Example usage:
[tool.ruff.flake8-pytest-style]
mark-parentheses = true
Expected type for multiple argument names in @pytest.mark.parametrize
.
The following values are supported:
csv
— a comma-separated list, e.g.@pytest.mark.parametrize('name1,name2', ...)
tuple
(default) — e.g.@pytest.mark.parametrize(('name1', 'name2'), ...)
list
— e.g.@pytest.mark.parametrize(['name1', 'name2'], ...)
Default value: tuple
Type: ParametrizeNameType
Example usage:
[tool.ruff.flake8-pytest-style]
parametrize-names-type = "list"
Expected type for each row of values in @pytest.mark.parametrize
in
case of multiple parameters. The following values are supported:
tuple
(default) — e.g.@pytest.mark.parametrize(('name1', 'name2'), [(1, 2), (3, 4)])
list
— e.g.@pytest.mark.parametrize(('name1', 'name2'), [[1, 2], [3, 4]])
Default value: tuple
Type: ParametrizeValuesRowType
Example usage:
[tool.ruff.flake8-pytest-style]
parametrize-values-row-type = "list"
Expected type for the list of values rows in @pytest.mark.parametrize
.
The following values are supported:
tuple
— e.g.@pytest.mark.parametrize('name', (1, 2, 3))
list
(default) — e.g.@pytest.mark.parametrize('name', [1, 2, 3])
Default value: list
Type: ParametrizeValuesType
Example usage:
[tool.ruff.flake8-pytest-style]
parametrize-values-type = "tuple"
List of additional exception names that require a match= parameter in a
pytest.raises()
call. This extends the default list of exceptions
that require a match= parameter.
This option is useful if you want to extend the default list of
exceptions that require a match= parameter without having to specify
the entire list.
Note that this option does not remove any exceptions from the default
list.
Default value: []
Type: Vec<String>
Example usage:
[tool.ruff.flake8-pytest-style]
raises-extend-require-match-for = ["requests.RequestException"]
List of exception names that require a match= parameter in a
pytest.raises()
call.
Default value: ["BaseException", "Exception", "ValueError", "OSError", "IOError", "EnvironmentError", "socket.error"]
Type: Vec<String>
Example usage:
[tool.ruff.flake8-pytest-style]
raises-require-match-for = ["requests.RequestException"]
Whether to avoid using single quotes if a string contains single quotes, or vice-versa with double quotes, as per PEP8. This minimizes the need to escape quotation marks within strings.
Default value: true
Type: bool
Example usage:
[tool.ruff.flake8-quotes]
# Don't bother trying to avoid escapes.
avoid-escape = false
Quote style to prefer for docstrings (either "single" ('
) or "double"
("
)).
Default value: "double"
Type: Quote
Example usage:
[tool.ruff.flake8-quotes]
docstring-quotes = "single"
Quote style to prefer for inline strings (either "single" ('
) or
"double" ("
)).
Default value: "double"
Type: Quote
Example usage:
[tool.ruff.flake8-quotes]
inline-quotes = "single"
Quote style to prefer for multiline strings (either "single" ('
) or
"double" ("
)).
Default value: "double"
Type: Quote
Example usage:
[tool.ruff.flake8-quotes]
multiline-quotes = "single"
Whether to ban all relative imports ("all"
), or only those imports
that extend into the parent module or beyond ("parents"
).
Default value: "parents"
Type: Strictness
Example usage:
[tool.ruff.flake8-tidy-imports]
# Disallow all relative imports.
ban-relative-imports = "all"
Specific modules or module members that may not be imported or accessed.
Note that this check is only meant to flag accidental uses,
and can be circumvented via eval
or importlib
.
Default value: {}
Type: HashMap<String, BannedApi>
Example usage:
[tool.ruff.flake8-tidy-imports]
[tool.ruff.flake8-tidy-imports.banned-api]
"cgi".msg = "The cgi module is deprecated, see https://peps.python.org/pep-0594/#cgi."
"typing.TypedDict".msg = "Use typing_extensions.TypedDict instead."
Whether to allow unused variadic arguments, like *args
and **kwargs
.
Default value: false
Type: bool
Example usage:
[tool.ruff.flake8-unused-arguments]
ignore-variadic-names = true
Combines as imports on the same line. See isort's combine-as-imports
option.
Default value: false
Type: bool
Example usage:
[tool.ruff.isort]
combine-as-imports = true
A list of modules to consider standard-library, in addition to those known to Ruff in advance.
Default value: []
Type: Vec<String>
Example usage:
[tool.ruff.isort]
extra-standard-library = ["path"]
Forces all from imports to appear on their own line.
Default value: false
Type: bool
Example usage:
[tool.ruff.isort]
force-single-line = true
Force import from
statements with multiple members and at least one
alias (e.g., import A as B
) to wrap such that every line contains
exactly one member. For example, this formatting would be retained,
rather than condensing to a single line:
from .utils import (
test_directory as test_directory,
test_id as test_id
)
Note that this setting is only effective when combined with
combine-as-imports = true
. When combine-as-imports
isn't
enabled, every aliased import from
will be given its own line, in
which case, wrapping is not necessary.
Default value: false
Type: bool
Example usage:
[tool.ruff.isort]
force-wrap-aliases = true
combine-as-imports = true
A list of modules to consider first-party, regardless of whether they can be identified as such via introspection of the local filesystem.
Default value: []
Type: Vec<String>
Example usage:
[tool.ruff.isort]
known-first-party = ["src"]
A list of modules to consider third-party, regardless of whether they can be identified as such via introspection of the local filesystem.
Default value: []
Type: Vec<String>
Example usage:
[tool.ruff.isort]
known-third-party = ["src"]
Order imports by type, which is determined by case, in addition to alphabetically.
Default value: true
Type: bool
Example usage:
[tool.ruff.isort]
order-by-type = true
One or more modules to exclude from the single line rule.
Default value: []
Type: Vec<String>
Example usage:
[tool.ruff.isort]
single-line-exclusions = ["os", "json"]
If a comma is placed after the last member in a multi-line import, then the imports will never be folded into one line.
See isort's split-on-trailing-comma
option.
Default value: true
Type: bool
Example usage:
[tool.ruff.isort]
split-on-trailing-comma = false
The maximum McCabe complexity to allow before triggering C901
errors.
Default value: 10
Type: usize
Example usage:
[tool.ruff.mccabe]
# Flag errors (`C901`) whenever the complexity level exceeds 5.
max-complexity = 5
A list of decorators that, when applied to a method, indicate that the
method should be treated as a class method. For example, Ruff will
expect that any method decorated by a decorator in this list takes a
cls
argument as its first argument.
Default value: ["classmethod"]
Type: Vec<String>
Example usage:
[tool.ruff.pep8-naming]
# Allow Pydantic's `@validator` decorator to trigger class method treatment.
classmethod-decorators = ["classmethod", "pydantic.validator"]
A list of names to ignore when considering pep8-naming
violations.
Default value: ["setUp", "tearDown", "setUpClass", "tearDownClass", "setUpModule", "tearDownModule", "asyncSetUp", "asyncTearDown", "setUpTestData", "failureException", "longMessage", "maxDiff"]
Type: Vec<String>
Example usage:
[tool.ruff.pep8-naming]
ignore-names = ["callMethod"]
A list of decorators that, when applied to a method, indicate that the
method should be treated as a static method. For example, Ruff will
expect that any method decorated by a decorator in this list has no
self
or cls
argument.
Default value: ["staticmethod"]
Type: Vec<String>
Example usage:
[tool.ruff.pep8-naming]
# Allow a shorthand alias, `@stcmthd`, to trigger static method treatment.
staticmethod-decorators = ["staticmethod", "stcmthd"]
Whether or not line-length checks (E501
) should be triggered for
comments starting with task-tags
(by default: ["TODO", "FIXME",
and "XXX"]).
Default value: false
Type: bool
Example usage:
[tool.ruff.pycodestyle]
ignore-overlong-task-comments = true
Whether to use Google-style or NumPy-style conventions or the PEP257 defaults when analyzing docstring sections.
Default value: None
Type: Convention
Example usage:
[tool.ruff.pydocstyle]
# Use Google-style docstrings.
convention = "google"
Whether to avoid PEP 585 (List[int]
-> list[int]
) and PEP 604
(Optional[str]
-> str | None
) rewrites even if a file imports from __future__ import annotations
. Note that this setting is only
applicable when the target Python version is below 3.9 and 3.10
respectively.
Default value: false
Type: bool
Example usage:
[tool.ruff.pyupgrade]
# Preserve types, even if a file imports `from __future__ import annotations`.
keep-runtime-typing = true
MIT
Contributions are welcome and hugely appreciated. To get started, check out the contributing guidelines.