Bump version to 0.0.121

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/charliermarsh/ruff-pre-commit
-    rev: v0.0.117
+    rev: v0.0.121
     hooks:
       - id: ruff
 

Cargo.lock

@@ -930,11 +930,12 @@ checksum = "0ce7134b9999ecaf8bcd65542e436736ef32ddca1b3e06094cb6ec5755203b80"
 
 [[package]]
 name = "flake8-to-ruff"
-version = "0.0.117-dev.0"
+version = "0.0.121-dev.0"
 dependencies = [
  "anyhow",
  "clap 4.0.22",
  "configparser",
+ "fnv",
  "once_cell",
  "regex",
  "ruff",
@@ -2237,10 +2238,11 @@ dependencies = [
 
 [[package]]
 name = "ruff"
-version = "0.0.117"
+version = "0.0.121"
 dependencies = [
  "anyhow",
  "assert_cmd",
+ "atty",
  "bincode",
  "bitflags",
  "cacache",
@@ -2285,7 +2287,7 @@ dependencies = [
 
 [[package]]
 name = "ruff_dev"
-version = "0.0.117"
+version = "0.0.121"
 dependencies = [
  "anyhow",
  "clap 4.0.22",

Cargo.toml

@@ -6,7 +6,7 @@ members = [
 
 [package]
 name = "ruff"
-version = "0.0.117"
+version = "0.0.121"
 edition = "2021"
 
 [lib]
@@ -14,6 +14,7 @@ name = "ruff"
 
 [dependencies]
 anyhow = { version = "1.0.66" }
+atty = { version = "0.2.14" }
 bincode = { version = "1.3.3" }
 bitflags = { version = "1.3.2" }
 chrono = { version = "0.4.21", default-features = false, features = ["clock"] }

README.md

@@ -36,8 +36,8 @@ faster than any individual tool.
 automatically convert your existing configuration.)
 
 Ruff is actively developed and used in major open-source projects
-like [Zulip](https://github.com/zulip/zulip), [pydantic](https://github.com/pydantic/pydantic),
-and [Saleor](https://github.com/saleor/saleor).
+like [FastAPI](https://github.com/tiangolo/fastapi), [Zulip](https://github.com/zulip/zulip),
+[pydantic](https://github.com/pydantic/pydantic), and [Saleor](https://github.com/saleor/saleor).
 
 Read the [launch blog post](https://notes.crmarsh.com/python-tooling-could-be-much-much-faster).
 
@@ -48,18 +48,20 @@ Read the [launch blog post](https://notes.crmarsh.com/python-tooling-could-be-mu
 3. [Supported Rules](#supported-rules)
    1. [Pyflakes](#pyflakes)
    2. [pycodestyle](#pycodestyle)
-   3. [pydocstyle](#pydocstyle)
-   4. [pyupgrade](#pyupgrade)
-   5. [pep8-naming](#pep8-naming)
-   6. [flake8-comprehensions](#flake8-comprehensions)
-   7. [flake8-bugbear](#flake8-bugbear)
-   8. [flake8-builtins](#flake8-builtins)
-   9. [flake8-print](#flake8-print)
-   10. [flake8-quotes](#flake8-quotes)
-   11. [flake8-annotations](#flake8-annotations)
-   12. [flake8-2020](#flake8-2020)
-   13. [Ruff-specific rules](#ruff-specific-rules)
-   14. [Meta rules](#meta-rules)
+   3. [isort](#isort)
+   4. [pydocstyle](#pydocstyle)
+   5. [pyupgrade](#pyupgrade)
+   6. [pep8-naming](#pep8-naming)
+   7. [flake8-bandit](#flake8-bandit)
+   8. [flake8-comprehensions](#flake8-comprehensions)
+   9. [flake8-bugbear](#flake8-bugbear)
+   10. [flake8-builtins](#flake8-builtins)
+   11. [flake8-print](#flake8-print)
+   12. [flake8-quotes](#flake8-quotes)
+   13. [flake8-annotations](#flake8-annotations)
+   14. [flake8-2020](#flake8-2020)
+   15. [Ruff-specific rules](#ruff-specific-rules)
+   16. [Meta rules](#meta-rules)
 5. [Editor Integrations](#editor-integrations)
 6. [FAQ](#faq)
 7. [Development](#development)
@@ -235,6 +237,8 @@ Options:
           Regular expression matching the name of dummy variables
       --target-version <TARGET_VERSION>
           The minimum Python version that should be supported
+      --line-length <LINE_LENGTH>
+          Set the line-length for length-associated checks and automatic formatting
       --stdin-filename <STDIN_FILENAME>
           The name of the file when passing it through stdin
   -h, --help
@@ -527,9 +531,13 @@ For more, see [flake8-bugbear](https://pypi.org/project/flake8-bugbear/22.10.27/
 | B017 | NoAssertRaisesException | `assertRaises(Exception)` should be considered evil |  |
 | B018 | UselessExpression | Found useless expression. Either assign it to a variable or remove it. |  |
 | B019 | CachedInstanceMethod | Use of `functools.lru_cache` or `functools.cache` on methods can lead to memory leaks |  |
+| B020 | LoopVariableOverridesIterator | Loop control variable `...` overrides iterable it iterates |  |
 | B021 | FStringDocstring | f-string used as docstring. This will be interpreted by python as a joined string rather than a docstring. |  |
+| B022 | UselessContextlibSuppress | No arguments passed to `contextlib.suppress`. No exceptions will be suppressed and therefore this context manager is redundant |  |
+| B024 | AbstractBaseClassWithoutAbstractMethod | `...` is an abstract base class, but it has no abstract methods |  |
 | B025 | DuplicateTryBlockException | try-except block with duplicate exception `Exception` |  |
 | B026 | StarArgUnpackingAfterKeywordArg | Star-arg unpacking after a keyword argument is strongly discouraged |  |
+| B027 | EmptyMethodWithoutAbstractDecorator | `...` is an empty method in an abstract base class, but has no abstract decorator |  |
 
 ### flake8-builtins
 
@@ -702,7 +710,7 @@ including:
 - [`flake8-annotations`](https://pypi.org/project/flake8-annotations/)
 - [`flake8-comprehensions`](https://pypi.org/project/flake8-comprehensions/)
 - [`flake8-bandit`](https://pypi.org/project/flake8-bandit/) (6/40)
-- [`flake8-bugbear`](https://pypi.org/project/flake8-bugbear/) (22/32)
+- [`flake8-bugbear`](https://pypi.org/project/flake8-bugbear/) (25/32)
 - [`flake8-2020`](https://pypi.org/project/flake8-2020/)
 - [`pyupgrade`](https://pypi.org/project/pyupgrade/) (15/34)
 - [`autoflake`](https://pypi.org/project/autoflake/) (1/7)
@@ -727,7 +735,7 @@ Today, Ruff can be used to replace Flake8 when used with any of the following pl
 - [`flake8-annotations`](https://pypi.org/project/flake8-annotations/)
 - [`flake8-bandit`](https://pypi.org/project/flake8-bandit/) (6/40)
 - [`flake8-comprehensions`](https://pypi.org/project/flake8-comprehensions/)
-- [`flake8-bugbear`](https://pypi.org/project/flake8-bugbear/) (22/32)
+- [`flake8-bugbear`](https://pypi.org/project/flake8-bugbear/) (26/32)
 - [`flake8-2020`](https://pypi.org/project/flake8-2020/)
 
 Ruff can also replace [`isort`](https://pypi.org/project/isort/), [`yesqa`](https://github.com/asottile/yesqa),
@@ -753,9 +761,8 @@ project. See [#283](https://github.com/charliermarsh/ruff/issues/283) for more.
 
 ### How does Ruff's import sorting compare to [`isort`](https://pypi.org/project/isort/)?
 
-Ruff's import sorting is intended to be equivalent to `isort` when used `profile = "black"`, and a
-few other settings (`combine_as_imports = true`, `order_by_type = false`, and
-`case_sensitive = true`).
+Ruff's import sorting is intended to be nearly equivalent to `isort` when used `profile = "black"`.
+(There are some minor differences in how Ruff and isort break ties between similar imports.)
 
 Like `isort`, Ruff's import sorting is compatible with Black.
 

flake8_to_ruff/Cargo.lock

@@ -771,7 +771,7 @@ checksum = "0ce7134b9999ecaf8bcd65542e436736ef32ddca1b3e06094cb6ec5755203b80"
 
 [[package]]
 name = "flake8_to_ruff"
-version = "0.0.117"
+version = "0.0.121"
 dependencies = [
  "anyhow",
  "clap",
@@ -1975,7 +1975,7 @@ dependencies = [
 
 [[package]]
 name = "ruff"
-version = "0.0.117"
+version = "0.0.121"
 dependencies = [
  "anyhow",
  "bincode",

flake8_to_ruff/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "flake8-to-ruff"
-version = "0.0.117-dev.0"
+version = "0.0.121-dev.0"
 edition = "2021"
 
 [lib]
@@ -10,6 +10,7 @@ name = "flake8_to_ruff"
 anyhow = { version = "1.0.66" }
 clap = { version = "4.0.1", features = ["derive"] }
 configparser = { version = "3.0.2" }
+fnv = { version = "1.0.7" }
 once_cell = { version = "1.16.0" }
 regex = { version = "1.6.0" }
 ruff = { path = "..", default-features = false }

flake8_to_ruff/src/parser.rs

@@ -1,7 +1,7 @@
-use std::collections::BTreeMap;
 use std::str::FromStr;
 
 use anyhow::Result;
+use fnv::FnvHashMap;
 use once_cell::sync::Lazy;
 use regex::Regex;
 use ruff::checks_gen::CheckCodePrefix;
@@ -179,8 +179,8 @@ pub fn parse_files_to_codes_mapping(value: &str) -> Result<Vec<PatternPrefixPair
 /// Collect a list of `PatternPrefixPair` structs as a `BTreeMap`.
 pub fn collect_per_file_ignores(
     pairs: Vec<PatternPrefixPair>,
-) -> BTreeMap<String, Vec<CheckCodePrefix>> {
-    let mut per_file_ignores: BTreeMap<String, Vec<CheckCodePrefix>> = BTreeMap::new();
+) -> FnvHashMap<String, Vec<CheckCodePrefix>> {
+    let mut per_file_ignores: FnvHashMap<String, Vec<CheckCodePrefix>> = FnvHashMap::default();
     for pair in pairs {
         per_file_ignores
             .entry(pair.pattern)

resources/test/fixtures/B020.py

@@ -0,0 +1,40 @@
+"""
+Should emit:
+B020 - on lines 8, 21, and 36
+"""
+
+items = [1, 2, 3]
+
+for items in items:
+    print(items)
+
+items = [1, 2, 3]
+
+for item in items:
+    print(item)
+
+values = {"secret": 123}
+
+for key, value in values.items():
+    print(f"{key}, {value}")
+
+for key, values in values.items():
+    print(f"{key}, {values}")
+
+# Variables defined in a comprehension are local in scope
+# to that comprehension and are therefore allowed.
+for var in [var for var in range(10)]:
+    print(var)
+
+for var in (var for var in range(10)):
+    print(var)
+
+for k, v in {k: v for k, v in zip(range(10), range(10, 20))}.items():
+    print(k, v)
+
+# However we still call out reassigning the iterable in the comprehension.
+for vars in [i for i in vars]:
+    print(vars)
+
+for var in sorted(range(10), key=lambda var: var.real):
+    print(var)

resources/test/fixtures/B022.py

@@ -0,0 +1,23 @@
+"""
+Should emit:
+B022 - on lines 8
+"""
+
+import contextlib
+from contextlib import suppress
+
+with contextlib.suppress():
+    raise ValueError
+
+with suppress():
+    raise ValueError
+
+with contextlib.suppress(ValueError):
+    raise ValueError
+
+exceptions_to_suppress = []
+if True:
+    exceptions_to_suppress.append(ValueError)
+
+with contextlib.suppress(*exceptions_to_suppress):
+    raise

resources/test/fixtures/B024.py

@@ -0,0 +1,129 @@
+"""
+Should emit:
+B024 - on lines 17, 34, 52, 58, 69, 74, 79, 84, 89
+"""
+
+import abc
+import abc as notabc
+from abc import ABC, ABCMeta
+from abc import abstractmethod
+from abc import abstractmethod as abstract
+from abc import abstractmethod as abstractaoeuaoeuaoeu
+from abc import abstractmethod as notabstract
+
+import foo
+
+
+class Base_1(ABC):  # error
+    def method(self):
+        foo()
+
+
+class Base_2(ABC):
+    @abstractmethod
+    def method(self):
+        foo()
+
+
+class Base_3(ABC):
+    @abc.abstractmethod
+    def method(self):
+        foo()
+
+
+class Base_4(ABC):
+    @notabc.abstractmethod
+    def method(self):
+        foo()
+
+
+class Base_5(ABC):
+    @abstract
+    def method(self):
+        foo()
+
+
+class Base_6(ABC):
+    @abstractaoeuaoeuaoeu
+    def method(self):
+        foo()
+
+
+class Base_7(ABC):  # error
+    @notabstract
+    def method(self):
+        foo()
+
+
+class MetaBase_1(metaclass=ABCMeta):  # error
+    def method(self):
+        foo()
+
+
+class MetaBase_2(metaclass=ABCMeta):
+    @abstractmethod
+    def method(self):
+        foo()
+
+
+class abc_Base_1(abc.ABC):  # error
+    def method(self):
+        foo()
+
+
+class abc_Base_2(metaclass=abc.ABCMeta):  # error
+    def method(self):
+        foo()
+
+
+class notabc_Base_1(notabc.ABC):  # error
+    def method(self):
+        foo()
+
+
+class multi_super_1(notabc.ABC, abc.ABCMeta):  # safe
+    def method(self):
+        foo()
+
+
+class multi_super_2(notabc.ABC, metaclass=abc.ABCMeta):  # safe
+    def method(self):
+        foo()
+
+
+class non_keyword_abcmeta_1(ABCMeta):  # safe
+    def method(self):
+        foo()
+
+
+class non_keyword_abcmeta_2(abc.ABCMeta):  # safe
+    def method(self):
+        foo()
+
+
+# very invalid code, but that's up to mypy et al to check
+class keyword_abc_1(metaclass=ABC):  # safe
+    def method(self):
+        foo()
+
+
+class keyword_abc_2(metaclass=abc.ABC):  # safe
+    def method(self):
+        foo()
+
+
+class abc_set_class_variable_1(ABC):  # safe
+    foo: int
+
+
+class abc_set_class_variable_2(ABC):  # safe
+    foo = 2
+
+
+class abc_set_class_variable_3(ABC):  # safe
+    foo: int = 2
+
+
+# this doesn't actually declare a class variable, it's just an expression
+class abc_set_class_variable_4(ABC):  # error
+    foo

resources/test/fixtures/B027.py

@@ -0,0 +1,88 @@
+"""
+Should emit:
+B027 - on lines 12, 15, 18, 22, 30
+"""
+import abc
+from abc import ABC
+from abc import abstractmethod
+from abc import abstractmethod as notabstract
+
+
+class AbstractClass(ABC):
+    def empty_1(self):  # error
+        ...
+
+    def empty_2(self):  # error
+        pass
+
+    def empty_3(self):  # error
+        """docstring"""
+        ...
+
+    def empty_4(self):  # error
+        """multiple ellipsis/pass"""
+        ...
+        pass
+        ...
+        pass
+
+    @notabstract
+    def abstract_0(self):
+        ...
+
+    @abstractmethod
+    def abstract_1(self):
+        ...
+
+    @abstractmethod
+    def abstract_2(self):
+        pass
+
+    @abc.abstractmethod
+    def abstract_3(self):
+        ...
+
+    def body_1(self):
+        print("foo")
+        ...
+
+    def body_2(self):
+        self.body_1()
+
+
+class NonAbstractClass:
+    def empty_1(self):  # safe
+        ...
+
+    def empty_2(self):  # safe
+        pass
+
+
+# ignore @overload, fixes issue #304
+# ignore overload with other imports, fixes #308
+import typing
+import typing as t
+import typing as anything
+from typing import Union, overload
+
+
+class AbstractClass(ABC):
+    @overload
+    def empty_1(self, foo: str):
+        ...
+
+    @typing.overload
+    def empty_1(self, foo: int):
+        ...
+
+    @t.overload
+    def empty_1(self, foo: list):
+        ...
+
+    @anything.overload
+    def empty_1(self, foo: float):
+        ...
+
+    @abstractmethod
+    def empty_1(self, foo: Union[str, int, list, float]):
+        ...

resources/test/fixtures/F401_6.py

@@ -8,3 +8,13 @@ from .background import BackgroundTasks
 
 # F401 `datastructures.UploadFile` imported but unused
 from .datastructures import UploadFile as FileUpload
+
+
+# OK
+import applications as applications
+
+# F401 `background` imported but unused
+import background
+
+# F401 `datastructures` imported but unused
+import datastructures as structures

resources/test/fixtures/F821_4.py

@@ -0,0 +1,24 @@
+"""Test: import alias tracking."""
+from typing import List
+
+_ = List["Model"]
+
+
+from typing import List as IList
+
+_ = IList["Model"]
+
+
+from collections.abc import ItemsView
+
+_ = ItemsView["Model"]
+
+
+import collections.abc
+
+_ = collections.abc.ItemsView["Model"]
+
+
+from collections import abc
+
+_ = abc.ItemsView["Model"]

resources/test/fixtures/F821_5.py

@@ -0,0 +1,14 @@
+"""Test: inner class annotation."""
+
+
+class RandomClass:
+    def random_func(self) -> "InnerClass":
+        pass
+
+
+class OuterClass:
+    class InnerClass:
+        pass
+
+    def failing_func(self) -> "InnerClass":
+        return self.InnerClass()

resources/test/fixtures/N806.py

@@ -1,5 +1,11 @@
+import collections
+from collections import namedtuple
+
+
 def f():
     lower = 0
     Camel = 0
     CONSTANT = 0
     _ = 0
+    MyObj1 = collections.namedtuple("MyObj1", ["a", "b"])
+    MyObj2 = namedtuple("MyObj12", ["a", "b"])

resources/test/fixtures/N815.py

@@ -1,6 +1,12 @@
+import collections
+from collections import namedtuple
+
+
 class C:
     lower = 0
     CONSTANT = 0
     mixedCase = 0
     _mixedCase = 0
     mixed_Case = 0
+    myObj1 = collections.namedtuple("MyObj1", ["a", "b"])
+    myObj2 = namedtuple("MyObj2", ["a", "b"])

resources/test/fixtures/N816.py

@@ -1,5 +1,10 @@
+import collections
+from collections import namedtuple
+
 lower = 0
 CONSTANT = 0
 mixedCase = 0
 _mixedCase = 0
 mixed_Case = 0
+myObj1 = collections.namedtuple("MyObj1", ["a", "b"])
+myObj2 = namedtuple("MyObj2", ["a", "b"])

resources/test/fixtures/U006.py

@@ -1,3 +1,10 @@
+import typing
+
+
+def f(x: typing.List[str]) -> None:
+    ...
+
+
 from typing import List
 
 
@@ -5,8 +12,15 @@ def f(x: List[str]) -> None:
     ...
 
 
-import typing
+import typing as t
 
 
-def f(x: typing.List[str]) -> None:
+def f(x: t.List[str]) -> None:
+    ...
+
+
+from typing import List as IList
+
+
+def f(x: IList[str]) -> None:
     ...

resources/test/fixtures/YTT101.py

@@ -5,9 +5,8 @@ print(sys.version)
 
 print(sys.version[:3])
 print(version[:3])
-
-# ignore from imports with aliases, patches welcome
 print(v[:3])
+
 # the tool is timid and only flags certain numeric slices
 i = 3
 print(sys.version[:i])

resources/test/fixtures/isort/sort_similar_imports.py

@@ -0,0 +1,26 @@
+from a import b
+from a import BAD as DEF
+from a import B
+from a import Boo as DEF
+from a import B as Abc
+from a import B as A
+from a import B as DEF
+from a import b as a
+from a import b as x
+from a import b as c
+from b import c
+from a import b as d
+from a import b as y
+from b import C
+from b import c as d
+
+import A
+import a
+import b
+import B
+
+import x as y
+import x as A
+import x as Y
+import x
+import x as a

ruff_dev/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff_dev"
-version = "0.0.117"
+version = "0.0.121"
 edition = "2021"
 
 [dependencies]

src/ast/helpers.rs

@@ -3,13 +3,14 @@ use once_cell::sync::Lazy;
 use regex::Regex;
 use rustpython_ast::{Excepthandler, ExcepthandlerKind, Expr, ExprKind, Location, StmtKind};
 
-fn compose_call_path_inner<'a>(expr: &'a Expr, parts: &mut Vec<&'a str>) {
+#[inline(always)]
+fn collect_call_path_inner<'a>(expr: &'a Expr, parts: &mut Vec<&'a str>) {
     match &expr.node {
         ExprKind::Call { func, .. } => {
-            compose_call_path_inner(func, parts);
+            collect_call_path_inner(func, parts);
         }
         ExprKind::Attribute { value, attr, .. } => {
-            compose_call_path_inner(value, parts);
+            collect_call_path_inner(value, parts);
             parts.push(attr);
         }
         ExprKind::Name { id, .. } => {
@@ -20,9 +21,9 @@ fn compose_call_path_inner<'a>(expr: &'a Expr, parts: &mut Vec<&'a str>) {
 }
 
 /// Convert an `Expr` to its call path (like `List`, or `typing.List`).
+#[inline(always)]
 pub fn compose_call_path(expr: &Expr) -> Option<String> {
-    let mut segments = vec![];
-    compose_call_path_inner(expr, &mut segments);
+    let segments = collect_call_paths(expr);
     if segments.is_empty() {
         None
     } else {
@@ -30,6 +31,34 @@ pub fn compose_call_path(expr: &Expr) -> Option<String> {
     }
 }
 
+/// Convert an `Expr` to its call path segments (like ["typing", "List"]).
+#[inline(always)]
+pub fn collect_call_paths(expr: &Expr) -> Vec<&str> {
+    let mut segments = vec![];
+    collect_call_path_inner(expr, &mut segments);
+    segments
+}
+
+/// Rewrite any import aliases on a call path.
+pub fn dealias_call_path<'a>(
+    call_path: Vec<&'a str>,
+    import_aliases: &FnvHashMap<&str, &'a str>,
+) -> Vec<&'a str> {
+    if let Some(head) = call_path.first() {
+        if let Some(origin) = import_aliases.get(head) {
+            let tail = &call_path[1..];
+            let mut call_path: Vec<&str> = vec![];
+            call_path.extend(origin.split('.'));
+            call_path.extend(tail);
+            call_path
+        } else {
+            call_path
+        }
+    } else {
+        call_path
+    }
+}
+
 /// Return `true` if the `Expr` is a name or attribute reference to `${target}`.
 pub fn match_name_or_attr(expr: &Expr, target: &str) -> bool {
     match &expr.node {
@@ -39,6 +68,94 @@ pub fn match_name_or_attr(expr: &Expr, target: &str) -> bool {
     }
 }
 
+/// Return `true` if the `Expr` is a reference to `${module}.${target}`.
+///
+/// Useful for, e.g., ensuring that a `Union` reference represents
+/// `typing.Union`.
+pub fn match_module_member(
+    expr: &Expr,
+    module: &str,
+    member: &str,
+    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    import_aliases: &FnvHashMap<&str, &str>,
+) -> bool {
+    match_call_path(
+        &dealias_call_path(collect_call_paths(expr), import_aliases),
+        module,
+        member,
+        from_imports,
+    )
+}
+
+/// Return `true` if the `call_path` is a reference to `${module}.${target}`.
+///
+/// Optimized version of `match_module_member` for pre-computed call paths.
+pub fn match_call_path(
+    call_path: &[&str],
+    module: &str,
+    member: &str,
+    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+) -> bool {
+    // If we have no segments, we can't ever match.
+    let num_segments = call_path.len();
+    if num_segments == 0 {
+        return false;
+    }
+
+    // If the last segment doesn't match the member, we can't ever match.
+    if call_path[num_segments - 1] != member {
+        return false;
+    }
+
+    // We now only need the module path, so throw out the member name.
+    let call_path = &call_path[..num_segments - 1];
+    let num_segments = call_path.len();
+
+    // Case (1): It's a builtin (like `list`).
+    // Case (2a): We imported from the parent (`from typing.re import Match`,
+    // `Match`).
+    // Case (2b): We imported star from the parent (`from typing.re import *`,
+    // `Match`).
+    if num_segments == 0 {
+        module.is_empty()
+            || from_imports
+                .get(module)
+                .map(|imports| imports.contains(member) || imports.contains("*"))
+                .unwrap_or(false)
+    } else {
+        let components: Vec<&str> = module.split('.').collect();
+
+        // Case (3a): it's a fully qualified call path (`import typing`,
+        // `typing.re.Match`). Case (3b): it's a fully qualified call path (`import
+        // typing.re`, `typing.re.Match`).
+        if components == call_path {
+            return true;
+        }
+
+        // Case (4): We imported from the grandparent (`from typing import re`,
+        // `re.Match`)
+        let num_matches = (0..components.len())
+            .take(num_segments)
+            .take_while(|i| components[components.len() - 1 - i] == call_path[num_segments - 1 - i])
+            .count();
+        if num_matches > 0 {
+            let cut = components.len() - num_matches;
+            // TODO(charlie): Rewrite to avoid this allocation.
+            let module = components[..cut].join(".");
+            let member = components[cut];
+            if from_imports
+                .get(&module.as_str())
+                .map(|imports| imports.contains(member))
+                .unwrap_or(false)
+            {
+                return true;
+            }
+        }
+
+        false
+    }
+}
+
 static DUNDER_REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"__[^\s]+__").unwrap());
 
 pub fn is_assignment_to_a_dunder(node: &StmtKind) -> bool {
@@ -72,7 +189,7 @@ pub fn is_assignment_to_a_dunder(node: &StmtKind) -> bool {
 }
 
 /// Extract the names of all handled exceptions.
-pub fn extract_handler_names(handlers: &[Excepthandler]) -> Vec<String> {
+pub fn extract_handler_names(handlers: &[Excepthandler]) -> Vec<Vec<&str>> {
     let mut handler_names = vec![];
     for handler in handlers {
         match &handler.node {
@@ -80,12 +197,16 @@ pub fn extract_handler_names(handlers: &[Excepthandler]) -> Vec<String> {
                 if let Some(type_) = type_ {
                     if let ExprKind::Tuple { elts, .. } = &type_.node {
                         for type_ in elts {
-                            if let Some(name) = compose_call_path(type_) {
-                                handler_names.push(name);
+                            let call_path = collect_call_paths(type_);
+                            if !call_path.is_empty() {
+                                handler_names.push(call_path);
                             }
                         }
-                    } else if let Some(name) = compose_call_path(type_) {
-                        handler_names.push(name);
+                    } else {
+                        let call_path = collect_call_paths(type_);
+                        if !call_path.is_empty() {
+                            handler_names.push(call_path);
+                        }
                     }
                 }
             }
@@ -117,78 +238,6 @@ pub fn to_absolute(relative: &Location, base: &Location) -> Location {
     }
 }
 
-/// Return `true` if the `Expr` is a reference to `${module}.${target}`.
-///
-/// Useful for, e.g., ensuring that a `Union` reference represents
-/// `typing.Union`.
-pub fn match_module_member(
-    expr: &Expr,
-    target: &str,
-    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
-) -> bool {
-    compose_call_path(expr)
-        .map(|expr| match_call_path(&expr, target, from_imports))
-        .unwrap_or(false)
-}
-
-/// Return `true` if the `call_path` is a reference to `${module}.${target}`.
-///
-/// Optimized version of `match_module_member` for pre-computed call paths.
-pub fn match_call_path(
-    call_path: &str,
-    target: &str,
-    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
-) -> bool {
-    // Case (1a): it's the same call path (`import typing`, `typing.re.Match`).
-    // Case (1b): it's the same call path (`import typing.re`, `typing.re.Match`).
-    if call_path == target {
-        return true;
-    }
-
-    if let Some((parent, member)) = target.rsplit_once('.') {
-        // Case (2): We imported star from the parent (`from typing.re import *`,
-        // `Match`).
-        if call_path == member
-            && from_imports
-                .get(parent)
-                .map(|imports| imports.contains("*"))
-                .unwrap_or(false)
-        {
-            return true;
-        }
-
-        // Case (3): We imported from the parent (`from typing.re import Match`,
-        // `Match`)
-        if call_path == member
-            && from_imports
-                .get(parent)
-                .map(|imports| imports.contains(member))
-                .unwrap_or(false)
-        {
-            return true;
-        }
-    }
-
-    // Case (4): We imported from the grandparent (`from typing import re`,
-    // `re.Match`)
-    let mut parts = target.rsplitn(3, '.');
-    let member = parts.next();
-    let parent = parts.next();
-    let grandparent = parts.next();
-    if let (Some(member), Some(parent), Some(grandparent)) = (member, parent, grandparent) {
-        if call_path == format!("{parent}.{member}")
-            && from_imports
-                .get(grandparent)
-                .map(|imports| imports.contains(parent))
-                .unwrap_or(false)
-        {
-            return true;
-        }
-    }
-
-    false
-}
-
 #[cfg(test)]
 mod tests {
     use anyhow::Result;
@@ -197,13 +246,28 @@ mod tests {
 
     use crate::ast::helpers::match_module_member;
 
+    #[test]
+    fn builtin() -> Result<()> {
+        let expr = parser::parse_expression("list", "<filename>")?;
+        assert!(match_module_member(
+            &expr,
+            "",
+            "list",
+            &FnvHashMap::default(),
+            &FnvHashMap::default(),
+        ));
+        Ok(())
+    }
+
     #[test]
     fn fully_qualified() -> Result<()> {
         let expr = parser::parse_expression("typing.re.Match", "<filename>")?;
         assert!(match_module_member(
             &expr,
-            "typing.re.Match",
-            &FnvHashMap::default()
+            "typing.re",
+            "Match",
+            &FnvHashMap::default(),
+            &FnvHashMap::default(),
         ));
         Ok(())
     }
@@ -213,13 +277,17 @@ mod tests {
         let expr = parser::parse_expression("Match", "<filename>")?;
         assert!(!match_module_member(
             &expr,
-            "typing.re.Match",
+            "typing.re",
+            "Match",
+            &FnvHashMap::default(),
             &FnvHashMap::default(),
         ));
         let expr = parser::parse_expression("re.Match", "<filename>")?;
         assert!(!match_module_member(
             &expr,
-            "typing.re.Match",
+            "typing.re",
+            "Match",
+            &FnvHashMap::default(),
             &FnvHashMap::default(),
         ));
         Ok(())
@@ -230,8 +298,10 @@ mod tests {
         let expr = parser::parse_expression("Match", "<filename>")?;
         assert!(match_module_member(
             &expr,
-            "typing.re.Match",
-            &FnvHashMap::from_iter([("typing.re", FnvHashSet::from_iter(["*"]))])
+            "typing.re",
+            "Match",
+            &FnvHashMap::from_iter([("typing.re", FnvHashSet::from_iter(["*"]))]),
+            &FnvHashMap::default()
         ));
         Ok(())
     }
@@ -241,8 +311,10 @@ mod tests {
         let expr = parser::parse_expression("Match", "<filename>")?;
         assert!(match_module_member(
             &expr,
-            "typing.re.Match",
-            &FnvHashMap::from_iter([("typing.re", FnvHashSet::from_iter(["Match"]))])
+            "typing.re",
+            "Match",
+            &FnvHashMap::from_iter([("typing.re", FnvHashSet::from_iter(["Match"]))]),
+            &FnvHashMap::default()
         ));
         Ok(())
     }
@@ -252,8 +324,67 @@ mod tests {
         let expr = parser::parse_expression("re.Match", "<filename>")?;
         assert!(match_module_member(
             &expr,
-            "typing.re.Match",
-            &FnvHashMap::from_iter([("typing", FnvHashSet::from_iter(["re"]))])
+            "typing.re",
+            "Match",
+            &FnvHashMap::from_iter([("typing", FnvHashSet::from_iter(["re"]))]),
+            &FnvHashMap::default()
+        ));
+
+        let expr = parser::parse_expression("match.Match", "<filename>")?;
+        assert!(match_module_member(
+            &expr,
+            "typing.re.match",
+            "Match",
+            &FnvHashMap::from_iter([("typing.re", FnvHashSet::from_iter(["match"]))]),
+            &FnvHashMap::default()
+        ));
+
+        let expr = parser::parse_expression("re.match.Match", "<filename>")?;
+        assert!(match_module_member(
+            &expr,
+            "typing.re.match",
+            "Match",
+            &FnvHashMap::from_iter([("typing", FnvHashSet::from_iter(["re"]))]),
+            &FnvHashMap::default()
+        ));
+        Ok(())
+    }
+
+    #[test]
+    fn from_alias() -> Result<()> {
+        let expr = parser::parse_expression("IMatch", "<filename>")?;
+        assert!(match_module_member(
+            &expr,
+            "typing.re",
+            "Match",
+            &FnvHashMap::from_iter([("typing.re", FnvHashSet::from_iter(["Match"]))]),
+            &FnvHashMap::from_iter([("IMatch", "Match")]),
+        ));
+        Ok(())
+    }
+
+    #[test]
+    fn from_aliased_parent() -> Result<()> {
+        let expr = parser::parse_expression("t.Match", "<filename>")?;
+        assert!(match_module_member(
+            &expr,
+            "typing.re",
+            "Match",
+            &FnvHashMap::default(),
+            &FnvHashMap::from_iter([("t", "typing.re")]),
+        ));
+        Ok(())
+    }
+
+    #[test]
+    fn from_aliased_grandparent() -> Result<()> {
+        let expr = parser::parse_expression("t.re.Match", "<filename>")?;
+        assert!(match_module_member(
+            &expr,
+            "typing.re",
+            "Match",
+            &FnvHashMap::default(),
+            &FnvHashMap::from_iter([("t", "typing")]),
         ));
         Ok(())
     }

src/ast/types.rs

@@ -1,6 +1,6 @@
-use std::collections::BTreeMap;
 use std::sync::atomic::{AtomicUsize, Ordering};
 
+use fnv::FnvHashMap;
 use rustpython_ast::{Expr, Keyword};
 use rustpython_parser::ast::{Located, Location};
 
@@ -54,7 +54,7 @@ pub struct Scope<'a> {
     pub id: usize,
     pub kind: ScopeKind<'a>,
     pub import_starred: bool,
-    pub values: BTreeMap<String, Binding>,
+    pub values: FnvHashMap<String, Binding>,
 }
 
 impl<'a> Scope<'a> {
@@ -63,7 +63,7 @@ impl<'a> Scope<'a> {
             id: id(),
             kind,
             import_starred: false,
-            values: BTreeMap::new(),
+            values: FnvHashMap::default(),
         }
     }
 }

src/autofix/fixer.rs

@@ -61,7 +61,7 @@ fn apply_fixes<'a>(
 ) -> Cow<'a, str> {
     let mut output = RopeBuilder::new();
     let mut last_pos: Location = Location::new(1, 0);
-    let mut applied: BTreeSet<&Patch> = BTreeSet::new();
+    let mut applied: BTreeSet<&Patch> = BTreeSet::default();
 
     for fix in fixes.sorted_by_key(|fix| fix.patch.location) {
         // If we already applied an identical fix as part of another correction, skip

src/cache.rs

@@ -23,7 +23,7 @@ use crate::autofix::fixer;
 use crate::message::Message;
 use crate::settings::Settings;
 
-const VERSION: &str = env!("CARGO_PKG_VERSION");
+const CARGO_PKG_VERSION: &str = env!("CARGO_PKG_VERSION");
 
 #[derive(Serialize, Deserialize)]
 struct CacheMetadata {
@@ -89,7 +89,7 @@ fn cache_key(path: &Path, settings: &Settings, autofix: &fixer::Mode) -> String
     format!(
         "{}@{}@{}",
         path.absolutize().unwrap().to_string_lossy(),
-        VERSION,
+        CARGO_PKG_VERSION,
         hasher.finish()
     )
 }

src/check_ast.rs

@@ -5,6 +5,7 @@ use std::ops::Deref;
 use std::path::Path;
 
 use fnv::{FnvHashMap, FnvHashSet};
+use itertools::Itertools;
 use log::error;
 use rustpython_parser::ast::{
     Arg, Arguments, Constant, Excepthandler, ExcepthandlerKind, Expr, ExprContext, ExprKind,
@@ -12,7 +13,9 @@ use rustpython_parser::ast::{
 };
 use rustpython_parser::parser;
 
-use crate::ast::helpers::{extract_handler_names, match_module_member};
+use crate::ast::helpers::{
+    collect_call_paths, dealias_call_path, extract_handler_names, match_call_path,
+};
 use crate::ast::operations::extract_all_names;
 use crate::ast::relocate::relocate_expr;
 use crate::ast::types::{
@@ -54,6 +57,7 @@ pub struct Checker<'a> {
     pub(crate) deletions: FnvHashSet<usize>,
     // Import tracking.
     pub(crate) from_imports: FnvHashMap<&'a str, FnvHashSet<&'a str>>,
+    pub(crate) import_aliases: FnvHashMap<&'a str, &'a str>,
     // Retain all scopes and parent nodes, along with a stack of indexes to track which are active
     // at various points in time.
     pub(crate) parents: Vec<&'a Stmt>,
@@ -61,7 +65,7 @@ pub struct Checker<'a> {
     scopes: Vec<Scope<'a>>,
     scope_stack: Vec<usize>,
     dead_scopes: Vec<usize>,
-    deferred_string_annotations: Vec<(Range, &'a str)>,
+    deferred_string_annotations: Vec<(Range, &'a str, Vec<usize>, Vec<usize>)>,
     deferred_annotations: Vec<(&'a Expr, Vec<usize>, Vec<usize>)>,
     deferred_functions: Vec<(&'a Stmt, Vec<usize>, Vec<usize>, VisibleScope)>,
     deferred_lambdas: Vec<(&'a Expr, Vec<usize>, Vec<usize>)>,
@@ -75,7 +79,7 @@ pub struct Checker<'a> {
     seen_import_boundary: bool,
     futures_allowed: bool,
     annotations_future_enabled: bool,
-    except_handlers: Vec<Vec<String>>,
+    except_handlers: Vec<Vec<Vec<&'a str>>>,
 }
 
 impl<'a> Checker<'a> {
@@ -94,6 +98,7 @@ impl<'a> Checker<'a> {
             definitions: Default::default(),
             deletions: Default::default(),
             from_imports: Default::default(),
+            import_aliases: Default::default(),
             parents: Default::default(),
             parent_stack: Default::default(),
             scopes: Default::default(),
@@ -154,14 +159,16 @@ impl<'a> Checker<'a> {
     }
 
     /// Return `true` if the `Expr` is a reference to `typing.${target}`.
-    pub fn match_typing_module(&self, expr: &Expr, target: &str) -> bool {
-        match_module_member(expr, &format!("typing.{target}"), &self.from_imports)
+    pub fn match_typing_expr(&self, expr: &Expr, target: &str) -> bool {
+        let call_path = dealias_call_path(collect_call_paths(expr), &self.import_aliases);
+        self.match_typing_call_path(&call_path, target)
+    }
+
+    /// Return `true` if the call path is a reference to `typing.${target}`.
+    pub fn match_typing_call_path(&self, call_path: &[&str], target: &str) -> bool {
+        match_call_path(call_path, "typing", target, &self.from_imports)
             || (typing::in_extensions(target)
-                && match_module_member(
-                    expr,
-                    &format!("typing_extensions.{target}"),
-                    &self.from_imports,
-                ))
+                && match_call_path(call_path, "typing_extensions", target, &self.from_imports))
     }
 }
 
@@ -452,6 +459,14 @@ where
                     flake8_bugbear::plugins::useless_expression(self, body);
                 }
 
+                if self.settings.enabled.contains(&CheckCode::B024)
+                    || self.settings.enabled.contains(&CheckCode::B027)
+                {
+                    flake8_bugbear::plugins::abstract_base_class(
+                        self, stmt, name, bases, keywords, body,
+                    );
+                }
+
                 self.check_builtin_shadowing(name, Range::from_located(stmt), false);
 
                 for expr in bases {
@@ -516,13 +531,38 @@ where
                                     full_name.to_string(),
                                     self.binding_context(),
                                 ),
-                                used: None,
+                                // Treat explicit re-export as usage (e.g., `import applications
+                                // as applications`).
+                                used: if alias
+                                    .node
+                                    .asname
+                                    .as_ref()
+                                    .map(|asname| asname == &alias.node.name)
+                                    .unwrap_or(false)
+                                {
+                                    Some((
+                                        self.scopes[*(self
+                                            .scope_stack
+                                            .last()
+                                            .expect("No current scope found."))]
+                                        .id,
+                                        Range::from_located(stmt),
+                                    ))
+                                } else {
+                                    None
+                                },
                                 range: Range::from_located(stmt),
                             },
                         )
                     }
 
                     if let Some(asname) = &alias.node.asname {
+                        for alias in names {
+                            if let Some(asname) = &alias.node.asname {
+                                self.import_aliases.insert(asname, &alias.node.name);
+                            }
+                        }
+
                         let name = alias.node.name.split('.').last().unwrap();
                         if self.settings.enabled.contains(&CheckCode::N811) {
                             if let Some(check) =
@@ -591,6 +631,11 @@ where
                                     .map(|alias| alias.node.name.as_str()),
                             )
                     }
+                    for alias in names {
+                        if let Some(asname) = &alias.node.asname {
+                            self.import_aliases.insert(asname, &alias.node.name);
+                        }
+                    }
                 }
 
                 if self.settings.enabled.contains(&CheckCode::E402) {
@@ -828,10 +873,15 @@ where
                     flake8_bugbear::plugins::assert_raises_exception(self, stmt, items);
                 }
             }
-            StmtKind::For { target, body, .. } => {
+            StmtKind::For {
+                target, body, iter, ..
+            } => {
                 if self.settings.enabled.contains(&CheckCode::B007) {
                     flake8_bugbear::plugins::unused_loop_control_variable(self, target, body);
                 }
+                if self.settings.enabled.contains(&CheckCode::B020) {
+                    flake8_bugbear::plugins::loop_variable_overrides_iterator(self, target, iter);
+                }
             }
             StmtKind::Try { handlers, .. } => {
                 if self.settings.enabled.contains(&CheckCode::F707) {
@@ -997,8 +1047,12 @@ where
                 ..
             } = &expr.node
             {
-                self.deferred_string_annotations
-                    .push((Range::from_located(expr), value));
+                self.deferred_string_annotations.push((
+                    Range::from_located(expr),
+                    value,
+                    self.scope_stack.clone(),
+                    self.parent_stack.clone(),
+                ));
             } else {
                 self.deferred_annotations.push((
                     expr,
@@ -1014,12 +1068,12 @@ where
             ExprKind::Subscript { value, slice, .. } => {
                 // Ex) typing.List[...]
                 if self.settings.enabled.contains(&CheckCode::U007)
-                    && self.settings.target_version >= PythonVersion::Py39
+                    && self.settings.target_version >= PythonVersion::Py310
                 {
                     pyupgrade::plugins::use_pep604_annotation(self, expr, value, slice);
                 }
 
-                if self.match_typing_module(value, "Literal") {
+                if self.match_typing_expr(value, "Literal") {
                     self.in_literal = true;
                 }
 
@@ -1053,7 +1107,11 @@ where
                         // Ex) List[...]
                         if self.settings.enabled.contains(&CheckCode::U006)
                             && self.settings.target_version >= PythonVersion::Py39
-                            && typing::is_pep585_builtin(expr, &self.from_imports)
+                            && typing::is_pep585_builtin(
+                                expr,
+                                &self.from_imports,
+                                &self.import_aliases,
+                            )
                         {
                             pyupgrade::plugins::use_pep585_annotation(self, expr, id);
                         }
@@ -1085,7 +1143,7 @@ where
                 // Ex) typing.List[...]
                 if self.settings.enabled.contains(&CheckCode::U006)
                     && self.settings.target_version >= PythonVersion::Py39
-                    && typing::is_pep585_builtin(expr, &self.from_imports)
+                    && typing::is_pep585_builtin(expr, &self.from_imports, &self.import_aliases)
                 {
                     pyupgrade::plugins::use_pep585_annotation(self, expr, attr);
                 }
@@ -1138,6 +1196,9 @@ where
                         flake8_bugbear::plugins::setattr_with_constant(self, expr, func, args);
                     }
                 }
+                if self.settings.enabled.contains(&CheckCode::B022) {
+                    flake8_bugbear::plugins::useless_contextlib_suppress(self, expr, args);
+                }
                 if self.settings.enabled.contains(&CheckCode::B026) {
                     flake8_bugbear::plugins::star_arg_unpacking_after_keyword_arg(
                         self, args, keywords,
@@ -1517,8 +1578,12 @@ where
                 ..
             } => {
                 if self.in_annotation && !self.in_literal {
-                    self.deferred_string_annotations
-                        .push((Range::from_located(expr), value));
+                    self.deferred_string_annotations.push((
+                        Range::from_located(expr),
+                        value,
+                        self.scope_stack.clone(),
+                        self.parent_stack.clone(),
+                    ));
                 }
                 if self.settings.enabled.contains(&CheckCode::S104) {
                     if let Some(check) = flake8_bandit::plugins::hardcoded_bind_all_interfaces(
@@ -1599,12 +1664,13 @@ where
                 args,
                 keywords,
             } => {
-                if self.match_typing_module(func, "ForwardRef") {
+                let call_path = dealias_call_path(collect_call_paths(func), &self.import_aliases);
+                if self.match_typing_call_path(&call_path, "ForwardRef") {
                     self.visit_expr(func);
                     for expr in args {
                         self.visit_annotation(expr);
                     }
-                } else if self.match_typing_module(func, "cast") {
+                } else if self.match_typing_call_path(&call_path, "cast") {
                     self.visit_expr(func);
                     if !args.is_empty() {
                         self.visit_annotation(&args[0]);
@@ -1612,12 +1678,12 @@ where
                     for expr in args.iter().skip(1) {
                         self.visit_expr(expr);
                     }
-                } else if self.match_typing_module(func, "NewType") {
+                } else if self.match_typing_call_path(&call_path, "NewType") {
                     self.visit_expr(func);
                     for expr in args.iter().skip(1) {
                         self.visit_annotation(expr);
                     }
-                } else if self.match_typing_module(func, "TypeVar") {
+                } else if self.match_typing_call_path(&call_path, "TypeVar") {
                     self.visit_expr(func);
                     for expr in args.iter().skip(1) {
                         self.visit_annotation(expr);
@@ -1634,7 +1700,7 @@ where
                             }
                         }
                     }
-                } else if self.match_typing_module(func, "NamedTuple") {
+                } else if self.match_typing_call_path(&call_path, "NamedTuple") {
                     self.visit_expr(func);
 
                     // Ex) NamedTuple("a", [("a", int)])
@@ -1666,7 +1732,7 @@ where
                         let KeywordData { value, .. } = &keyword.node;
                         self.visit_annotation(value);
                     }
-                } else if self.match_typing_module(func, "TypedDict") {
+                } else if self.match_typing_call_path(&call_path, "TypedDict") {
                     self.visit_expr(func);
 
                     // Ex) TypedDict("a", {"a": int})
@@ -1705,7 +1771,11 @@ where
                     visitor::walk_expr(self, expr);
                 } else {
                     self.in_subscript = true;
-                    match typing::match_annotated_subscript(value, &self.from_imports) {
+                    match typing::match_annotated_subscript(
+                        value,
+                        &self.from_imports,
+                        &self.import_aliases,
+                    ) {
                         Some(subscript) => {
                             match subscript {
                                 // Ex) Optional[int]
@@ -2071,6 +2141,7 @@ impl<'a> Checker<'a> {
             let mut import_starred = false;
             for scope_index in self.scope_stack.iter().rev() {
                 let scope = &mut self.scopes[*scope_index];
+
                 if matches!(scope.kind, ScopeKind::Class(_)) {
                     if id == "__class__" {
                         return;
@@ -2117,7 +2188,10 @@ impl<'a> Checker<'a> {
 
                 // Avoid flagging if NameError is handled.
                 if let Some(handler_names) = self.except_handlers.last() {
-                    if handler_names.contains(&"NameError".to_string()) {
+                    if handler_names
+                        .iter()
+                        .any(|call_path| call_path.len() == 1 && call_path[0] == "NameError")
+                    {
                         return;
                     }
                 }
@@ -2144,32 +2218,22 @@ impl<'a> Checker<'a> {
             }
 
             if self.settings.enabled.contains(&CheckCode::N806) {
-                let current =
-                    &self.scopes[*(self.scope_stack.last().expect("No current scope found."))];
-                if let Some(check) =
-                    pep8_naming::checks::non_lowercase_variable_in_function(current, expr, id)
-                {
-                    self.add_check(check);
+                if matches!(self.current_scope().kind, ScopeKind::Function(..)) {
+                    pep8_naming::plugins::non_lowercase_variable_in_function(self, expr, parent, id)
                 }
             }
 
             if self.settings.enabled.contains(&CheckCode::N815) {
-                let current =
-                    &self.scopes[*(self.scope_stack.last().expect("No current scope found."))];
-                if let Some(check) =
-                    pep8_naming::checks::mixed_case_variable_in_class_scope(current, expr, id)
-                {
-                    self.add_check(check);
+                if matches!(self.current_scope().kind, ScopeKind::Class(..)) {
+                    pep8_naming::plugins::mixed_case_variable_in_class_scope(self, expr, parent, id)
                 }
             }
 
             if self.settings.enabled.contains(&CheckCode::N816) {
-                let current =
-                    &self.scopes[*(self.scope_stack.last().expect("No current scope found."))];
-                if let Some(check) =
-                    pep8_naming::checks::mixed_case_variable_in_global_scope(current, expr, id)
-                {
-                    self.add_check(check);
+                if matches!(self.current_scope().kind, ScopeKind::Module) {
+                    pep8_naming::plugins::mixed_case_variable_in_global_scope(
+                        self, expr, parent, id,
+                    )
                 }
             }
 
@@ -2294,8 +2358,8 @@ impl<'a> Checker<'a> {
 
     fn check_deferred_annotations(&mut self) {
         while let Some((expr, scopes, parents)) = self.deferred_annotations.pop() {
-            self.parent_stack = parents;
             self.scope_stack = scopes;
+            self.parent_stack = parents;
             self.visit_expr(expr);
         }
     }
@@ -2304,10 +2368,14 @@ impl<'a> Checker<'a> {
     where
         'b: 'a,
     {
-        while let Some((range, expression)) = self.deferred_string_annotations.pop() {
+        let mut stacks = vec![];
+        while let Some((range, expression, scopes, parents)) =
+            self.deferred_string_annotations.pop()
+        {
             if let Ok(mut expr) = parser::parse_expression(expression, "<filename>") {
                 relocate_expr(&mut expr, range);
                 allocator.push(expr);
+                stacks.push((scopes, parents));
             } else {
                 if self.settings.enabled.contains(&CheckCode::F722) {
                     self.add_check(Check::new(
@@ -2317,7 +2385,9 @@ impl<'a> Checker<'a> {
                 }
             }
         }
-        for expr in allocator {
+        for (expr, (scopes, parents)) in allocator.iter().zip(stacks) {
+            self.scope_stack = scopes;
+            self.parent_stack = parents;
             self.visit_expr(expr);
         }
     }
@@ -2443,7 +2513,7 @@ impl<'a> Checker<'a> {
                 let mut unused: BTreeMap<(ImportKind, usize, Option<usize>), Vec<&str>> =
                     BTreeMap::new();
 
-                for (name, binding) in scope.values.iter().rev() {
+                for (name, binding) in scope.values.iter() {
                     let used = binding.used.is_some()
                         || all_names
                             .map(|names| names.contains(name))
@@ -2452,25 +2522,25 @@ impl<'a> Checker<'a> {
                     if !used {
                         match &binding.kind {
                             BindingKind::FromImportation(_, full_name, context) => {
-                                let full_names = unused
+                                unused
                                     .entry((
                                         ImportKind::ImportFrom,
                                         context.defined_by,
                                         context.defined_in,
                                     ))
-                                    .or_default();
-                                full_names.push(full_name);
+                                    .or_default()
+                                    .push(full_name);
                             }
                             BindingKind::Importation(_, full_name, context)
                             | BindingKind::SubmoduleImportation(_, full_name, context) => {
-                                let full_names = unused
+                                unused
                                     .entry((
                                         ImportKind::Import,
                                         context.defined_by,
                                         context.defined_in,
                                     ))
-                                    .or_default();
-                                full_names.push(full_name);
+                                    .or_default()
+                                    .push(full_name);
                             }
                             _ => {}
                         }
@@ -2511,7 +2581,7 @@ impl<'a> Checker<'a> {
                     if self.path.ends_with("__init__.py") {
                         checks.push(Check::new(
                             CheckKind::UnusedImport(
-                                full_names.into_iter().map(String::from).collect(),
+                                full_names.into_iter().sorted().map(String::from).collect(),
                                 true,
                             ),
                             Range::from_located(child),
@@ -2519,7 +2589,7 @@ impl<'a> Checker<'a> {
                     } else {
                         let mut check = Check::new(
                             CheckKind::UnusedImport(
-                                full_names.into_iter().map(String::from).collect(),
+                                full_names.into_iter().sorted().map(String::from).collect(),
                                 false,
                             ),
                             Range::from_located(child),
@@ -2712,8 +2782,5 @@ pub fn check_ast(
     // Check docstrings.
     checker.check_definitions();
 
-    // Check import blocks.
-    // checker.check_import_blocks();
-
     checker.checks
 }

src/checks.rs

@@ -95,9 +95,13 @@ pub enum CheckCode {
     B017,
     B018,
     B019,
+    B020,
     B021,
+    B022,
+    B024,
     B025,
     B026,
+    B027,
     // flake8-comprehensions
     C400,
     C401,
@@ -396,9 +400,13 @@ pub enum CheckKind {
     NoAssertRaisesException,
     UselessExpression,
     CachedInstanceMethod,
+    LoopVariableOverridesIterator(String),
     FStringDocstring,
+    UselessContextlibSuppress,
+    AbstractBaseClassWithoutAbstractMethod(String),
     DuplicateTryBlockException(String),
     StarArgUnpackingAfterKeywordArg,
+    EmptyMethodWithoutAbstractDecorator(String),
     // flake8-comprehensions
     UnnecessaryGeneratorList,
     UnnecessaryGeneratorSet,
@@ -639,9 +647,13 @@ impl CheckCode {
             CheckCode::B017 => CheckKind::NoAssertRaisesException,
             CheckCode::B018 => CheckKind::UselessExpression,
             CheckCode::B019 => CheckKind::CachedInstanceMethod,
+            CheckCode::B020 => CheckKind::LoopVariableOverridesIterator("...".to_string()),
             CheckCode::B021 => CheckKind::FStringDocstring,
+            CheckCode::B022 => CheckKind::UselessContextlibSuppress,
+            CheckCode::B024 => CheckKind::AbstractBaseClassWithoutAbstractMethod("...".to_string()),
             CheckCode::B025 => CheckKind::DuplicateTryBlockException("Exception".to_string()),
             CheckCode::B026 => CheckKind::StarArgUnpackingAfterKeywordArg,
+            CheckCode::B027 => CheckKind::EmptyMethodWithoutAbstractDecorator("...".to_string()),
             // flake8-comprehensions
             CheckCode::C400 => CheckKind::UnnecessaryGeneratorList,
             CheckCode::C401 => CheckKind::UnnecessaryGeneratorSet,
@@ -881,9 +893,13 @@ impl CheckCode {
             CheckCode::B017 => CheckCategory::Flake8Bugbear,
             CheckCode::B018 => CheckCategory::Flake8Bugbear,
             CheckCode::B019 => CheckCategory::Flake8Bugbear,
+            CheckCode::B020 => CheckCategory::Flake8Bugbear,
             CheckCode::B021 => CheckCategory::Flake8Bugbear,
+            CheckCode::B022 => CheckCategory::Flake8Bugbear,
+            CheckCode::B024 => CheckCategory::Flake8Bugbear,
             CheckCode::B025 => CheckCategory::Flake8Bugbear,
             CheckCode::B026 => CheckCategory::Flake8Bugbear,
+            CheckCode::B027 => CheckCategory::Flake8Bugbear,
             CheckCode::C400 => CheckCategory::Flake8Comprehensions,
             CheckCode::C401 => CheckCategory::Flake8Comprehensions,
             CheckCode::C402 => CheckCategory::Flake8Comprehensions,
@@ -1086,9 +1102,13 @@ impl CheckKind {
             CheckKind::NoAssertRaisesException => &CheckCode::B017,
             CheckKind::UselessExpression => &CheckCode::B018,
             CheckKind::CachedInstanceMethod => &CheckCode::B019,
+            CheckKind::LoopVariableOverridesIterator(_) => &CheckCode::B020,
             CheckKind::FStringDocstring => &CheckCode::B021,
+            CheckKind::UselessContextlibSuppress => &CheckCode::B022,
+            CheckKind::AbstractBaseClassWithoutAbstractMethod(_) => &CheckCode::B024,
             CheckKind::DuplicateTryBlockException(_) => &CheckCode::B025,
             CheckKind::StarArgUnpackingAfterKeywordArg => &CheckCode::B026,
+            CheckKind::EmptyMethodWithoutAbstractDecorator(_) => &CheckCode::B027,
             // flake8-comprehensions
             CheckKind::UnnecessaryGeneratorList => &CheckCode::C400,
             CheckKind::UnnecessaryGeneratorSet => &CheckCode::C401,
@@ -1457,9 +1477,20 @@ impl CheckKind {
             CheckKind::CachedInstanceMethod => "Use of `functools.lru_cache` or `functools.cache` \
                                                 on methods can lead to memory leaks"
                 .to_string(),
+            CheckKind::LoopVariableOverridesIterator(name) => {
+                format!("Loop control variable `{name}` overrides iterable it iterates")
+            }
             CheckKind::FStringDocstring => "f-string used as docstring. This will be interpreted \
                                             by python as a joined string rather than a docstring."
                 .to_string(),
+            CheckKind::UselessContextlibSuppress => {
+                "No arguments passed to `contextlib.suppress`. No exceptions will be suppressed \
+                 and therefore this context manager is redundant"
+                    .to_string()
+            }
+            CheckKind::AbstractBaseClassWithoutAbstractMethod(name) => {
+                format!("`{name}` is an abstract base class, but it has no abstract methods")
+            }
             CheckKind::DuplicateTryBlockException(name) => {
                 format!("try-except block with duplicate exception `{name}`")
             }
@@ -1469,6 +1500,12 @@ impl CheckKind {
                  unpacked sequence, and this change of ordering can surprise and mislead readers."
                     .to_string()
             }
+            CheckKind::EmptyMethodWithoutAbstractDecorator(name) => {
+                format!(
+                    "`{name}` is an empty method in an abstract base class, but has no abstract \
+                     decorator"
+                )
+            }
             // flake8-comprehensions
             CheckKind::UnnecessaryGeneratorList => {
                 "Unnecessary generator (rewrite as a `list` comprehension)".to_string()

src/checks_gen.rs

@@ -56,9 +56,13 @@ pub enum CheckCodePrefix {
     B018,
     B019,
     B02,
+    B020,
     B021,
+    B022,
+    B024,
     B025,
     B026,
+    B027,
     C,
     C4,
     C40,
@@ -383,9 +387,13 @@ impl CheckCodePrefix {
                 CheckCode::B017,
                 CheckCode::B018,
                 CheckCode::B019,
+                CheckCode::B020,
                 CheckCode::B021,
+                CheckCode::B022,
+                CheckCode::B024,
                 CheckCode::B025,
                 CheckCode::B026,
+                CheckCode::B027,
             ],
             CheckCodePrefix::B0 => vec![
                 CheckCode::B002,
@@ -406,9 +414,13 @@ impl CheckCodePrefix {
                 CheckCode::B017,
                 CheckCode::B018,
                 CheckCode::B019,
+                CheckCode::B020,
                 CheckCode::B021,
+                CheckCode::B022,
+                CheckCode::B024,
                 CheckCode::B025,
                 CheckCode::B026,
+                CheckCode::B027,
             ],
             CheckCodePrefix::B00 => vec![
                 CheckCode::B002,
@@ -450,10 +462,22 @@ impl CheckCodePrefix {
             CheckCodePrefix::B017 => vec![CheckCode::B017],
             CheckCodePrefix::B018 => vec![CheckCode::B018],
             CheckCodePrefix::B019 => vec![CheckCode::B019],
-            CheckCodePrefix::B02 => vec![CheckCode::B021, CheckCode::B025, CheckCode::B026],
+            CheckCodePrefix::B02 => vec![
+                CheckCode::B020,
+                CheckCode::B021,
+                CheckCode::B022,
+                CheckCode::B024,
+                CheckCode::B025,
+                CheckCode::B026,
+                CheckCode::B027,
+            ],
+            CheckCodePrefix::B020 => vec![CheckCode::B020],
             CheckCodePrefix::B021 => vec![CheckCode::B021],
+            CheckCodePrefix::B022 => vec![CheckCode::B022],
+            CheckCodePrefix::B024 => vec![CheckCode::B024],
             CheckCodePrefix::B025 => vec![CheckCode::B025],
             CheckCodePrefix::B026 => vec![CheckCode::B026],
+            CheckCodePrefix::B027 => vec![CheckCode::B027],
             CheckCodePrefix::C => vec![
                 CheckCode::C400,
                 CheckCode::C401,
@@ -1194,9 +1218,13 @@ impl CheckCodePrefix {
             CheckCodePrefix::B018 => PrefixSpecificity::Explicit,
             CheckCodePrefix::B019 => PrefixSpecificity::Explicit,
             CheckCodePrefix::B02 => PrefixSpecificity::Tens,
+            CheckCodePrefix::B020 => PrefixSpecificity::Explicit,
             CheckCodePrefix::B021 => PrefixSpecificity::Explicit,
+            CheckCodePrefix::B022 => PrefixSpecificity::Explicit,
+            CheckCodePrefix::B024 => PrefixSpecificity::Explicit,
             CheckCodePrefix::B025 => PrefixSpecificity::Explicit,
             CheckCodePrefix::B026 => PrefixSpecificity::Explicit,
+            CheckCodePrefix::B027 => PrefixSpecificity::Explicit,
             CheckCodePrefix::C => PrefixSpecificity::Category,
             CheckCodePrefix::C4 => PrefixSpecificity::Hundreds,
             CheckCodePrefix::C40 => PrefixSpecificity::Tens,

src/cli.rs

@@ -1,8 +1,8 @@
-use std::collections::BTreeMap;
 use std::fmt;
 use std::path::PathBuf;
 
 use clap::{command, Parser};
+use fnv::FnvHashMap;
 use log::warn;
 use regex::Regex;
 
@@ -87,6 +87,10 @@ pub struct Cli {
     /// The minimum Python version that should be supported.
     #[arg(long)]
     pub target_version: Option<PythonVersion>,
+    /// Set the line-length for length-associated checks and automatic
+    /// formatting.
+    #[arg(long)]
+    pub line_length: Option<usize>,
     /// Round-trip auto-formatting.
     // TODO(charlie): This should be a sub-command.
     #[arg(long, hide = true)]
@@ -120,6 +124,8 @@ pub fn extract_log_level(cli: &Cli) -> LogLevel {
         LogLevel::Quiet
     } else if cli.verbose {
         LogLevel::Verbose
+    } else if matches!(cli.format, SerializationFormat::Json) {
+        LogLevel::Quiet
     } else {
         LogLevel::Default
     }
@@ -188,7 +194,7 @@ pub fn collect_per_file_ignores(
     pairs: Vec<PatternPrefixPair>,
     project_root: &Option<PathBuf>,
 ) -> Vec<PerFileIgnore> {
-    let mut per_file_ignores: BTreeMap<String, Vec<CheckCodePrefix>> = BTreeMap::new();
+    let mut per_file_ignores: FnvHashMap<String, Vec<CheckCodePrefix>> = FnvHashMap::default();
     for pair in pairs {
         per_file_ignores
             .entry(pair.pattern)

src/docstrings/google.rs

@@ -1,11 +1,10 @@
 //! Abstractions for Google-style docstrings.
 
-use std::collections::BTreeSet;
-
+use fnv::FnvHashSet;
 use once_cell::sync::Lazy;
 
-pub(crate) static GOOGLE_SECTION_NAMES: Lazy<BTreeSet<&'static str>> = Lazy::new(|| {
-    BTreeSet::from([
+pub(crate) static GOOGLE_SECTION_NAMES: Lazy<FnvHashSet<&'static str>> = Lazy::new(|| {
+    FnvHashSet::from_iter([
         "Args",
         "Arguments",
         "Attention",
@@ -37,35 +36,36 @@ pub(crate) static GOOGLE_SECTION_NAMES: Lazy<BTreeSet<&'static str>> = Lazy::new
     ])
 });
 
-pub(crate) static LOWERCASE_GOOGLE_SECTION_NAMES: Lazy<BTreeSet<&'static str>> = Lazy::new(|| {
-    BTreeSet::from([
-        "args",
-        "arguments",
-        "attention",
-        "attributes",
-        "caution",
-        "danger",
-        "error",
-        "example",
-        "examples",
-        "hint",
-        "important",
-        "keyword args",
-        "keyword arguments",
-        "methods",
-        "note",
-        "notes",
-        "return",
-        "returns",
-        "raises",
-        "references",
-        "see also",
-        "tip",
-        "todo",
-        "warning",
-        "warnings",
-        "warns",
-        "yield",
-        "yields",
-    ])
-});
+pub(crate) static LOWERCASE_GOOGLE_SECTION_NAMES: Lazy<FnvHashSet<&'static str>> =
+    Lazy::new(|| {
+        FnvHashSet::from_iter([
+            "args",
+            "arguments",
+            "attention",
+            "attributes",
+            "caution",
+            "danger",
+            "error",
+            "example",
+            "examples",
+            "hint",
+            "important",
+            "keyword args",
+            "keyword arguments",
+            "methods",
+            "note",
+            "notes",
+            "return",
+            "returns",
+            "raises",
+            "references",
+            "see also",
+            "tip",
+            "todo",
+            "warning",
+            "warnings",
+            "warns",
+            "yield",
+            "yields",
+        ])
+    });

src/docstrings/numpy.rs

@@ -1,11 +1,10 @@
 //! Abstractions for NumPy-style docstrings.
 
-use std::collections::BTreeSet;
-
+use fnv::FnvHashSet;
 use once_cell::sync::Lazy;
 
-pub(crate) static LOWERCASE_NUMPY_SECTION_NAMES: Lazy<BTreeSet<&'static str>> = Lazy::new(|| {
-    BTreeSet::from([
+pub(crate) static LOWERCASE_NUMPY_SECTION_NAMES: Lazy<FnvHashSet<&'static str>> = Lazy::new(|| {
+    FnvHashSet::from_iter([
         "short summary",
         "extended summary",
         "parameters",
@@ -22,8 +21,8 @@ pub(crate) static LOWERCASE_NUMPY_SECTION_NAMES: Lazy<BTreeSet<&'static str>> =
     ])
 });
 
-pub(crate) static NUMPY_SECTION_NAMES: Lazy<BTreeSet<&'static str>> = Lazy::new(|| {
-    BTreeSet::from([
+pub(crate) static NUMPY_SECTION_NAMES: Lazy<FnvHashSet<&'static str>> = Lazy::new(|| {
+    FnvHashSet::from_iter([
         "Short Summary",
         "Extended Summary",
         "Parameters",

src/docstrings/styles.rs

@@ -1,5 +1,4 @@
-use std::collections::BTreeSet;
-
+use fnv::FnvHashSet;
 use once_cell::sync::Lazy;
 
 use crate::docstrings::google::{GOOGLE_SECTION_NAMES, LOWERCASE_GOOGLE_SECTION_NAMES};
@@ -11,14 +10,14 @@ pub(crate) enum SectionStyle {
 }
 
 impl SectionStyle {
-    pub(crate) fn section_names(&self) -> &Lazy<BTreeSet<&'static str>> {
+    pub(crate) fn section_names(&self) -> &Lazy<FnvHashSet<&'static str>> {
         match self {
             SectionStyle::NumPy => &NUMPY_SECTION_NAMES,
             SectionStyle::Google => &GOOGLE_SECTION_NAMES,
         }
     }
 
-    pub(crate) fn lowercase_section_names(&self) -> &Lazy<BTreeSet<&'static str>> {
+    pub(crate) fn lowercase_section_names(&self) -> &Lazy<FnvHashSet<&'static str>> {
         match self {
             SectionStyle::NumPy => &LOWERCASE_NUMPY_SECTION_NAMES,
             SectionStyle::Google => &LOWERCASE_GOOGLE_SECTION_NAMES,

src/flake8_2020/plugins.rs

@@ -7,7 +7,13 @@ use crate::check_ast::Checker;
 use crate::checks::{Check, CheckCode, CheckKind};
 
 fn is_sys(checker: &Checker, expr: &Expr, target: &str) -> bool {
-    match_module_member(expr, &format!("sys.{target}"), &checker.from_imports)
+    match_module_member(
+        expr,
+        "sys",
+        target,
+        &checker.from_imports,
+        &checker.import_aliases,
+    )
 }
 
 /// YTT101, YTT102, YTT301, YTT303
@@ -181,7 +187,13 @@ pub fn compare(checker: &mut Checker, left: &Expr, ops: &[Cmpop], comparators: &
 
 /// YTT202
 pub fn name_or_attribute(checker: &mut Checker, expr: &Expr) {
-    if match_module_member(expr, "six.PY3", &checker.from_imports) {
+    if match_module_member(
+        expr,
+        "six",
+        "PY3",
+        &checker.from_imports,
+        &checker.import_aliases,
+    ) {
         checker.add_check(Check::new(
             CheckKind::SixPY3Referenced,
             Range::from_located(expr),

src/flake8_annotations/plugins.rs

@@ -49,10 +49,13 @@ fn is_none_returning(body: &[Stmt]) -> bool {
 }
 
 /// ANN401
-fn check_dynamically_typed(checker: &mut Checker, annotation: &Expr, name: &str) {
-    if checker.match_typing_module(annotation, "Any") {
+fn check_dynamically_typed<F>(checker: &mut Checker, annotation: &Expr, func: F)
+where
+    F: FnOnce() -> String,
+{
+    if checker.match_typing_expr(annotation, "Any") {
         checker.add_check(Check::new(
-            CheckKind::DynamicallyTypedExpression(name.to_string()),
+            CheckKind::DynamicallyTypedExpression(func()),
             Range::from_located(annotation),
         ));
     };
@@ -100,7 +103,7 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
             {
                 if let Some(expr) = &arg.node.annotation {
                     if checker.settings.enabled.contains(&CheckCode::ANN401) {
-                        check_dynamically_typed(checker, expr, &arg.node.arg);
+                        check_dynamically_typed(checker, expr, || arg.node.arg.to_string());
                     };
                 } else {
                     if !(checker.settings.flake8_annotations.suppress_dummy_args
@@ -122,7 +125,7 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
                     if !checker.settings.flake8_annotations.allow_star_arg_any {
                         if checker.settings.enabled.contains(&CheckCode::ANN401) {
                             let name = arg.node.arg.to_string();
-                            check_dynamically_typed(checker, expr, &format!("*{name}"));
+                            check_dynamically_typed(checker, expr, || format!("*{name}"));
                         }
                     }
                 } else {
@@ -145,7 +148,7 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
                     if !checker.settings.flake8_annotations.allow_star_arg_any {
                         if checker.settings.enabled.contains(&CheckCode::ANN401) {
                             let name = arg.node.arg.to_string();
-                            check_dynamically_typed(checker, expr, &format!("**{name}"));
+                            check_dynamically_typed(checker, expr, || format!("**{name}"));
                         }
                     }
                 } else {
@@ -165,7 +168,7 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
             // ANN201, ANN202, ANN401
             if let Some(expr) = &returns {
                 if checker.settings.enabled.contains(&CheckCode::ANN401) {
-                    check_dynamically_typed(checker, expr, name);
+                    check_dynamically_typed(checker, expr, || name.to_string());
                 };
             } else {
                 // Allow omission of return annotation in `__init__` functions, if the function
@@ -215,7 +218,7 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
                 if let Some(annotation) = &arg.node.annotation {
                     has_any_typed_arg = true;
                     if checker.settings.enabled.contains(&CheckCode::ANN401) {
-                        check_dynamically_typed(checker, annotation, &arg.node.arg);
+                        check_dynamically_typed(checker, annotation, || arg.node.arg.to_string());
                     }
                 } else {
                     if !(checker.settings.flake8_annotations.suppress_dummy_args
@@ -238,7 +241,7 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
                     if !checker.settings.flake8_annotations.allow_star_arg_any {
                         if checker.settings.enabled.contains(&CheckCode::ANN401) {
                             let name = arg.node.arg.to_string();
-                            check_dynamically_typed(checker, expr, &format!("*{name}"));
+                            check_dynamically_typed(checker, expr, || format!("*{name}"));
                         }
                     }
                 } else {
@@ -262,7 +265,7 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
                     if !checker.settings.flake8_annotations.allow_star_arg_any {
                         if checker.settings.enabled.contains(&CheckCode::ANN401) {
                             let name = arg.node.arg.to_string();
-                            check_dynamically_typed(checker, expr, &format!("**{name}"));
+                            check_dynamically_typed(checker, expr, || format!("**{name}"));
                         }
                     }
                 } else {
@@ -305,7 +308,7 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
             // ANN201, ANN202
             if let Some(expr) = &returns {
                 if checker.settings.enabled.contains(&CheckCode::ANN401) {
-                    check_dynamically_typed(checker, expr, name);
+                    check_dynamically_typed(checker, expr, || name.to_string());
                 }
             } else {
                 // Allow omission of return annotation in `__init__` functions, if the function

src/flake8_bugbear/plugins/abstract_base_class.rs

@@ -0,0 +1,129 @@
+use fnv::{FnvHashMap, FnvHashSet};
+use rustpython_ast::{Constant, Expr, ExprKind, Keyword, Stmt, StmtKind};
+
+use crate::ast::helpers::match_module_member;
+use crate::ast::types::Range;
+use crate::check_ast::Checker;
+use crate::checks::{Check, CheckCode, CheckKind};
+
+fn is_abc_class(
+    bases: &[Expr],
+    keywords: &[Keyword],
+    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    import_aliases: &FnvHashMap<&str, &str>,
+) -> bool {
+    keywords.iter().any(|keyword| {
+        keyword
+            .node
+            .arg
+            .as_ref()
+            .map(|a| a == "metaclass")
+            .unwrap_or(false)
+            && match_module_member(
+                &keyword.node.value,
+                "abc",
+                "ABCMeta",
+                from_imports,
+                import_aliases,
+            )
+    }) || bases
+        .iter()
+        .any(|base| match_module_member(base, "abc", "ABC", from_imports, import_aliases))
+}
+
+fn is_empty_body(body: &[Stmt]) -> bool {
+    body.iter().all(|stmt| match &stmt.node {
+        StmtKind::Pass => true,
+        StmtKind::Expr { value } => match &value.node {
+            ExprKind::Constant { value, .. } => {
+                matches!(value, Constant::Str(..) | Constant::Ellipsis)
+            }
+            _ => false,
+        },
+        _ => false,
+    })
+}
+
+fn is_abstractmethod(
+    expr: &Expr,
+    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    import_aliases: &FnvHashMap<&str, &str>,
+) -> bool {
+    match_module_member(expr, "abc", "abstractmethod", from_imports, import_aliases)
+}
+
+fn is_overload(
+    expr: &Expr,
+    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    import_aliases: &FnvHashMap<&str, &str>,
+) -> bool {
+    match_module_member(expr, "typing", "overload", from_imports, import_aliases)
+}
+
+pub fn abstract_base_class(
+    checker: &mut Checker,
+    stmt: &Stmt,
+    name: &str,
+    bases: &[Expr],
+    keywords: &[Keyword],
+    body: &[Stmt],
+) {
+    if bases.len() + keywords.len() == 1
+        && is_abc_class(
+            bases,
+            keywords,
+            &checker.from_imports,
+            &checker.import_aliases,
+        )
+    {
+        let mut has_abstract_method = false;
+        for stmt in body {
+            // https://github.com/PyCQA/flake8-bugbear/issues/293
+            // Ignore abc's that declares a class attribute that must be set
+            if let StmtKind::AnnAssign { .. } | StmtKind::Assign { .. } = &stmt.node {
+                has_abstract_method = true;
+                continue;
+            }
+
+            if let StmtKind::FunctionDef {
+                decorator_list,
+                body,
+                ..
+            }
+            | StmtKind::AsyncFunctionDef {
+                decorator_list,
+                body,
+                ..
+            } = &stmt.node
+            {
+                let has_abstract_decorator = decorator_list
+                    .iter()
+                    .any(|d| is_abstractmethod(d, &checker.from_imports, &checker.import_aliases));
+
+                has_abstract_method |= has_abstract_decorator;
+
+                if checker.settings.enabled.contains(&CheckCode::B027) {
+                    if !has_abstract_decorator
+                        && is_empty_body(body)
+                        && !decorator_list
+                            .iter()
+                            .any(|d| is_overload(d, &checker.from_imports, &checker.import_aliases))
+                    {
+                        checker.add_check(Check::new(
+                            CheckKind::EmptyMethodWithoutAbstractDecorator(name.to_string()),
+                            Range::from_located(stmt),
+                        ));
+                    }
+                }
+            }
+        }
+        if checker.settings.enabled.contains(&CheckCode::B024) {
+            if !has_abstract_method {
+                checker.add_check(Check::new(
+                    CheckKind::AbstractBaseClassWithoutAbstractMethod(name.to_string()),
+                    Range::from_located(stmt),
+                ));
+            }
+        }
+    }
+}

src/flake8_bugbear/plugins/assert_raises_exception.rs

@@ -10,10 +10,10 @@ pub fn assert_raises_exception(checker: &mut Checker, stmt: &Stmt, items: &[With
     if let Some(item) = items.first() {
         let item_context = &item.context_expr;
         if let ExprKind::Call { func, args, .. } = &item_context.node {
-            if match_name_or_attr(func, "assertRaises")
-                && args.len() == 1
-                && match_name_or_attr(args.first().unwrap(), "Exception")
+            if args.len() == 1
                 && item.optional_vars.is_none()
+                && match_name_or_attr(func, "assertRaises")
+                && match_name_or_attr(args.first().unwrap(), "Exception")
             {
                 checker.add_check(Check::new(
                     CheckKind::NoAssertRaisesException,

src/flake8_bugbear/plugins/cached_instance_method.rs

@@ -1,13 +1,14 @@
 use rustpython_ast::{Expr, ExprKind};
 
-use crate::ast::helpers::{compose_call_path, match_module_member};
+use crate::ast::helpers::{collect_call_paths, dealias_call_path, match_call_path};
 use crate::ast::types::{Range, ScopeKind};
 use crate::check_ast::Checker;
 use crate::checks::{Check, CheckKind};
 
 fn is_cache_func(checker: &Checker, expr: &Expr) -> bool {
-    match_module_member(expr, "functools.lru_cache", &checker.from_imports)
-        || match_module_member(expr, "functools.cache", &checker.from_imports)
+    let call_path = dealias_call_path(collect_call_paths(expr), &checker.import_aliases);
+    match_call_path(&call_path, "functools", "lru_cache", &checker.from_imports)
+        || match_call_path(&call_path, "functools", "cache", &checker.from_imports)
 }
 
 /// B019
@@ -16,8 +17,8 @@ pub fn cached_instance_method(checker: &mut Checker, decorator_list: &[Expr]) {
         for decorator in decorator_list {
             // TODO(charlie): This should take into account `classmethod-decorators` and
             // `staticmethod-decorators`.
-            if let Some(decorator_path) = compose_call_path(decorator) {
-                if decorator_path == "classmethod" || decorator_path == "staticmethod" {
+            if let ExprKind::Name { id, .. } = &decorator.node {
+                if id == "classmethod" || id == "staticmethod" {
                     return;
                 }
             }

src/flake8_bugbear/plugins/duplicate_exceptions.rs

@@ -21,20 +21,21 @@ fn type_pattern(elts: Vec<&Expr>) -> Expr {
     )
 }
 
-pub fn duplicate_handler_exceptions(
+fn duplicate_handler_exceptions<'a>(
     checker: &mut Checker,
-    expr: &Expr,
-    elts: &[Expr],
-) -> BTreeSet<String> {
-    let mut seen: BTreeSet<String> = Default::default();
-    let mut duplicates: BTreeSet<String> = Default::default();
+    expr: &'a Expr,
+    elts: &'a [Expr],
+) -> BTreeSet<Vec<&'a str>> {
+    let mut seen: BTreeSet<Vec<&str>> = Default::default();
+    let mut duplicates: BTreeSet<Vec<&str>> = Default::default();
     let mut unique_elts: Vec<&Expr> = Default::default();
     for type_ in elts {
-        if let Some(name) = helpers::compose_call_path(type_) {
-            if seen.contains(&name) {
-                duplicates.insert(name);
+        let call_path = helpers::collect_call_paths(type_);
+        if !call_path.is_empty() {
+            if seen.contains(&call_path) {
+                duplicates.insert(call_path);
             } else {
-                seen.insert(name);
+                seen.insert(call_path);
                 unique_elts.push(type_);
             }
         }
@@ -45,7 +46,11 @@ pub fn duplicate_handler_exceptions(
         if !duplicates.is_empty() {
             let mut check = Check::new(
                 CheckKind::DuplicateHandlerException(
-                    duplicates.into_iter().sorted().collect::<Vec<String>>(),
+                    duplicates
+                        .into_iter()
+                        .map(|call_path| call_path.join("."))
+                        .sorted()
+                        .collect::<Vec<String>>(),
                 ),
                 Range::from_located(expr),
             );
@@ -70,19 +75,20 @@ pub fn duplicate_handler_exceptions(
 }
 
 pub fn duplicate_exceptions(checker: &mut Checker, stmt: &Stmt, handlers: &[Excepthandler]) {
-    let mut seen: BTreeSet<String> = Default::default();
-    let mut duplicates: BTreeSet<String> = Default::default();
+    let mut seen: BTreeSet<Vec<&str>> = Default::default();
+    let mut duplicates: BTreeSet<Vec<&str>> = Default::default();
     for handler in handlers {
         match &handler.node {
             ExcepthandlerKind::ExceptHandler { type_, .. } => {
                 if let Some(type_) = type_ {
                     match &type_.node {
                         ExprKind::Attribute { .. } | ExprKind::Name { .. } => {
-                            if let Some(name) = helpers::compose_call_path(type_) {
-                                if seen.contains(&name) {
-                                    duplicates.insert(name);
+                            let call_path = helpers::collect_call_paths(type_);
+                            if !call_path.is_empty() {
+                                if seen.contains(&call_path) {
+                                    duplicates.insert(call_path);
                                 } else {
-                                    seen.insert(name);
+                                    seen.insert(call_path);
                                 }
                             }
                         }
@@ -105,7 +111,7 @@ pub fn duplicate_exceptions(checker: &mut Checker, stmt: &Stmt, handlers: &[Exce
     if checker.settings.enabled.contains(&CheckCode::B025) {
         for duplicate in duplicates.into_iter().sorted() {
             checker.add_check(Check::new(
-                CheckKind::DuplicateTryBlockException(duplicate),
+                CheckKind::DuplicateTryBlockException(duplicate.join(".")),
                 Range::from_located(stmt),
             ));
         }

src/flake8_bugbear/plugins/function_call_argument_default.rs

@@ -1,7 +1,9 @@
 use fnv::{FnvHashMap, FnvHashSet};
 use rustpython_ast::{Arguments, Constant, Expr, ExprKind};
 
-use crate::ast::helpers::{compose_call_path, match_call_path};
+use crate::ast::helpers::{
+    collect_call_paths, compose_call_path, dealias_call_path, match_call_path,
+};
 use crate::ast::types::Range;
 use crate::ast::visitor;
 use crate::ast::visitor::Visitor;
@@ -9,35 +11,34 @@ use crate::check_ast::Checker;
 use crate::checks::{Check, CheckKind};
 use crate::flake8_bugbear::plugins::mutable_argument_default::is_mutable_func;
 
-const IMMUTABLE_FUNCS: [&str; 7] = [
-    "tuple",
-    "frozenset",
-    "operator.attrgetter",
-    "operator.itemgetter",
-    "operator.methodcaller",
-    "types.MappingProxyType",
-    "re.compile",
+const IMMUTABLE_FUNCS: [(&str, &str); 7] = [
+    ("", "tuple"),
+    ("", "frozenset"),
+    ("operator", "attrgetter"),
+    ("operator", "itemgetter"),
+    ("operator", "methodcaller"),
+    ("types", "MappingProxyType"),
+    ("re", "compile"),
 ];
 
 fn is_immutable_func(
     expr: &Expr,
-    extend_immutable_calls: &[&str],
+    extend_immutable_calls: &[(&str, &str)],
     from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    import_aliases: &FnvHashMap<&str, &str>,
 ) -> bool {
-    compose_call_path(expr)
-        .map(|call_path| {
-            IMMUTABLE_FUNCS
-                .iter()
-                .chain(extend_immutable_calls)
-                .any(|target| match_call_path(&call_path, target, from_imports))
-        })
-        .unwrap_or(false)
+    let call_path = dealias_call_path(collect_call_paths(expr), import_aliases);
+    IMMUTABLE_FUNCS
+        .iter()
+        .chain(extend_immutable_calls)
+        .any(|(module, member)| match_call_path(&call_path, module, member, from_imports))
 }
 
 struct ArgumentDefaultVisitor<'a> {
     checks: Vec<(CheckKind, Range)>,
-    extend_immutable_calls: &'a [&'a str],
+    extend_immutable_calls: &'a [(&'a str, &'a str)],
     from_imports: &'a FnvHashMap<&'a str, FnvHashSet<&'a str>>,
+    import_aliases: &'a FnvHashMap<&'a str, &'a str>,
 }
 
 impl<'a, 'b> Visitor<'b> for ArgumentDefaultVisitor<'b>
@@ -47,8 +48,13 @@ where
     fn visit_expr(&mut self, expr: &'b Expr) {
         match &expr.node {
             ExprKind::Call { func, args, .. } => {
-                if !is_mutable_func(func, self.from_imports)
-                    && !is_immutable_func(func, self.extend_immutable_calls, self.from_imports)
+                if !is_mutable_func(func, self.from_imports, self.import_aliases)
+                    && !is_immutable_func(
+                        func,
+                        self.extend_immutable_calls,
+                        self.from_imports,
+                        self.import_aliases,
+                    )
                     && !is_nan_or_infinity(func, args)
                 {
                     self.checks.push((
@@ -92,17 +98,26 @@ fn is_nan_or_infinity(expr: &Expr, args: &[Expr]) -> bool {
 
 /// B008
 pub fn function_call_argument_default(checker: &mut Checker, arguments: &Arguments) {
-    let extend_immutable_cells: Vec<&str> = checker
+    // Map immutable calls to (module, member) format.
+    let extend_immutable_cells: Vec<(&str, &str)> = checker
         .settings
         .flake8_bugbear
         .extend_immutable_calls
         .iter()
-        .map(|s| s.as_str())
+        .map(|s| {
+            let s = s.as_str();
+            if let Some(index) = s.rfind('.') {
+                (&s[..index], &s[index + 1..])
+            } else {
+                ("", s)
+            }
+        })
         .collect();
     let mut visitor = ArgumentDefaultVisitor {
         checks: vec![],
         extend_immutable_calls: &extend_immutable_cells,
         from_imports: &checker.from_imports,
+        import_aliases: &checker.import_aliases,
     };
     for expr in arguments
         .defaults

src/flake8_bugbear/plugins/loop_variable_overrides_iterator.rs

@@ -0,0 +1,64 @@
+use fnv::FnvHashMap;
+use rustpython_ast::{Expr, ExprKind};
+
+use crate::ast::types::Range;
+use crate::ast::visitor;
+use crate::ast::visitor::Visitor;
+use crate::check_ast::Checker;
+use crate::checks::{Check, CheckKind};
+
+#[derive(Default)]
+struct NameFinder<'a> {
+    names: FnvHashMap<&'a str, &'a Expr>,
+}
+
+impl<'a, 'b> Visitor<'b> for NameFinder<'a>
+where
+    'b: 'a,
+{
+    fn visit_expr(&mut self, expr: &'b Expr) {
+        match &expr.node {
+            ExprKind::Name { id, .. } => {
+                self.names.insert(id, expr);
+            }
+            ExprKind::ListComp { generators, .. }
+            | ExprKind::DictComp { generators, .. }
+            | ExprKind::SetComp { generators, .. }
+            | ExprKind::GeneratorExp { generators, .. } => {
+                for comp in generators {
+                    self.visit_expr(&comp.iter);
+                }
+            }
+            ExprKind::Lambda { args, body } => {
+                visitor::walk_expr(self, body);
+                for arg in args.args.iter() {
+                    self.names.remove(arg.node.arg.as_str());
+                }
+            }
+            _ => visitor::walk_expr(self, expr),
+        }
+    }
+}
+
+/// B020
+pub fn loop_variable_overrides_iterator(checker: &mut Checker, target: &Expr, iter: &Expr) {
+    let target_names = {
+        let mut target_finder = NameFinder::default();
+        target_finder.visit_expr(target);
+        target_finder.names
+    };
+    let iter_names = {
+        let mut iter_finder = NameFinder::default();
+        iter_finder.visit_expr(iter);
+        iter_finder.names
+    };
+
+    for (name, expr) in target_names {
+        if iter_names.contains_key(name) {
+            checker.add_check(Check::new(
+                CheckKind::LoopVariableOverridesIterator(name.to_string()),
+                Range::from_located(expr),
+            ));
+        }
+    }
+}

src/flake8_bugbear/plugins/mod.rs

@@ -1,13 +1,15 @@
+pub use abstract_base_class::abstract_base_class;
 pub use assert_false::assert_false;
 pub use assert_raises_exception::assert_raises_exception;
 pub use assignment_to_os_environ::assignment_to_os_environ;
 pub use cached_instance_method::cached_instance_method;
 pub use cannot_raise_literal::cannot_raise_literal;
-pub use duplicate_exceptions::{duplicate_exceptions, duplicate_handler_exceptions};
+pub use duplicate_exceptions::duplicate_exceptions;
 pub use f_string_docstring::f_string_docstring;
 pub use function_call_argument_default::function_call_argument_default;
 pub use getattr_with_constant::getattr_with_constant;
 pub use jump_statement_in_finally::jump_statement_in_finally;
+pub use loop_variable_overrides_iterator::loop_variable_overrides_iterator;
 pub use mutable_argument_default::mutable_argument_default;
 pub use redundant_tuple_in_exception_handler::redundant_tuple_in_exception_handler;
 pub use setattr_with_constant::setattr_with_constant;
@@ -17,8 +19,10 @@ pub use unary_prefix_increment::unary_prefix_increment;
 pub use unreliable_callable_check::unreliable_callable_check;
 pub use unused_loop_control_variable::unused_loop_control_variable;
 pub use useless_comparison::useless_comparison;
+pub use useless_contextlib_suppress::useless_contextlib_suppress;
 pub use useless_expression::useless_expression;
 
+mod abstract_base_class;
 mod assert_false;
 mod assert_raises_exception;
 mod assignment_to_os_environ;
@@ -29,6 +33,7 @@ mod f_string_docstring;
 mod function_call_argument_default;
 mod getattr_with_constant;
 mod jump_statement_in_finally;
+mod loop_variable_overrides_iterator;
 mod mutable_argument_default;
 mod redundant_tuple_in_exception_handler;
 mod setattr_with_constant;
@@ -38,4 +43,5 @@ mod unary_prefix_increment;
 mod unreliable_callable_check;
 mod unused_loop_control_variable;
 mod useless_comparison;
+mod useless_contextlib_suppress;
 mod useless_expression;

src/flake8_bugbear/plugins/mutable_argument_default.rs

@@ -1,29 +1,30 @@
 use fnv::{FnvHashMap, FnvHashSet};
 use rustpython_ast::{Arguments, Expr, ExprKind};
 
-use crate::ast::helpers::{compose_call_path, match_call_path};
+use crate::ast::helpers::{collect_call_paths, dealias_call_path, match_call_path};
 use crate::ast::types::Range;
 use crate::check_ast::Checker;
 use crate::checks::{Check, CheckKind};
 
-const MUTABLE_FUNCS: [&str; 7] = [
-    "dict",
-    "list",
-    "set",
-    "collections.Counter",
-    "collections.OrderedDict",
-    "collections.defaultdict",
-    "collections.deque",
+const MUTABLE_FUNCS: [(&str, &str); 7] = [
+    ("", "dict"),
+    ("", "list"),
+    ("", "set"),
+    ("collections", "Counter"),
+    ("collections", "OrderedDict"),
+    ("collections", "defaultdict"),
+    ("collections", "deque"),
 ];
 
-pub fn is_mutable_func(expr: &Expr, from_imports: &FnvHashMap<&str, FnvHashSet<&str>>) -> bool {
-    compose_call_path(expr)
-        .map(|call_path| {
-            MUTABLE_FUNCS
-                .iter()
-                .any(|target| match_call_path(&call_path, target, from_imports))
-        })
-        .unwrap_or(false)
+pub fn is_mutable_func(
+    expr: &Expr,
+    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    import_aliases: &FnvHashMap<&str, &str>,
+) -> bool {
+    let call_path = dealias_call_path(collect_call_paths(expr), import_aliases);
+    MUTABLE_FUNCS
+        .iter()
+        .any(|(module, member)| match_call_path(&call_path, module, member, from_imports))
 }
 
 /// B006
@@ -46,7 +47,7 @@ pub fn mutable_argument_default(checker: &mut Checker, arguments: &Arguments) {
                 ));
             }
             ExprKind::Call { func, .. } => {
-                if is_mutable_func(func, &checker.from_imports) {
+                if is_mutable_func(func, &checker.from_imports, &checker.import_aliases) {
                     checker.add_check(Check::new(
                         CheckKind::MutableArgumentDefault,
                         Range::from_located(expr),

src/flake8_bugbear/plugins/useless_contextlib_suppress.rs

@@ -0,0 +1,22 @@
+use rustpython_ast::Expr;
+
+use crate::ast::helpers::{collect_call_paths, match_call_path};
+use crate::ast::types::Range;
+use crate::check_ast::Checker;
+use crate::checks::{Check, CheckKind};
+
+/// B005
+pub fn useless_contextlib_suppress(checker: &mut Checker, expr: &Expr, args: &[Expr]) {
+    if match_call_path(
+        &collect_call_paths(expr),
+        "contextlib",
+        "suppress",
+        &checker.from_imports,
+    ) && args.is_empty()
+    {
+        checker.add_check(Check::new(
+            CheckKind::UselessContextlibSuppress,
+            Range::from_located(expr),
+        ));
+    }
+}

src/fs.rs

@@ -1,11 +1,11 @@
 use std::borrow::Cow;
-use std::collections::BTreeSet;
 use std::fs::File;
 use std::io::{BufReader, Read};
 use std::ops::Deref;
 use std::path::{Path, PathBuf};
 
 use anyhow::{anyhow, Result};
+use fnv::FnvHashSet;
 use log::debug;
 use path_absolutize::{path_dedot, Absolutize};
 use walkdir::{DirEntry, WalkDir};
@@ -121,7 +121,7 @@ pub fn iter_python_files<'a>(
 pub(crate) fn ignores_from_path<'a>(
     path: &Path,
     pattern_code_pairs: &'a [PerFileIgnore],
-) -> Result<BTreeSet<&'a CheckCode>> {
+) -> Result<FnvHashSet<&'a CheckCode>> {
     let (file_path, file_basename) = extract_path_names(path)?;
     Ok(pattern_code_pairs
         .iter()

src/isort/categorize.rs

@@ -1,9 +1,7 @@
-use std::collections::{BTreeMap, BTreeSet};
+use std::collections::BTreeSet;
 use std::fs;
 use std::path::PathBuf;
 
-use once_cell::sync::Lazy;
-
 use crate::python::sys::KNOWN_STANDARD_LIBRARY;
 
 #[derive(Debug, PartialOrd, Ord, PartialEq, Eq, Clone)]
@@ -31,8 +29,8 @@ pub fn categorize(
         ImportType::ThirdParty
     } else if extra_standard_library.contains(module_base) {
         ImportType::StandardLibrary
-    } else if let Some(import_type) = STATIC_CLASSIFICATIONS.get(module_base) {
-        import_type.clone()
+    } else if module_base == "__future__" {
+        ImportType::Future
     } else if KNOWN_STANDARD_LIBRARY.contains(module_base) {
         ImportType::StandardLibrary
     } else if find_local(src, module_base) {
@@ -42,14 +40,6 @@ pub fn categorize(
     }
 }
 
-static STATIC_CLASSIFICATIONS: Lazy<BTreeMap<&'static str, ImportType>> = Lazy::new(|| {
-    BTreeMap::from([
-        ("__future__", ImportType::Future),
-        // Relative imports (e.g., `from . import module`).
-        ("", ImportType::FirstParty),
-    ])
-});
-
 fn find_local(paths: &[PathBuf], base: &str) -> bool {
     for path in paths {
         if let Ok(metadata) = fs::metadata(path.join(base)) {

src/isort/mod.rs

@@ -1,6 +1,7 @@
 use std::collections::{BTreeMap, BTreeSet};
 use std::path::PathBuf;
 
+use fnv::FnvHashSet;
 use itertools::Itertools;
 use ropey::RopeBuilder;
 use rustpython_ast::{Stmt, StmtKind};
@@ -36,15 +37,25 @@ fn normalize_imports<'a>(imports: &'a [&'a Stmt]) -> ImportBlock<'a> {
                 names,
                 level,
             } => {
-                let targets = block
-                    .import_from
-                    .entry(ImportFromData { module, level })
-                    .or_default();
                 for name in names {
-                    targets.insert(AliasData {
-                        name: &name.node.name,
-                        asname: &name.node.asname,
-                    });
+                    if name.node.asname.is_none() {
+                        block
+                            .import_from
+                            .entry(ImportFromData { module, level })
+                            .or_default()
+                            .insert(AliasData {
+                                name: &name.node.name,
+                                asname: &name.node.asname,
+                            });
+                    } else {
+                        block.import_from_as.insert((
+                            ImportFromData { module, level },
+                            AliasData {
+                                name: &name.node.name,
+                                asname: &name.node.asname,
+                            },
+                        ));
+                    }
                 }
             }
             _ => unreachable!("Expected StmtKind::Import | StmtKind::ImportFrom"),
@@ -77,7 +88,7 @@ fn categorize_imports<'a>(
             .import
             .insert(alias);
     }
-    // Categorize `StmtKind::ImportFrom`.
+    // Categorize `StmtKind::ImportFrom` (without re-export).
     for (import_from, aliases) in block.import_from {
         let classification = categorize(
             &import_from.module_base(),
@@ -93,36 +104,74 @@ fn categorize_imports<'a>(
             .import_from
             .insert(import_from, aliases);
     }
+    // Categorize `StmtKind::ImportFrom` (with re-export).
+    for (import_from, alias) in block.import_from_as {
+        let classification = categorize(
+            &import_from.module_base(),
+            import_from.level,
+            src,
+            known_first_party,
+            known_third_party,
+            extra_standard_library,
+        );
+        block_by_type
+            .entry(classification)
+            .or_default()
+            .import_from_as
+            .insert((import_from, alias));
+    }
     block_by_type
 }
 
 fn sort_imports(block: ImportBlock) -> OrderedImportBlock {
     let mut ordered: OrderedImportBlock = Default::default();
+
     // Sort `StmtKind::Import`.
-    for import in block
-        .import
-        .into_iter()
-        .sorted_by_cached_key(|alias| module_key(alias.name))
-    {
-        ordered.import.push(import);
-    }
+    ordered.import.extend(
+        block
+            .import
+            .into_iter()
+            .sorted_by_cached_key(|alias| module_key(alias.name, alias.asname)),
+    );
+
     // Sort `StmtKind::ImportFrom`.
-    for (import_from, aliases) in
+    ordered.import_from.extend(
+        // Include all non-re-exports.
         block
             .import_from
             .into_iter()
-            .sorted_by_cached_key(|(import_from, _)| {
-                import_from.module.as_ref().map(|module| module_key(module))
+            .chain(
+                // Include all re-exports.
+                block
+                    .import_from_as
+                    .into_iter()
+                    .map(|(import_from, alias)| (import_from, FnvHashSet::from_iter([alias]))),
+            )
+            .map(|(import_from, aliases)| {
+                // Within each `StmtKind::ImportFrom`, sort the members.
+                (
+                    import_from,
+                    aliases
+                        .into_iter()
+                        .sorted_by_cached_key(|alias| member_key(alias.name, alias.asname))
+                        .collect::<Vec<AliasData>>(),
+                )
             })
-    {
-        ordered.import_from.push((
-            import_from,
-            aliases
-                .into_iter()
-                .sorted_by_cached_key(|alias| member_key(alias.name))
-                .collect(),
-        ));
-    }
+            .sorted_by_cached_key(|(import_from, aliases)| {
+                // Sort each `StmtKind::ImportFrom` by module key, breaking ties based on
+                // members.
+                (
+                    import_from
+                        .module
+                        .as_ref()
+                        .map(|module| module_key(module, &None)),
+                    aliases
+                        .first()
+                        .map(|alias| member_key(alias.name, alias.asname)),
+                )
+            }),
+    );
+
     ordered
 }
 
@@ -252,6 +301,7 @@ mod tests {
     #[test_case(Path::new("separate_local_folder_imports.py"))]
     #[test_case(Path::new("separate_third_party_imports.py"))]
     #[test_case(Path::new("skip.py"))]
+    #[test_case(Path::new("sort_similar_imports.py"))]
     #[test_case(Path::new("trailing_suffix.py"))]
     fn isort(path: &Path) -> Result<()> {
         let snapshot = format!("{}", path.to_string_lossy());

src/isort/snapshots/ruff__isort__tests__sort_similar_imports.py.snap

@@ -0,0 +1,22 @@
+---
+source: src/isort/mod.rs
+expression: checks
+---
+- kind: UnsortedImports
+  location:
+    row: 1
+    column: 0
+  end_location:
+    row: 27
+    column: 0
+  fix:
+    patch:
+      content: "import A\nimport a\nimport B\nimport b\nimport x\nimport x as A\nimport x as Y\nimport x as a\nimport x as y\nfrom a import BAD as DEF\nfrom a import B, b\nfrom a import B as A\nfrom a import B as Abc\nfrom a import B as DEF\nfrom a import Boo as DEF\nfrom a import b as a\nfrom a import b as c\nfrom a import b as d\nfrom a import b as x\nfrom a import b as y\nfrom b import C, c\nfrom b import c as d\n"
+      location:
+        row: 1
+        column: 0
+      end_location:
+        row: 27
+        column: 0
+    applied: false
+

src/isort/sorting.rs

@@ -8,16 +8,22 @@ pub enum Prefix {
     Variables,
 }
 
-pub fn module_key(module_name: &str) -> String {
-    module_name.to_lowercase()
+pub fn module_key<'a>(
+    name: &'a str,
+    asname: &'a Option<String>,
+) -> (String, &'a str, &'a Option<String>) {
+    (name.to_lowercase(), name, asname)
 }
 
-pub fn member_key(member_name: &str) -> (Prefix, String) {
+pub fn member_key<'a>(
+    name: &'a str,
+    asname: &'a Option<String>,
+) -> (Prefix, String, &'a Option<String>) {
     (
-        if member_name.len() > 1 && string::is_upper(member_name) {
+        if name.len() > 1 && string::is_upper(name) {
             // Ex) `CONSTANT`
             Prefix::Constants
-        } else if member_name
+        } else if name
             .chars()
             .next()
             .map(|char| char.is_uppercase())
@@ -29,6 +35,7 @@ pub fn member_key(member_name: &str) -> (Prefix, String) {
             // Ex) `variable`
             Prefix::Variables
         },
-        member_name.to_lowercase(),
+        name.to_lowercase(),
+        asname,
     )
 }

src/isort/types.rs

@@ -1,4 +1,4 @@
-use std::collections::{BTreeMap, BTreeSet};
+use fnv::{FnvHashMap, FnvHashSet};
 
 #[derive(Debug, Hash, Ord, PartialOrd, Eq, PartialEq)]
 pub struct ImportFromData<'a> {
@@ -48,16 +48,19 @@ impl Importable for ImportFromData<'_> {
 
 #[derive(Debug, Default)]
 pub struct ImportBlock<'a> {
-    // Map from (module, level) to `AliasData`.
-    pub import_from: BTreeMap<ImportFromData<'a>, BTreeSet<AliasData<'a>>>,
-    // Set of (name, asname).
-    pub import: BTreeSet<AliasData<'a>>,
+    // Set of (name, asname), used to track regular imports.
+    // Ex) `import module`
+    pub import: FnvHashSet<AliasData<'a>>,
+    // Map from (module, level) to `AliasData`, used to track 'from' imports.
+    // Ex) `from module import member`
+    pub import_from: FnvHashMap<ImportFromData<'a>, FnvHashSet<AliasData<'a>>>,
+    // Set of (module, level, name, asname), used to track re-exported 'from' imports.
+    // Ex) `from module import member as member`
+    pub import_from_as: FnvHashSet<(ImportFromData<'a>, AliasData<'a>)>,
 }
 
 #[derive(Debug, Default)]
 pub struct OrderedImportBlock<'a> {
-    // Map from (module, level) to `AliasData`.
-    pub import_from: Vec<(ImportFromData<'a>, Vec<AliasData<'a>>)>,
-    // Set of (name, asname).
     pub import: Vec<AliasData<'a>>,
+    pub import_from: Vec<(ImportFromData<'a>, Vec<AliasData<'a>>)>,
 }

src/lib.rs

@@ -52,6 +52,8 @@ mod pyupgrade;
 mod rules;
 pub mod settings;
 pub mod source_code_locator;
+#[cfg(feature = "update-informer")]
+pub mod updates;
 pub mod visibility;
 
 /// Run Ruff over Python source code directly.

src/linter.rs

@@ -344,9 +344,13 @@ mod tests {
     #[test_case(CheckCode::B017, Path::new("B017.py"); "B017")]
     #[test_case(CheckCode::B018, Path::new("B018.py"); "B018")]
     #[test_case(CheckCode::B019, Path::new("B019.py"); "B019")]
+    #[test_case(CheckCode::B020, Path::new("B020.py"); "B020")]
     #[test_case(CheckCode::B021, Path::new("B021.py"); "B021")]
+    #[test_case(CheckCode::B022, Path::new("B022.py"); "B022")]
+    #[test_case(CheckCode::B024, Path::new("B024.py"); "B024")]
     #[test_case(CheckCode::B025, Path::new("B025.py"); "B025")]
     #[test_case(CheckCode::B026, Path::new("B026.py"); "B026")]
+    #[test_case(CheckCode::B027, Path::new("B027.py"); "B027")]
     #[test_case(CheckCode::C400, Path::new("C400.py"); "C400")]
     #[test_case(CheckCode::C401, Path::new("C401.py"); "C401")]
     #[test_case(CheckCode::C402, Path::new("C402.py"); "C402")]
@@ -452,6 +456,8 @@ mod tests {
     #[test_case(CheckCode::F821, Path::new("F821_1.py"); "F821_1")]
     #[test_case(CheckCode::F821, Path::new("F821_2.py"); "F821_2")]
     #[test_case(CheckCode::F821, Path::new("F821_3.py"); "F821_3")]
+    #[test_case(CheckCode::F821, Path::new("F821_4.py"); "F821_4")]
+    #[test_case(CheckCode::F821, Path::new("F821_5.py"); "F821_5")]
     #[test_case(CheckCode::F822, Path::new("F822.py"); "F822")]
     #[test_case(CheckCode::F823, Path::new("F823.py"); "F823")]
     #[test_case(CheckCode::F831, Path::new("F831.py"); "F831")]

src/main.rs

@@ -17,6 +17,8 @@ use ::ruff::settings::configuration::Configuration;
 use ::ruff::settings::types::FilePattern;
 use ::ruff::settings::user::UserConfiguration;
 use ::ruff::settings::{pyproject, Settings};
+#[cfg(feature = "update-informer")]
+use ::ruff::updates;
 use anyhow::Result;
 use clap::Parser;
 use colored::Colorize;
@@ -26,11 +28,6 @@ use notify::{raw_watcher, RecursiveMode, Watcher};
 use rayon::prelude::*;
 use walkdir::DirEntry;
 
-#[cfg(feature = "update-informer")]
-const CARGO_PKG_NAME: &str = env!("CARGO_PKG_NAME");
-#[cfg(feature = "update-informer")]
-const CARGO_PKG_VERSION: &str = env!("CARGO_PKG_VERSION");
-
 /// Shim that calls par_iter except for wasm because there's no wasm support in
 /// rayon yet (there is a shim to be used for the web, but it requires js
 /// cooperation) Unfortunately, ParallelIterator does not implement Iterator so
@@ -45,30 +42,6 @@ fn par_iter<T: Sync>(iterable: &Vec<T>) -> impl Iterator<Item = &T> {
     iterable.iter()
 }
 
-#[cfg(feature = "update-informer")]
-fn check_for_updates() {
-    use update_informer::{registry, Check};
-
-    let informer = update_informer::new(registry::PyPI, CARGO_PKG_NAME, CARGO_PKG_VERSION);
-
-    if let Some(new_version) = informer.check_version().ok().flatten() {
-        let msg = format!(
-            "A new version of {pkg_name} is available: v{pkg_version} -> {new_version}",
-            pkg_name = CARGO_PKG_NAME.italic().cyan(),
-            pkg_version = CARGO_PKG_VERSION,
-            new_version = new_version.to_string().green()
-        );
-
-        let cmd = format!(
-            "Run to update: {cmd} {pkg_name}",
-            cmd = "pip3 install --upgrade".green(),
-            pkg_name = CARGO_PKG_NAME.green()
-        );
-
-        println!("\n{msg}\n{cmd}");
-    }
-}
-
 fn show_settings(
     configuration: Configuration,
     project_root: Option<PathBuf>,
@@ -292,6 +265,9 @@ fn inner_main() -> Result<ExitCode> {
     if !cli.extend_ignore.is_empty() {
         configuration.extend_ignore = cli.extend_ignore;
     }
+    if let Some(line_length) = cli.line_length {
+        configuration.line_length = line_length;
+    }
     if let Some(target_version) = cli.target_version {
         configuration.target_version = target_version;
     }
@@ -402,8 +378,8 @@ fn inner_main() -> Result<ExitCode> {
 
         // Check for updates if we're in a non-silent log level.
         #[cfg(feature = "update-informer")]
-        if !is_stdin && log_level >= LogLevel::Default {
-            check_for_updates();
+        if !is_stdin && log_level >= LogLevel::Default && atty::is(atty::Stream::Stdout) {
+            let _ = updates::check_for_updates();
         }
 
         if messages.iter().any(|message| !message.fixed) && !cli.exit_zero {

src/pep8_naming/checks.rs

@@ -1,11 +1,11 @@
 use rustpython_ast::{Arguments, Expr, ExprKind, Stmt};
 
-use crate::ast::types::{FunctionScope, Range, Scope, ScopeKind};
+use crate::ast::types::{Range, Scope, ScopeKind};
 use crate::checks::{Check, CheckKind};
 use crate::pep8_naming::helpers;
 use crate::pep8_naming::helpers::FunctionType;
 use crate::pep8_naming::settings::Settings;
-use crate::python::string;
+use crate::python::string::{self};
 
 /// N801
 pub fn invalid_class_name(class_def: &Stmt, name: &str) -> Option<Check> {
@@ -100,20 +100,6 @@ pub fn invalid_first_argument_name_for_method(
     None
 }
 
-/// N806
-pub fn non_lowercase_variable_in_function(scope: &Scope, expr: &Expr, name: &str) -> Option<Check> {
-    if !matches!(scope.kind, ScopeKind::Function(FunctionScope { .. })) {
-        return None;
-    }
-    if name.to_lowercase() != name {
-        return Some(Check::new(
-            CheckKind::NonLowercaseVariableInFunction(name.to_string()),
-            Range::from_located(expr),
-        ));
-    }
-    None
-}
-
 /// N807
 pub fn dunder_function_name(scope: &Scope, stmt: &Stmt, name: &str) -> Option<Check> {
     if matches!(scope.kind, ScopeKind::Class(_)) {
@@ -192,38 +178,6 @@ pub fn camelcase_imported_as_constant(
     None
 }
 
-/// N815
-pub fn mixed_case_variable_in_class_scope(scope: &Scope, expr: &Expr, name: &str) -> Option<Check> {
-    if !matches!(scope.kind, ScopeKind::Class(_)) {
-        return None;
-    }
-    if helpers::is_mixed_case(name) {
-        return Some(Check::new(
-            CheckKind::MixedCaseVariableInClassScope(name.to_string()),
-            Range::from_located(expr),
-        ));
-    }
-    None
-}
-
-/// N816
-pub fn mixed_case_variable_in_global_scope(
-    scope: &Scope,
-    expr: &Expr,
-    name: &str,
-) -> Option<Check> {
-    if !matches!(scope.kind, ScopeKind::Module) {
-        return None;
-    }
-    if helpers::is_mixed_case(name) {
-        return Some(Check::new(
-            CheckKind::MixedCaseVariableInGlobalScope(name.to_string()),
-            Range::from_located(expr),
-        ));
-    }
-    None
-}
-
 /// N817
 pub fn camelcase_imported_as_acronym(
     import_from: &Stmt,

src/pep8_naming/helpers.rs

@@ -1,7 +1,8 @@
+use fnv::{FnvHashMap, FnvHashSet};
 use itertools::Itertools;
-use rustpython_ast::{Expr, ExprKind};
+use rustpython_ast::{Expr, ExprKind, Stmt, StmtKind};
 
-use crate::ast::helpers::match_name_or_attr;
+use crate::ast::helpers::{collect_call_paths, match_call_path, match_name_or_attr};
 use crate::ast::types::{Scope, ScopeKind};
 use crate::pep8_naming::settings::Settings;
 use crate::python::string::{is_lower, is_upper};
@@ -78,6 +79,22 @@ pub fn is_acronym(name: &str, asname: &str) -> bool {
     name.chars().filter(|c| c.is_uppercase()).join("") == asname
 }
 
+pub fn is_namedtuple_assignment(
+    stmt: &Stmt,
+    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+) -> bool {
+    if let StmtKind::Assign { value, .. } = &stmt.node {
+        match_call_path(
+            &collect_call_paths(value),
+            "collections",
+            "namedtuple",
+            from_imports,
+        )
+    } else {
+        false
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use crate::pep8_naming::helpers::{is_acronym, is_camelcase, is_mixed_case};

src/pep8_naming/mod.rs

@@ -1,3 +1,4 @@
 pub mod checks;
 mod helpers;
+pub mod plugins;
 pub mod settings;

src/pep8_naming/plugins.rs

@@ -0,0 +1,58 @@
+use rustpython_ast::{Expr, Stmt};
+
+use crate::ast::types::Range;
+use crate::check_ast::Checker;
+use crate::checks::CheckKind;
+use crate::pep8_naming::helpers;
+use crate::Check;
+
+/// N806
+pub fn non_lowercase_variable_in_function(
+    checker: &mut Checker,
+    expr: &Expr,
+    stmt: &Stmt,
+    name: &str,
+) {
+    if name.to_lowercase() != name
+        && !helpers::is_namedtuple_assignment(stmt, &checker.from_imports)
+    {
+        checker.add_check(Check::new(
+            CheckKind::NonLowercaseVariableInFunction(name.to_string()),
+            Range::from_located(expr),
+        ));
+    }
+}
+
+/// N815
+pub fn mixed_case_variable_in_class_scope(
+    checker: &mut Checker,
+    expr: &Expr,
+    stmt: &Stmt,
+    name: &str,
+) {
+    if helpers::is_mixed_case(name)
+        && !helpers::is_namedtuple_assignment(stmt, &checker.from_imports)
+    {
+        checker.add_check(Check::new(
+            CheckKind::MixedCaseVariableInClassScope(name.to_string()),
+            Range::from_located(expr),
+        ));
+    }
+}
+
+/// N816
+pub fn mixed_case_variable_in_global_scope(
+    checker: &mut Checker,
+    expr: &Expr,
+    stmt: &Stmt,
+    name: &str,
+) {
+    if helpers::is_mixed_case(name)
+        && !helpers::is_namedtuple_assignment(stmt, &checker.from_imports)
+    {
+        checker.add_check(Check::new(
+            CheckKind::MixedCaseVariableInGlobalScope(name.to_string()),
+            Range::from_located(expr),
+        ));
+    }
+}

src/pydocstyle/plugins.rs

@@ -1,5 +1,6 @@
 use std::collections::BTreeSet;
 
+use fnv::FnvHashSet;
 use itertools::Itertools;
 use once_cell::sync::Lazy;
 use regex::Regex;
@@ -696,7 +697,7 @@ pub fn ends_with_period(checker: &mut Checker, definition: &Definition) {
             ..
         } = &docstring.node
         {
-            if let Some(string) = string.lines().next() {
+            if let Some(string) = string.trim().lines().next() {
                 if !string.ends_with('.') {
                     checker.add_check(Check::new(
                         CheckKind::EndsInPeriod,
@@ -806,7 +807,7 @@ pub fn ends_with_punctuation(checker: &mut Checker, definition: &Definition) {
             ..
         } = &docstring.node
         {
-            if let Some(string) = string.lines().next() {
+            if let Some(string) = string.trim().lines().next() {
                 if !(string.ends_with('.') || string.ends_with('!') || string.ends_with('?')) {
                     checker.add_check(Check::new(
                         CheckKind::EndsInPunctuation,
@@ -1287,7 +1288,11 @@ fn common_section(
     blanks_and_section_underline(checker, definition, context);
 }
 
-fn missing_args(checker: &mut Checker, definition: &Definition, docstrings_args: &BTreeSet<&str>) {
+fn missing_args(
+    checker: &mut Checker,
+    definition: &Definition,
+    docstrings_args: &FnvHashSet<&str>,
+) {
     if let DefinitionKind::Function(parent)
     | DefinitionKind::NestedFunction(parent)
     | DefinitionKind::Method(parent) = definition.kind
@@ -1377,7 +1382,7 @@ fn args_section(checker: &mut Checker, definition: &Definition, context: &Sectio
         checker,
         definition,
         // Collect the list of arguments documented in the docstring.
-        &BTreeSet::from_iter(args_sections.iter().filter_map(|section| {
+        &FnvHashSet::from_iter(args_sections.iter().filter_map(|section| {
             match GOOGLE_ARGS_REGEX.captures(section.as_str()) {
                 Some(caps) => caps.get(1).map(|arg_name| arg_name.as_str()),
                 None => None,
@@ -1388,7 +1393,7 @@ fn args_section(checker: &mut Checker, definition: &Definition, context: &Sectio
 
 fn parameters_section(checker: &mut Checker, definition: &Definition, context: &SectionContext) {
     // Collect the list of arguments documented in the docstring.
-    let mut docstring_args: BTreeSet<&str> = Default::default();
+    let mut docstring_args: FnvHashSet<&str> = FnvHashSet::default();
     let section_level_indent = helpers::leading_space(context.line);
     for i in 1..context.following_lines.len() {
         let current_line = context.following_lines[i - 1];

src/pyflakes/checks.rs

@@ -1,5 +1,4 @@
-use std::collections::BTreeSet;
-
+use fnv::FnvHashSet;
 use regex::Regex;
 use rustpython_parser::ast::{
     Arg, Arguments, Constant, Excepthandler, ExcepthandlerKind, Expr, ExprKind, Stmt, StmtKind,
@@ -113,7 +112,7 @@ pub fn duplicate_arguments(arguments: &Arguments) -> Vec<Check> {
     }
 
     // Search for duplicates.
-    let mut idents: BTreeSet<&str> = BTreeSet::new();
+    let mut idents: FnvHashSet<&str> = FnvHashSet::default();
     for arg in all_arguments {
         let ident = &arg.node.arg;
         if idents.contains(ident.as_str()) {

src/python/sys.rs

@@ -1,10 +1,9 @@
-use std::collections::BTreeSet;
-
+use fnv::FnvHashSet;
 use once_cell::sync::Lazy;
 
 // See: https://pycqa.github.io/isort/docs/configuration/options.html#known-standard-library
-pub static KNOWN_STANDARD_LIBRARY: Lazy<BTreeSet<&'static str>> = Lazy::new(|| {
-    BTreeSet::from([
+pub static KNOWN_STANDARD_LIBRARY: Lazy<FnvHashSet<&'static str>> = Lazy::new(|| {
+    FnvHashSet::from_iter([
         "_ast",
         "_dummy_thread",
         "_thread",

src/python/typing.rs

@@ -1,6 +1,8 @@
 use fnv::{FnvHashMap, FnvHashSet};
 use once_cell::sync::Lazy;
-use rustpython_ast::{Expr, ExprKind};
+use rustpython_ast::Expr;
+
+use crate::ast::helpers::{collect_call_paths, dealias_call_path, match_call_path};
 
 // See: https://pypi.org/project/typing-extensions/
 static TYPING_EXTENSIONS: Lazy<FnvHashSet<&'static str>> = Lazy::new(|| {
@@ -63,144 +65,144 @@ pub fn in_extensions(name: &str) -> bool {
 }
 
 // See: https://docs.python.org/3/library/typing.html
-static IMPORTED_SUBSCRIPTS: Lazy<FnvHashMap<&'static str, FnvHashSet<&'static str>>> =
-    Lazy::new(|| {
-        let mut import_map = FnvHashMap::default();
-        for (name, module) in [
-            // `collections`
-            ("ChainMap", "collections"),
-            ("Counter", "collections"),
-            ("OrderedDict", "collections"),
-            ("defaultdict", "collections"),
-            ("deque", "collections"),
-            // `collections.abc`
-            ("AsyncGenerator", "collections.abc"),
-            ("AsyncIterable", "collections.abc"),
-            ("AsyncIterator", "collections.abc"),
-            ("Awaitable", "collections.abc"),
-            ("ByteString", "collections.abc"),
-            ("Callable", "collections.abc"),
-            ("Collection", "collections.abc"),
-            ("Container", "collections.abc"),
-            ("Coroutine", "collections.abc"),
-            ("Generator", "collections.abc"),
-            ("ItemsView", "collections.abc"),
-            ("Iterable", "collections.abc"),
-            ("Iterator", "collections.abc"),
-            ("KeysView", "collections.abc"),
-            ("Mapping", "collections.abc"),
-            ("MappingView", "collections.abc"),
-            ("MutableMapping", "collections.abc"),
-            ("MutableSequence", "collections.abc"),
-            ("MutableSet", "collections.abc"),
-            ("Reversible", "collections.abc"),
-            ("Sequence", "collections.abc"),
-            ("Set", "collections.abc"),
-            ("ValuesView", "collections.abc"),
-            // `contextlib`
-            ("AbstractAsyncContextManager", "contextlib"),
-            ("AbstractContextManager", "contextlib"),
-            // `re`
-            ("Match", "re"),
-            ("Pattern", "re"),
-            // `typing`
-            ("AbstractSet", "typing"),
-            ("Annotated", "typing"),
-            ("AsyncContextManager", "typing"),
-            ("AsyncGenerator", "typing"),
-            ("AsyncIterator", "typing"),
-            ("Awaitable", "typing"),
-            ("BinaryIO", "typing"),
-            ("ByteString", "typing"),
-            ("Callable", "typing"),
-            ("ChainMap", "typing"),
-            ("ClassVar", "typing"),
-            ("Collection", "typing"),
-            ("Concatenate", "typing"),
-            ("Container", "typing"),
-            ("ContextManager", "typing"),
-            ("Coroutine", "typing"),
-            ("Counter", "typing"),
-            ("DefaultDict", "typing"),
-            ("Deque", "typing"),
-            ("Dict", "typing"),
-            ("Final", "typing"),
-            ("FrozenSet", "typing"),
-            ("Generator", "typing"),
-            ("Generic", "typing"),
-            ("IO", "typing"),
-            ("ItemsView", "typing"),
-            ("Iterable", "typing"),
-            ("Iterator", "typing"),
-            ("KeysView", "typing"),
-            ("List", "typing"),
-            ("Mapping", "typing"),
-            ("Match", "typing"),
-            ("MutableMapping", "typing"),
-            ("MutableSequence", "typing"),
-            ("MutableSet", "typing"),
-            ("Optional", "typing"),
-            ("OrderedDict", "typing"),
-            ("Pattern", "typing"),
-            ("Reversible", "typing"),
-            ("Sequence", "typing"),
-            ("Set", "typing"),
-            ("TextIO", "typing"),
-            ("Tuple", "typing"),
-            ("Type", "typing"),
-            ("TypeGuard", "typing"),
-            ("Union", "typing"),
-            ("Unpack", "typing"),
-            ("ValuesView", "typing"),
-            // `typing.io`
-            ("BinaryIO", "typing.io"),
-            ("IO", "typing.io"),
-            ("TextIO", "typing.io"),
-            // `typing.re`
-            ("Match", "typing.re"),
-            ("Pattern", "typing.re"),
-            // `typing_extensions`
-            ("Annotated", "typing_extensions"),
-            ("AsyncContextManager", "typing_extensions"),
-            ("AsyncGenerator", "typing_extensions"),
-            ("AsyncIterable", "typing_extensions"),
-            ("AsyncIterator", "typing_extensions"),
-            ("Awaitable", "typing_extensions"),
-            ("ChainMap", "typing_extensions"),
-            ("ClassVar", "typing_extensions"),
-            ("Concatenate", "typing_extensions"),
-            ("ContextManager", "typing_extensions"),
-            ("Coroutine", "typing_extensions"),
-            ("Counter", "typing_extensions"),
-            ("DefaultDict", "typing_extensions"),
-            ("Deque", "typing_extensions"),
-            ("Type", "typing_extensions"),
-            // `weakref`
-            ("WeakKeyDictionary", "weakref"),
-            ("WeakSet", "weakref"),
-            ("WeakValueDictionary", "weakref"),
-        ] {
-            import_map
-                .entry(name)
-                .or_insert_with(FnvHashSet::default)
-                .insert(module);
-        }
-        import_map
-    });
+const SUBSCRIPTS: &[(&str, &str)] = &[
+    // builtins
+    ("", "dict"),
+    ("", "frozenset"),
+    ("", "list"),
+    ("", "set"),
+    ("", "tuple"),
+    ("", "type"),
+    // `collections`
+    ("collections", "ChainMap"),
+    ("collections", "Counter"),
+    ("collections", "OrderedDict"),
+    ("collections", "defaultdict"),
+    ("collections", "deque"),
+    // `collections.abc`
+    ("collections.abc", "AsyncGenerator"),
+    ("collections.abc", "AsyncIterable"),
+    ("collections.abc", "AsyncIterator"),
+    ("collections.abc", "Awaitable"),
+    ("collections.abc", "ByteString"),
+    ("collections.abc", "Callable"),
+    ("collections.abc", "Collection"),
+    ("collections.abc", "Container"),
+    ("collections.abc", "Coroutine"),
+    ("collections.abc", "Generator"),
+    ("collections.abc", "ItemsView"),
+    ("collections.abc", "Iterable"),
+    ("collections.abc", "Iterator"),
+    ("collections.abc", "KeysView"),
+    ("collections.abc", "Mapping"),
+    ("collections.abc", "MappingView"),
+    ("collections.abc", "MutableMapping"),
+    ("collections.abc", "MutableSequence"),
+    ("collections.abc", "MutableSet"),
+    ("collections.abc", "Reversible"),
+    ("collections.abc", "Sequence"),
+    ("collections.abc", "Set"),
+    ("collections.abc", "ValuesView"),
+    // `contextlib`
+    ("contextlib", "AbstractAsyncContextManager"),
+    ("contextlib", "AbstractContextManager"),
+    // `re`
+    ("re", "Match"),
+    ("re", "Pattern"),
+    // `typing`
+    ("typing", "AbstractSet"),
+    ("typing", "AsyncContextManager"),
+    ("typing", "AsyncGenerator"),
+    ("typing", "AsyncIterator"),
+    ("typing", "Awaitable"),
+    ("typing", "BinaryIO"),
+    ("typing", "ByteString"),
+    ("typing", "Callable"),
+    ("typing", "ChainMap"),
+    ("typing", "ClassVar"),
+    ("typing", "Collection"),
+    ("typing", "Concatenate"),
+    ("typing", "Container"),
+    ("typing", "ContextManager"),
+    ("typing", "Coroutine"),
+    ("typing", "Counter"),
+    ("typing", "DefaultDict"),
+    ("typing", "Deque"),
+    ("typing", "Dict"),
+    ("typing", "Final"),
+    ("typing", "FrozenSet"),
+    ("typing", "Generator"),
+    ("typing", "Generic"),
+    ("typing", "IO"),
+    ("typing", "ItemsView"),
+    ("typing", "Iterable"),
+    ("typing", "Iterator"),
+    ("typing", "KeysView"),
+    ("typing", "List"),
+    ("typing", "Mapping"),
+    ("typing", "Match"),
+    ("typing", "MutableMapping"),
+    ("typing", "MutableSequence"),
+    ("typing", "MutableSet"),
+    ("typing", "Optional"),
+    ("typing", "OrderedDict"),
+    ("typing", "Pattern"),
+    ("typing", "Reversible"),
+    ("typing", "Sequence"),
+    ("typing", "Set"),
+    ("typing", "TextIO"),
+    ("typing", "Tuple"),
+    ("typing", "Type"),
+    ("typing", "TypeGuard"),
+    ("typing", "Union"),
+    ("typing", "Unpack"),
+    ("typing", "ValuesView"),
+    // `typing.io`
+    ("typing.io", "BinaryIO"),
+    ("typing.io", "IO"),
+    ("typing.io", "TextIO"),
+    // `typing.re`
+    ("typing.re", "Match"),
+    ("typing.re", "Pattern"),
+    // `typing_extensions`
+    ("typing_extensions", "AsyncContextManager"),
+    ("typing_extensions", "AsyncGenerator"),
+    ("typing_extensions", "AsyncIterable"),
+    ("typing_extensions", "AsyncIterator"),
+    ("typing_extensions", "Awaitable"),
+    ("typing_extensions", "ChainMap"),
+    ("typing_extensions", "ClassVar"),
+    ("typing_extensions", "Concatenate"),
+    ("typing_extensions", "ContextManager"),
+    ("typing_extensions", "Coroutine"),
+    ("typing_extensions", "Counter"),
+    ("typing_extensions", "DefaultDict"),
+    ("typing_extensions", "Deque"),
+    ("typing_extensions", "Type"),
+    // `weakref`
+    ("weakref", "WeakKeyDictionary"),
+    ("weakref", "WeakSet"),
+    ("weakref", "WeakValueDictionary"),
+];
+
+// See: https://docs.python.org/3/library/typing.html
+const PEP_583_SUBSCRIPTS: &[(&str, &str)] = &[
+    // `typing`
+    ("typing", "Annotated"),
+    // `typing_extensions`
+    ("typing_extensions", "Annotated"),
+];
 
-// These are all assumed to come from the `typing` module.
 // See: https://peps.python.org/pep-0585/
-static PEP_585_BUILTINS_ELIGIBLE: Lazy<FnvHashSet<&'static str>> =
-    Lazy::new(|| FnvHashSet::from_iter(["Dict", "FrozenSet", "List", "Set", "Tuple", "Type"]));
-
-// These are all assumed to come from the `typing` module.
-// See: https://peps.python.org/pep-0585/
-static PEP_585_BUILTINS: Lazy<FnvHashSet<&'static str>> =
-    Lazy::new(|| FnvHashSet::from_iter(["dict", "frozenset", "list", "set", "tuple", "type"]));
-
-fn is_pep593_annotated_subscript(name: &str) -> bool {
-    name == "Annotated"
-}
+const PEP_585_BUILTINS_ELIGIBLE: &[(&str, &str)] = &[
+    ("typing", "Dict"),
+    ("typing", "FrozenSet"),
+    ("typing", "List"),
+    ("typing", "Set"),
+    ("typing", "Tuple"),
+    ("typing", "Type"),
+    ("typing_extensions", "Type"),
+];
 
 pub enum SubscriptKind {
     AnnotatedSubscript,
@@ -210,72 +212,38 @@ pub enum SubscriptKind {
 pub fn match_annotated_subscript(
     expr: &Expr,
     from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    import_aliases: &FnvHashMap<&str, &str>,
 ) -> Option<SubscriptKind> {
-    match &expr.node {
-        ExprKind::Attribute { attr, value, .. } => {
-            if let ExprKind::Name { id, .. } = &value.node {
-                // If `id` is `typing` and `attr` is `Union`, verify that `typing.Union` is an
-                // annotated subscript.
-                if IMPORTED_SUBSCRIPTS
-                    .get(&attr.as_str())
-                    .map(|imports| imports.contains(&id.as_str()))
-                    .unwrap_or_default()
-                {
-                    return if is_pep593_annotated_subscript(attr) {
-                        Some(SubscriptKind::PEP593AnnotatedSubscript)
-                    } else {
-                        Some(SubscriptKind::AnnotatedSubscript)
-                    };
-                }
-            }
-        }
-        ExprKind::Name { id, .. } => {
-            // Built-ins (no import necessary).
-            if PEP_585_BUILTINS.contains(&id.as_str()) {
+    let call_path = dealias_call_path(collect_call_paths(expr), import_aliases);
+    if !call_path.is_empty() {
+        for (module, member) in SUBSCRIPTS {
+            if match_call_path(&call_path, module, member, from_imports) {
                 return Some(SubscriptKind::AnnotatedSubscript);
             }
-
-            // Verify that, e.g., `Union` is a reference to `typing.Union`.
-            if let Some(modules) = IMPORTED_SUBSCRIPTS.get(&id.as_str()) {
-                for module in modules {
-                    if from_imports
-                        .get(module)
-                        .map(|imports| imports.contains(&id.as_str()) || imports.contains("*"))
-                        .unwrap_or_default()
-                    {
-                        return if is_pep593_annotated_subscript(id) {
-                            Some(SubscriptKind::PEP593AnnotatedSubscript)
-                        } else {
-                            Some(SubscriptKind::AnnotatedSubscript)
-                        };
-                    }
-                }
+        }
+        for (module, member) in PEP_583_SUBSCRIPTS {
+            if match_call_path(&call_path, module, member, from_imports) {
+                return Some(SubscriptKind::PEP593AnnotatedSubscript);
             }
         }
-        _ => {}
     }
     None
 }
 
 /// Returns `true` if `Expr` represents a reference to a typing object with a
-/// PEP 585 built-in. Note that none of the PEP 585 built-ins are in
-/// `typing_extensions`.
-pub fn is_pep585_builtin(expr: &Expr, from_imports: &FnvHashMap<&str, FnvHashSet<&str>>) -> bool {
-    match &expr.node {
-        ExprKind::Attribute { attr, value, .. } => {
-            if let ExprKind::Name { id, .. } = &value.node {
-                id == "typing" && PEP_585_BUILTINS_ELIGIBLE.contains(&attr.as_str())
-            } else {
-                false
+/// PEP 585 built-in.
+pub fn is_pep585_builtin(
+    expr: &Expr,
+    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    import_aliases: &FnvHashMap<&str, &str>,
+) -> bool {
+    let call_path = dealias_call_path(collect_call_paths(expr), import_aliases);
+    if !call_path.is_empty() {
+        for (module, member) in PEP_585_BUILTINS_ELIGIBLE {
+            if match_call_path(&call_path, module, member, from_imports) {
+                return true;
             }
         }
-        ExprKind::Name { id, .. } => {
-            from_imports
-                .get("typing")
-                .map(|imports| imports.contains(&id.as_str()) || imports.contains("*"))
-                .unwrap_or_default()
-                && PEP_585_BUILTINS_ELIGIBLE.contains(&id.as_str())
-        }
-        _ => false,
     }
+    false
 }

src/pyupgrade/checks.rs

@@ -163,7 +163,8 @@ pub fn type_of_primitive(func: &Expr, args: &[Expr], location: Range) -> Option<
 pub fn unnecessary_lru_cache_params(
     decorator_list: &[Expr],
     target_version: PythonVersion,
-    imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    from_imports: &FnvHashMap<&str, FnvHashSet<&str>>,
+    import_aliases: &FnvHashMap<&str, &str>,
 ) -> Option<Check> {
     for expr in decorator_list.iter() {
         if let ExprKind::Call {
@@ -172,7 +173,14 @@ pub fn unnecessary_lru_cache_params(
             keywords,
         } = &expr.node
         {
-            if args.is_empty() && helpers::match_module_member(func, "functools.lru_cache", imports)
+            if args.is_empty()
+                && helpers::match_module_member(
+                    func,
+                    "functools",
+                    "lru_cache",
+                    from_imports,
+                    import_aliases,
+                )
             {
                 // Ex) `functools.lru_cache()`
                 if keywords.is_empty() {

src/pyupgrade/plugins/unnecessary_lru_cache_params.rs

@@ -9,6 +9,7 @@ pub fn unnecessary_lru_cache_params(checker: &mut Checker, decorator_list: &[Exp
         decorator_list,
         checker.settings.target_version,
         &checker.from_imports,
+        &checker.import_aliases,
     ) {
         if checker.patch() {
             if let Some(fix) =

src/pyupgrade/plugins/use_pep585_annotation.rs

@@ -7,13 +7,14 @@ use crate::checks::{Check, CheckKind};
 
 /// U006
 pub fn use_pep585_annotation(checker: &mut Checker, expr: &Expr, id: &str) {
+    let replacement = checker.import_aliases.get(id).unwrap_or(&id);
     let mut check = Check::new(
-        CheckKind::UsePEP585Annotation(id.to_string()),
+        CheckKind::UsePEP585Annotation(replacement.to_string()),
         Range::from_located(expr),
     );
     if checker.patch() {
         check.amend(Fix::replacement(
-            id.to_lowercase(),
+            replacement.to_lowercase(),
             expr.location,
             expr.end_location.unwrap(),
         ));

src/pyupgrade/plugins/use_pep604_annotation.rs

@@ -1,5 +1,6 @@
 use rustpython_ast::{Constant, Expr, ExprKind, Operator};
 
+use crate::ast::helpers::{collect_call_paths, dealias_call_path};
 use crate::ast::types::Range;
 use crate::autofix::Fix;
 use crate::check_ast::Checker;
@@ -43,7 +44,8 @@ fn union(elts: &[Expr]) -> Expr {
 
 /// U007
 pub fn use_pep604_annotation(checker: &mut Checker, expr: &Expr, value: &Expr, slice: &Expr) {
-    if checker.match_typing_module(value, "Optional") {
+    let call_path = dealias_call_path(collect_call_paths(value), &checker.import_aliases);
+    if checker.match_typing_call_path(&call_path, "Optional") {
         let mut check = Check::new(CheckKind::UsePEP604Annotation, Range::from_located(expr));
         if checker.patch() {
             let mut generator = SourceGenerator::new();
@@ -58,7 +60,7 @@ pub fn use_pep604_annotation(checker: &mut Checker, expr: &Expr, value: &Expr, s
             }
         }
         checker.add_check(check);
-    } else if checker.match_typing_module(value, "Union") {
+    } else if checker.match_typing_call_path(&call_path, "Union") {
         let mut check = Check::new(CheckKind::UsePEP604Annotation, Range::from_located(expr));
         if checker.patch() {
             match &slice.node {

src/settings/mod.rs

@@ -114,6 +114,7 @@ impl Hash for Settings {
         self.target_version.hash(state);
         // Add plugin properties in alphabetical order.
         self.flake8_annotations.hash(state);
+        self.flake8_bugbear.hash(state);
         self.flake8_quotes.hash(state);
         self.isort.hash(state);
         self.pep8_naming.hash(state);

src/settings/options.rs

@@ -1,7 +1,6 @@
 //! Options that the user can provide via pyproject.toml.
 
-use std::collections::BTreeMap;
-
+use fnv::FnvHashMap;
 use serde::{Deserialize, Serialize};
 
 use crate::checks_gen::CheckCodePrefix;
@@ -29,5 +28,5 @@ pub struct Options {
     pub isort: Option<isort::settings::Options>,
     pub pep8_naming: Option<pep8_naming::settings::Options>,
     // Tables are required to go last.
-    pub per_file_ignores: Option<BTreeMap<String, Vec<CheckCodePrefix>>>,
+    pub per_file_ignores: Option<FnvHashMap<String, Vec<CheckCodePrefix>>>,
 }

src/settings/pyproject.rs

@@ -96,12 +96,12 @@ pub fn load_options(pyproject: &Option<PathBuf>) -> Result<Options> {
 
 #[cfg(test)]
 mod tests {
-    use std::collections::BTreeMap;
     use std::env::current_dir;
     use std::path::PathBuf;
     use std::str::FromStr;
 
     use anyhow::Result;
+    use fnv::FnvHashMap;
 
     use crate::checks_gen::CheckCodePrefix;
     use crate::flake8_quotes::settings::Quote;
@@ -346,7 +346,7 @@ other-attribute = 1
                 extend_select: None,
                 ignore: None,
                 extend_ignore: None,
-                per_file_ignores: Some(BTreeMap::from([(
+                per_file_ignores: Some(FnvHashMap::from_iter([(
                     "__init__.py".to_string(),
                     vec![CheckCodePrefix::F401]
                 ),])),

src/snapshots/ruff__linter__tests__B020_B020.py.snap

@@ -0,0 +1,32 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    LoopVariableOverridesIterator: items
+  location:
+    row: 8
+    column: 4
+  end_location:
+    row: 8
+    column: 9
+  fix: ~
+- kind:
+    LoopVariableOverridesIterator: values
+  location:
+    row: 21
+    column: 9
+  end_location:
+    row: 21
+    column: 15
+  fix: ~
+- kind:
+    LoopVariableOverridesIterator: vars
+  location:
+    row: 36
+    column: 4
+  end_location:
+    row: 36
+    column: 8
+  fix: ~
+

src/snapshots/ruff__linter__tests__B022_B022.py.snap

@@ -0,0 +1,21 @@
+---
+source: src/linter.r
+expression: checks
+---
+- kind: UselessContextlibSuppress
+  location:
+    row: 9
+    column: 5
+  end_location:
+    row: 9
+    column: 26
+  fix: ~
+- kind: UselessContextlibSuppress
+  location:
+    row: 12
+    column: 5
+  end_location:
+    row: 12
+    column: 15
+  fix: ~
+

src/snapshots/ruff__linter__tests__B024_B024.py.snap

@@ -0,0 +1,59 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    AbstractBaseClassWithoutAbstractMethod: Base_1
+  location:
+    row: 17
+    column: 0
+  end_location:
+    row: 22
+    column: 0
+  fix: ~
+- kind:
+    AbstractBaseClassWithoutAbstractMethod: MetaBase_1
+  location:
+    row: 58
+    column: 0
+  end_location:
+    row: 63
+    column: 0
+  fix: ~
+- kind:
+    AbstractBaseClassWithoutAbstractMethod: abc_Base_1
+  location:
+    row: 69
+    column: 0
+  end_location:
+    row: 74
+    column: 0
+  fix: ~
+- kind:
+    AbstractBaseClassWithoutAbstractMethod: abc_Base_2
+  location:
+    row: 74
+    column: 0
+  end_location:
+    row: 79
+    column: 0
+  fix: ~
+- kind:
+    AbstractBaseClassWithoutAbstractMethod: notabc_Base_1
+  location:
+    row: 79
+    column: 0
+  end_location:
+    row: 84
+    column: 0
+  fix: ~
+- kind:
+    AbstractBaseClassWithoutAbstractMethod: abc_set_class_variable_4
+  location:
+    row: 128
+    column: 0
+  end_location:
+    row: 130
+    column: 0
+  fix: ~
+

src/snapshots/ruff__linter__tests__B027_B027.py.snap

@@ -0,0 +1,41 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    EmptyMethodWithoutAbstractDecorator: AbstractClass
+  location:
+    row: 12
+    column: 4
+  end_location:
+    row: 15
+    column: 4
+  fix: ~
+- kind:
+    EmptyMethodWithoutAbstractDecorator: AbstractClass
+  location:
+    row: 15
+    column: 4
+  end_location:
+    row: 18
+    column: 4
+  fix: ~
+- kind:
+    EmptyMethodWithoutAbstractDecorator: AbstractClass
+  location:
+    row: 18
+    column: 4
+  end_location:
+    row: 22
+    column: 4
+  fix: ~
+- kind:
+    EmptyMethodWithoutAbstractDecorator: AbstractClass
+  location:
+    row: 22
+    column: 4
+  end_location:
+    row: 29
+    column: 4
+  fix: ~
+

src/snapshots/ruff__linter__tests__D400_D.py.snap

@@ -2,30 +2,6 @@
 source: src/linter.rs
 expression: checks
 ---
-- kind: EndsInPeriod
-  location:
-    row: 124
-    column: 4
-  end_location:
-    row: 126
-    column: 7
-  fix: ~
-- kind: EndsInPeriod
-  location:
-    row: 283
-    column: 4
-  end_location:
-    row: 283
-    column: 33
-  fix: ~
-- kind: EndsInPeriod
-  location:
-    row: 288
-    column: 4
-  end_location:
-    row: 288
-    column: 37
-  fix: ~
 - kind: EndsInPeriod
   location:
     row: 350

src/snapshots/ruff__linter__tests__D415_D.py.snap

@@ -2,30 +2,6 @@
 source: src/linter.rs
 expression: checks
 ---
-- kind: EndsInPunctuation
-  location:
-    row: 124
-    column: 4
-  end_location:
-    row: 126
-    column: 7
-  fix: ~
-- kind: EndsInPunctuation
-  location:
-    row: 283
-    column: 4
-  end_location:
-    row: 283
-    column: 33
-  fix: ~
-- kind: EndsInPunctuation
-  location:
-    row: 288
-    column: 4
-  end_location:
-    row: 288
-    column: 37
-  fix: ~
 - kind: EndsInPunctuation
   location:
     row: 350

src/snapshots/ruff__linter__tests__F401_F401_6.py.snap

@@ -42,4 +42,44 @@ expression: checks
         row: 11
         column: 0
     applied: false
+- kind:
+    UnusedImport:
+      - - background
+      - false
+  location:
+    row: 17
+    column: 0
+  end_location:
+    row: 17
+    column: 17
+  fix:
+    patch:
+      content: ""
+      location:
+        row: 17
+        column: 0
+      end_location:
+        row: 18
+        column: 0
+    applied: false
+- kind:
+    UnusedImport:
+      - - datastructures
+      - false
+  location:
+    row: 20
+    column: 0
+  end_location:
+    row: 20
+    column: 35
+  fix:
+    patch:
+      content: ""
+      location:
+        row: 20
+        column: 0
+      end_location:
+        row: 21
+        column: 0
+    applied: false
 

src/snapshots/ruff__linter__tests__F821_F821_4.py.snap

@@ -0,0 +1,50 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    UndefinedName: Model
+  location:
+    row: 4
+    column: 9
+  end_location:
+    row: 4
+    column: 16
+  fix: ~
+- kind:
+    UndefinedName: Model
+  location:
+    row: 9
+    column: 10
+  end_location:
+    row: 9
+    column: 17
+  fix: ~
+- kind:
+    UndefinedName: Model
+  location:
+    row: 14
+    column: 14
+  end_location:
+    row: 14
+    column: 21
+  fix: ~
+- kind:
+    UndefinedName: Model
+  location:
+    row: 19
+    column: 30
+  end_location:
+    row: 19
+    column: 37
+  fix: ~
+- kind:
+    UndefinedName: Model
+  location:
+    row: 24
+    column: 18
+  end_location:
+    row: 24
+    column: 25
+  fix: ~
+

src/snapshots/ruff__linter__tests__F821_F821_5.py.snap

@@ -0,0 +1,14 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    UndefinedName: InnerClass
+  location:
+    row: 5
+    column: 29
+  end_location:
+    row: 5
+    column: 41
+  fix: ~
+

src/snapshots/ruff__linter__tests__N806_N806.py.snap

@@ -5,19 +5,19 @@ expression: checks
 - kind:
     NonLowercaseVariableInFunction: Camel
   location:
-    row: 3
+    row: 7
     column: 4
   end_location:
-    row: 3
+    row: 7
     column: 9
   fix: ~
 - kind:
     NonLowercaseVariableInFunction: CONSTANT
   location:
-    row: 4
+    row: 8
     column: 4
   end_location:
-    row: 4
+    row: 8
     column: 12
   fix: ~
 

src/snapshots/ruff__linter__tests__N815_N815.py.snap

@@ -5,28 +5,28 @@ expression: checks
 - kind:
     MixedCaseVariableInClassScope: mixedCase
   location:
-    row: 4
+    row: 8
     column: 4
   end_location:
-    row: 4
+    row: 8
     column: 13
   fix: ~
 - kind:
     MixedCaseVariableInClassScope: _mixedCase
   location:
-    row: 5
+    row: 9
     column: 4
   end_location:
-    row: 5
+    row: 9
     column: 14
   fix: ~
 - kind:
     MixedCaseVariableInClassScope: mixed_Case
   location:
-    row: 6
+    row: 10
     column: 4
   end_location:
-    row: 6
+    row: 10
     column: 14
   fix: ~
 

src/snapshots/ruff__linter__tests__N816_N816.py.snap

@@ -5,28 +5,28 @@ expression: checks
 - kind:
     MixedCaseVariableInGlobalScope: mixedCase
   location:
-    row: 3
+    row: 6
     column: 0
   end_location:
-    row: 3
+    row: 6
     column: 9
   fix: ~
 - kind:
     MixedCaseVariableInGlobalScope: _mixedCase
   location:
-    row: 4
+    row: 7
     column: 0
   end_location:
-    row: 4
+    row: 7
     column: 10
   fix: ~
 - kind:
     MixedCaseVariableInGlobalScope: mixed_Case
   location:
-    row: 5
+    row: 8
     column: 0
   end_location:
-    row: 5
+    row: 8
     column: 10
   fix: ~
 

src/snapshots/ruff__linter__tests__U006_U006.py.snap

@@ -9,7 +9,7 @@ expression: checks
     column: 9
   end_location:
     row: 4
-    column: 13
+    column: 20
   fix:
     patch:
       content: list
@@ -18,7 +18,7 @@ expression: checks
         column: 9
       end_location:
         row: 4
-        column: 13
+        column: 20
     applied: false
 - kind:
     UsePEP585Annotation: List
@@ -27,7 +27,7 @@ expression: checks
     column: 9
   end_location:
     row: 11
-    column: 20
+    column: 13
   fix:
     patch:
       content: list
@@ -36,6 +36,42 @@ expression: checks
         column: 9
       end_location:
         row: 11
-        column: 20
+        column: 13
+    applied: false
+- kind:
+    UsePEP585Annotation: List
+  location:
+    row: 18
+    column: 9
+  end_location:
+    row: 18
+    column: 15
+  fix:
+    patch:
+      content: list
+      location:
+        row: 18
+        column: 9
+      end_location:
+        row: 18
+        column: 15
+    applied: false
+- kind:
+    UsePEP585Annotation: List
+  location:
+    row: 25
+    column: 9
+  end_location:
+    row: 25
+    column: 14
+  fix:
+    patch:
+      content: list
+      location:
+        row: 25
+        column: 9
+      end_location:
+        row: 25
+        column: 14
     applied: false
 

src/snapshots/ruff__linter__tests__YTT101_YTT101.py.snap

@@ -18,4 +18,12 @@ expression: checks
     row: 7
     column: 13
   fix: ~
+- kind: SysVersionSlice3Referenced
+  location:
+    row: 8
+    column: 6
+  end_location:
+    row: 8
+    column: 7
+  fix: ~
 

src/updates.rs

@@ -0,0 +1,75 @@
+use std::fs::{create_dir_all, read_to_string, File};
+use std::io::Write;
+use std::path::{Path, PathBuf};
+
+use anyhow::Result;
+use colored::Colorize;
+
+const CARGO_PKG_NAME: &str = env!("CARGO_PKG_NAME");
+const CARGO_PKG_VERSION: &str = env!("CARGO_PKG_VERSION");
+
+fn cache_dir() -> &'static str {
+    "./.ruff_cache"
+}
+
+fn file_path() -> PathBuf {
+    Path::new(cache_dir()).join(".update-informer")
+}
+
+/// Get the "latest" version for which the user has been informed.
+fn get_latest() -> Result<Option<String>> {
+    let path = file_path();
+    if path.exists() {
+        Ok(Some(read_to_string(path)?.trim().to_string()))
+    } else {
+        Ok(None)
+    }
+}
+
+/// Set the "latest" version for which the user has been informed.
+fn set_latest(version: &str) -> Result<()> {
+    create_dir_all(cache_dir())?;
+    let path = file_path();
+    let mut file = File::create(path)?;
+    file.write_all(version.trim().as_bytes())
+        .map_err(|e| e.into())
+}
+
+/// Update the user if a newer version is available.
+pub fn check_for_updates() -> Result<()> {
+    use update_informer::{registry, Check};
+
+    let informer = update_informer::new(registry::PyPI, CARGO_PKG_NAME, CARGO_PKG_VERSION);
+
+    if let Some(new_version) = informer
+        .check_version()
+        .ok()
+        .flatten()
+        .map(|version| version.to_string())
+    {
+        // If we've already notified the user about this version, return early.
+        if let Some(latest_version) = get_latest()? {
+            if latest_version == new_version {
+                return Ok(());
+            }
+        }
+        set_latest(&new_version)?;
+
+        let msg = format!(
+            "A new version of {pkg_name} is available: v{pkg_version} -> {new_version}",
+            pkg_name = CARGO_PKG_NAME.italic().cyan(),
+            pkg_version = CARGO_PKG_VERSION,
+            new_version = new_version.green()
+        );
+
+        let cmd = format!(
+            "Run to update: {cmd} {pkg_name}",
+            cmd = "pip3 install --upgrade".green(),
+            pkg_name = CARGO_PKG_NAME.green()
+        );
+
+        println!("\n{msg}\n{cmd}");
+    }
+
+    Ok(())
+}