Rules

Ruff supports over 900 lint rules, many of which are inspired by popular tools like Flake8, isort, pyupgrade, and others. Regardless of the rule's origin, Ruff re-implements every rule in Rust as a first-party feature.

By default, Ruff enables Flake8's F rules, along with a subset of the E rules, omitting any stylistic rules that overlap with the use of a formatter, like ruff format or Black.

If you're just getting started with Ruff, the default rule set is a great place to start: it catches a wide variety of common errors (like unused imports) with zero configuration.

In preview, Ruff enables an expanded set of default rules that includes rules from the B, UP, and RUF categories, as well as many more. If you give the new defaults a try, feel free to leave feedback in the GitHub discussion, where you can also find the new rule set listed in full.

Legend

    🧪     The rule is unstable and is in "preview".
    ⚠️     The rule has been deprecated and will be removed in a future release.
    ❌     The rule has been removed only the documentation is available.
    🛠️     The rule is automatically fixable by the --fix command-line option.

All rules not marked as preview, deprecated or removed are stable.

Airflow (AIR)

For more, see Airflow on PyPI.

Code	Name	Message	Fix/Status
AIR001	airflow-variable-name-task-id-mismatch	Task variable name should match the task_id: "{task_id}"	Rule has been stable since v0.0.271
AIR002	airflow-dag-no-schedule-argument	DAG or @dag should have an explicit schedule argument	Rule has been stable since 0.13.0
AIR003	airflow-variable-get-outside-task	Variable.get() outside of a task	🧪Rule has been in preview since 0.15.6
AIR004	airflow-task-branch-as-short-circuit	@task.branch can be replaced with @task.short_circuit	🧪Rule has been in preview since 0.15.12
AIR201	airflow-xcom-pull-in-template-string	Use the .output attribute on the task object for "{task_id}" instead of xcom_pull in a template string	🧪Rule has been in preview since 0.15.11🛠️Automatic fix available
AIR301	airflow3-removal	{deprecated} is removed in Airflow 3.0	Rule has been stable since 0.13.0🛠️Automatic fix available
AIR302	airflow3-moved-to-provider	{deprecated} is moved into {provider} provider in Airflow 3.0;	Rule has been stable since 0.13.0🛠️Automatic fix available
AIR303	airflow3-incompatible-function-signature	{function_name} signature is changed in Airflow 3.0	🧪Rule has been in preview since 0.14.11
AIR304	airflow3-dag-dynamic-value	{function_name}() produces a value that changes at runtime; using it in a Dag or task argument causes infinite Dag version creation	🧪Rule has been in preview since 0.15.6
AIR311	airflow3-suggested-update	{deprecated} is removed in Airflow 3.0; It still works in Airflow 3.0 but is expected to be removed in a future version.	Rule has been stable since 0.13.0🛠️Automatic fix available
AIR312	airflow3-suggested-to-move-to-provider	{deprecated} is deprecated and moved into {provider} provider in Airflow 3.0; It still works in Airflow 3.0 but is expected to be removed in a future version.	Rule has been stable since 0.13.0🛠️Automatic fix available
AIR321	airflow31-moved	{deprecated} is moved in Airflow 3.1	🧪Rule has been in preview since 0.15.1🛠️Automatic fix available

eradicate (ERA)

For more, see eradicate on PyPI.

Code	Name	Message	Fix/Status
ERA001	commented-out-code	Found commented-out code	Rule has been stable since v0.0.145

FastAPI (FAST)

For more, see FastAPI on PyPI.

Code	Name	Message	Fix/Status
FAST001	fast-api-redundant-response-model	FastAPI route with redundant response_model argument	Rule has been stable since 0.8.0🛠️Automatic fix available
FAST002	fast-api-non-annotated-dependency	FastAPI dependency without Annotated	Rule has been stable since 0.8.0🛠️Automatic fix available
FAST003	fast-api-unused-path-parameter	Parameter {arg_name} appears in route path, but not in {function_name} signature	Rule has been stable since 0.10.0🛠️Automatic fix available

flake8-2020 (YTT)

For more, see flake8-2020 on PyPI.

Code	Name	Message	Fix/Status
YTT101	sys-version-slice3	sys.version[:3] referenced (python3.10), use sys.version_info	Rule has been stable since v0.0.113
YTT102	sys-version2	sys.version[2] referenced (python3.10), use sys.version_info	Rule has been stable since v0.0.113
YTT103	sys-version-cmp-str3	sys.version compared to string (python3.10), use sys.version_info	Rule has been stable since v0.0.113
YTT201	sys-version-info0-eq3	sys.version_info[0] == 3 referenced (python4), use >=	Rule has been stable since v0.0.113
YTT202	six-py3	six.PY3 referenced (python4), use not six.PY2	Rule has been stable since v0.0.113
YTT203	sys-version-info1-cmp-int	sys.version_info[1] compared to integer (python4), compare sys.version_info to tuple	Rule has been stable since v0.0.113
YTT204	sys-version-info-minor-cmp-int	sys.version_info.minor compared to integer (python4), compare sys.version_info to tuple	Rule has been stable since v0.0.113
YTT301	sys-version0	sys.version[0] referenced (python10), use sys.version_info	Rule has been stable since v0.0.113
YTT302	sys-version-cmp-str10	sys.version compared to string (python10), use sys.version_info	Rule has been stable since v0.0.113
YTT303	sys-version-slice1	sys.version[:1] referenced (python10), use sys.version_info	Rule has been stable since v0.0.113

flake8-annotations (ANN)

For more, see flake8-annotations on PyPI.

For related settings, see flake8-annotations.

Code	Name	Message	Fix/Status
ANN001	missing-type-function-argument	Missing type annotation for function argument {name}	Rule has been stable since v0.0.105
ANN002	missing-type-args	Missing type annotation for *{name}	Rule has been stable since v0.0.105
ANN003	missing-type-kwargs	Missing type annotation for **{name}	Rule has been stable since v0.0.105
ANN101	missing-type-self	Missing type annotation for {name} in method	❌Rule was removed in 0.8.0
ANN102	missing-type-cls	Missing type annotation for {name} in classmethod	❌Rule was removed in 0.8.0
ANN201	missing-return-type-undocumented-public-function	Missing return type annotation for public function {name}	Rule has been stable since v0.0.105🛠️Automatic fix available
ANN202	missing-return-type-private-function	Missing return type annotation for private function {name}	Rule has been stable since v0.0.105🛠️Automatic fix available
ANN204	missing-return-type-special-method	Missing return type annotation for special method {name}	Rule has been stable since v0.0.105🛠️Automatic fix available
ANN205	missing-return-type-static-method	Missing return type annotation for staticmethod {name}	Rule has been stable since v0.0.105🛠️Automatic fix available
ANN206	missing-return-type-class-method	Missing return type annotation for classmethod {name}	Rule has been stable since v0.0.105🛠️Automatic fix available
ANN401	any-type	Dynamically typed expressions (typing.Any) are disallowed in {name}	Rule has been stable since v0.0.108

flake8-async (ASYNC)

For more, see flake8-async on PyPI.

Code	Name	Message	Fix/Status
ASYNC100	cancel-scope-no-checkpoint	A with {method_name}(...): context does not contain any await statements. This makes it pointless, as the timeout can only be triggered by a checkpoint.	Rule has been stable since v0.0.269
ASYNC105	trio-sync-call	Call to {method_name} is not immediately awaited	Rule has been stable since 0.5.0🛠️Automatic fix available
ASYNC109	async-function-with-timeout	Async function definition with a timeout parameter	Rule has been stable since 0.5.0
ASYNC110	async-busy-wait	Use {module}.Event instead of awaiting {module}.sleep in a while loop	Rule has been stable since 0.5.0
ASYNC115	async-zero-sleep	Use {module}.lowlevel.checkpoint() instead of {module}.sleep(0)	Rule has been stable since 0.5.0🛠️Automatic fix available
ASYNC116	long-sleep-not-forever	{module}.sleep() with >24 hour interval should usually be {module}.sleep_forever()	Rule has been stable since 0.13.0🛠️Automatic fix available
ASYNC210	blocking-http-call-in-async-function	Async functions should not call blocking HTTP methods	Rule has been stable since 0.5.0
ASYNC212	blocking-http-call-httpx-in-async-function	Blocking httpx method {name}.{call}() in async context, use httpx.AsyncClient	Rule has been stable since 0.15.0
ASYNC220	create-subprocess-in-async-function	Async functions should not create subprocesses with blocking methods	Rule has been stable since 0.5.0
ASYNC221	run-process-in-async-function	Async functions should not run processes with blocking methods	Rule has been stable since 0.5.0
ASYNC222	wait-for-process-in-async-function	Async functions should not wait on processes with blocking methods	Rule has been stable since 0.5.0
ASYNC230	blocking-open-call-in-async-function	Async functions should not open files with blocking methods like open	Rule has been stable since 0.5.0
ASYNC240	blocking-path-method-in-async-function	Async functions should not use {path_library} methods, use trio.Path or anyio.path	Rule has been stable since 0.15.0
ASYNC250	blocking-input-in-async-function	Blocking call to input() in async context	Rule has been stable since 0.15.0
ASYNC251	blocking-sleep-in-async-function	Async functions should not call time.sleep	Rule has been stable since 0.5.0

flake8-bandit (S)

For more, see flake8-bandit on PyPI.

For related settings, see flake8-bandit.

Code	Name	Message	Fix/Status
S101	assert	Use of assert detected	Rule has been stable since v0.0.116
S102	exec-builtin	Use of exec detected	Rule has been stable since v0.0.116
S103	bad-file-permissions	os.chmod setting a permissive mask {mask:#o} on file or directory	Rule has been stable since v0.0.211
S104	hardcoded-bind-all-interfaces	Possible binding to all interfaces	Rule has been stable since v0.0.116
S105	hardcoded-password-string	Possible hardcoded password assigned to: "{}"	Rule has been stable since v0.0.116
S106	hardcoded-password-func-arg	Possible hardcoded password assigned to argument: "{}"	Rule has been stable since v0.0.116
S107	hardcoded-password-default	Possible hardcoded password assigned to function default: "{}"	Rule has been stable since v0.0.116
S108	hardcoded-temp-file	Probable insecure usage of temporary file or directory: "{}"	Rule has been stable since v0.0.211
S110	try-except-pass	try-except-pass detected, consider logging the exception	Rule has been stable since v0.0.237
S112	try-except-continue	try-except-continue detected, consider logging the exception	Rule has been stable since v0.0.245
S113	request-without-timeout	Probable use of {module} call without timeout	Rule has been stable since v0.0.213
S201	flask-debug-true	Use of debug=True in Flask app detected	Rule has been stable since v0.2.0
S202	tarfile-unsafe-members	Uses of tarfile.extractall()	Rule has been stable since v0.2.0
S301	suspicious-pickle-usage	pickle and modules that wrap it can be unsafe when used to deserialize untrusted data, possible security issue	Rule has been stable since v0.0.258
S302	suspicious-marshal-usage	Deserialization with the marshal module is possibly dangerous	Rule has been stable since v0.0.258
S303	suspicious-insecure-hash-usage	Use of insecure MD2, MD4, MD5, or SHA1 hash function	Rule has been stable since v0.0.258
S304	suspicious-insecure-cipher-usage	Use of insecure cipher, replace with a known secure cipher such as AES	Rule has been stable since v0.0.258
S305	suspicious-insecure-cipher-mode-usage	Use of insecure block cipher mode, replace with a known secure mode such as CBC or CTR	Rule has been stable since v0.0.258
S306	suspicious-mktemp-usage	Use of insecure and deprecated function (mktemp)	Rule has been stable since v0.0.258
S307	suspicious-eval-usage	Use of possibly insecure function; consider using ast.literal_eval	Rule has been stable since v0.0.258
S308	suspicious-mark-safe-usage	Use of mark_safe may expose cross-site scripting vulnerabilities	Rule has been stable since v0.0.258
S310	suspicious-url-open-usage	Audit URL open for permitted schemes. Allowing use of file: or custom schemes is often unexpected.	Rule has been stable since v0.0.258
S311	suspicious-non-cryptographic-random-usage	Standard pseudo-random generators are not suitable for cryptographic purposes	Rule has been stable since v0.0.258
S312	suspicious-telnet-usage	Telnet is considered insecure. Use SSH or some other encrypted protocol.	Rule has been stable since v0.0.258
S313	suspicious-xmlc-element-tree-usage	Using xml to parse untrusted data is known to be vulnerable to XML attacks; use defusedxml equivalents	Rule has been stable since v0.0.258
S314	suspicious-xml-element-tree-usage	Using xml to parse untrusted data is known to be vulnerable to XML attacks; use defusedxml equivalents	Rule has been stable since v0.0.258
S315	suspicious-xml-expat-reader-usage	Using xml to parse untrusted data is known to be vulnerable to XML attacks; use defusedxml equivalents	Rule has been stable since v0.0.258
S316	suspicious-xml-expat-builder-usage	Using xml to parse untrusted data is known to be vulnerable to XML attacks; use defusedxml equivalents	Rule has been stable since v0.0.258
S317	suspicious-xml-sax-usage	Using xml to parse untrusted data is known to be vulnerable to XML attacks; use defusedxml equivalents	Rule has been stable since v0.0.258
S318	suspicious-xml-mini-dom-usage	Using xml to parse untrusted data is known to be vulnerable to XML attacks; use defusedxml equivalents	Rule has been stable since v0.0.258
S319	suspicious-xml-pull-dom-usage	Using xml to parse untrusted data is known to be vulnerable to XML attacks; use defusedxml equivalents	Rule has been stable since v0.0.258
S320	suspicious-xmle-tree-usage	Using lxml to parse untrusted data is known to be vulnerable to XML attacks	❌Rule was removed in 0.12.0
S321	suspicious-ftp-lib-usage	FTP-related functions are being called. FTP is considered insecure. Use SSH/SFTP/SCP or some other encrypted protocol.	Rule has been stable since v0.0.258
S323	suspicious-unverified-context-usage	Python allows using an insecure context via the _create_unverified_context that reverts to the previous behavior that does not validate certificates or perform hostname checks.	Rule has been stable since v0.0.258
S324	hashlib-insecure-hash-function	Probable use of insecure hash functions in {library}: {string}	Rule has been stable since v0.0.212
S401	suspicious-telnetlib-import	telnetlib and related modules are considered insecure. Use SSH or another encrypted protocol.	🧪Rule has been in preview since v0.1.12
S402	suspicious-ftplib-import	ftplib and related modules are considered insecure. Use SSH, SFTP, SCP, or another encrypted protocol.	🧪Rule has been in preview since v0.1.12
S403	suspicious-pickle-import	pickle, cPickle, dill, and shelve modules are possibly insecure	🧪Rule has been in preview since v0.1.12
S404	suspicious-subprocess-import	subprocess module is possibly insecure	🧪Rule has been in preview since v0.1.12
S405	suspicious-xml-etree-import	xml.etree methods are vulnerable to XML attacks	🧪Rule has been in preview since v0.1.12
S406	suspicious-xml-sax-import	xml.sax methods are vulnerable to XML attacks	🧪Rule has been in preview since v0.1.12
S407	suspicious-xml-expat-import	xml.dom.expatbuilder is vulnerable to XML attacks	🧪Rule has been in preview since v0.1.12
S408	suspicious-xml-minidom-import	xml.dom.minidom is vulnerable to XML attacks	🧪Rule has been in preview since v0.1.12
S409	suspicious-xml-pulldom-import	xml.dom.pulldom is vulnerable to XML attacks	🧪Rule has been in preview since v0.1.12
S410	suspicious-lxml-import	lxml is vulnerable to XML attacks	❌Rule was removed in v0.3.0
S411	suspicious-xmlrpc-import	XMLRPC is vulnerable to remote XML attacks	🧪Rule has been in preview since v0.1.12
S412	suspicious-httpoxy-import	httpoxy is a set of vulnerabilities that affect application code running inCGI, or CGI-like environments. The use of CGI for web applications should be avoided	🧪Rule has been in preview since v0.1.12
S413	suspicious-pycrypto-import	pycrypto library is known to have publicly disclosed buffer overflow vulnerability	🧪Rule has been in preview since v0.1.12
S415	suspicious-pyghmi-import	An IPMI-related module is being imported. Prefer an encrypted protocol over IPMI.	🧪Rule has been in preview since v0.1.12
S501	request-with-no-cert-validation	Probable use of {string} call with verify=False disabling SSL certificate checks	Rule has been stable since v0.0.213
S502	ssl-insecure-version	Call made with insecure SSL protocol: {protocol}	Rule has been stable since v0.2.0
S503	ssl-with-bad-defaults	Argument default set to insecure SSL protocol: {protocol}	Rule has been stable since v0.2.0
S504	ssl-with-no-version	ssl.wrap_socket called without an `ssl_version``	Rule has been stable since v0.2.0
S505	weak-cryptographic-key	{cryptographic_key} key sizes below {minimum_key_size} bits are considered breakable	Rule has been stable since v0.2.0
S506	unsafe-yaml-load	Probable use of unsafe loader {name} with yaml.load. Allows instantiation of arbitrary objects. Consider yaml.safe_load.	Rule has been stable since v0.0.212
S507	ssh-no-host-key-verification	Paramiko call with policy set to automatically trust the unknown host key	Rule has been stable since v0.2.0
S508	snmp-insecure-version	The use of SNMPv1 and SNMPv2 is insecure. Use SNMPv3 if able.	Rule has been stable since v0.0.218
S509	snmp-weak-cryptography	You should not use SNMPv3 without encryption. noAuthNoPriv & authNoPriv is insecure.	Rule has been stable since v0.0.218
S601	paramiko-call	Possible shell injection via Paramiko call; check inputs are properly sanitized	Rule has been stable since v0.0.270
S602	subprocess-popen-with-shell-equals-true	subprocess call with shell=True seems safe, but may be changed in the future; consider rewriting without shell	Rule has been stable since v0.0.262
S603	subprocess-without-shell-equals-true	subprocess call: check for execution of untrusted input	Rule has been stable since v0.0.262
S604	call-with-shell-equals-true	Function call with shell=True parameter identified, security issue	Rule has been stable since v0.0.262
S605	start-process-with-a-shell	Starting a process with a shell: seems safe, but may be changed in the future; consider rewriting without shell	Rule has been stable since v0.0.262
S606	start-process-with-no-shell	Starting a process without a shell	Rule has been stable since v0.0.262
S607	start-process-with-partial-path	Starting a process with a partial executable path	Rule has been stable since v0.0.262
S608	hardcoded-sql-expression	Possible SQL injection vector through string-based query construction	Rule has been stable since v0.0.245
S609	unix-command-wildcard-injection	Possible wildcard injection in call due to * usage	Rule has been stable since v0.0.271
S610	django-extra	Use of Django extra can lead to SQL injection vulnerabilities	Rule has been stable since 0.5.0
S611	django-raw-sql	Use of RawSQL can lead to SQL injection vulnerabilities	Rule has been stable since v0.2.0
S612	logging-config-insecure-listen	Use of insecure logging.config.listen detected	Rule has been stable since v0.0.231
S701	jinja2-autoescape-false	Using jinja2 templates with autoescape=False is dangerous and can lead to XSS. Ensure autoescape=True or use the select_autoescape function.	Rule has been stable since v0.0.220
S702	mako-templates	Mako templates allow HTML and JavaScript rendering by default and are inherently open to XSS attacks	Rule has been stable since v0.2.0
S704	unsafe-markup-use	Unsafe use of {name} detected	Rule has been stable since 0.10.0

flake8-blind-except (BLE)

For more, see flake8-blind-except on PyPI.

Code	Name	Message	Fix/Status
BLE001	blind-except	Do not catch blind exception: {name}	Rule has been stable since v0.0.127

flake8-boolean-trap (FBT)

For more, see flake8-boolean-trap on PyPI.

For related settings, see flake8-boolean-trap.

Code	Name	Message	Fix/Status
FBT001	boolean-type-hint-positional-argument	Boolean-typed positional argument in function definition	Rule has been stable since v0.0.127
FBT002	boolean-default-value-positional-argument	Boolean default positional argument in function definition	Rule has been stable since v0.0.127
FBT003	boolean-positional-value-in-call	Boolean positional value in function call	Rule has been stable since v0.0.127

flake8-bugbear (B)

For more, see flake8-bugbear on PyPI.

For related settings, see flake8-bugbear.

Code	Name	Message	Fix/Status
B002	unary-prefix-increment-decrement	Python does not support the unary prefix increment operator (++)	Rule has been stable since v0.0.83
B003	assignment-to-os-environ	Assigning to os.environ doesn't clear the environment	Rule has been stable since v0.0.102
B004	unreliable-callable-check	Using hasattr(x, "__call__") to test if x is callable is unreliable. Use callable(x) for consistent results.	Rule has been stable since v0.0.106🛠️Automatic fix available
B005	strip-with-multi-characters	Using .strip() with multi-character strings is misleading	Rule has been stable since v0.0.106
B006	mutable-argument-default	Do not use mutable data structures for argument defaults	Rule has been stable since v0.0.92🛠️Automatic fix available
B007	unused-loop-control-variable	Loop control variable {name} not used within loop body	Rule has been stable since v0.0.84🛠️Automatic fix available
B008	function-call-in-default-argument	Do not perform function call {name} in argument defaults; instead, perform the call within the function, or read the default from a module-level singleton variable	Rule has been stable since v0.0.102
B009	get-attr-with-constant	Do not call getattr with a constant attribute value. It is not any safer than normal property access.	Rule has been stable since v0.0.110🛠️Automatic fix available
B010	set-attr-with-constant	Do not call setattr with a constant attribute value. It is not any safer than normal property access.	Rule has been stable since v0.0.111🛠️Automatic fix available
B011	assert-false	Do not assert False (python -O removes these calls), raise AssertionError()	Rule has been stable since v0.0.67🛠️Automatic fix available
B012	jump-statement-in-finally	{name} inside finally blocks cause exceptions to be silenced	Rule has been stable since v0.0.116
B013	redundant-tuple-in-exception-handler	A length-one tuple literal is redundant in exception handlers	Rule has been stable since v0.0.89🛠️Automatic fix available
B014	duplicate-handler-exception	Exception handler with duplicate exception: {name}	Rule has been stable since v0.0.67🛠️Automatic fix available
B015	useless-comparison	Pointless comparison. Did you mean to assign a value? Otherwise, prepend assert or remove it.	Rule has been stable since v0.0.102
B016	raise-literal	Cannot raise a literal. Did you intend to return it or raise an Exception?	Rule has been stable since v0.0.102
B017	assert-raises-exception	Do not assert blind exception: {exception}	Rule has been stable since v0.0.83
B018	useless-expression	Found useless expression. Either assign it to a variable or remove it.	Rule has been stable since v0.0.100
B019	cached-instance-method	Use of functools.lru_cache or functools.cache on methods can lead to memory leaks	Rule has been stable since v0.0.114
B020	loop-variable-overrides-iterator	Loop control variable {name} overrides iterable it iterates	Rule has been stable since v0.0.121
B021	f-string-docstring	f-string used as docstring. Python will interpret this as a joined string, rather than a docstring.	Rule has been stable since v0.0.116
B022	useless-contextlib-suppress	No arguments passed to contextlib.suppress. No exceptions will be suppressed and therefore this context manager is redundant	Rule has been stable since v0.0.118
B023	function-uses-loop-variable	Function definition does not bind loop variable {name}	Rule has been stable since v0.0.139
B024	abstract-base-class-without-abstract-method	{name} is an abstract base class, but it has no abstract methods or properties	Rule has been stable since v0.0.118
B025	duplicate-try-block-exception	try-except* block with duplicate exception {name}	Rule has been stable since v0.0.67
B026	star-arg-unpacking-after-keyword-arg	Star-arg unpacking after a keyword argument is strongly discouraged	Rule has been stable since v0.0.109
B027	empty-method-without-abstract-decorator	{name} is an empty method in an abstract base class, but has no abstract decorator	Rule has been stable since v0.0.118
B028	no-explicit-stacklevel	No explicit stacklevel keyword argument found	Rule has been stable since v0.0.257🛠️Automatic fix available
B029	except-with-empty-tuple	Using except* (): with an empty tuple does not catch anything; add exceptions to handle	Rule has been stable since v0.0.250
B030	except-with-non-exception-classes	except* handlers should only be exception classes or tuples of exception classes	Rule has been stable since v0.0.255
B031	reuse-of-groupby-generator	Using the generator returned from itertools.groupby() more than once will do nothing on the second usage	Rule has been stable since v0.0.260
B032	unintentional-type-annotation	Possible unintentional type annotation (using :). Did you mean to assign (using =)?	Rule has been stable since v0.0.250
B033	duplicate-value	Sets should not contain duplicate item {value}	Rule has been stable since v0.0.271🛠️Automatic fix available
B034	re-sub-positional-args	{method} should pass {param_name} and flags as keyword arguments to avoid confusion due to unintuitive argument positions	Rule has been stable since v0.0.278
B035	static-key-dict-comprehension	Dictionary comprehension uses static key: {key}	Rule has been stable since v0.2.0
B039	mutable-contextvar-default	Do not use mutable data structures for ContextVar defaults	Rule has been stable since 0.8.0
B043	del-attr-with-constant	Do not call delattr with a constant attribute value. It is not any safer than normal property deletion.	🧪Rule has been in preview since 0.15.6🛠️Automatic fix available
B901	return-in-generator	Using yield and return {value} in a generator function can lead to confusing behavior	🧪Rule has been in preview since v0.4.8
B903	class-as-data-structure	Class could be dataclass or namedtuple	🧪Rule has been in preview since 0.9.0
B904	raise-without-from-inside-except	Within an except* clause, raise exceptions with raise ... from err or raise ... from None to distinguish them from errors in exception handling	Rule has been stable since v0.0.138
B905	zip-without-explicit-strict	zip() without an explicit strict= parameter	Rule has been stable since v0.0.167🛠️Automatic fix available
B909	loop-iterator-mutation	Mutation to loop iterable {name} during iteration	🧪Rule has been in preview since v0.3.7
B911	batched-without-explicit-strict	itertools.batched() without an explicit strict parameter	Rule has been stable since 0.10.0
B912	map-without-explicit-strict	map() without an explicit strict= parameter	Rule has been stable since 0.15.0🛠️Automatic fix available

flake8-builtins (A)

For more, see flake8-builtins on PyPI.

For related settings, see flake8-builtins.

Code	Name	Message	Fix/Status
A001	builtin-variable-shadowing	Variable {name} is shadowing a Python builtin	Rule has been stable since v0.0.48
A002	builtin-argument-shadowing	Function argument {name} is shadowing a Python builtin	Rule has been stable since v0.0.48
A003	builtin-attribute-shadowing	Python builtin is shadowed by class attribute {name} from {row}	Rule has been stable since v0.0.48
A004	builtin-import-shadowing	Import {name} is shadowing a Python builtin	Rule has been stable since 0.8.0
A005	stdlib-module-shadowing	Module {name} shadows a Python standard-library module	Rule has been stable since 0.9.0
A006	builtin-lambda-argument-shadowing	Lambda argument {name} is shadowing a Python builtin	Rule has been stable since 0.9.0

flake8-commas (COM)

For more, see flake8-commas on PyPI.

Code	Name	Message	Fix/Status
COM812	missing-trailing-comma	Trailing comma missing	Rule has been stable since v0.0.223🛠️Automatic fix available
COM818	trailing-comma-on-bare-tuple	Trailing comma on bare tuple prohibited	Rule has been stable since v0.0.223
COM819	prohibited-trailing-comma	Trailing comma prohibited	Rule has been stable since v0.0.223🛠️Automatic fix available

flake8-comprehensions (C4)

For more, see flake8-comprehensions on PyPI.

For related settings, see flake8-comprehensions.

Code	Name	Message	Fix/Status
C400	unnecessary-generator-list	Unnecessary generator (rewrite using list())	Rule has been stable since v0.0.61🛠️Automatic fix available
C401	unnecessary-generator-set	Unnecessary generator (rewrite using set())	Rule has been stable since v0.0.61🛠️Automatic fix available
C402	unnecessary-generator-dict	Unnecessary generator (rewrite as a dict comprehension)	Rule has been stable since v0.0.61🛠️Automatic fix available
C403	unnecessary-list-comprehension-set	Unnecessary list comprehension (rewrite as a set comprehension)	Rule has been stable since v0.0.58🛠️Automatic fix available
C404	unnecessary-list-comprehension-dict	Unnecessary list comprehension (rewrite as a dict comprehension)	Rule has been stable since v0.0.58🛠️Automatic fix available
C405	unnecessary-literal-set	Unnecessary {kind} literal (rewrite as a set literal)	Rule has been stable since v0.0.61🛠️Automatic fix available
C406	unnecessary-literal-dict	Unnecessary {obj_type} literal (rewrite as a dict literal)	Rule has been stable since v0.0.61🛠️Automatic fix available
C408	unnecessary-collection-call	Unnecessary {kind}() call (rewrite as a literal)	Rule has been stable since v0.0.61🛠️Automatic fix available
C409	unnecessary-literal-within-tuple-call	Unnecessary list literal passed to tuple() (rewrite as a tuple literal)	Rule has been stable since v0.0.66🛠️Automatic fix available
C410	unnecessary-literal-within-list-call	Unnecessary list literal passed to list() (remove the outer call to list())	Rule has been stable since v0.0.66🛠️Automatic fix available
C411	unnecessary-list-call	Unnecessary list() call (remove the outer call to list())	Rule has been stable since v0.0.73🛠️Automatic fix available
C413	unnecessary-call-around-sorted	Unnecessary {func}() call around sorted()	Rule has been stable since v0.0.73🛠️Automatic fix available
C414	unnecessary-double-cast-or-process	Unnecessary {inner}() call within {outer}()	Rule has been stable since v0.0.70🛠️Automatic fix available
C415	unnecessary-subscript-reversal	Unnecessary subscript reversal of iterable within {func}()	Rule has been stable since v0.0.64
C416	unnecessary-comprehension	Unnecessary {kind} comprehension (rewrite using {kind}())	Rule has been stable since v0.0.73🛠️Automatic fix available
C417	unnecessary-map	Unnecessary map() usage (rewrite using a {object_type})	Rule has been stable since v0.0.74🛠️Automatic fix available
C418	unnecessary-literal-within-dict-call	Unnecessary dict {kind} passed to dict() (remove the outer call to dict())	Rule has been stable since v0.0.262🛠️Automatic fix available
C419	unnecessary-comprehension-in-call	Unnecessary list comprehension	Rule has been stable since v0.0.262🛠️Automatic fix available
C420	unnecessary-dict-comprehension-for-iterable	Unnecessary dict comprehension for iterable; use dict.fromkeys instead	Rule has been stable since 0.10.0🛠️Automatic fix available

flake8-copyright (CPY)

For more, see flake8-copyright on PyPI.

For related settings, see flake8-copyright.

Code	Name	Message	Fix/Status
CPY001	missing-copyright-notice	Missing copyright notice at top of file	🧪Rule has been in preview since v0.0.273

flake8-datetimez (DTZ)

For more, see flake8-datetimez on PyPI.

Code	Name	Message	Fix/Status
DTZ001	call-datetime-without-tzinfo	datetime.datetime() called without a tzinfo argument	Rule has been stable since v0.0.188
DTZ002	call-datetime-today	datetime.datetime.today() used	Rule has been stable since v0.0.188
DTZ003	call-datetime-utcnow	datetime.datetime.utcnow() used	Rule has been stable since v0.0.188
DTZ004	call-datetime-utcfromtimestamp	datetime.datetime.utcfromtimestamp() used	Rule has been stable since v0.0.188
DTZ005	call-datetime-now-without-tzinfo	datetime.datetime.now() called without a tz argument	Rule has been stable since v0.0.188
DTZ006	call-datetime-fromtimestamp	datetime.datetime.fromtimestamp() called without a tz argument	Rule has been stable since v0.0.188
DTZ007	call-datetime-strptime-without-zone	Naive datetime constructed using datetime.datetime.strptime() without %z	Rule has been stable since v0.0.188
DTZ011	call-date-today	datetime.date.today() used	Rule has been stable since v0.0.188
DTZ012	call-date-fromtimestamp	datetime.date.fromtimestamp() used	Rule has been stable since v0.0.188
DTZ901	datetime-min-max	Use of datetime.datetime.{min_max} without timezone information	Rule has been stable since 0.10.0

flake8-debugger (T10)

For more, see flake8-debugger on PyPI.

Code	Name	Message	Fix/Status
T100	debugger	Trace found: {name} used	Rule has been stable since v0.0.141

flake8-django (DJ)

For more, see flake8-django on PyPI.

Code	Name	Message	Fix/Status
DJ001	django-nullable-model-string-field	Avoid using null=True on string-based fields such as {field_name}	Rule has been stable since v0.0.246
DJ003	django-locals-in-render-function	Avoid passing locals() as context to a render function	Rule has been stable since v0.0.253
DJ006	django-exclude-with-model-form	Do not use exclude with ModelForm, use fields instead	Rule has been stable since v0.0.253
DJ007	django-all-with-model-form	Do not use __all__ with ModelForm, use fields instead	Rule has been stable since v0.0.253
DJ008	django-model-without-dunder-str	Model does not define __str__ method	Rule has been stable since v0.0.246
DJ012	django-unordered-body-content-in-model	Order of model's inner classes, methods, and fields does not follow the Django Style Guide: {element_type} should come before {prev_element_type}	Rule has been stable since v0.0.258
DJ013	django-non-leading-receiver-decorator	@receiver decorator must be on top of all the other decorators	Rule has been stable since v0.0.246

flake8-errmsg (EM)

For more, see flake8-errmsg on PyPI.

For related settings, see flake8-errmsg.

Code	Name	Message	Fix/Status
EM101	raw-string-in-exception	Exception must not use a string literal, assign to variable first	Rule has been stable since v0.0.183🛠️Automatic fix available
EM102	f-string-in-exception	Exception must not use an f-string literal, assign to variable first	Rule has been stable since v0.0.183🛠️Automatic fix available
EM103	dot-format-in-exception	Exception must not use a .format() string directly, assign to variable first	Rule has been stable since v0.0.183🛠️Automatic fix available

flake8-executable (EXE)

For more, see flake8-executable on PyPI.

Code	Name	Message	Fix/Status
EXE001	shebang-not-executable	Shebang is present but file is not executable	Rule has been stable since v0.0.233
EXE002	shebang-missing-executable-file	The file is executable but no shebang is present	Rule has been stable since v0.0.233
EXE003	shebang-missing-python	Shebang should contain python, pytest, or uv run	Rule has been stable since v0.0.229
EXE004	shebang-leading-whitespace	Avoid whitespace before shebang	Rule has been stable since v0.0.229🛠️Automatic fix available
EXE005	shebang-not-first-line	Shebang should be at the beginning of the file	Rule has been stable since v0.0.229

flake8-fixme (FIX)

For more, see flake8-fixme on GitHub.

Code	Name	Message	Fix/Status
FIX001	line-contains-fixme	Line contains FIXME, consider resolving the issue	Rule has been stable since v0.0.272
FIX002	line-contains-todo	Line contains TODO, consider resolving the issue	Rule has been stable since v0.0.272
FIX003	line-contains-xxx	Line contains XXX, consider resolving the issue	Rule has been stable since v0.0.272
FIX004	line-contains-hack	Line contains HACK, consider resolving the issue	Rule has been stable since v0.0.272

flake8-future-annotations (FA)

For more, see flake8-future-annotations on PyPI.

Code	Name	Message	Fix/Status
FA100	future-rewritable-type-annotation	Add from __future__ import annotations to simplify {name}	Rule has been stable since v0.0.269🛠️Automatic fix available
FA102	future-required-type-annotation	Missing from __future__ import annotations, but uses {reason}	Rule has been stable since v0.0.271🛠️Automatic fix available

flake8-gettext (INT)

For more, see flake8-gettext on PyPI.

For related settings, see flake8-gettext.

Code	Name	Message	Fix/Status
INT001	f-string-in-get-text-func-call	f-string in plural argument is resolved before function call	Rule has been stable since v0.0.260
INT002	format-in-get-text-func-call	format method in plural argument is resolved before function call	Rule has been stable since v0.0.260
INT003	printf-in-get-text-func-call	printf-style format in plural argument is resolved before function call	Rule has been stable since v0.0.260

flake8-implicit-str-concat (ISC)

For more, see flake8-implicit-str-concat on PyPI.

For related settings, see flake8-implicit-str-concat.

Code	Name	Message	Fix/Status
ISC001	single-line-implicit-string-concatenation	Implicitly concatenated string literals on one line	Rule has been stable since v0.0.201🛠️Automatic fix available
ISC002	multi-line-implicit-string-concatenation	Implicitly concatenated string literals over multiple lines	Rule has been stable since v0.0.201
ISC003	explicit-string-concatenation	Explicitly concatenated string should be implicitly concatenated	Rule has been stable since v0.0.201🛠️Automatic fix available
ISC004	implicit-string-concatenation-in-collection-literal	Unparenthesized implicit string concatenation in collection	🧪Rule has been in preview since 0.14.10🛠️Automatic fix available

flake8-import-conventions (ICN)

For more, see flake8-import-conventions on GitHub.

For related settings, see flake8-import-conventions.

Code	Name	Message	Fix/Status
ICN001	unconventional-import-alias	{name} should be imported as {asname}	Rule has been stable since v0.0.166🛠️Automatic fix available
ICN002	banned-import-alias	{name} should not be imported as {asname}	Rule has been stable since v0.0.262
ICN003	banned-import-from	Members of {name} should not be imported explicitly	Rule has been stable since v0.0.263

flake8-logging (LOG)

For more, see flake8-logging on PyPI.

Code	Name	Message	Fix/Status
LOG001	direct-logger-instantiation	Use logging.getLogger() to instantiate loggers	Rule has been stable since v0.2.0🛠️Automatic fix available
LOG002	invalid-get-logger-argument	Use __name__ with logging.getLogger()	Rule has been stable since v0.2.0🛠️Automatic fix available
LOG004	log-exception-outside-except-handler	.exception() call outside exception handlers	🧪Rule has been in preview since 0.9.5🛠️Automatic fix available
LOG007	exception-without-exc-info	Use of logging.exception with falsy exc_info	Rule has been stable since v0.2.0
LOG009	undocumented-warn	Use of undocumented logging.WARN constant	Rule has been stable since v0.2.0🛠️Automatic fix available
LOG014	exc-info-outside-except-handler	exc_info= outside exception handlers	Rule has been stable since 0.12.0🛠️Automatic fix available
LOG015	root-logger-call	{}() call on root logger	Rule has been stable since 0.10.0

flake8-logging-format (G)

For more, see flake8-logging-format on PyPI.

Code	Name	Message	Fix/Status
G001	logging-string-format	Logging statement uses str.format	Rule has been stable since v0.0.236
G002	logging-percent-format	Logging statement uses %	Rule has been stable since v0.0.236
G003	logging-string-concat	Logging statement uses +	Rule has been stable since v0.0.236
G004	logging-f-string	Logging statement uses f-string	Rule has been stable since v0.0.236🛠️Automatic fix available
G010	logging-warn	Logging statement uses warn instead of warning	Rule has been stable since v0.0.236🛠️Automatic fix available
G101	logging-extra-attr-clash	Logging statement uses an extra field that clashes with a LogRecord field: {key}	Rule has been stable since v0.0.236
G201	logging-exc-info	Logging .exception(...) should be used instead of .error(..., exc_info=True)	Rule has been stable since v0.0.236
G202	logging-redundant-exc-info	Logging statement has redundant exc_info	Rule has been stable since v0.0.236

flake8-no-pep420 (INP)

For more, see flake8-no-pep420 on PyPI.

Code	Name	Message	Fix/Status
INP001	implicit-namespace-package	File {filename} is part of an implicit namespace package. Add an __init__.py.	Rule has been stable since v0.0.225

flake8-pie (PIE)

For more, see flake8-pie on PyPI.

Code	Name	Message	Fix/Status
PIE790	unnecessary-placeholder	Unnecessary pass statement	Rule has been stable since v0.0.208🛠️Automatic fix available
PIE794	duplicate-class-field-definition	Class field {name} is defined multiple times	Rule has been stable since v0.0.208🛠️Automatic fix available
PIE796	non-unique-enums	Enum contains duplicate value: {value}	Rule has been stable since v0.0.224
PIE800	unnecessary-spread	Unnecessary spread **	Rule has been stable since v0.0.231🛠️Automatic fix available
PIE804	unnecessary-dict-kwargs	Unnecessary dict kwargs	Rule has been stable since v0.0.231🛠️Automatic fix available
PIE807	reimplemented-container-builtin	Prefer {container} over useless lambda	Rule has been stable since v0.0.208🛠️Automatic fix available
PIE808	unnecessary-range-start	Unnecessary start argument in range	Rule has been stable since v0.0.286🛠️Automatic fix available
PIE810	multiple-starts-ends-with	Call {attr} once with a tuple	Rule has been stable since v0.0.243🛠️Automatic fix available

flake8-print (T20)

For more, see flake8-print on PyPI.

Code	Name	Message	Fix/Status
T201	print	print found	Rule has been stable since v0.0.57🛠️Automatic fix available
T203	p-print	pprint found	Rule has been stable since v0.0.57🛠️Automatic fix available

flake8-pyi (PYI)

For more, see flake8-pyi on PyPI.

Code	Name	Message	Fix/Status
PYI001	unprefixed-type-param	Name of private {kind} must start with _	Rule has been stable since v0.0.245
PYI002	complex-if-statement-in-stub	if test must be a simple comparison against sys.platform or sys.version_info	Rule has been stable since v0.0.276
PYI003	unrecognized-version-info-check	Unrecognized sys.version_info check	Rule has been stable since v0.0.276
PYI004	patch-version-comparison	Version comparison must use only major and minor version	Rule has been stable since v0.0.276
PYI005	wrong-tuple-length-version-comparison	Version comparison must be against a length-{expected_length} tuple	Rule has been stable since v0.0.276
PYI006	bad-version-info-comparison	Use < or >= for sys.version_info comparisons	Rule has been stable since v0.0.254
PYI007	unrecognized-platform-check	Unrecognized sys.platform check	Rule has been stable since v0.0.246
PYI008	unrecognized-platform-name	Unrecognized platform {platform}	Rule has been stable since v0.0.246
PYI009	pass-statement-stub-body	Empty body should contain ..., not pass	Rule has been stable since v0.0.253🛠️Automatic fix available
PYI010	non-empty-stub-body	Function body must contain only ...	Rule has been stable since v0.0.253🛠️Automatic fix available
PYI011	typed-argument-default-in-stub	Only simple default values allowed for typed arguments	Rule has been stable since v0.0.253🛠️Automatic fix available
PYI012	pass-in-class-body	Class body must not contain pass	Rule has been stable since v0.0.260🛠️Automatic fix available
PYI013	ellipsis-in-non-empty-class-body	Non-empty class body must not contain ...	Rule has been stable since v0.0.270🛠️Automatic fix available
PYI014	argument-default-in-stub	Only simple default values allowed for arguments	Rule has been stable since v0.0.253🛠️Automatic fix available
PYI015	assignment-default-in-stub	Only simple default values allowed for assignments	Rule has been stable since v0.0.260🛠️Automatic fix available
PYI016	duplicate-union-member	Duplicate union member {}	Rule has been stable since v0.0.262🛠️Automatic fix available
PYI017	complex-assignment-in-stub	Stubs should not contain assignments to attributes or multiple targets	Rule has been stable since v0.0.279
PYI018	unused-private-type-var	Private {type_var_like_kind} {type_var_like_name} is never used	Rule has been stable since v0.0.281🛠️Automatic fix available
PYI019	custom-type-var-for-self	Use Self instead of custom TypeVar {}	Rule has been stable since v0.0.283🛠️Automatic fix available
PYI020	quoted-annotation-in-stub	Quoted annotations should not be included in stubs	Rule has been stable since v0.0.265🛠️Automatic fix available
PYI021	docstring-in-stub	Docstrings should not be included in stubs	Rule has been stable since v0.0.253🛠️Automatic fix available
PYI024	collections-named-tuple	Use typing.NamedTuple instead of collections.namedtuple	Rule has been stable since v0.0.271
PYI025	unaliased-collections-abc-set-import	Use from collections.abc import Set as AbstractSet to avoid confusion with the set builtin	Rule has been stable since v0.0.271🛠️Automatic fix available
PYI026	type-alias-without-annotation	Use {module}.TypeAlias for type alias, e.g., {name}: TypeAlias = {value}	Rule has been stable since v0.0.279🛠️Automatic fix available
PYI029	str-or-repr-defined-in-stub	Defining {name} in a stub is almost always redundant	Rule has been stable since v0.0.271🛠️Automatic fix available
PYI030	unnecessary-literal-union	Multiple literal members in a union. Use a single literal, e.g. Literal[{}]	Rule has been stable since v0.0.278🛠️Automatic fix available
PYI032	any-eq-ne-annotation	Prefer object to Any for the second parameter to {method_name}	Rule has been stable since v0.0.271🛠️Automatic fix available
PYI033	type-comment-in-stub	Don't use type comments in stub file	Rule has been stable since v0.0.254
PYI034	non-self-return-type	__new__ methods usually return self at runtime	Rule has been stable since v0.0.271🛠️Automatic fix available
PYI035	unassigned-special-variable-in-stub	{name} in a stub file must have a value, as it has the same semantics as {name} at runtime	Rule has been stable since v0.0.271
PYI036	bad-exit-annotation	Star-args in {method_name} should be annotated with object	Rule has been stable since v0.0.279🛠️Automatic fix available
PYI041	redundant-numeric-union	Use {supertype} instead of {subtype} | {supertype}	Rule has been stable since v0.0.279🛠️Automatic fix available
PYI042	snake-case-type-alias	Type alias {name} should be CamelCase	Rule has been stable since v0.0.265
PYI043	t-suffixed-type-alias	Private type alias {name} should not be suffixed with T (the T suffix implies that an object is a TypeVar)	Rule has been stable since v0.0.265
PYI044	future-annotations-in-stub	from __future__ import annotations has no effect in stub files, since type checkers automatically treat stubs as having those semantics	Rule has been stable since v0.0.273🛠️Automatic fix available
PYI045	iter-method-return-iterable	__aiter__ methods should return an AsyncIterator, not an AsyncIterable	Rule has been stable since v0.0.271
PYI046	unused-private-protocol	Private protocol {name} is never used	Rule has been stable since v0.0.281
PYI047	unused-private-type-alias	Private TypeAlias {name} is never used	Rule has been stable since v0.0.281
PYI048	stub-body-multiple-statements	Function body must contain exactly one statement	Rule has been stable since v0.0.271
PYI049	unused-private-typed-dict	Private TypedDict {name} is never used	Rule has been stable since v0.0.281
PYI050	no-return-argument-annotation-in-stub	Prefer {module}.Never over NoReturn for argument annotations	Rule has been stable since v0.0.272
PYI051	redundant-literal-union	Literal[{literal}] is redundant in a union with {builtin_type}	Rule has been stable since v0.0.283
PYI052	unannotated-assignment-in-stub	Need type annotation for {name}	Rule has been stable since v0.0.269
PYI053	string-or-bytes-too-long	String and bytes literals longer than 50 characters are not permitted	Rule has been stable since v0.0.271🛠️Automatic fix available
PYI054	numeric-literal-too-long	Numeric literals with a string representation longer than ten characters are not permitted	Rule has been stable since v0.0.271🛠️Automatic fix available
PYI055	unnecessary-type-union	Multiple type members in a union. Combine them into one, e.g., type[{union_str}].	Rule has been stable since v0.0.283🛠️Automatic fix available
PYI056	unsupported-method-call-on-all	Calling .{name}() on __all__ may not be supported by all type checkers (use += instead)	Rule has been stable since v0.0.281
PYI057	byte-string-usage	Do not use {origin}.ByteString, which has unclear semantics and is deprecated	Rule has been stable since 0.6.0
PYI058	generator-return-from-iter-method	Use {return_type} as the return value for simple {method} methods	Rule has been stable since v0.2.0🛠️Automatic fix available
PYI059	generic-not-last-base-class	Generic[] should always be the last base class	Rule has been stable since 0.13.0🛠️Automatic fix available
PYI061	redundant-none-literal	Use None rather than Literal[None]	Rule has been stable since 0.13.0🛠️Automatic fix available
PYI062	duplicate-literal-member	Duplicate literal member {}	Rule has been stable since 0.6.0🛠️Automatic fix available
PYI063	pep484-style-positional-only-parameter	Use PEP 570 syntax for positional-only parameters	Rule has been stable since 0.8.0
PYI064	redundant-final-literal	Final[Literal[{literal}]] can be replaced with a bare Final	Rule has been stable since 0.8.0🛠️Automatic fix available
PYI066	bad-version-info-order	Put branches for newer Python versions first when branching on sys.version_info comparisons	Rule has been stable since 0.8.0

flake8-pytest-style (PT)

For more, see flake8-pytest-style on PyPI.

For related settings, see flake8-pytest-style.

Code	Name	Message	Fix/Status
PT001	pytest-fixture-incorrect-parentheses-style	Use @pytest.fixture{expected} over @pytest.fixture{actual}	Rule has been stable since v0.0.208🛠️Automatic fix available
PT002	pytest-fixture-positional-args	Configuration for fixture {function} specified via positional args, use kwargs	Rule has been stable since v0.0.208
PT003	pytest-extraneous-scope-function	scope='function' is implied in @pytest.fixture()	Rule has been stable since v0.0.208🛠️Automatic fix available
PT004	pytest-missing-fixture-name-underscore	Fixture {function} does not return anything, add leading underscore	❌Rule was removed in 0.8.0
PT005	pytest-incorrect-fixture-name-underscore	Fixture {function} returns a value, remove leading underscore	❌Rule was removed in 0.8.0
PT006	pytest-parametrize-names-wrong-type	Wrong type passed to first argument of pytest.mark.parametrize; expected {expected_string}	Rule has been stable since v0.0.208🛠️Automatic fix available
PT007	pytest-parametrize-values-wrong-type	Wrong values type in pytest.mark.parametrize expected {values} of {row}	Rule has been stable since v0.0.208🛠️Automatic fix available
PT008	pytest-patch-with-lambda	Use return_value= instead of patching with lambda	Rule has been stable since v0.0.208
PT009	pytest-unittest-assertion	Use a regular assert instead of unittest-style {assertion}	Rule has been stable since v0.0.208🛠️Automatic fix available
PT010	pytest-raises-without-exception	Set the expected exception in pytest.raises()	Rule has been stable since v0.0.208
PT011	pytest-raises-too-broad	pytest.raises({exception}) is too broad, set the match parameter or use a more specific exception	Rule has been stable since v0.0.208
PT012	pytest-raises-with-multiple-statements	pytest.raises() block should contain a single simple statement	Rule has been stable since v0.0.208
PT013	pytest-incorrect-pytest-import	Incorrect import of pytest; use import pytest instead	Rule has been stable since v0.0.208
PT014	pytest-duplicate-parametrize-test-cases	Duplicate of test case at index {index} in pytest.mark.parametrize	Rule has been stable since v0.0.285🛠️Automatic fix available
PT015	pytest-assert-always-false	Assertion always fails, replace with pytest.fail()	Rule has been stable since v0.0.208
PT016	pytest-fail-without-message	No message passed to pytest.fail()	Rule has been stable since v0.0.208
PT017	pytest-assert-in-except	Found assertion on exception {name} in except block, use pytest.raises() instead	Rule has been stable since v0.0.208
PT018	pytest-composite-assertion	Assertion should be broken down into multiple parts	Rule has been stable since v0.0.208🛠️Automatic fix available
PT019	pytest-fixture-param-without-value	Fixture {name} without value is injected as parameter, use @pytest.mark.usefixtures instead	Rule has been stable since v0.0.208
PT020	pytest-deprecated-yield-fixture	@pytest.yield_fixture is deprecated, use @pytest.fixture	Rule has been stable since v0.0.208
PT021	pytest-fixture-finalizer-callback	Use yield instead of request.addfinalizer	Rule has been stable since v0.0.208
PT022	pytest-useless-yield-fixture	No teardown in fixture {name}, use return instead of yield	Rule has been stable since v0.0.208🛠️Automatic fix available
PT023	pytest-incorrect-mark-parentheses-style	Use @pytest.mark.{mark_name}{expected_parens} over @pytest.mark.{mark_name}{actual_parens}	Rule has been stable since v0.0.208🛠️Automatic fix available
PT024	pytest-unnecessary-asyncio-mark-on-fixture	pytest.mark.asyncio is unnecessary for fixtures	Rule has been stable since v0.0.208🛠️Automatic fix available
PT025	pytest-erroneous-use-fixtures-on-fixture	pytest.mark.usefixtures has no effect on fixtures	Rule has been stable since v0.0.208🛠️Automatic fix available
PT026	pytest-use-fixtures-without-parameters	Useless pytest.mark.usefixtures without parameters	Rule has been stable since v0.0.208🛠️Automatic fix available
PT027	pytest-unittest-raises-assertion	Use pytest.raises instead of unittest-style {assertion}	Rule has been stable since v0.0.285🛠️Automatic fix available
PT028	pytest-parameter-with-default-argument	Test function parameter {} has default argument	Rule has been stable since 0.12.0
PT029	pytest-warns-without-warning	Set the expected warning in pytest.warns()	🧪Rule has been in preview since 0.9.2
PT030	pytest-warns-too-broad	pytest.warns({warning}) is too broad, set the match parameter or use a more specific warning	Rule has been stable since 0.12.0
PT031	pytest-warns-with-multiple-statements	pytest.warns() block should contain a single simple statement	Rule has been stable since 0.12.0

flake8-quotes (Q)

For more, see flake8-quotes on PyPI.

For related settings, see flake8-quotes.

Code	Name	Message	Fix/Status
Q000	bad-quotes-inline-string	Single quotes found but double quotes preferred	Rule has been stable since v0.0.88🛠️Automatic fix available
Q001	bad-quotes-multiline-string	Single quote multiline found but double quotes preferred	Rule has been stable since v0.0.88🛠️Automatic fix available
Q002	bad-quotes-docstring	Single quote docstring found but double quotes preferred	Rule has been stable since v0.0.88🛠️Automatic fix available
Q003	avoidable-escaped-quote	Change outer quotes to avoid escaping inner quotes	Rule has been stable since v0.0.88🛠️Automatic fix available
Q004	unnecessary-escaped-quote	Unnecessary escape on inner quote character	Rule has been stable since v0.2.0🛠️Automatic fix available

flake8-raise (RSE)

For more, see flake8-raise on PyPI.

Code	Name	Message	Fix/Status
RSE102	unnecessary-paren-on-raise-exception	Unnecessary parentheses on raised exception	Rule has been stable since v0.0.239🛠️Automatic fix available

flake8-return (RET)

For more, see flake8-return on PyPI.

Code	Name	Message	Fix/Status
RET501	unnecessary-return-none	Do not explicitly return None in function if it is the only possible return value	Rule has been stable since v0.0.154🛠️Automatic fix available
RET502	implicit-return-value	Do not implicitly return None in function able to return non-None value	Rule has been stable since v0.0.154🛠️Automatic fix available
RET503	implicit-return	Missing explicit return at the end of function able to return non-None value	Rule has been stable since v0.0.154🛠️Automatic fix available
RET504	unnecessary-assign	Unnecessary assignment to {name} before return statement	Rule has been stable since v0.0.154🛠️Automatic fix available
RET505	superfluous-else-return	Unnecessary {branch} after return statement	Rule has been stable since v0.0.154🛠️Automatic fix available
RET506	superfluous-else-raise	Unnecessary {branch} after raise statement	Rule has been stable since v0.0.154🛠️Automatic fix available
RET507	superfluous-else-continue	Unnecessary {branch} after continue statement	Rule has been stable since v0.0.154🛠️Automatic fix available
RET508	superfluous-else-break	Unnecessary {branch} after break statement	Rule has been stable since v0.0.154🛠️Automatic fix available

flake8-self (SLF)

For more, see flake8-self on PyPI.

For related settings, see flake8-self.

Code	Name	Message	Fix/Status
SLF001	private-member-access	Private member accessed: {access}	Rule has been stable since v0.0.240

flake8-simplify (SIM)

For more, see flake8-simplify on PyPI.

Code	Name	Message	Fix/Status
SIM101	duplicate-isinstance-call	Multiple isinstance calls for {name}, merge into a single call	Rule has been stable since v0.0.212🛠️Automatic fix available
SIM102	collapsible-if	Use a single if statement instead of nested if statements	Rule has been stable since v0.0.211🛠️Automatic fix available
SIM103	needless-bool	Return the condition {condition} directly	Rule has been stable since v0.0.214🛠️Automatic fix available
SIM105	suppressible-exception	Use contextlib.suppress({exception}) instead of try-except-pass	Rule has been stable since v0.0.211🛠️Automatic fix available
SIM107	return-in-try-except-finally	Don't use return in try-except and finally	Rule has been stable since v0.0.211
SIM108	if-else-block-instead-of-if-exp	Use ternary operator {contents} instead of if-else-block	Rule has been stable since v0.0.213🛠️Automatic fix available
SIM109	compare-with-tuple	Use {replacement} instead of multiple equality comparisons	Rule has been stable since v0.0.213🛠️Automatic fix available
SIM110	reimplemented-builtin	Use {replacement} instead of for loop	Rule has been stable since v0.0.211🛠️Automatic fix available
SIM112	uncapitalized-environment-variables	Use capitalized environment variable {expected} instead of {actual}	Rule has been stable since v0.0.218🛠️Automatic fix available
SIM113	enumerate-for-loop	Use enumerate() for index variable {index} in for loop	Rule has been stable since v0.2.0
SIM114	if-with-same-arms	Combine if branches using logical or operator	Rule has been stable since v0.0.246🛠️Automatic fix available
SIM115	open-file-with-context-handler	Use a context manager for opening files	Rule has been stable since v0.0.219
SIM116	if-else-block-instead-of-dict-lookup	Use a dictionary instead of consecutive if statements	Rule has been stable since v0.0.250
SIM117	multiple-with-statements	Use a single with statement with multiple contexts instead of nested with statements	Rule has been stable since v0.0.211🛠️Automatic fix available
SIM118	in-dict-keys	Use key {operator} dict instead of key {operator} dict.keys()	Rule has been stable since v0.0.176🛠️Automatic fix available
SIM201	negate-equal-op	Use {left} != {right} instead of not {left} == {right}	Rule has been stable since v0.0.213🛠️Automatic fix available
SIM202	negate-not-equal-op	Use {left} == {right} instead of not {left} != {right}	Rule has been stable since v0.0.213🛠️Automatic fix available
SIM208	double-negation	Use {expr} instead of not (not {expr})	Rule has been stable since v0.0.213🛠️Automatic fix available
SIM210	if-expr-with-true-false	Remove unnecessary True if ... else False	Rule has been stable since v0.0.214🛠️Automatic fix available
SIM211	if-expr-with-false-true	Use not ... instead of False if ... else True	Rule has been stable since v0.0.214🛠️Automatic fix available
SIM212	if-expr-with-twisted-arms	Use {expr_else} if {expr_else} else {expr_body} instead of {expr_body} if not {expr_else} else {expr_else}	Rule has been stable since v0.0.214🛠️Automatic fix available
SIM220	expr-and-not-expr	Use False instead of {name} and not {name}	Rule has been stable since v0.0.211🛠️Automatic fix available
SIM221	expr-or-not-expr	Use True instead of {name} or not {name}	Rule has been stable since v0.0.211🛠️Automatic fix available
SIM222	expr-or-true	Use {expr} instead of {replaced}	Rule has been stable since v0.0.208🛠️Automatic fix available
SIM223	expr-and-false	Use {expr} instead of {replaced}	Rule has been stable since v0.0.208🛠️Automatic fix available
SIM300	yoda-conditions	Yoda condition detected	Rule has been stable since v0.0.207🛠️Automatic fix available
SIM401	if-else-block-instead-of-dict-get	Use {contents} instead of an if block	Rule has been stable since v0.0.219🛠️Automatic fix available
SIM905	split-static-string	Consider using a list literal instead of str.{}	Rule has been stable since 0.10.0🛠️Automatic fix available
SIM910	dict-get-with-none-default	Use {expected} instead of {actual}	Rule has been stable since v0.0.261🛠️Automatic fix available
SIM911	zip-dict-keys-and-values	Use {expected} instead of {actual}	Rule has been stable since v0.2.0🛠️Automatic fix available

flake8-slots (SLOT)

For more, see flake8-slots on PyPI.

Code	Name	Message	Fix/Status
SLOT000	no-slots-in-str-subclass	Subclasses of str should define __slots__	Rule has been stable since v0.0.273
SLOT001	no-slots-in-tuple-subclass	Subclasses of tuple should define __slots__	Rule has been stable since v0.0.273
SLOT002	no-slots-in-namedtuple-subclass	Subclasses of {namedtuple_kind} should define __slots__	Rule has been stable since v0.0.273

flake8-tidy-imports (TID)

For more, see flake8-tidy-imports on PyPI.

For related settings, see flake8-tidy-imports.

Code	Name	Message	Fix/Status
TID251	banned-api	{name} is banned: {message}	Rule has been stable since v0.0.201
TID252	relative-imports	Prefer absolute imports over relative imports from parent modules	Rule has been stable since v0.0.169🛠️Automatic fix available
TID253	banned-module-level-imports	{name} is banned at the module level	Rule has been stable since v0.0.285
TID254	lazy-import-mismatch	{name} should be imported lazily	🧪Rule has been in preview since 0.15.6🛠️Automatic fix available

flake8-todos (TD)

For more, see flake8-todos on GitHub.

Code	Name	Message	Fix/Status
TD001	invalid-todo-tag	Invalid TODO tag: {tag}	Rule has been stable since v0.0.269
TD002	missing-todo-author	Missing author in TODO; try: # TODO(<author_name>): ... or # TODO @<author_name>: ...	Rule has been stable since v0.0.269
TD003	missing-todo-link	Missing issue link for this TODO	Rule has been stable since v0.0.269
TD004	missing-todo-colon	Missing colon in TODO	Rule has been stable since v0.0.269
TD005	missing-todo-description	Missing issue description after TODO	Rule has been stable since v0.0.269
TD006	invalid-todo-capitalization	Invalid TODO capitalization: {tag} should be TODO	Rule has been stable since v0.0.269🛠️Automatic fix available
TD007	missing-space-after-todo-colon	Missing space after colon in TODO	Rule has been stable since v0.0.269

flake8-type-checking (TC)

For more, see flake8-type-checking on PyPI.

For related settings, see flake8-type-checking.

Code	Name	Message	Fix/Status
TC001	typing-only-first-party-import	Move application import {} into a type-checking block	Rule has been stable since 0.8.0🛠️Automatic fix available
TC002	typing-only-third-party-import	Move third-party import {} into a type-checking block	Rule has been stable since 0.8.0🛠️Automatic fix available
TC003	typing-only-standard-library-import	Move standard library import {} into a type-checking block	Rule has been stable since 0.8.0🛠️Automatic fix available
TC004	runtime-import-in-type-checking-block	Move import {qualified_name} out of type-checking block. Import is used for more than type hinting.	Rule has been stable since 0.8.0🛠️Automatic fix available
TC005	empty-type-checking-block	Found empty type-checking block	Rule has been stable since 0.8.0🛠️Automatic fix available
TC006	runtime-cast-value	Add quotes to type expression in typing.cast()	Rule has been stable since 0.10.0🛠️Automatic fix available
TC007	unquoted-type-alias	Add quotes to type alias	Rule has been stable since 0.10.0🛠️Automatic fix available
TC008	quoted-type-alias	Remove quotes from type alias	🧪Rule has been in preview since 0.8.1🛠️Automatic fix available
TC010	runtime-string-union	Invalid string member in X | Y-style union type	Rule has been stable since 0.8.0

flake8-unused-arguments (ARG)

For more, see flake8-unused-arguments on PyPI.

For related settings, see flake8-unused-arguments.

Code	Name	Message	Fix/Status
ARG001	unused-function-argument	Unused function argument: {name}	Rule has been stable since v0.0.168
ARG002	unused-method-argument	Unused method argument: {name}	Rule has been stable since v0.0.168
ARG003	unused-class-method-argument	Unused class method argument: {name}	Rule has been stable since v0.0.168
ARG004	unused-static-method-argument	Unused static method argument: {name}	Rule has been stable since v0.0.168
ARG005	unused-lambda-argument	Unused lambda argument: {name}	Rule has been stable since v0.0.168

flake8-use-pathlib (PTH)

For more, see flake8-use-pathlib on PyPI.

Code	Name	Message	Fix/Status
PTH100	os-path-abspath	os.path.abspath() should be replaced by Path.resolve()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH101	os-chmod	os.chmod() should be replaced by Path.chmod()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH102	os-mkdir	os.mkdir() should be replaced by Path.mkdir()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH103	os-makedirs	os.makedirs() should be replaced by Path.mkdir(parents=True)	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH104	os-rename	os.rename() should be replaced by Path.rename()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH105	os-replace	os.replace() should be replaced by Path.replace()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH106	os-rmdir	os.rmdir() should be replaced by Path.rmdir()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH107	os-remove	os.remove() should be replaced by Path.unlink()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH108	os-unlink	os.unlink() should be replaced by Path.unlink()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH109	os-getcwd	os.getcwd() should be replaced by Path.cwd()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH110	os-path-exists	os.path.exists() should be replaced by Path.exists()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH111	os-path-expanduser	os.path.expanduser() should be replaced by Path.expanduser()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH112	os-path-isdir	os.path.isdir() should be replaced by Path.is_dir()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH113	os-path-isfile	os.path.isfile() should be replaced by Path.is_file()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH114	os-path-islink	os.path.islink() should be replaced by Path.is_symlink()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH115	os-readlink	os.readlink() should be replaced by Path.readlink()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH116	os-stat	os.stat() should be replaced by Path.stat(), Path.owner(), or Path.group()	Rule has been stable since v0.0.231
PTH117	os-path-isabs	os.path.isabs() should be replaced by Path.is_absolute()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH118	os-path-join	os.{module}.join() should be replaced by Path with / operator	Rule has been stable since v0.0.231
PTH119	os-path-basename	os.path.basename() should be replaced by Path.name	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH120	os-path-dirname	os.path.dirname() should be replaced by Path.parent	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH121	os-path-samefile	os.path.samefile() should be replaced by Path.samefile()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH122	os-path-splitext	os.path.splitext() should be replaced by Path.suffix, Path.stem, and Path.parent	Rule has been stable since v0.0.231
PTH123	builtin-open	open() should be replaced by Path.open()	Rule has been stable since v0.0.231🛠️Automatic fix available
PTH124	py-path	py.path is in maintenance mode, use pathlib instead	Rule has been stable since v0.0.231
PTH201	path-constructor-current-directory	Do not pass the current directory explicitly to Path	Rule has been stable since v0.0.279🛠️Automatic fix available
PTH202	os-path-getsize	os.path.getsize should be replaced by Path.stat().st_size	Rule has been stable since v0.0.279🛠️Automatic fix available
PTH203	os-path-getatime	os.path.getatime should be replaced by Path.stat().st_atime	Rule has been stable since v0.0.279🛠️Automatic fix available
PTH204	os-path-getmtime	os.path.getmtime should be replaced by Path.stat().st_mtime	Rule has been stable since v0.0.279🛠️Automatic fix available
PTH205	os-path-getctime	os.path.getctime should be replaced by Path.stat().st_ctime	Rule has been stable since v0.0.279🛠️Automatic fix available
PTH206	os-sep-split	Replace .split(os.sep) with Path.parts	Rule has been stable since v0.0.281
PTH207	glob	Replace {function} with Path.glob or Path.rglob	Rule has been stable since v0.0.281
PTH208	os-listdir	Use pathlib.Path.iterdir() instead.	Rule has been stable since 0.10.0
PTH210	invalid-pathlib-with-suffix	Invalid suffix passed to .with_suffix()	Rule has been stable since 0.10.0🛠️Automatic fix available
PTH211	os-symlink	os.symlink should be replaced by Path.symlink_to	Rule has been stable since 0.13.0🛠️Automatic fix available

flynt (FLY)

For more, see flynt on PyPI.

Code	Name	Message	Fix/Status
FLY002	static-join-to-f-string	Consider {expression} instead of string join	Rule has been stable since v0.0.266🛠️Automatic fix available

isort (I)

For more, see isort on PyPI.

For related settings, see isort.

Code	Name	Message	Fix/Status
I001	unsorted-imports	Import block is un-sorted or un-formatted	Rule has been stable since v0.0.110🛠️Automatic fix available
I002	missing-required-import	Missing required import: {name}	Rule has been stable since v0.0.218🛠️Automatic fix available

mccabe (C90)

For more, see mccabe on PyPI.

For related settings, see mccabe.

Code	Name	Message	Fix/Status
C901	complex-structure	{name} is too complex ({complexity} > {max_complexity})	Rule has been stable since v0.0.127

NumPy-specific rules (NPY)

Code	Name	Message	Fix/Status
NPY001	numpy-deprecated-type-alias	Type alias np.{type_name} is deprecated, replace with builtin type	Rule has been stable since v0.0.247🛠️Automatic fix available
NPY002	numpy-legacy-random	Replace legacy np.random.{method_name} call with np.random.Generator	Rule has been stable since v0.0.248
NPY003	numpy-deprecated-function	np.{existing} is deprecated; use np.{replacement} instead	Rule has been stable since v0.0.276🛠️Automatic fix available
NPY201	numpy2-deprecation	np.{existing} will be removed in NumPy 2.0. {migration_guide}	Rule has been stable since v0.2.0🛠️Automatic fix available

pandas-vet (PD)

For more, see pandas-vet on PyPI.

Code	Name	Message	Fix/Status
PD002	pandas-use-of-inplace-argument	inplace=True should be avoided; it has inconsistent behavior	Rule has been stable since v0.0.188🛠️Automatic fix available
PD003	pandas-use-of-dot-is-null	.isna is preferred to .isnull; functionality is equivalent	Rule has been stable since v0.0.188
PD004	pandas-use-of-dot-not-null	.notna is preferred to .notnull; functionality is equivalent	Rule has been stable since v0.0.188
PD007	pandas-use-of-dot-ix	.ix is deprecated; use more explicit .loc or .iloc	Rule has been stable since v0.0.188
PD008	pandas-use-of-dot-at	Use .loc instead of .at. If speed is important, use NumPy.	Rule has been stable since v0.0.188
PD009	pandas-use-of-dot-iat	Use .iloc instead of .iat. If speed is important, use NumPy.	Rule has been stable since v0.0.188
PD010	pandas-use-of-dot-pivot-or-unstack	.pivot_table is preferred to .pivot or .unstack; provides same functionality	Rule has been stable since v0.0.188
PD011	pandas-use-of-dot-values	Use .to_numpy() or .array instead of .values	Rule has been stable since v0.0.188
PD012	pandas-use-of-dot-read-table	Use .read_csv instead of .read_table to read CSV files	Rule has been stable since v0.0.188
PD013	pandas-use-of-dot-stack	.melt is preferred to .stack; provides same functionality	Rule has been stable since v0.0.188
PD015	pandas-use-of-pd-merge	Use .merge method instead of pd.merge function. They have equivalent functionality.	Rule has been stable since v0.0.188
PD101	pandas-nunique-constant-series-check	Using series.nunique() for checking that a series is constant is inefficient	Rule has been stable since v0.0.279
PD901	pandas-df-variable-name	Avoid using the generic variable name df for DataFrames	❌Rule was removed in 0.13.0

pep8-naming (N)

For more, see pep8-naming on PyPI.

For related settings, see pep8-naming.

Code	Name	Message	Fix/Status
N801	invalid-class-name	Class name {name} should use CapWords convention	Rule has been stable since v0.0.77
N802	invalid-function-name	Function name {name} should be lowercase	Rule has been stable since v0.0.77
N803	invalid-argument-name	Argument name {name} should be lowercase	Rule has been stable since v0.0.77
N804	invalid-first-argument-name-for-class-method	First argument of a class method should be named cls	Rule has been stable since v0.0.77🛠️Automatic fix available
N805	invalid-first-argument-name-for-method	First argument of a method should be named self	Rule has been stable since v0.0.77🛠️Automatic fix available
N806	non-lowercase-variable-in-function	Variable {name} in function should be lowercase	Rule has been stable since v0.0.89
N807	dunder-function-name	Function name should not start and end with __	Rule has been stable since v0.0.82
N811	constant-imported-as-non-constant	Constant {name} imported as non-constant {asname}	Rule has been stable since v0.0.82
N812	lowercase-imported-as-non-lowercase	Lowercase {name} imported as non-lowercase {asname}	Rule has been stable since v0.0.82
N813	camelcase-imported-as-lowercase	Camelcase {name} imported as lowercase {asname}	Rule has been stable since v0.0.82
N814	camelcase-imported-as-constant	Camelcase {name} imported as constant {asname}	Rule has been stable since v0.0.82
N815	mixed-case-variable-in-class-scope	Variable {name} in class scope should not be mixedCase	Rule has been stable since v0.0.89
N816	mixed-case-variable-in-global-scope	Variable {name} in global scope should not be mixedCase	Rule has been stable since v0.0.89
N817	camelcase-imported-as-acronym	CamelCase {name} imported as acronym {asname}	Rule has been stable since v0.0.82
N818	error-suffix-on-exception-name	Exception name {name} should be named with an Error suffix	Rule has been stable since v0.0.89
N999	invalid-module-name	Invalid module name: '{name}'	Rule has been stable since v0.0.248

Perflint (PERF)

For more, see Perflint on PyPI.

Code	Name	Message	Fix/Status
PERF101	unnecessary-list-cast	Do not cast an iterable to list before iterating over it	Rule has been stable since v0.0.276🛠️Automatic fix available
PERF102	incorrect-dict-iterator	When using only the {subset} of a dict use the {subset}() method	Rule has been stable since v0.0.273🛠️Automatic fix available
PERF203	try-except-in-loop	try-except within a loop incurs performance overhead	Rule has been stable since v0.0.276
PERF401	manual-list-comprehension	Use {message_str} to create a transformed list	Rule has been stable since v0.0.276🛠️Automatic fix available
PERF402	manual-list-copy	Use list or list.copy to create a copy of a list	Rule has been stable since v0.0.276
PERF403	manual-dict-comprehension	Use a dictionary comprehension instead of {modifier} for-loop	Rule has been stable since 0.5.0🛠️Automatic fix available

pycodestyle (E, W)

For more, see pycodestyle on PyPI.

For related settings, see pycodestyle.

Error (E)

Code	Name	Message	Fix/Status
E101	mixed-spaces-and-tabs	Indentation contains mixed spaces and tabs	Rule has been stable since v0.0.229
E111	indentation-with-invalid-multiple	Indentation is not a multiple of {indent_width}	🧪Rule has been in preview since v0.0.269
E112	no-indented-block	Expected an indented block	🧪Rule has been in preview since v0.0.269
E113	unexpected-indentation	Unexpected indentation	🧪Rule has been in preview since v0.0.269
E114	indentation-with-invalid-multiple-comment	Indentation is not a multiple of {indent_width} (comment)	🧪Rule has been in preview since v0.0.269
E115	no-indented-block-comment	Expected an indented block (comment)	🧪Rule has been in preview since v0.0.269
E116	unexpected-indentation-comment	Unexpected indentation (comment)	🧪Rule has been in preview since v0.0.269
E117	over-indented	Over-indented (comment)	🧪Rule has been in preview since v0.0.269
E201	whitespace-after-open-bracket	Whitespace after '{symbol}'	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E202	whitespace-before-close-bracket	Whitespace before '{symbol}'	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E203	whitespace-before-punctuation	Whitespace before '{symbol}'	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E204	whitespace-after-decorator	Whitespace after decorator	🧪Rule has been in preview since 0.5.1🛠️Automatic fix available
E211	whitespace-before-parameters	Whitespace before '{bracket}'	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E221	multiple-spaces-before-operator	Multiple spaces before operator	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E222	multiple-spaces-after-operator	Multiple spaces after operator	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E223	tab-before-operator	Tab before operator	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E224	tab-after-operator	Tab after operator	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E225	missing-whitespace-around-operator	Missing whitespace around operator	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E226	missing-whitespace-around-arithmetic-operator	Missing whitespace around arithmetic operator	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E227	missing-whitespace-around-bitwise-or-shift-operator	Missing whitespace around bitwise or shift operator	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E228	missing-whitespace-around-modulo-operator	Missing whitespace around modulo operator	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E231	missing-whitespace	Missing whitespace after {}	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E241	multiple-spaces-after-comma	Multiple spaces after comma	🧪Rule has been in preview since v0.0.281🛠️Automatic fix available
E242	tab-after-comma	Tab after comma	🧪Rule has been in preview since v0.0.281🛠️Automatic fix available
E251	unexpected-spaces-around-keyword-parameter-equals	Unexpected spaces around keyword / parameter equals	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E252	missing-whitespace-around-parameter-equals	Missing whitespace around parameter equals	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E261	too-few-spaces-before-inline-comment	Insert at least two spaces before an inline comment	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E262	no-space-after-inline-comment	Inline comment should start with #	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E265	no-space-after-block-comment	Block comment should start with #	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E266	multiple-leading-hashes-for-block-comment	Too many leading # before block comment	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E271	multiple-spaces-after-keyword	Multiple spaces after keyword	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E272	multiple-spaces-before-keyword	Multiple spaces before keyword	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E273	tab-after-keyword	Tab after keyword	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E274	tab-before-keyword	Tab before keyword	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E275	missing-whitespace-after-keyword	Missing whitespace after keyword	🧪Rule has been in preview since v0.0.269🛠️Automatic fix available
E301	blank-line-between-methods	Expected {BLANK_LINES_NESTED_LEVEL:?} blank line, found 0	🧪Rule has been in preview since v0.2.2🛠️Automatic fix available
E302	blank-lines-top-level	Expected {expected_blank_lines:?} blank lines, found {actual_blank_lines}	🧪Rule has been in preview since v0.2.2🛠️Automatic fix available
E303	too-many-blank-lines	Too many blank lines ({actual_blank_lines})	🧪Rule has been in preview since v0.2.2🛠️Automatic fix available
E304	blank-line-after-decorator	Blank lines found after function decorator ({lines})	🧪Rule has been in preview since v0.2.2🛠️Automatic fix available
E305	blank-lines-after-function-or-class	Expected 2 blank lines after class or function definition, found ({blank_lines})	🧪Rule has been in preview since v0.2.2🛠️Automatic fix available
E306	blank-lines-before-nested-definition	Expected 1 blank line before a nested definition, found 0	🧪Rule has been in preview since v0.2.2🛠️Automatic fix available
E401	multiple-imports-on-one-line	Multiple imports on one line	Rule has been stable since v0.0.191🛠️Automatic fix available
E402	module-import-not-at-top-of-file	Module level import not at top of cell	Rule has been stable since v0.0.28
E501	line-too-long	Line too long ({width} > {limit})	Rule has been stable since v0.0.18
E502	redundant-backslash	Redundant backslash	🧪Rule has been in preview since v0.3.3🛠️Automatic fix available
E701	multiple-statements-on-one-line-colon	Multiple statements on one line (colon)	Rule has been stable since v0.0.245
E702	multiple-statements-on-one-line-semicolon	Multiple statements on one line (semicolon)	Rule has been stable since v0.0.245
E703	useless-semicolon	Statement ends with an unnecessary semicolon	Rule has been stable since v0.0.245🛠️Automatic fix available
E711	none-comparison	Comparison to None should be cond is None	Rule has been stable since v0.0.28🛠️Automatic fix available
E712	true-false-comparison	Avoid equality comparisons to True; use {cond}: for truth checks	Rule has been stable since v0.0.28🛠️Automatic fix available
E713	not-in-test	Test for membership should be not in	Rule has been stable since v0.0.28🛠️Automatic fix available
E714	not-is-test	Test for object identity should be is not	Rule has been stable since v0.0.28🛠️Automatic fix available
E721	type-comparison	Use is and is not for type comparisons, or isinstance() for isinstance checks	Rule has been stable since v0.0.39
E722	bare-except	Do not use bare except	Rule has been stable since v0.0.36
E731	lambda-assignment	Do not assign a lambda expression, use a def	Rule has been stable since v0.0.28🛠️Automatic fix available
E741	ambiguous-variable-name	Ambiguous variable name: {name}	Rule has been stable since v0.0.34
E742	ambiguous-class-name	Ambiguous class name: {name}	Rule has been stable since v0.0.35
E743	ambiguous-function-name	Ambiguous function name: {name}	Rule has been stable since v0.0.35
E902	io-error	{message}	Rule has been stable since v0.0.28
E999	syntax-error	SyntaxError	❌Rule was removed in 0.8.0

Warning (W)

Code	Name	Message	Fix/Status
W191	tab-indentation	Indentation contains tabs	Rule has been stable since v0.0.254
W291	trailing-whitespace	Trailing whitespace	Rule has been stable since v0.0.253🛠️Automatic fix available
W292	missing-newline-at-end-of-file	No newline at end of file	Rule has been stable since v0.0.61🛠️Automatic fix available
W293	blank-line-with-whitespace	Blank line contains whitespace	Rule has been stable since v0.0.253🛠️Automatic fix available
W391	too-many-newlines-at-end-of-file	Too many newlines at end of {domain}	🧪Rule has been in preview since v0.3.3🛠️Automatic fix available
W505	doc-line-too-long	Doc line too long ({width} > {limit})	Rule has been stable since v0.0.219
W605	invalid-escape-sequence	Invalid escape sequence: \{ch}	Rule has been stable since v0.0.85🛠️Automatic fix available

pydoclint (DOC)

For more, see pydoclint on PyPI.

For related settings, see pydoclint.

Code	Name	Message	Fix/Status
DOC102	docstring-extraneous-parameter	Documented parameter {id} is not in the function's signature	🧪Rule has been in preview since 0.14.1
DOC201	docstring-missing-returns	return is not documented in docstring	🧪Rule has been in preview since 0.5.6
DOC202	docstring-extraneous-returns	Docstring should not have a returns section because the function doesn't return anything	🧪Rule has been in preview since 0.5.6
DOC402	docstring-missing-yields	yield is not documented in docstring	🧪Rule has been in preview since 0.5.7
DOC403	docstring-extraneous-yields	Docstring has a "Yields" section but the function doesn't yield anything	🧪Rule has been in preview since 0.5.7
DOC501	docstring-missing-exception	Raised exception {id} missing from docstring	🧪Rule has been in preview since 0.5.5
DOC502	docstring-extraneous-exception	Raised exception is not explicitly raised: {id}	🧪Rule has been in preview since 0.5.5

pydocstyle (D)

For more, see pydocstyle on PyPI.

For related settings, see pydocstyle.

Code	Name	Message	Fix/Status
D100	undocumented-public-module	Missing docstring in public module	Rule has been stable since v0.0.70
D101	undocumented-public-class	Missing docstring in public class	Rule has been stable since v0.0.70
D102	undocumented-public-method	Missing docstring in public method	Rule has been stable since v0.0.70
D103	undocumented-public-function	Missing docstring in public function	Rule has been stable since v0.0.70
D104	undocumented-public-package	Missing docstring in public package	Rule has been stable since v0.0.70
D105	undocumented-magic-method	Missing docstring in magic method	Rule has been stable since v0.0.70
D106	undocumented-public-nested-class	Missing docstring in public nested class	Rule has been stable since v0.0.70
D107	undocumented-public-init	Missing docstring in __init__	Rule has been stable since v0.0.70
D200	unnecessary-multiline-docstring	One-line docstring should fit on one line	Rule has been stable since v0.0.68🛠️Automatic fix available
D201	blank-line-before-function	No blank lines allowed before function docstring (found {num_lines})	Rule has been stable since v0.0.70🛠️Automatic fix available
D202	blank-line-after-function	No blank lines allowed after function docstring (found {num_lines})	Rule has been stable since v0.0.70🛠️Automatic fix available
D203	incorrect-blank-line-before-class	1 blank line required before class docstring	Rule has been stable since v0.0.70🛠️Automatic fix available
D204	incorrect-blank-line-after-class	1 blank line required after class docstring	Rule has been stable since v0.0.70🛠️Automatic fix available
D205	missing-blank-line-after-summary	1 blank line required between summary line and description	Rule has been stable since v0.0.68🛠️Automatic fix available
D206	docstring-tab-indentation	Docstring should be indented with spaces, not tabs	Rule has been stable since v0.0.75
D207	under-indentation	Docstring is under-indented	Rule has been stable since v0.0.75🛠️Automatic fix available
D208	over-indentation	Docstring is over-indented	Rule has been stable since v0.0.75🛠️Automatic fix available
D209	new-line-after-last-paragraph	Multi-line docstring closing quotes should be on a separate line	Rule has been stable since v0.0.68🛠️Automatic fix available
D210	surrounding-whitespace	No whitespaces allowed surrounding docstring text	Rule has been stable since v0.0.68🛠️Automatic fix available
D211	blank-line-before-class	No blank lines allowed before class docstring	Rule has been stable since v0.0.70🛠️Automatic fix available
D212	multi-line-summary-first-line	Multi-line docstring summary should start at the first line	Rule has been stable since v0.0.69🛠️Automatic fix available
D213	multi-line-summary-second-line	Multi-line docstring summary should start at the second line	Rule has been stable since v0.0.69🛠️Automatic fix available
D214	overindented-section	Section is over-indented ("{name}")	Rule has been stable since v0.0.73🛠️Automatic fix available
D215	overindented-section-underline	Section underline is over-indented ("{name}")	Rule has been stable since v0.0.73🛠️Automatic fix available
D300	triple-single-quotes	Use triple double quotes """	Rule has been stable since v0.0.69🛠️Automatic fix available
D301	escape-sequence-in-docstring	Use r""" if any backslashes in a docstring	Rule has been stable since v0.0.172🛠️Automatic fix available
D400	missing-trailing-period	First line should end with a period	Rule has been stable since v0.0.68🛠️Automatic fix available
D401	non-imperative-mood	First line of docstring should be in imperative mood: "{first_line}"	Rule has been stable since v0.0.228
D402	signature-in-docstring	First line should not be the function's signature	Rule has been stable since v0.0.70
D403	first-word-uncapitalized	First word of the docstring should be capitalized: {} -> {}	Rule has been stable since v0.0.69🛠️Automatic fix available
D404	docstring-starts-with-this	First word of the docstring should not be "This"	Rule has been stable since v0.0.71
D405	non-capitalized-section-name	Section name should be properly capitalized ("{name}")	Rule has been stable since v0.0.71🛠️Automatic fix available
D406	missing-new-line-after-section-name	Section name should end with a newline ("{name}")	Rule has been stable since v0.0.71🛠️Automatic fix available
D407	missing-dashed-underline-after-section	Missing dashed underline after section ("{name}")	Rule has been stable since v0.0.71🛠️Automatic fix available
D408	missing-section-underline-after-name	Section underline should be in the line following the section's name ("{name}")	Rule has been stable since v0.0.71🛠️Automatic fix available
D409	mismatched-section-underline-length	Section underline should match the length of its name ("{name}")	Rule has been stable since v0.0.71🛠️Automatic fix available
D410	no-blank-line-after-section	Missing blank line after section ("{name}")	Rule has been stable since v0.0.71🛠️Automatic fix available
D411	no-blank-line-before-section	Missing blank line before section ("{name}")	Rule has been stable since v0.0.71🛠️Automatic fix available
D412	blank-lines-between-header-and-content	No blank lines allowed between a section header and its content ("{name}")	Rule has been stable since v0.0.71🛠️Automatic fix available
D413	missing-blank-line-after-last-section	Missing blank line after last section ("{name}")	Rule has been stable since v0.0.71🛠️Automatic fix available
D414	empty-docstring-section	Section has no content ("{name}")	Rule has been stable since v0.0.71
D415	missing-terminal-punctuation	First line should end with a period, question mark, or exclamation point	Rule has been stable since v0.0.69🛠️Automatic fix available
D416	missing-section-name-colon	Section name should end with a colon ("{name}")	Rule has been stable since v0.0.74🛠️Automatic fix available
D417	undocumented-param	Missing argument description in the docstring for {definition}: {name}	Rule has been stable since v0.0.73
D418	overload-with-docstring	Function decorated with @overload shouldn't contain a docstring	Rule has been stable since v0.0.71
D419	empty-docstring	Docstring is empty	Rule has been stable since v0.0.68
D420	incorrect-section-order	Section "{current}" appears after section "{previous}" but should be before it	🧪Rule has been in preview since 0.15.3

Pyflakes (F)

For more, see Pyflakes on PyPI.

For related settings, see Pyflakes.

Code	Name	Message	Fix/Status
F401	unused-import	{name} imported but unused; consider using importlib.util.find_spec to test for availability	Rule has been stable since v0.0.18🛠️Automatic fix available
F402	import-shadowed-by-loop-var	Import {name} from {row} shadowed by loop variable	Rule has been stable since v0.0.44
F403	undefined-local-with-import-star	from {name} import * used; unable to detect undefined names	Rule has been stable since v0.0.18
F404	late-future-import	from __future__ imports must occur at the beginning of the file	Rule has been stable since v0.0.34
F405	undefined-local-with-import-star-usage	{name} may be undefined, or defined from star imports	Rule has been stable since v0.0.44
F406	undefined-local-with-nested-import-star-usage	from {name} import * only allowed at module level	Rule has been stable since v0.0.37
F407	future-feature-not-defined	Future feature {name} is not defined	Rule has been stable since v0.0.34
F501	percent-format-invalid-format	%-format string has invalid format string: {message}	Rule has been stable since v0.0.142
F502	percent-format-expected-mapping	%-format string expected mapping but got sequence	Rule has been stable since v0.0.142
F503	percent-format-expected-sequence	%-format string expected sequence but got mapping	Rule has been stable since v0.0.142
F504	percent-format-extra-named-arguments	%-format string has unused named argument(s): {message}	Rule has been stable since v0.0.142🛠️Automatic fix available
F505	percent-format-missing-argument	%-format string is missing argument(s) for placeholder(s): {message}	Rule has been stable since v0.0.142
F506	percent-format-mixed-positional-and-named	%-format string has mixed positional and named placeholders	Rule has been stable since v0.0.142
F507	percent-format-positional-count-mismatch	%-format string has {wanted} placeholder(s) but {got} substitution(s)	Rule has been stable since v0.0.142
F508	percent-format-star-requires-sequence	%-format string * specifier requires sequence	Rule has been stable since v0.0.142
F509	percent-format-unsupported-format-character	%-format string has unsupported format character {char}	Rule has been stable since v0.0.142
F521	string-dot-format-invalid-format	.format call has invalid format string: {message}	Rule has been stable since v0.0.138
F522	string-dot-format-extra-named-arguments	.format call has unused named argument(s): {message}	Rule has been stable since v0.0.139🛠️Automatic fix available
F523	string-dot-format-extra-positional-arguments	.format call has unused arguments at position(s): {message}	Rule has been stable since v0.0.139🛠️Automatic fix available
F524	string-dot-format-missing-arguments	.format call is missing argument(s) for placeholder(s): {message}	Rule has been stable since v0.0.139
F525	string-dot-format-mixing-automatic	.format string mixes automatic and manual numbering	Rule has been stable since v0.0.139
F541	f-string-missing-placeholders	f-string without any placeholders	Rule has been stable since v0.0.18🛠️Automatic fix available
F601	multi-value-repeated-key-literal	Dictionary key literal {name} repeated	Rule has been stable since v0.0.30🛠️Automatic fix available
F602	multi-value-repeated-key-variable	Dictionary key {name} repeated	Rule has been stable since v0.0.30🛠️Automatic fix available
F621	expressions-in-star-assignment	Too many expressions in star-unpacking assignment	Rule has been stable since v0.0.32
F622	multiple-starred-expressions	Two starred expressions in assignment	Rule has been stable since v0.0.32
F631	assert-tuple	Assert test is a non-empty tuple, which is always True	Rule has been stable since v0.0.28
F632	is-literal	Use == to compare constant literals	Rule has been stable since v0.0.39🛠️Automatic fix available
F633	invalid-print-syntax	Use of >> is invalid with print function	Rule has been stable since v0.0.39
F634	if-tuple	If test is a tuple, which is always True	Rule has been stable since v0.0.18
F701	break-outside-loop	break outside loop	Rule has been stable since v0.0.36
F702	continue-outside-loop	continue not properly in loop	Rule has been stable since v0.0.36
F704	yield-outside-function	{keyword} statement outside of a function	Rule has been stable since v0.0.22
F706	return-outside-function	return statement outside of a function/method	Rule has been stable since v0.0.18
F707	default-except-not-last	An except block as not the last exception handler	Rule has been stable since v0.0.28
F722	forward-annotation-syntax-error	Syntax error in forward annotation: {parse_error}	Rule has been stable since v0.0.39
F811	redefined-while-unused	Redefinition of unused {name} from {row}	Rule has been stable since v0.0.171🛠️Automatic fix available
F821	undefined-name	Undefined name {name}. {tip}	Rule has been stable since v0.0.20
F822	undefined-export	Undefined name {name} in __all__	Rule has been stable since v0.0.25
F823	undefined-local	Local variable {name} referenced before assignment	Rule has been stable since v0.0.24
F841	unused-variable	Local variable {name} is assigned to but never used	Rule has been stable since v0.0.22🛠️Automatic fix available
F842	unused-annotation	Local variable {name} is annotated but never used	Rule has been stable since v0.0.172
F901	raise-not-implemented	raise NotImplemented should be raise NotImplementedError	Rule has been stable since v0.0.18🛠️Automatic fix available

pygrep-hooks (PGH)

For more, see pygrep-hooks on GitHub.

Code	Name	Message	Fix/Status
PGH001	eval	No builtin eval() allowed	❌Rule was removed in v0.2.0
PGH002	deprecated-log-warn	warn is deprecated in favor of warning	❌Rule was removed in v0.2.0🛠️Automatic fix available
PGH003	blanket-type-ignore	Use specific rule codes when ignoring type issues	Rule has been stable since v0.0.187
PGH004	blanket-noqa	Use specific rule codes when using noqa	Rule has been stable since v0.0.200🛠️Automatic fix available
PGH005	invalid-mock-access	Mock method should be called: {name}	Rule has been stable since v0.0.266

Pylint (PL)

For more, see Pylint on PyPI.

For related settings, see Pylint.

Convention (PLC)

Code	Name	Message	Fix/Status
PLC0105	type-name-incorrect-variance	{kind} name "{param_name}" does not reflect its {variance}; consider renaming it to "{replacement_name}"	Rule has been stable since v0.0.278
PLC0131	type-bivariance	{kind} cannot be both covariant and contravariant	Rule has been stable since v0.0.278
PLC0132	type-param-name-mismatch	{kind} name {param_name} does not match assigned variable name {var_name}	Rule has been stable since v0.0.277
PLC0205	single-string-slots	Class __slots__ should be a non-string iterable	Rule has been stable since v0.0.276
PLC0206	dict-index-missing-items	Extracting value from dictionary without calling .items()	Rule has been stable since 0.8.0
PLC0207	missing-maxsplit-arg	String is split more times than necessary	Rule has been stable since 0.15.0🛠️Automatic fix available
PLC0208	iteration-over-set	Use a sequence type instead of a set when iterating over values	Rule has been stable since v0.0.271🛠️Automatic fix available
PLC0414	useless-import-alias	Import alias does not rename original package	Rule has been stable since v0.0.156🛠️Automatic fix available
PLC0415	import-outside-top-level	import should be at the top-level of a file	Rule has been stable since 0.12.0
PLC1802	len-test	len({expression}) used as condition without comparison	Rule has been stable since 0.10.0🛠️Automatic fix available
PLC1901	compare-to-empty-string	{existing} can be simplified to {replacement} as an empty string is falsey	🧪Rule has been in preview since v0.0.255
PLC2401	non-ascii-name	{kind} name {name} contains a non-ASCII character	Rule has been stable since 0.5.0
PLC2403	non-ascii-import-name	Module alias {name} contains a non-ASCII character	Rule has been stable since 0.5.0
PLC2701	import-private-name	Private name import {name} from external module {module}	🧪Rule has been in preview since v0.1.14
PLC2801	unnecessary-dunder-call	Unnecessary dunder call to {method}. {replacement}.	🧪Rule has been in preview since v0.1.12🛠️Automatic fix available
PLC3002	unnecessary-direct-lambda-call	Lambda expression called directly. Execute the expression inline instead.	Rule has been stable since v0.0.153

Error (PLE)

Code	Name	Message	Fix/Status
PLE0100	yield-in-init	__init__ method is a generator	Rule has been stable since v0.0.245
PLE0101	return-in-init	Explicit return in __init__	Rule has been stable since v0.0.248
PLE0115	nonlocal-and-global	Name {name} is both nonlocal and global	Rule has been stable since 0.5.0
PLE0116	continue-in-finally	continue not supported inside finally clause	Rule has been stable since v0.0.257
PLE0117	nonlocal-without-binding	Nonlocal name {name} found without binding	Rule has been stable since v0.0.174
PLE0118	load-before-global-declaration	Name {name} is used prior to global declaration on {row}	Rule has been stable since v0.0.174
PLE0237	non-slot-assignment	Attribute {name} is not defined in class's __slots__	Rule has been stable since v0.1.15
PLE0241	duplicate-bases	Duplicate base {base} for class {class}	Rule has been stable since v0.0.269🛠️Automatic fix available
PLE0302	unexpected-special-method-signature	The special method {} expects {}, {} {} given	Rule has been stable since v0.0.263
PLE0303	invalid-length-return-type	__len__ does not return a non-negative integer	Rule has been stable since 0.6.0
PLE0304	invalid-bool-return-type	__bool__ does not return bool	🧪Rule has been in preview since v0.3.3
PLE0305	invalid-index-return-type	__index__ does not return an integer	Rule has been stable since 0.6.0
PLE0307	invalid-str-return-type	__str__ does not return str	Rule has been stable since v0.0.271
PLE0308	invalid-bytes-return-type	__bytes__ does not return bytes	Rule has been stable since 0.6.0
PLE0309	invalid-hash-return-type	__hash__ does not return an integer	Rule has been stable since 0.6.0
PLE0604	invalid-all-object	Invalid object in __all__, must contain only strings	Rule has been stable since v0.0.237
PLE0605	invalid-all-format	Invalid format for __all__, must be tuple or list	Rule has been stable since v0.0.237
PLE0643	potential-index-error	Expression is likely to raise IndexError	Rule has been stable since 0.5.0
PLE0704	misplaced-bare-raise	Bare raise statement is not inside an exception handler	Rule has been stable since 0.5.0
PLE1132	repeated-keyword-argument	Repeated keyword argument: {duplicate_keyword}	Rule has been stable since 0.5.0
PLE1141	dict-iter-missing-items	Unpacking a dictionary in iteration without calling .items()	🧪Rule has been in preview since v0.3.0🛠️Automatic fix available
PLE1142	await-outside-async	await should be used within an async function	Rule has been stable since v0.0.150
PLE1205	logging-too-many-args	Too many arguments for logging format string	Rule has been stable since v0.0.252
PLE1206	logging-too-few-args	Not enough arguments for logging format string	Rule has been stable since v0.0.252
PLE1300	bad-string-format-character	Unsupported format character '{format_char}'	Rule has been stable since v0.0.283
PLE1307	bad-string-format-type	Format type does not match argument type	Rule has been stable since v0.0.245
PLE1310	bad-str-strip-call	String {strip} call contains duplicate characters (did you mean {removal}?)	Rule has been stable since v0.0.242
PLE1507	invalid-envvar-value	Invalid type for initial os.getenv argument; expected str	Rule has been stable since v0.0.255
PLE1519	singledispatch-method	@singledispatch decorator should not be used on methods	Rule has been stable since 0.6.0🛠️Automatic fix available
PLE1520	singledispatchmethod-function	@singledispatchmethod decorator should not be used on non-method functions	Rule has been stable since 0.6.0🛠️Automatic fix available
PLE1700	yield-from-in-async-function	yield from statement in async function; use async for instead	Rule has been stable since v0.0.271
PLE2502	bidirectional-unicode	Contains control characters that can permit obfuscated code	Rule has been stable since v0.0.244
PLE2510	invalid-character-backspace	Invalid unescaped character backspace, use "\b" instead	Rule has been stable since v0.0.257🛠️Automatic fix available
PLE2512	invalid-character-sub	Invalid unescaped character SUB, use "\x1a" instead	Rule has been stable since v0.0.257🛠️Automatic fix available
PLE2513	invalid-character-esc	Invalid unescaped character ESC, use "\x1b" instead	Rule has been stable since v0.0.257🛠️Automatic fix available
PLE2514	invalid-character-nul	Invalid unescaped character NUL, use "\0" instead	Rule has been stable since v0.0.257🛠️Automatic fix available
PLE2515	invalid-character-zero-width-space	Invalid unescaped character zero-width-space, use "\u200B" instead	Rule has been stable since v0.0.257🛠️Automatic fix available
PLE4703	modified-iterating-set	Iterated set {name} is modified within the for loop	🧪Rule has been in preview since v0.3.5🛠️Automatic fix available

Refactor (PLR)

Code	Name	Message	Fix/Status
PLR0124	comparison-with-itself	Name compared with itself, consider replacing {actual}	Rule has been stable since v0.0.273
PLR0133	comparison-of-constant	Two constants compared in a comparison, consider replacing {left_constant} {op} {right_constant}	Rule has been stable since v0.0.221
PLR0202	no-classmethod-decorator	Class method defined without decorator	🧪Rule has been in preview since v0.1.7🛠️Automatic fix available
PLR0203	no-staticmethod-decorator	Static method defined without decorator	🧪Rule has been in preview since v0.1.7🛠️Automatic fix available
PLR0206	property-with-parameters	Cannot have defined parameters for properties	Rule has been stable since v0.0.153
PLR0402	manual-from-import	Use from {module} import {name} in lieu of alias	Rule has been stable since v0.0.155🛠️Automatic fix available
PLR0904	too-many-public-methods	Too many public methods ({methods} > {max_methods})	🧪Rule has been in preview since v0.0.290
PLR0911	too-many-return-statements	Too many return statements ({returns} > {max_returns})	Rule has been stable since v0.0.242
PLR0912	too-many-branches	Too many branches ({branches} > {max_branches})	Rule has been stable since v0.0.242
PLR0913	too-many-arguments	Too many arguments in function definition ({c_args} > {max_args})	Rule has been stable since v0.0.238
PLR0914	too-many-locals	Too many local variables ({current_amount}/{max_amount})	🧪Rule has been in preview since v0.1.9
PLR0915	too-many-statements	Too many statements ({statements} > {max_statements})	Rule has been stable since v0.0.240
PLR0916	too-many-boolean-expressions	Too many Boolean expressions ({expressions} > {max_expressions})	🧪Rule has been in preview since v0.1.1
PLR0917	too-many-positional-arguments	Too many positional arguments ({c_pos}/{max_pos})	🧪Rule has been in preview since v0.1.7
PLR1701	repeated-isinstance-calls	Merge isinstance calls: {expression}	❌Rule was removed in 0.5.0🛠️Automatic fix available
PLR1702	too-many-nested-blocks	Too many nested blocks ({nested_blocks} > {max_nested_blocks})	🧪Rule has been in preview since v0.1.15
PLR1704	redefined-argument-from-local	Redefining argument with the local name {name}	Rule has been stable since 0.5.0
PLR1706	and-or-ternary	Consider using if-else expression	❌Rule was removed in v0.2.0
PLR1708	stop-iteration-return	Explicit raise StopIteration in generator	🧪Rule has been in preview since 0.14.3
PLR1711	useless-return	Useless return statement at end of function	Rule has been stable since v0.0.257🛠️Automatic fix available
PLR1712	swap-with-temporary-variable	Unnecessary temporary variable	🧪Rule has been in preview since 0.15.3🛠️Automatic fix available
PLR1714	repeated-equality-comparison	Consider merging multiple comparisons: {expression}. Use a set if the elements are hashable.	Rule has been stable since v0.0.279🛠️Automatic fix available
PLR1716	boolean-chained-comparison	Contains chained boolean comparison that can be simplified	Rule has been stable since 0.9.0🛠️Automatic fix available
PLR1722	sys-exit-alias	Use sys.exit() instead of {name}	Rule has been stable since v0.0.156🛠️Automatic fix available
PLR1730	if-stmt-min-max	Replace if statement with {replacement}	Rule has been stable since 0.6.0🛠️Automatic fix available
PLR1733	unnecessary-dict-index-lookup	Unnecessary lookup of dictionary value by key	Rule has been stable since 0.12.0🛠️Automatic fix available
PLR1736	unnecessary-list-index-lookup	List index lookup in enumerate() loop	Rule has been stable since 0.5.0🛠️Automatic fix available
PLR2004	magic-value-comparison	Magic value used in comparison, consider replacing {value} with a constant variable	Rule has been stable since v0.0.221
PLR2044	empty-comment	Line with empty comment	Rule has been stable since 0.5.0🛠️Automatic fix available
PLR5501	collapsible-else-if	Use elif instead of else then if, to reduce indentation	Rule has been stable since v0.0.253🛠️Automatic fix available
PLR6104	non-augmented-assignment	Use {operator} to perform an augmented assignment directly	🧪Rule has been in preview since v0.3.7🛠️Automatic fix available
PLR6201	literal-membership	Use a set literal when testing for membership	🧪Rule has been in preview since v0.1.1🛠️Automatic fix available
PLR6301	no-self-use	Method {method_name} could be a function, class method, or static method	🧪Rule has been in preview since v0.0.286

Warning (PLW)

Code	Name	Message	Fix/Status
PLW0108	unnecessary-lambda	Lambda may be unnecessary; consider inlining inner function	Rule has been stable since 0.15.0🛠️Automatic fix available
PLW0120	useless-else-on-loop	else clause on loop without a break statement; remove the else and dedent its contents	Rule has been stable since v0.0.156🛠️Automatic fix available
PLW0127	self-assigning-variable	Self-assignment of variable {name}	Rule has been stable since v0.0.281
PLW0128	redeclared-assigned-name	Redeclared variable {name} in assignment	Rule has been stable since 0.5.0
PLW0129	assert-on-string-literal	Asserting on an empty string literal will never pass	Rule has been stable since v0.0.258
PLW0131	named-expr-without-context	Named expression used without context	Rule has been stable since v0.0.270
PLW0133	useless-exception-statement	Missing raise statement on exception	Rule has been stable since 0.5.0🛠️Automatic fix available
PLW0177	nan-comparison	Comparing against a NaN value; use math.isnan instead	Rule has been stable since 0.12.0
PLW0211	bad-staticmethod-argument	First argument of a static method should not be named {argument_name}	Rule has been stable since 0.6.0
PLW0244	redefined-slots-in-subclass	Slot {slot_name} redefined from base class {base}	🧪Rule has been in preview since 0.9.3
PLW0245	super-without-brackets	super call is missing parentheses	Rule has been stable since 0.5.0🛠️Automatic fix available
PLW0406	import-self	Module {name} imports itself	Rule has been stable since v0.0.265
PLW0602	global-variable-not-assigned	Using global for {name} but no assignment is done	Rule has been stable since v0.0.174
PLW0603	global-statement	Using the global statement to update {name} is discouraged	Rule has been stable since v0.0.253
PLW0604	global-at-module-level	global at module level is redundant	Rule has been stable since 0.5.0
PLW0642	self-or-cls-assignment	Reassigned {} variable in {method_type} method	Rule has been stable since 0.6.0
PLW0711	binary-op-exception	Exception to catch is the result of a binary and operation	Rule has been stable since v0.0.258
PLW1501	bad-open-mode	{mode} is not a valid mode for open	Rule has been stable since 0.5.0
PLW1507	shallow-copy-environ	Shallow copy of os.environ via copy.copy(os.environ)	Rule has been stable since 0.10.0🛠️Automatic fix available
PLW1508	invalid-envvar-default	Invalid type for environment variable default; expected str or None	Rule has been stable since v0.0.255
PLW1509	subprocess-popen-preexec-fn	preexec_fn argument is unsafe when using threads	Rule has been stable since v0.0.281
PLW1510	subprocess-run-without-check	subprocess.run without explicit check argument	Rule has been stable since v0.0.285🛠️Automatic fix available
PLW1514	unspecified-encoding	{function_name} in text mode without explicit encoding argument	🧪Rule has been in preview since v0.1.1🛠️Automatic fix available
PLW1641	eq-without-hash	Object does not implement __hash__ method	Rule has been stable since 0.12.0
PLW2101	useless-with-lock	Threading lock directly created in with statement has no effect	Rule has been stable since 0.5.0
PLW2901	redefined-loop-name	Outer {outer_kind} variable {name} overwritten by inner {inner_kind} target	Rule has been stable since v0.0.252
PLW3201	bad-dunder-method-name	Dunder method {name} has no special meaning in Python 3	🧪Rule has been in preview since v0.0.285
PLW3301	nested-min-max	Nested {func} calls can be flattened	Rule has been stable since v0.0.266🛠️Automatic fix available

pyupgrade (UP)

For more, see pyupgrade on PyPI.

For related settings, see pyupgrade.

Code	Name	Message	Fix/Status
UP001	useless-metaclass-type	__metaclass__ = type is implied	Rule has been stable since v0.0.155🛠️Automatic fix available
UP003	type-of-primitive	Use {} instead of type(...)	Rule has been stable since v0.0.155🛠️Automatic fix available
UP004	useless-object-inheritance	Class {name} inherits from object	Rule has been stable since v0.0.155🛠️Automatic fix available
UP005	deprecated-unittest-alias	{alias} is deprecated, use {target}	Rule has been stable since v0.0.155🛠️Automatic fix available
UP006	non-pep585-annotation	Use {to} instead of {from} for type annotation	Rule has been stable since v0.0.155🛠️Automatic fix available
UP007	non-pep604-annotation-union	Use X | Y for type annotations	Rule has been stable since v0.0.155🛠️Automatic fix available
UP008	super-call-with-parameters	Use super() instead of super(__class__, self)	Rule has been stable since v0.0.155🛠️Automatic fix available
UP009	utf8-encoding-declaration	UTF-8 encoding declaration is unnecessary	Rule has been stable since v0.0.155🛠️Automatic fix available
UP010	unnecessary-future-import	Unnecessary __future__ import {import} for target Python version	Rule has been stable since v0.0.155🛠️Automatic fix available
UP011	lru-cache-without-parameters	Unnecessary parentheses to functools.lru_cache	Rule has been stable since v0.0.155🛠️Automatic fix available
UP012	unnecessary-encode-utf8	Unnecessary call to encode as UTF-8	Rule has been stable since v0.0.155🛠️Automatic fix available
UP013	convert-typed-dict-functional-to-class	Convert {name} from TypedDict functional to class syntax	Rule has been stable since v0.0.155🛠️Automatic fix available
UP014	convert-named-tuple-functional-to-class	Convert {name} from NamedTuple functional to class syntax	Rule has been stable since v0.0.155🛠️Automatic fix available
UP015	redundant-open-modes	Unnecessary mode argument	Rule has been stable since v0.0.155🛠️Automatic fix available
UP017	datetime-timezone-utc	Use datetime.UTC alias	Rule has been stable since v0.0.192🛠️Automatic fix available
UP018	native-literals	Unnecessary {literal_type} call (rewrite as a literal)	Rule has been stable since v0.0.193🛠️Automatic fix available
UP019	typing-text-str-alias	{}.Text is deprecated, use str	Rule has been stable since v0.0.195🛠️Automatic fix available
UP020	open-alias	Use builtin open	Rule has been stable since v0.0.196🛠️Automatic fix available
UP021	replace-universal-newlines	universal_newlines is deprecated, use text	Rule has been stable since v0.0.196🛠️Automatic fix available
UP022	replace-stdout-stderr	Prefer capture_output over sending stdout and stderr to PIPE	Rule has been stable since v0.0.199🛠️Automatic fix available
UP023	deprecated-c-element-tree	cElementTree is deprecated, use ElementTree	Rule has been stable since v0.0.199🛠️Automatic fix available
UP024	os-error-alias	Replace aliased errors with OSError	Rule has been stable since v0.0.206🛠️Automatic fix available
UP025	unicode-kind-prefix	Remove unicode literals from strings	Rule has been stable since v0.0.201🛠️Automatic fix available
UP026	deprecated-mock-import	mock is deprecated, use unittest.mock	Rule has been stable since v0.0.206🛠️Automatic fix available
UP027	unpacked-list-comprehension	Replace unpacked list comprehension with a generator expression	❌Rule was removed in 0.8.0
UP028	yield-in-for-loop	Replace yield over for loop with yield from	Rule has been stable since v0.0.210🛠️Automatic fix available
UP029	unnecessary-builtin-import	Unnecessary builtin import: {import}	Rule has been stable since v0.0.211🛠️Automatic fix available
UP030	format-literals	Use implicit references for positional format fields	Rule has been stable since v0.0.218🛠️Automatic fix available
UP031	printf-string-formatting	Use format specifiers instead of percent format	Rule has been stable since v0.0.229🛠️Automatic fix available
UP032	f-string	Use f-string instead of format call	Rule has been stable since v0.0.224🛠️Automatic fix available
UP033	lru-cache-with-maxsize-none	Use @functools.cache instead of @functools.lru_cache(maxsize=None)	Rule has been stable since v0.0.225🛠️Automatic fix available
UP034	extraneous-parentheses	Avoid extraneous parentheses	Rule has been stable since v0.0.228🛠️Automatic fix available
UP035	deprecated-import	Import from {target} instead: {names}	Rule has been stable since v0.0.239🛠️Automatic fix available
UP036	outdated-version-block	Version block is outdated for minimum Python version	Rule has been stable since v0.0.240🛠️Automatic fix available
UP037	quoted-annotation	Remove quotes from type annotation	Rule has been stable since v0.0.242🛠️Automatic fix available
UP038	non-pep604-isinstance	Use X | Y in {} call instead of (X, Y)	❌Rule was removed in 0.13.0🛠️Automatic fix available
UP039	unnecessary-class-parentheses	Unnecessary parentheses after class definition	Rule has been stable since v0.0.273🛠️Automatic fix available
UP040	non-pep695-type-alias	Type alias {name} uses {type_alias_method} instead of the type keyword	Rule has been stable since v0.0.283🛠️Automatic fix available
UP041	timeout-error-alias	Replace aliased errors with TimeoutError	Rule has been stable since v0.2.0🛠️Automatic fix available
UP042	replace-str-enum	Class {name} inherits from both str and enum.Enum	Rule has been stable since 0.15.0🛠️Automatic fix available
UP043	unnecessary-default-type-args	Unnecessary default type arguments	Rule has been stable since 0.8.0🛠️Automatic fix available
UP044	non-pep646-unpack	Use * for unpacking	Rule has been stable since 0.10.0🛠️Automatic fix available
UP045	non-pep604-annotation-optional	Use X | None for type annotations	Rule has been stable since 0.12.0🛠️Automatic fix available
UP046	non-pep695-generic-class	Generic class {name} uses Generic subclass instead of type parameters	Rule has been stable since 0.12.0🛠️Automatic fix available
UP047	non-pep695-generic-function	Generic function {name} should use type parameters	Rule has been stable since 0.12.0🛠️Automatic fix available
UP049	private-type-parameter	Generic {} uses private type parameters	Rule has been stable since 0.12.0🛠️Automatic fix available
UP050	useless-class-metaclass-type	Class {name} uses metaclass=type, which is redundant	Rule has been stable since 0.13.0🛠️Automatic fix available

refurb (FURB)

For more, see refurb on PyPI.

Code	Name	Message	Fix/Status
FURB101	read-whole-file	Path.open() followed by read() can be replaced by {filename}.{suggestion}	🧪Rule has been in preview since v0.1.2🛠️Automatic fix available
FURB103	write-whole-file	Path.open() followed by write() can be replaced by {filename}.{suggestion}	🧪Rule has been in preview since v0.3.6🛠️Automatic fix available
FURB105	print-empty-string	Unnecessary empty string passed to print	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB110	if-exp-instead-of-or-operator	Replace ternary if expression with or operator	Rule has been stable since 0.15.0🛠️Automatic fix available
FURB113	repeated-append	Use {suggestion} instead of repeatedly calling {name}.append()	🧪Rule has been in preview since v0.0.287🛠️Automatic fix available
FURB116	f-string-number-format	Replace {function_name} call with {display}	Rule has been stable since 0.13.0🛠️Automatic fix available
FURB118	reimplemented-operator	Use operator.{operator} instead of defining a {target}	🧪Rule has been in preview since v0.1.9🛠️Automatic fix available
FURB122	for-loop-writes	Use of {}.write in a for loop	Rule has been stable since 0.12.0🛠️Automatic fix available
FURB129	readlines-in-for	Instead of calling readlines(), iterate over file object directly	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB131	delete-full-slice	Prefer clear over deleting a full slice	🧪Rule has been in preview since v0.0.287🛠️Automatic fix available
FURB132	check-and-remove-from-set	Use {suggestion} instead of check and remove	Rule has been stable since 0.12.0🛠️Automatic fix available
FURB136	if-expr-min-max	Replace if expression with {min_max} call	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB140	reimplemented-starmap	Use itertools.starmap instead of the generator	🧪Rule has been in preview since v0.0.291🛠️Automatic fix available
FURB142	for-loop-set-mutations	Use of set.{}() in a for loop	🧪Rule has been in preview since v0.3.5🛠️Automatic fix available
FURB145	slice-copy	Prefer copy method over slicing	🧪Rule has been in preview since v0.0.290🛠️Automatic fix available
FURB148	unnecessary-enumerate	enumerate value is unused, use for x in range(len(y)) instead	🧪Rule has been in preview since v0.0.291🛠️Automatic fix available
FURB152	math-constant	Replace {literal} with math.{constant}	🧪Rule has been in preview since v0.1.6🛠️Automatic fix available
FURB154	repeated-global	Use of repeated consecutive {}	🧪Rule has been in preview since v0.4.9🛠️Automatic fix available
FURB156	hardcoded-string-charset	Use of hardcoded string charset	🧪Rule has been in preview since 0.7.0🛠️Automatic fix available
FURB157	verbose-decimal-constructor	Verbose expression in Decimal constructor	Rule has been stable since 0.12.0🛠️Automatic fix available
FURB161	bit-count	Use of bin({existing}).count('1')	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB162	fromisoformat-replace-z	Unnecessary timezone replacement with zero offset	Rule has been stable since 0.12.0🛠️Automatic fix available
FURB163	redundant-log-base	Prefer math.{log_function}({arg}) over math.log with a redundant base	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB164	unnecessary-from-float	Verbose method {method_name} in {constructor} construction	🧪Rule has been in preview since v0.3.5🛠️Automatic fix available
FURB166	int-on-sliced-str	Use of int with explicit base={base} after removing prefix	Rule has been stable since 0.12.0🛠️Automatic fix available
FURB167	regex-flag-alias	Use of regular expression alias re.{}	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB168	isinstance-type-none	Prefer is operator over isinstance to check if an object is None	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB169	type-none-comparison	When checking against None, use {} instead of comparison with type(None)	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB171	single-item-membership-test	Membership test against single-item container	Rule has been stable since 0.15.0🛠️Automatic fix available
FURB177	implicit-cwd	Prefer Path.cwd() over Path().resolve() for current-directory lookups	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB180	meta-class-abc-meta	Use of metaclass=abc.ABCMeta to define abstract base class	🧪Rule has been in preview since v0.2.0🛠️Automatic fix available
FURB181	hashlib-digest-hex	Use of hashlib's .digest().hex()	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB187	list-reverse-copy	Use of assignment of reversed on list {name}	Rule has been stable since 0.5.0🛠️Automatic fix available
FURB188	slice-to-remove-prefix-or-suffix	Prefer str.removeprefix() over conditionally replacing with slice.	Rule has been stable since 0.9.0🛠️Automatic fix available
FURB189	subclass-builtin	Subclassing {subclass} can be error prone, use collections.{replacement} instead	🧪Rule has been in preview since 0.7.3🛠️Automatic fix available
FURB192	sorted-min-max	Prefer min over sorted() to compute the minimum value in a sequence	🧪Rule has been in preview since v0.4.2🛠️Automatic fix available

Ruff-specific rules (RUF)

For related settings, see Ruff.

Code	Name	Message	Fix/Status
RUF001	ambiguous-unicode-character-string	String contains ambiguous {}. Did you mean {}?	Rule has been stable since v0.0.102
RUF002	ambiguous-unicode-character-docstring	Docstring contains ambiguous {}. Did you mean {}?	Rule has been stable since v0.0.102
RUF003	ambiguous-unicode-character-comment	Comment contains ambiguous {}. Did you mean {}?	Rule has been stable since v0.0.108
RUF005	collection-literal-concatenation	Consider {expression} instead of concatenation	Rule has been stable since v0.0.227🛠️Automatic fix available
RUF006	asyncio-dangling-task	Store a reference to the return value of {expr}.{method}	Rule has been stable since v0.0.247
RUF007	zip-instead-of-pairwise	Prefer itertools.pairwise() over zip() when iterating over successive pairs	Rule has been stable since v0.0.257🛠️Automatic fix available
RUF008	mutable-dataclass-default	Do not use mutable default values for dataclass attributes	Rule has been stable since v0.0.262
RUF009	function-call-in-dataclass-default-argument	Do not perform function call {name} in dataclass defaults	Rule has been stable since v0.0.262
RUF010	explicit-f-string-type-conversion	Use explicit conversion flag	Rule has been stable since v0.0.267🛠️Automatic fix available
RUF011	ruff-static-key-dict-comprehension	Dictionary comprehension uses static key	❌Rule was removed in v0.2.0
RUF012	mutable-class-default	Mutable default value for class attribute	Rule has been stable since v0.0.273
RUF013	implicit-optional	PEP 484 prohibits implicit Optional	Rule has been stable since v0.0.273🛠️Automatic fix available
RUF015	unnecessary-iterable-allocation-for-first-element	Prefer next({iterable}) over single element slice	Rule has been stable since v0.0.278🛠️Automatic fix available
RUF016	invalid-index-type	Slice in indexed access to type {value_type} uses type {index_type} instead of an integer	Rule has been stable since v0.0.278
RUF017	quadratic-list-summation	Avoid quadratic list summation	Rule has been stable since v0.0.285🛠️Automatic fix available
RUF018	assignment-in-assert	Avoid assignment expressions in assert statements	Rule has been stable since v0.2.0
RUF019	unnecessary-key-check	Unnecessary key check before dictionary access	Rule has been stable since v0.2.0🛠️Automatic fix available
RUF020	never-union	{never_like} | T is equivalent to T	Rule has been stable since v0.2.0🛠️Automatic fix available
RUF021	parenthesize-chained-operators	Parenthesize a and b expressions when chaining and and or together, to make the precedence clear	Rule has been stable since 0.8.0🛠️Automatic fix available
RUF022	unsorted-dunder-all	__all__ is not sorted	Rule has been stable since 0.8.0🛠️Automatic fix available
RUF023	unsorted-dunder-slots	{}.__slots__ is not sorted	Rule has been stable since 0.8.0🛠️Automatic fix available
RUF024	mutable-fromkeys-value	Do not pass mutable objects as values to dict.fromkeys	Rule has been stable since 0.5.0🛠️Automatic fix available
RUF026	default-factory-kwarg	default_factory is a positional-only argument to defaultdict	Rule has been stable since 0.5.0🛠️Automatic fix available
RUF027	missing-f-string-syntax	Possible f-string without an f prefix	🧪Rule has been in preview since v0.2.1🛠️Automatic fix available
RUF028	invalid-formatter-suppression-comment	This suppression comment is invalid because {}	Rule has been stable since 0.12.0🛠️Automatic fix available
RUF029	unused-async	Function {name} is declared async, but doesn't await or use async features.	🧪Rule has been in preview since v0.4.0
RUF030	assert-with-print-message	print() call in assert statement is likely unintentional	Rule has been stable since 0.8.0🛠️Automatic fix available
RUF031	incorrectly-parenthesized-tuple-in-subscript	Use parentheses for tuples in subscripts	🧪Rule has been in preview since 0.5.7🛠️Automatic fix available
RUF032	decimal-from-float-literal	Decimal() called with float literal argument	Rule has been stable since 0.9.0🛠️Automatic fix available
RUF033	post-init-default	__post_init__ method with argument defaults	Rule has been stable since 0.9.0🛠️Automatic fix available
RUF034	useless-if-else	Useless if-else condition	Rule has been stable since 0.9.0
RUF035	ruff-unsafe-markup-use	Unsafe use of {name} detected	❌Rule was removed in 0.10.0
RUF036	none-not-at-end-of-union	None not at the end of the type union.	🧪Rule has been in preview since 0.7.4🛠️Automatic fix available
RUF037	unnecessary-empty-iterable-within-deque-call	Unnecessary empty iterable within a deque call	Rule has been stable since 0.15.0🛠️Automatic fix available
RUF038	redundant-bool-literal	Literal[True, False, ...] can be replaced with Literal[...] | bool	🧪Rule has been in preview since 0.8.0🛠️Automatic fix available
RUF039	unraw-re-pattern	First argument to {call} is not raw string	🧪Rule has been in preview since 0.8.0🛠️Automatic fix available
RUF040	invalid-assert-message-literal-argument	Non-string literal used as assert message	Rule has been stable since 0.10.0
RUF041	unnecessary-nested-literal	Unnecessary nested Literal	Rule has been stable since 0.10.0🛠️Automatic fix available
RUF043	pytest-raises-ambiguous-pattern	Pattern passed to match= contains metacharacters but is neither escaped nor raw	Rule has been stable since 0.13.0
RUF045	implicit-class-var-in-dataclass	Assignment without annotation found in dataclass body	🧪Rule has been in preview since 0.9.7
RUF046	unnecessary-cast-to-int	Value being cast to int is already an integer	Rule has been stable since 0.10.0🛠️Automatic fix available
RUF047	needless-else	Empty else clause	🧪Rule has been in preview since 0.9.3🛠️Automatic fix available
RUF048	map-int-version-parsing	__version__ may contain non-integral-like elements	Rule has been stable since 0.10.0
RUF049	dataclass-enum	An enum class should not be decorated with @dataclass	Rule has been stable since 0.12.0
RUF050	unnecessary-if	Empty if statement	🧪Rule has been in preview since 0.15.8🛠️Automatic fix available
RUF051	if-key-in-dict-del	Use pop instead of key in dict followed by del dict[key]	Rule has been stable since 0.10.0🛠️Automatic fix available
RUF052	used-dummy-variable	Local dummy variable {} is accessed	🧪Rule has been in preview since 0.8.2🛠️Automatic fix available
RUF053	class-with-mixed-type-vars	Class with type parameter list inherits from Generic	Rule has been stable since 0.12.0🛠️Automatic fix available
RUF054	indented-form-feed	Indented form feed	🧪Rule has been in preview since 0.9.6
RUF055	unnecessary-regular-expression	Plain string pattern passed to re function	🧪Rule has been in preview since 0.8.1🛠️Automatic fix available
RUF056	falsy-dict-get-fallback	Avoid providing a falsy fallback to dict.get() in boolean test positions. The default fallback None is already falsy.	🧪Rule has been in preview since 0.8.5🛠️Automatic fix available
RUF057	unnecessary-round	Value being rounded is already an integer	Rule has been stable since 0.12.0🛠️Automatic fix available
RUF058	starmap-zip	itertools.starmap called on zip iterable	Rule has been stable since 0.12.0🛠️Automatic fix available
RUF059	unused-unpacked-variable	Unpacked variable {name} is never used	Rule has been stable since 0.13.0🛠️Automatic fix available
RUF060	in-empty-collection	Unnecessary membership test on empty collection	Rule has been stable since 0.15.0
RUF061	legacy-form-pytest-raises	Use context-manager form of pytest.{}()	Rule has been stable since 0.15.0🛠️Automatic fix available
RUF063	access-annotations-from-class-dict	Use {suggestion} instead of __dict__ access	🧪Rule has been in preview since 0.12.1
RUF064	non-octal-permissions	Non-octal mode	Rule has been stable since 0.15.0🛠️Automatic fix available
RUF065	logging-eager-conversion	Unnecessary oct() conversion when formatting with %s. Use %#o instead of %s	🧪Rule has been in preview since 0.13.2
RUF066	property-without-return	{name} is a property without a return statement	🧪Rule has been in preview since 0.14.7
RUF067	non-empty-init-module	__init__ module should not contain any code	🧪Rule has been in preview since 0.14.11
RUF068	duplicate-entry-in-dunder-all	__all__ contains duplicate entries	🧪Rule has been in preview since 0.14.14🛠️Automatic fix available
RUF069	float-equality-comparison	Unreliable floating point equality comparison {left} {operator} {right}	🧪Rule has been in preview since 0.15.1
RUF070	unnecessary-assign-before-yield	Unnecessary assignment to {name} before yield from statement	🧪Rule has been in preview since 0.15.3🛠️Automatic fix available
RUF071	os-path-commonprefix	os.path.commonprefix() compares strings character-by-character	🧪Rule has been in preview since 0.15.6🛠️Automatic fix available
RUF072	useless-finally	Empty finally clause	🧪Rule has been in preview since 0.15.8🛠️Automatic fix available
RUF073	f-string-percent-format	% operator used on an f-string	🧪Rule has been in preview since 0.15.8
RUF100	unused-noqa	Unused {}	Rule has been stable since v0.0.155🛠️Automatic fix available
RUF101	redirected-noqa	{original} is a redirect to {target}	Rule has been stable since 0.6.0🛠️Automatic fix available
RUF102	invalid-rule-code	Invalid rule code in {}: {}	Rule has been stable since 0.15.0🛠️Automatic fix available
RUF103	invalid-suppression-comment	Invalid suppression comment: {msg}	Rule has been stable since 0.15.0🛠️Automatic fix available
RUF104	unmatched-suppression-comment	Suppression comment without matching #ruff:enable comment	Rule has been stable since 0.15.0
RUF200	invalid-pyproject-toml	Failed to parse pyproject.toml: {message}	Rule has been stable since v0.0.271

tryceratops (TRY)

For more, see tryceratops on PyPI.

Code	Name	Message	Fix/Status
TRY002	raise-vanilla-class	Create your own exception	Rule has been stable since v0.0.236
TRY003	raise-vanilla-args	Avoid specifying long messages outside the exception class	Rule has been stable since v0.0.236
TRY004	type-check-without-type-error	Prefer TypeError exception for invalid type	Rule has been stable since v0.0.230
TRY200	reraise-no-cause	Use raise from to specify exception cause	❌Rule was removed in v0.2.0
TRY201	verbose-raise	Use raise without specifying exception name	Rule has been stable since v0.0.231🛠️Automatic fix available
TRY203	useless-try-except	Remove exception handler; error is immediately re-raised	Rule has been stable since 0.7.0
TRY300	try-consider-else	Consider moving this statement to an else block	Rule has been stable since v0.0.229
TRY301	raise-within-try	Abstract raise to an inner function	Rule has been stable since v0.0.233
TRY400	error-instead-of-exception	Use logging.exception instead of logging.error	Rule has been stable since v0.0.236🛠️Automatic fix available
TRY401	verbose-log-message	Redundant exception object included in logging.exception call	Rule has been stable since v0.0.250