Run cargo dev commands

Add ruff-lsp to README

.github/workflows/ci.yaml

@@ -39,9 +39,12 @@ jobs:
       - run: ./target/release/ruff_dev generate-rules-table
       - run: ./target/release/ruff_dev generate-options
       - run: git diff --quiet README.md || echo "::error file=README.md::This file is outdated. You may have to rerun 'cargo dev generate-options' and/or 'cargo dev generate-rules-table'."
-      - run: ./target/release/ruff_dev generate-check-code-prefix && cargo fmt -- src/checks_gen.rs
+      - run: ./target/release/ruff_dev generate-check-code-prefix
       - run: git diff --quiet src/checks_gen.rs || echo "::error file=src/checks_gen.rs::This file is outdated. You may have to rerun 'cargo dev generate-check-code-prefix'."
       - run: git diff --exit-code -- README.md src/checks_gen.rs
+      - run: ./target/release/ruff_dev generate-json-schema
+      - run: git diff --quiet ruff.schema.json || echo "::error file=ruff.schema.json::This file is outdated. You may have to rerun 'cargo dev generate-json-schema'."
+      - run: git diff --exit-code -- ruff.schema.json
 
   cargo_fmt:
     name: "cargo fmt"
@@ -115,7 +118,9 @@ jobs:
             ${{ runner.os }}-build-${{ env.cache-name }}-
             ${{ runner.os }}-build-
             ${{ runner.os }}-
+      - run: pip install black[d]==22.12.0
       - run: cargo test --all
+      - run: cargo test --package ruff --test black_compatibility_test -- --ignored
 
   maturin_build:
     name: "maturin build"
@@ -129,7 +134,7 @@ jobs:
           override: true
       - uses: actions/setup-python@v4
         with:
-          python-version: "3.10"
+          python-version: "3.11"
       - run: pip install maturin
       - uses: actions/cache@v3
         env:

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/charliermarsh/ruff-pre-commit
-    rev: v0.0.182
+    rev: v0.0.193
     hooks:
       - id: ruff
 

CONTRIBUTING.md

@@ -48,8 +48,8 @@ prior to merging.
 There are four phases to adding a new lint rule:
 
 1. Define the rule in `src/checks.rs`.
-2. Define the _logic_ for triggering the rule in `src/check_ast.rs` (for AST-based checks),
-   `src/check_tokens.rs` (for token-based checks), or `src/check_lines.rs` (for text-based checks).
+2. Define the _logic_ for triggering the rule in `src/checkers/ast.rs` (for AST-based checks),
+   `src/checkers/tokens.rs` (for token-based checks), or `src/checkers/lines.rs` (for text-based checks).
 3. Add a test fixture.
 4. Update the generated files (documentation and generated code).
 
@@ -105,7 +105,8 @@ You may also want to add the new configuration option to the `flake8-to-ruff` to
 responsible for converting `flake8` configuration files to Ruff's TOML format. This logic
 lives in `flake8_to_ruff/src/converter.rs`.
 
-To update the documentation for supported configuration options, run `cargo dev generate-options`.
+Run `cargo dev generate-options` to update the documentation for supported configuration options,
+and `cargo dev generate-json-schema` to update the JSON schema for `tool.ruff` in `pyproject.toml`.
 
 ## Release process
 

Cargo.lock

@@ -644,6 +644,12 @@ version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fea41bba32d969b513997752735605054bc0dfa92b4c56bf1189f2e174be7a10"
 
+[[package]]
+name = "dyn-clone"
+version = "1.0.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c9b0705efd4599c15a38151f4721f7bc388306f61084d3bfd50bd07fbca5cb60"
+
 [[package]]
 name = "either"
 version = "1.8.0"
@@ -724,7 +730,7 @@ checksum = "0ce7134b9999ecaf8bcd65542e436736ef32ddca1b3e06094cb6ec5755203b80"
 
 [[package]]
 name = "flake8-to-ruff"
-version = "0.0.182-dev.0"
+version = "0.0.193-dev.0"
 dependencies = [
  "anyhow",
  "clap 4.0.29",
@@ -735,6 +741,8 @@ dependencies = [
  "rustc-hash",
  "serde",
  "serde_json",
+ "strum",
+ "strum_macros",
  "toml",
 ]
 
@@ -1845,7 +1853,7 @@ dependencies = [
 
 [[package]]
 name = "ruff"
-version = "0.0.182"
+version = "0.0.193"
 dependencies = [
  "annotate-snippets 0.9.1",
  "anyhow",
@@ -1886,8 +1894,10 @@ dependencies = [
  "rustpython-ast",
  "rustpython-common",
  "rustpython-parser",
+ "schemars",
  "serde",
  "serde_json",
+ "shellexpand",
  "strum",
  "strum_macros",
  "test-case",
@@ -1895,12 +1905,13 @@ dependencies = [
  "titlecase",
  "toml",
  "update-informer",
+ "ureq",
  "walkdir",
 ]
 
 [[package]]
 name = "ruff_dev"
-version = "0.0.182"
+version = "0.0.193"
 dependencies = [
  "anyhow",
  "clap 4.0.29",
@@ -1912,13 +1923,15 @@ dependencies = [
  "rustpython-ast",
  "rustpython-common",
  "rustpython-parser",
+ "schemars",
+ "serde_json",
  "strum",
  "strum_macros",
 ]
 
 [[package]]
 name = "ruff_macros"
-version = "0.0.182"
+version = "0.0.193"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1961,7 +1974,7 @@ dependencies = [
 [[package]]
 name = "rustpython-ast"
 version = "0.1.0"
-source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
+source = "git+https://github.com/RustPython/RustPython.git?rev=1b6cb170e925a43d605b3fed9f6b878e63e47744#1b6cb170e925a43d605b3fed9f6b878e63e47744"
 dependencies = [
  "num-bigint",
  "rustpython-common",
@@ -1971,7 +1984,7 @@ dependencies = [
 [[package]]
 name = "rustpython-common"
 version = "0.0.0"
-source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
+source = "git+https://github.com/RustPython/RustPython.git?rev=1b6cb170e925a43d605b3fed9f6b878e63e47744#1b6cb170e925a43d605b3fed9f6b878e63e47744"
 dependencies = [
  "ascii",
  "cfg-if 1.0.0",
@@ -1994,7 +2007,7 @@ dependencies = [
 [[package]]
 name = "rustpython-compiler-core"
 version = "0.1.2"
-source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
+source = "git+https://github.com/RustPython/RustPython.git?rev=1b6cb170e925a43d605b3fed9f6b878e63e47744#1b6cb170e925a43d605b3fed9f6b878e63e47744"
 dependencies = [
  "bincode",
  "bitflags",
@@ -2011,7 +2024,7 @@ dependencies = [
 [[package]]
 name = "rustpython-parser"
 version = "0.1.2"
-source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
+source = "git+https://github.com/RustPython/RustPython.git?rev=1b6cb170e925a43d605b3fed9f6b878e63e47744#1b6cb170e925a43d605b3fed9f6b878e63e47744"
 dependencies = [
  "ahash",
  "anyhow",
@@ -2054,6 +2067,30 @@ dependencies = [
  "winapi-util",
 ]
 
+[[package]]
+name = "schemars"
+version = "0.8.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2a5fb6c61f29e723026dc8e923d94c694313212abbecbbe5f55a7748eec5b307"
+dependencies = [
+ "dyn-clone",
+ "schemars_derive",
+ "serde",
+ "serde_json",
+]
+
+[[package]]
+name = "schemars_derive"
+version = "0.8.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f188d036977451159430f3b8dc82ec76364a42b7e289c2b18a9a18f4470058e9"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "serde_derive_internals",
+ "syn",
+]
+
 [[package]]
 name = "scopeguard"
 version = "1.1.0"
@@ -2103,16 +2140,36 @@ dependencies = [
 ]
 
 [[package]]
-name = "serde_json"
-version = "1.0.89"
+name = "serde_derive_internals"
+version = "0.26.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "020ff22c755c2ed3f8cf162dbb41a7268d934702f3ed3631656ea597e08fc3db"
+checksum = "85bf8229e7920a9f636479437026331ce11aa132b4dde37d121944a44d6e5f3c"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "serde_json"
+version = "1.0.91"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "877c235533714907a8c2464236f5c4b2a17262ef1bd71f38f35ea592c8da6883"
 dependencies = [
  "itoa",
  "ryu",
  "serde",
 ]
 
+[[package]]
+name = "shellexpand"
+version = "3.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd1c7ddea665294d484c39fd0c0d2b7e35bbfe10035c5fe1854741a57f6880e1"
+dependencies = [
+ "dirs 4.0.0",
+]
+
 [[package]]
 name = "similar"
 version = "2.2.1"

Cargo.toml

@@ -6,7 +6,7 @@ members = [
 
 [package]
 name = "ruff"
-version = "0.0.182"
+version = "0.0.193"
 edition = "2021"
 rust-version = "1.65.0"
 
@@ -43,13 +43,15 @@ quick-junit = { version = "0.3.2" }
 rayon = { version = "1.5.3" }
 regex = { version = "1.6.0" }
 ropey = { version = "1.5.0", features = ["cr_lines", "simd"], default-features = false }
-ruff_macros = { version = "0.0.182", path = "ruff_macros" }
+ruff_macros = { version = "0.0.193", path = "ruff_macros" }
 rustc-hash = { version = "1.1.0" }
-rustpython-ast = { features = ["unparse"], git = "https://github.com/RustPython/RustPython.git", rev = "8d879a53197f9c73062f6160410bdba796a71cbf" }
-rustpython-common = { git = "https://github.com/RustPython/RustPython.git", rev = "8d879a53197f9c73062f6160410bdba796a71cbf" }
-rustpython-parser = { features = ["lalrpop"], git = "https://github.com/RustPython/RustPython.git", rev = "8d879a53197f9c73062f6160410bdba796a71cbf" }
+rustpython-ast = { features = ["unparse"], git = "https://github.com/RustPython/RustPython.git", rev = "1b6cb170e925a43d605b3fed9f6b878e63e47744" }
+rustpython-common = { git = "https://github.com/RustPython/RustPython.git", rev = "1b6cb170e925a43d605b3fed9f6b878e63e47744" }
+rustpython-parser = { features = ["lalrpop"], git = "https://github.com/RustPython/RustPython.git", rev = "1b6cb170e925a43d605b3fed9f6b878e63e47744" }
+schemars = { version = "0.8.11" }
 serde = { version = "1.0.147", features = ["derive"] }
 serde_json = { version = "1.0.87" }
+shellexpand = { version = "3.0.0" }
 strum = { version = "0.24.1", features = ["strum_macros"] }
 strum_macros = { version = "0.24.3" }
 textwrap = { version = "0.16.0" }
@@ -71,6 +73,7 @@ assert_cmd = { version = "2.0.4" }
 criterion = { version = "0.4.0" }
 insta = { version = "1.19.1", features = ["yaml"] }
 test-case = { version = "2.2.2" }
+ureq = { version = "2.5.0", features = [] }
 
 [features]
 default = ["update-informer"]

flake8_to_ruff/Cargo.lock

@@ -771,7 +771,7 @@ checksum = "0ce7134b9999ecaf8bcd65542e436736ef32ddca1b3e06094cb6ec5755203b80"
 
 [[package]]
 name = "flake8_to_ruff"
-version = "0.0.182"
+version = "0.0.193"
 dependencies = [
  "anyhow",
  "clap",
@@ -1975,7 +1975,7 @@ dependencies = [
 
 [[package]]
 name = "ruff"
-version = "0.0.182"
+version = "0.0.193"
 dependencies = [
  "anyhow",
  "bincode",
@@ -2028,7 +2028,7 @@ dependencies = [
 [[package]]
 name = "rustpython-ast"
 version = "0.1.0"
-source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
+source = "git+https://github.com/RustPython/RustPython.git?rev=1b6cb170e925a43d605b3fed9f6b878e63e47744#1b6cb170e925a43d605b3fed9f6b878e63e47744"
 dependencies = [
  "num-bigint",
  "rustpython-common",
@@ -2038,7 +2038,7 @@ dependencies = [
 [[package]]
 name = "rustpython-common"
 version = "0.0.0"
-source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
+source = "git+https://github.com/RustPython/RustPython.git?rev=1b6cb170e925a43d605b3fed9f6b878e63e47744#1b6cb170e925a43d605b3fed9f6b878e63e47744"
 dependencies = [
  "ascii",
  "cfg-if 1.0.0",
@@ -2061,7 +2061,7 @@ dependencies = [
 [[package]]
 name = "rustpython-compiler-core"
 version = "0.1.2"
-source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
+source = "git+https://github.com/RustPython/RustPython.git?rev=1b6cb170e925a43d605b3fed9f6b878e63e47744#1b6cb170e925a43d605b3fed9f6b878e63e47744"
 dependencies = [
  "bincode",
  "bitflags",
@@ -2078,7 +2078,7 @@ dependencies = [
 [[package]]
 name = "rustpython-parser"
 version = "0.1.2"
-source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
+source = "git+https://github.com/RustPython/RustPython.git?rev=1b6cb170e925a43d605b3fed9f6b878e63e47744#1b6cb170e925a43d605b3fed9f6b878e63e47744"
 dependencies = [
  "ahash",
  "anyhow",

flake8_to_ruff/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "flake8-to-ruff"
-version = "0.0.182-dev.0"
+version = "0.0.193-dev.0"
 edition = "2021"
 
 [lib]
@@ -16,6 +16,8 @@ ruff = { path = "..", default-features = false }
 rustc-hash = { version = "1.1.0" }
 serde = { version = "1.0.147", features = ["derive"] }
 serde_json = { version = "1.0.87" }
+strum = { version = "0.24.1", features = ["strum_macros"] }
+strum_macros = { version = "0.24.3" }
 toml = { version = "0.5.9" }
 
 [dev-dependencies]

flake8_to_ruff/examples/cryptography/pyproject.toml

@@ -0,0 +1,65 @@
+[build-system]
+requires = [
+    # The minimum setuptools version is specific to the PEP 517 backend,
+    # and may be stricter than the version required in `setup.cfg`
+    "setuptools>=40.6.0,!=60.9.0",
+    "wheel",
+    # Must be kept in sync with the `install_requirements` in `setup.cfg`
+    "cffi>=1.12; platform_python_implementation != 'PyPy'",
+    "setuptools-rust>=0.11.4",
+]
+build-backend = "setuptools.build_meta"
+
+[tool.black]
+line-length = 79
+target-version = ["py36"]
+
+[tool.pytest.ini_options]
+addopts = "-r s --capture=no --strict-markers --benchmark-disable"
+markers = [
+    "skip_fips: this test is not executed in FIPS mode",
+    "supported: parametrized test requiring only_if and skip_message",
+]
+
+[tool.mypy]
+show_error_codes = true
+check_untyped_defs = true
+no_implicit_reexport = true
+warn_redundant_casts = true
+warn_unused_ignores = true
+warn_unused_configs = true
+strict_equality = true
+
+[[tool.mypy.overrides]]
+module = [
+    "pretend"
+]
+ignore_missing_imports = true
+
+[tool.coverage.run]
+branch = true
+relative_files = true
+source = [
+    "cryptography",
+    "tests/",
+]
+
+[tool.coverage.paths]
+source = [
+   "src/cryptography",
+   "*.tox/*/lib*/python*/site-packages/cryptography",
+   "*.tox\\*\\Lib\\site-packages\\cryptography",
+   "*.tox/pypy/site-packages/cryptography",
+]
+tests =[
+   "tests/",
+   "*tests\\",
+]
+
+[tool.coverage.report]
+exclude_lines = [
+    "@abc.abstractmethod",
+    "@abc.abstractproperty",
+    "@typing.overload",
+    "if typing.TYPE_CHECKING",
+]

flake8_to_ruff/examples/cryptography/setup.cfg

@@ -0,0 +1,91 @@
+[metadata]
+name = cryptography
+version = attr: cryptography.__version__
+description = cryptography is a package which provides cryptographic recipes and primitives to Python developers.
+long_description = file: README.rst
+long_description_content_type = text/x-rst
+license = BSD-3-Clause OR Apache-2.0
+url = https://github.com/pyca/cryptography
+author = The Python Cryptographic Authority and individual contributors
+author_email = cryptography-dev@python.org
+project_urls =
+    Documentation=https://cryptography.io/
+    Source=https://github.com/pyca/cryptography/
+    Issues=https://github.com/pyca/cryptography/issues
+    Changelog=https://cryptography.io/en/latest/changelog/
+classifiers =
+    Development Status :: 5 - Production/Stable
+    Intended Audience :: Developers
+    License :: OSI Approved :: Apache Software License
+    License :: OSI Approved :: BSD License
+    Natural Language :: English
+    Operating System :: MacOS :: MacOS X
+    Operating System :: POSIX
+    Operating System :: POSIX :: BSD
+    Operating System :: POSIX :: Linux
+    Operating System :: Microsoft :: Windows
+    Programming Language :: Python
+    Programming Language :: Python :: 3
+    Programming Language :: Python :: 3 :: Only
+    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
+    Programming Language :: Python :: 3.9
+    Programming Language :: Python :: 3.10
+    Programming Language :: Python :: 3.11
+    Programming Language :: Python :: Implementation :: CPython
+    Programming Language :: Python :: Implementation :: PyPy
+    Topic :: Security :: Cryptography
+
+[options]
+python_requires = >=3.6
+include_package_data = True
+zip_safe = False
+package_dir =
+    =src
+packages = find:
+# `install_requires` must be kept in sync with `pyproject.toml`
+install_requires =
+    cffi >=1.12
+
+[options.packages.find]
+where = src
+exclude =
+    _cffi_src
+    _cffi_src.*
+
+[options.extras_require]
+test =
+    pytest>=6.2.0
+    pytest-benchmark
+    pytest-cov
+    pytest-subtests
+    pytest-xdist
+    pretend
+    iso8601
+    pytz
+    hypothesis>=1.11.4,!=3.79.2
+docs =
+    sphinx >= 1.6.5,!=1.8.0,!=3.1.0,!=3.1.1,!=5.2.0,!=5.2.0.post0
+    sphinx_rtd_theme
+docstest =
+    pyenchant >= 1.6.11
+    twine >= 1.12.0
+    sphinxcontrib-spelling >= 4.0.1
+sdist =
+    setuptools_rust >= 0.11.4
+pep8test =
+    black
+    flake8
+    flake8-import-order
+    pep8-naming
+# This extra is for OpenSSH private keys that use bcrypt KDF
+# Versions: v3.1.3 - ignore_few_rounds, v3.1.5 - abi3
+ssh =
+    bcrypt >= 3.1.5
+
+[flake8]
+ignore = E203,E211,W503,W504,N818
+exclude = .tox,*.egg,.git,_build,.hypothesis
+select = E,W,F,N,I
+application-import-names = cryptography,cryptography_vectors,tests

flake8_to_ruff/pyproject.toml

@@ -12,6 +12,7 @@ classifiers = [
     "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3 :: Only",
     "Topic :: Software Development :: Libraries :: Python Modules",
     "Topic :: Software Development :: Quality Assurance",

flake8_to_ruff/src/black.rs

@@ -0,0 +1,32 @@
+//! Extract Black configuration settings from a pyproject.toml.
+
+use std::path::Path;
+
+use anyhow::Result;
+use ruff::settings::types::PythonVersion;
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Default)]
+pub struct Black {
+    #[serde(alias = "line-length", alias = "line_length")]
+    pub line_length: Option<usize>,
+    #[serde(alias = "target-version", alias = "target_version")]
+    pub target_version: Option<Vec<PythonVersion>>,
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
+struct Tools {
+    black: Option<Black>,
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
+struct Pyproject {
+    tool: Option<Tools>,
+}
+
+pub fn parse_black_options<P: AsRef<Path>>(path: P) -> Result<Option<Black>> {
+    let contents = std::fs::read_to_string(path)?;
+    Ok(toml::from_str::<Pyproject>(&contents)?
+        .tool
+        .and_then(|tool| tool.black))
+}

flake8_to_ruff/src/converter.rs

@@ -7,16 +7,24 @@ use ruff::flake8_tidy_imports::settings::Strictness;
 use ruff::settings::options::Options;
 use ruff::settings::pyproject::Pyproject;
 use ruff::{
-    flake8_annotations, flake8_bugbear, flake8_quotes, flake8_tidy_imports, mccabe, pep8_naming,
+    flake8_annotations, flake8_bugbear, flake8_errmsg, flake8_quotes, flake8_tidy_imports, mccabe,
+    pep8_naming,
 };
 
+use crate::black::Black;
 use crate::plugin::Plugin;
 use crate::{parser, plugin};
 
 pub fn convert(
-    flake8: &HashMap<String, Option<String>>,
+    config: &HashMap<String, HashMap<String, Option<String>>>,
+    black: Option<&Black>,
     plugins: Option<Vec<Plugin>>,
 ) -> Result<Pyproject> {
+    // Extract the Flake8 section.
+    let flake8 = config
+        .get("flake8")
+        .expect("Unable to find flake8 section in INI file");
+
     // Extract all referenced check code prefixes, to power plugin inference.
     let mut referenced_codes: BTreeSet<CheckCodePrefix> = BTreeSet::default();
     for (key, value) in flake8 {
@@ -53,10 +61,15 @@ pub fn convert(
             plugin::resolve_select(
                 flake8,
                 &plugins.unwrap_or_else(|| {
-                    plugin::infer_plugins_from_options(flake8)
-                        .into_iter()
-                        .chain(plugin::infer_plugins_from_codes(&referenced_codes))
-                        .collect()
+                    let from_options = plugin::infer_plugins_from_options(flake8);
+                    if !from_options.is_empty() {
+                        eprintln!("Inferred plugins from settings: {from_options:#?}");
+                    }
+                    let from_codes = plugin::infer_plugins_from_codes(&referenced_codes);
+                    if !from_codes.is_empty() {
+                        eprintln!("Inferred plugins from referenced check codes: {from_codes:#?}");
+                    }
+                    from_options.into_iter().chain(from_codes).collect()
                 }),
             )
         });
@@ -73,6 +86,7 @@ pub fn convert(
     let mut options = Options::default();
     let mut flake8_annotations = flake8_annotations::settings::Options::default();
     let mut flake8_bugbear = flake8_bugbear::settings::Options::default();
+    let mut flake8_errmsg = flake8_errmsg::settings::Options::default();
     let mut flake8_quotes = flake8_quotes::settings::Options::default();
     let mut flake8_tidy_imports = flake8_tidy_imports::settings::Options::default();
     let mut mccabe = mccabe::settings::Options::default();
@@ -194,6 +208,15 @@ pub fn convert(
                     Ok(max_complexity) => mccabe.max_complexity = Some(max_complexity),
                     Err(e) => eprintln!("Unable to parse '{key}' property: {e}"),
                 },
+                // flake8-errmsg
+                "errmsg-max-string-length" | "errmsg_max_string_length" => {
+                    match value.clone().parse::<usize>() {
+                        Ok(max_string_length) => {
+                            flake8_errmsg.max_string_length = Some(max_string_length);
+                        }
+                        Err(e) => eprintln!("Unable to parse '{key}' property: {e}"),
+                    }
+                }
                 // Unknown
                 _ => eprintln!("Skipping unsupported property: {key}"),
             }
@@ -209,6 +232,9 @@ pub fn convert(
     if flake8_bugbear != flake8_bugbear::settings::Options::default() {
         options.flake8_bugbear = Some(flake8_bugbear);
     }
+    if flake8_errmsg != flake8_errmsg::settings::Options::default() {
+        options.flake8_errmsg = Some(flake8_errmsg);
+    }
     if flake8_quotes != flake8_quotes::settings::Options::default() {
         options.flake8_quotes = Some(flake8_quotes);
     }
@@ -222,6 +248,19 @@ pub fn convert(
         options.pep8_naming = Some(pep8_naming);
     }
 
+    // Extract any settings from the existing `pyproject.toml`.
+    if let Some(black) = black {
+        if let Some(line_length) = &black.line_length {
+            options.line_length = Some(*line_length);
+        }
+
+        if let Some(target_version) = &black.target_version {
+            if let Some(target_version) = target_version.iter().min() {
+                options.target_version = Some(*target_version);
+            }
+        }
+    }
+
     // Create the pyproject.toml.
     Ok(Pyproject::new(options))
 }
@@ -241,7 +280,11 @@ mod tests {
 
     #[test]
     fn it_converts_empty() -> Result<()> {
-        let actual = convert(&HashMap::from([]), None)?;
+        let actual = convert(
+            &HashMap::from([("flake8".to_string(), HashMap::default())]),
+            None,
+            None,
+        )?;
         let expected = Pyproject::new(Options {
             allowed_confusables: None,
             dummy_variable_rgx: None,
@@ -254,6 +297,7 @@ mod tests {
             fix: None,
             fixable: None,
             format: None,
+            force_exclude: None,
             ignore: Some(vec![]),
             ignore_init_module_imports: None,
             line_length: None,
@@ -268,11 +312,14 @@ mod tests {
             src: None,
             target_version: None,
             unfixable: None,
+            cache_dir: None,
             flake8_annotations: None,
             flake8_bugbear: None,
+            flake8_errmsg: None,
             flake8_quotes: None,
             flake8_tidy_imports: None,
             flake8_import_conventions: None,
+            flake8_unused_arguments: None,
             isort: None,
             mccabe: None,
             pep8_naming: None,
@@ -286,7 +333,11 @@ mod tests {
     #[test]
     fn it_converts_dashes() -> Result<()> {
         let actual = convert(
-            &HashMap::from([("max-line-length".to_string(), Some("100".to_string()))]),
+            &HashMap::from([(
+                "flake8".to_string(),
+                HashMap::from([("max-line-length".to_string(), Some("100".to_string()))]),
+            )]),
+            None,
             Some(vec![]),
         )?;
         let expected = Pyproject::new(Options {
@@ -301,6 +352,7 @@ mod tests {
             fix: None,
             fixable: None,
             format: None,
+            force_exclude: None,
             ignore: Some(vec![]),
             ignore_init_module_imports: None,
             line_length: Some(100),
@@ -315,11 +367,14 @@ mod tests {
             src: None,
             target_version: None,
             unfixable: None,
+            cache_dir: None,
             flake8_annotations: None,
             flake8_bugbear: None,
+            flake8_errmsg: None,
             flake8_quotes: None,
             flake8_tidy_imports: None,
             flake8_import_conventions: None,
+            flake8_unused_arguments: None,
             isort: None,
             mccabe: None,
             pep8_naming: None,
@@ -333,7 +388,11 @@ mod tests {
     #[test]
     fn it_converts_underscores() -> Result<()> {
         let actual = convert(
-            &HashMap::from([("max_line_length".to_string(), Some("100".to_string()))]),
+            &HashMap::from([(
+                "flake8".to_string(),
+                HashMap::from([("max_line_length".to_string(), Some("100".to_string()))]),
+            )]),
+            None,
             Some(vec![]),
         )?;
         let expected = Pyproject::new(Options {
@@ -348,6 +407,7 @@ mod tests {
             fix: None,
             fixable: None,
             format: None,
+            force_exclude: None,
             ignore: Some(vec![]),
             ignore_init_module_imports: None,
             line_length: Some(100),
@@ -362,11 +422,14 @@ mod tests {
             src: None,
             target_version: None,
             unfixable: None,
+            cache_dir: None,
             flake8_annotations: None,
             flake8_bugbear: None,
+            flake8_errmsg: None,
             flake8_quotes: None,
             flake8_tidy_imports: None,
             flake8_import_conventions: None,
+            flake8_unused_arguments: None,
             isort: None,
             mccabe: None,
             pep8_naming: None,
@@ -380,7 +443,11 @@ mod tests {
     #[test]
     fn it_ignores_parse_errors() -> Result<()> {
         let actual = convert(
-            &HashMap::from([("max_line_length".to_string(), Some("abc".to_string()))]),
+            &HashMap::from([(
+                "flake8".to_string(),
+                HashMap::from([("max_line_length".to_string(), Some("abc".to_string()))]),
+            )]),
+            None,
             Some(vec![]),
         )?;
         let expected = Pyproject::new(Options {
@@ -395,6 +462,7 @@ mod tests {
             fix: None,
             fixable: None,
             format: None,
+            force_exclude: None,
             ignore: Some(vec![]),
             ignore_init_module_imports: None,
             line_length: None,
@@ -409,11 +477,14 @@ mod tests {
             src: None,
             target_version: None,
             unfixable: None,
+            cache_dir: None,
             flake8_annotations: None,
             flake8_bugbear: None,
+            flake8_errmsg: None,
             flake8_quotes: None,
             flake8_tidy_imports: None,
             flake8_import_conventions: None,
+            flake8_unused_arguments: None,
             isort: None,
             mccabe: None,
             pep8_naming: None,
@@ -427,7 +498,11 @@ mod tests {
     #[test]
     fn it_converts_plugin_options() -> Result<()> {
         let actual = convert(
-            &HashMap::from([("inline-quotes".to_string(), Some("single".to_string()))]),
+            &HashMap::from([(
+                "flake8".to_string(),
+                HashMap::from([("inline-quotes".to_string(), Some("single".to_string()))]),
+            )]),
+            None,
             Some(vec![]),
         )?;
         let expected = Pyproject::new(Options {
@@ -442,6 +517,7 @@ mod tests {
             fix: None,
             fixable: None,
             format: None,
+            force_exclude: None,
             ignore: Some(vec![]),
             ignore_init_module_imports: None,
             line_length: None,
@@ -456,8 +532,10 @@ mod tests {
             src: None,
             target_version: None,
             unfixable: None,
+            cache_dir: None,
             flake8_annotations: None,
             flake8_bugbear: None,
+            flake8_errmsg: None,
             flake8_quotes: Some(flake8_quotes::settings::Options {
                 inline_quotes: Some(flake8_quotes::settings::Quote::Single),
                 multiline_quotes: None,
@@ -466,6 +544,7 @@ mod tests {
             }),
             flake8_tidy_imports: None,
             flake8_import_conventions: None,
+            flake8_unused_arguments: None,
             isort: None,
             mccabe: None,
             pep8_naming: None,
@@ -480,9 +559,13 @@ mod tests {
     fn it_converts_docstring_conventions() -> Result<()> {
         let actual = convert(
             &HashMap::from([(
-                "docstring-convention".to_string(),
-                Some("numpy".to_string()),
+                "flake8".to_string(),
+                HashMap::from([(
+                    "docstring-convention".to_string(),
+                    Some("numpy".to_string()),
+                )]),
             )]),
+            None,
             Some(vec![Plugin::Flake8Docstrings]),
         )?;
         let expected = Pyproject::new(Options {
@@ -497,6 +580,7 @@ mod tests {
             fix: None,
             fixable: None,
             format: None,
+            force_exclude: None,
             ignore: Some(vec![]),
             ignore_init_module_imports: None,
             line_length: None,
@@ -547,11 +631,14 @@ mod tests {
             src: None,
             target_version: None,
             unfixable: None,
+            cache_dir: None,
             flake8_annotations: None,
             flake8_bugbear: None,
+            flake8_errmsg: None,
             flake8_quotes: None,
             flake8_tidy_imports: None,
             flake8_import_conventions: None,
+            flake8_unused_arguments: None,
             isort: None,
             mccabe: None,
             pep8_naming: None,
@@ -565,7 +652,11 @@ mod tests {
     #[test]
     fn it_infers_plugins_if_omitted() -> Result<()> {
         let actual = convert(
-            &HashMap::from([("inline-quotes".to_string(), Some("single".to_string()))]),
+            &HashMap::from([(
+                "flake8".to_string(),
+                HashMap::from([("inline-quotes".to_string(), Some("single".to_string()))]),
+            )]),
+            None,
             None,
         )?;
         let expected = Pyproject::new(Options {
@@ -580,6 +671,7 @@ mod tests {
             fix: None,
             fixable: None,
             format: None,
+            force_exclude: None,
             ignore: Some(vec![]),
             ignore_init_module_imports: None,
             line_length: None,
@@ -595,8 +687,10 @@ mod tests {
             src: None,
             target_version: None,
             unfixable: None,
+            cache_dir: None,
             flake8_annotations: None,
             flake8_bugbear: None,
+            flake8_errmsg: None,
             flake8_quotes: Some(flake8_quotes::settings::Options {
                 inline_quotes: Some(flake8_quotes::settings::Quote::Single),
                 multiline_quotes: None,
@@ -605,6 +699,7 @@ mod tests {
             }),
             flake8_tidy_imports: None,
             flake8_import_conventions: None,
+            flake8_unused_arguments: None,
             isort: None,
             mccabe: None,
             pep8_naming: None,

flake8_to_ruff/src/lib.rs

@@ -11,6 +11,7 @@
     clippy::too_many_lines
 )]
 
+pub mod black;
 pub mod converter;
 mod parser;
 pub mod plugin;

flake8_to_ruff/src/main.rs

@@ -17,6 +17,7 @@ use std::path::PathBuf;
 use anyhow::Result;
 use clap::Parser;
 use configparser::ini::Ini;
+use flake8_to_ruff::black::parse_black_options;
 use flake8_to_ruff::converter;
 use flake8_to_ruff::plugin::Plugin;
 
@@ -26,10 +27,14 @@ use flake8_to_ruff::plugin::Plugin;
     long_about = None
 )]
 struct Cli {
-    /// Path to the Flake8 configuration file (e.g., 'setup.cfg', 'tox.ini', or
-    /// '.flake8').
+    /// Path to the Flake8 configuration file (e.g., `setup.cfg`, `tox.ini`, or
+    /// `.flake8`).
     #[arg(required = true)]
     file: PathBuf,
+    /// Optional path to a `pyproject.toml` file, used to ensure compatibility
+    /// with Black.
+    #[arg(long)]
+    pyproject: Option<PathBuf>,
     /// List of plugins to enable.
     #[arg(long, value_delimiter = ',')]
     plugin: Option<Vec<Plugin>>,
@@ -43,13 +48,15 @@ fn main() -> Result<()> {
     ini.set_multiline(true);
     let config = ini.load(cli.file).map_err(|msg| anyhow::anyhow!(msg))?;
 
-    // Extract the Flake8 section.
-    let flake8 = config
-        .get("flake8")
-        .expect("Unable to find flake8 section in INI file");
+    // Read the pyproject.toml file.
+    let black = cli
+        .pyproject
+        .map(parse_black_options)
+        .transpose()?
+        .flatten();
 
-    // Create the pyproject.toml.
-    let pyproject = converter::convert(flake8, cli.plugin)?;
+    // Create Ruff's pyproject.toml section.
+    let pyproject = converter::convert(&config, black.as_ref(), cli.plugin)?;
     println!("{}", toml::to_string_pretty(&pyproject)?);
 
     Ok(())

flake8_to_ruff/src/parser.rs

@@ -3,6 +3,7 @@ use std::str::FromStr;
 use anyhow::{bail, Result};
 use once_cell::sync::Lazy;
 use regex::Regex;
+use ruff::checks::PREFIX_REDIRECTS;
 use ruff::checks_gen::CheckCodePrefix;
 use ruff::settings::types::PatternPrefixPair;
 use rustc_hash::FxHashMap;
@@ -18,7 +19,9 @@ pub fn parse_prefix_codes(value: &str) -> Vec<CheckCodePrefix> {
         if code.is_empty() {
             continue;
         }
-        if let Ok(code) = CheckCodePrefix::from_str(code) {
+        if let Some(code) = PREFIX_REDIRECTS.get(code) {
+            codes.push(code.clone());
+        } else if let Ok(code) = CheckCodePrefix::from_str(code) {
             codes.push(code);
         } else {
             eprintln!("Unsupported prefix code: {code}");
@@ -83,16 +86,22 @@ impl State {
     fn parse(&self) -> Vec<PatternPrefixPair> {
         let mut codes: Vec<PatternPrefixPair> = vec![];
         for code in &self.codes {
-            match CheckCodePrefix::from_str(code) {
-                Ok(code) => {
-                    for filename in &self.filenames {
-                        codes.push(PatternPrefixPair {
-                            pattern: filename.clone(),
-                            prefix: code.clone(),
-                        });
-                    }
+            if let Some(code) = PREFIX_REDIRECTS.get(code.as_str()) {
+                for filename in &self.filenames {
+                    codes.push(PatternPrefixPair {
+                        pattern: filename.clone(),
+                        prefix: code.clone(),
+                    });
                 }
-                Err(_) => eprintln!("Skipping unrecognized prefix: {code}"),
+            } else if let Ok(code) = CheckCodePrefix::from_str(code) {
+                for filename in &self.filenames {
+                    codes.push(PatternPrefixPair {
+                        pattern: filename.clone(),
+                        prefix: code.clone(),
+                    });
+                }
+            } else {
+                eprintln!("Unsupported prefix code: {code}");
             }
         }
         codes

flake8_to_ruff/src/plugin.rs

@@ -1,10 +1,11 @@
 use std::collections::{BTreeSet, HashMap};
+use std::fmt;
 use std::str::FromStr;
 
 use anyhow::anyhow;
 use ruff::checks_gen::CheckCodePrefix;
 
-#[derive(Debug, Clone, Ord, PartialOrd, Eq, PartialEq)]
+#[derive(Clone, Ord, PartialOrd, Eq, PartialEq)]
 pub enum Plugin {
     Flake8Annotations,
     Flake8Bandit,
@@ -12,8 +13,10 @@ pub enum Plugin {
     Flake8Bugbear,
     Flake8Builtins,
     Flake8Comprehensions,
+    Flake8Datetimez,
     Flake8Debugger,
     Flake8Docstrings,
+    Flake8ErrMsg,
     Flake8Eradicate,
     Flake8Print,
     Flake8Quotes,
@@ -21,6 +24,7 @@ pub enum Plugin {
     Flake8Simplify,
     Flake8TidyImports,
     McCabe,
+    PandasVet,
     PEP8Naming,
     Pyupgrade,
 }
@@ -36,15 +40,18 @@ impl FromStr for Plugin {
             "flake8-bugbear" => Ok(Plugin::Flake8Bugbear),
             "flake8-builtins" => Ok(Plugin::Flake8Builtins),
             "flake8-comprehensions" => Ok(Plugin::Flake8Comprehensions),
+            "flake8-datetimez" => Ok(Plugin::Flake8Datetimez),
             "flake8-debugger" => Ok(Plugin::Flake8Debugger),
             "flake8-docstrings" => Ok(Plugin::Flake8Docstrings),
-            "flake8-eradicate" => Ok(Plugin::Flake8BlindExcept),
+            "flake8-eradicate" => Ok(Plugin::Flake8Eradicate),
+            "flake8-errmsg" => Ok(Plugin::Flake8ErrMsg),
             "flake8-print" => Ok(Plugin::Flake8Print),
             "flake8-quotes" => Ok(Plugin::Flake8Quotes),
             "flake8-return" => Ok(Plugin::Flake8Return),
             "flake8-simplify" => Ok(Plugin::Flake8Simplify),
             "flake8-tidy-imports" => Ok(Plugin::Flake8TidyImports),
             "mccabe" => Ok(Plugin::McCabe),
+            "pandas-vet" => Ok(Plugin::PandasVet),
             "pep8-naming" => Ok(Plugin::PEP8Naming),
             "pyupgrade" => Ok(Plugin::Pyupgrade),
             _ => Err(anyhow!("Unknown plugin: {string}")),
@@ -52,26 +59,62 @@ impl FromStr for Plugin {
     }
 }
 
+impl fmt::Debug for Plugin {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            f,
+            "{}",
+            match self {
+                Plugin::Flake8Annotations => "flake8-annotations",
+                Plugin::Flake8Bandit => "flake8-bandit",
+                Plugin::Flake8BlindExcept => "flake8-blind-except",
+                Plugin::Flake8Bugbear => "flake8-bugbear",
+                Plugin::Flake8Builtins => "flake8-builtins",
+                Plugin::Flake8Comprehensions => "flake8-comprehensions",
+                Plugin::Flake8Datetimez => "flake8-datetimez",
+                Plugin::Flake8Debugger => "flake8-debugger",
+                Plugin::Flake8Docstrings => "flake8-docstrings",
+                Plugin::Flake8Eradicate => "flake8-eradicate",
+                Plugin::Flake8ErrMsg => "flake8-errmsg",
+                Plugin::Flake8Print => "flake8-print",
+                Plugin::Flake8Quotes => "flake8-quotes",
+                Plugin::Flake8Return => "flake8-return",
+                Plugin::Flake8Simplify => "flake8-simplify",
+                Plugin::Flake8TidyImports => "flake8-tidy-imports",
+                Plugin::McCabe => "mccabe",
+                Plugin::PandasVet => "pandas-vet",
+                Plugin::PEP8Naming => "pep8-naming",
+                Plugin::Pyupgrade => "pyupgrade",
+            }
+        )
+    }
+}
+
 impl Plugin {
     pub fn default(&self) -> CheckCodePrefix {
         match self {
             Plugin::Flake8Annotations => CheckCodePrefix::ANN,
             Plugin::Flake8Bandit => CheckCodePrefix::S,
+            // TODO(charlie): Handle rename of `B` to `BLE`.
             Plugin::Flake8BlindExcept => CheckCodePrefix::BLE,
             Plugin::Flake8Bugbear => CheckCodePrefix::B,
             Plugin::Flake8Builtins => CheckCodePrefix::A,
             Plugin::Flake8Comprehensions => CheckCodePrefix::C4,
+            Plugin::Flake8Datetimez => CheckCodePrefix::DTZ,
             Plugin::Flake8Debugger => CheckCodePrefix::T1,
             Plugin::Flake8Docstrings => CheckCodePrefix::D,
+            // TODO(charlie): Handle rename of `E` to `ERA`.
             Plugin::Flake8Eradicate => CheckCodePrefix::ERA,
+            Plugin::Flake8ErrMsg => CheckCodePrefix::EM,
             Plugin::Flake8Print => CheckCodePrefix::T2,
             Plugin::Flake8Quotes => CheckCodePrefix::Q,
             Plugin::Flake8Return => CheckCodePrefix::RET,
             Plugin::Flake8Simplify => CheckCodePrefix::SIM,
-            Plugin::Flake8TidyImports => CheckCodePrefix::I25,
+            Plugin::Flake8TidyImports => CheckCodePrefix::TID25,
             Plugin::McCabe => CheckCodePrefix::C9,
+            Plugin::PandasVet => CheckCodePrefix::PD,
             Plugin::PEP8Naming => CheckCodePrefix::N,
-            Plugin::Pyupgrade => CheckCodePrefix::U,
+            Plugin::Pyupgrade => CheckCodePrefix::UP,
         }
     }
 
@@ -83,6 +126,7 @@ impl Plugin {
             Plugin::Flake8Bugbear => vec![CheckCodePrefix::B],
             Plugin::Flake8Builtins => vec![CheckCodePrefix::A],
             Plugin::Flake8Comprehensions => vec![CheckCodePrefix::C4],
+            Plugin::Flake8Datetimez => vec![CheckCodePrefix::DTZ],
             Plugin::Flake8Debugger => vec![CheckCodePrefix::T1],
             Plugin::Flake8Docstrings => {
                 // Use the user-provided docstring.
@@ -101,14 +145,16 @@ impl Plugin {
                 DocstringConvention::PEP8.select()
             }
             Plugin::Flake8Eradicate => vec![CheckCodePrefix::ERA],
+            Plugin::Flake8ErrMsg => vec![CheckCodePrefix::EM],
             Plugin::Flake8Print => vec![CheckCodePrefix::T2],
             Plugin::Flake8Quotes => vec![CheckCodePrefix::Q],
             Plugin::Flake8Return => vec![CheckCodePrefix::RET],
             Plugin::Flake8Simplify => vec![CheckCodePrefix::SIM],
-            Plugin::Flake8TidyImports => vec![CheckCodePrefix::I25],
+            Plugin::Flake8TidyImports => vec![CheckCodePrefix::TID],
             Plugin::McCabe => vec![CheckCodePrefix::C9],
+            Plugin::PandasVet => vec![CheckCodePrefix::PD],
             Plugin::PEP8Naming => vec![CheckCodePrefix::N],
-            Plugin::Pyupgrade => vec![CheckCodePrefix::U],
+            Plugin::Pyupgrade => vec![CheckCodePrefix::UP],
         }
     }
 }
@@ -377,6 +423,9 @@ pub fn infer_plugins_from_options(flake8: &HashMap<String, Option<String>>) -> V
             "staticmethod-decorators" | "staticmethod_decorators" => {
                 plugins.insert(Plugin::PEP8Naming);
             }
+            "max-string-length" | "max_string_length" => {
+                plugins.insert(Plugin::Flake8ErrMsg);
+            }
             _ => {}
         }
     }
@@ -395,16 +444,18 @@ pub fn infer_plugins_from_codes(codes: &BTreeSet<CheckCodePrefix>) -> Vec<Plugin
         Plugin::Flake8Bugbear,
         Plugin::Flake8Builtins,
         Plugin::Flake8Comprehensions,
+        Plugin::Flake8Datetimez,
         Plugin::Flake8Debugger,
         Plugin::Flake8Docstrings,
         Plugin::Flake8Eradicate,
+        Plugin::Flake8ErrMsg,
         Plugin::Flake8Print,
         Plugin::Flake8Quotes,
         Plugin::Flake8Return,
         Plugin::Flake8Simplify,
         Plugin::Flake8TidyImports,
+        Plugin::PandasVet,
         Plugin::PEP8Naming,
-        Plugin::Pyupgrade,
     ]
     .into_iter()
     .filter(|plugin| {

pyproject.toml

@@ -12,6 +12,7 @@ classifiers = [
     "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3 :: Only",
     "Topic :: Software Development :: Libraries :: Python Modules",
     "Topic :: Software Development :: Quality Assurance",
@@ -32,6 +33,8 @@ build-backend = "maturin"
 bindings = "bin"
 strip = true
 
+[tool.ruff]
+
 [tool.ruff.isort]
 force-wrap-aliases = true
 combine-as-imports = true

resources/test/fixtures/flake8_boolean_trap/FBT.py

@@ -55,3 +55,5 @@ a.get("hello", False)
 {}.pop(True, False)
 dict.fromkeys(("world",), True)
 {}.deploy(True, False)
+getattr(someobj, attrname, False)
+mylist.index(True)

resources/test/fixtures/flake8_datetimez/DTZ001.py

@@ -0,0 +1,21 @@
+import datetime
+
+# no args
+datetime.datetime(2000, 1, 1, 0, 0, 0)
+
+# none args
+datetime.datetime(2000, 1, 1, 0, 0, 0, 0, None)
+
+# not none arg
+datetime.datetime(2000, 1, 1, 0, 0, 0, 0, datetime.timezone.utc)
+
+# no kwargs
+datetime.datetime(2000, 1, 1, fold=1)
+
+# none kwargs
+datetime.datetime(2000, 1, 1, tzinfo=None)
+
+from datetime import datetime
+
+# no args unqualified
+datetime(2000, 1, 1, 0, 0, 0)

resources/test/fixtures/flake8_datetimez/DTZ002.py

@@ -0,0 +1,9 @@
+import datetime
+
+# qualified
+datetime.datetime.today()
+
+from datetime import datetime
+
+# unqualified
+datetime.today()

resources/test/fixtures/flake8_datetimez/DTZ003.py

@@ -0,0 +1,9 @@
+import datetime
+
+# qualified
+datetime.datetime.utcnow()
+
+from datetime import datetime
+
+# unqualified
+datetime.utcnow()

resources/test/fixtures/flake8_datetimez/DTZ004.py

@@ -0,0 +1,9 @@
+import datetime
+
+# qualified
+datetime.datetime.utcfromtimestamp(1234)
+
+from datetime import datetime
+
+# unqualified
+datetime.utcfromtimestamp(1234)

resources/test/fixtures/flake8_datetimez/DTZ005.py

@@ -0,0 +1,18 @@
+import datetime
+
+# no args
+datetime.datetime.now()
+
+# wrong keywords
+datetime.datetime.now(bad=datetime.timezone.utc)
+
+# none args
+datetime.datetime.now(None)
+
+# none keywords
+datetime.datetime.now(tz=None)
+
+from datetime import datetime
+
+# no args unqualified
+datetime.now()

resources/test/fixtures/flake8_datetimez/DTZ006.py

@@ -0,0 +1,18 @@
+import datetime
+
+# no args
+datetime.datetime.fromtimestamp(1234)
+
+# wrong keywords
+datetime.datetime.fromtimestamp(1234, bad=datetime.timezone.utc)
+
+# none args
+datetime.datetime.fromtimestamp(1234, None)
+
+# none keywords
+datetime.datetime.fromtimestamp(1234, tz=None)
+
+from datetime import datetime
+
+# no args unqualified
+datetime.fromtimestamp(1234)

resources/test/fixtures/flake8_datetimez/DTZ007.py

@@ -0,0 +1,35 @@
+import datetime
+
+# bad format
+datetime.datetime.strptime("something", "%H:%M:%S%Z")
+
+# no replace or astimezone
+datetime.datetime.strptime("something", "something")
+
+# wrong replace
+datetime.datetime.strptime("something", "something").replace(hour=1)
+
+# none replace
+datetime.datetime.strptime("something", "something").replace(tzinfo=None)
+
+# OK
+datetime.datetime.strptime("something", "something").replace(
+    tzinfo=datetime.timezone.utc
+)
+
+# OK
+datetime.datetime.strptime("something", "something").astimezone()
+
+# OK
+datetime.datetime.strptime("something", "%H:%M:%S%z")
+
+# OK
+datetime.datetime.strptime("something", something).astimezone()
+
+# OK
+datetime.datetime.strptime("something", something).replace(tzinfo=datetime.timezone.utc)
+
+from datetime import datetime
+
+# no replace orastimezone unqualified
+datetime.strptime("something", "something")

resources/test/fixtures/flake8_datetimez/DTZ011.py

@@ -0,0 +1,9 @@
+import datetime
+
+# qualified
+datetime.date.today()
+
+from datetime import date
+
+# unqualified
+date.today()

resources/test/fixtures/flake8_datetimez/DTZ012.py

@@ -0,0 +1,9 @@
+import datetime
+
+# qualified
+datetime.date.fromtimestamp(1234)
+
+from datetime import date
+
+# unqualified
+date.fromtimestamp(1234)

resources/test/fixtures/flake8_debugger/T100.py

@@ -1,6 +1,5 @@
 breakpoint()
 
-
 import pdb
 import builtins
 from builtins import breakpoint
@@ -9,7 +8,6 @@ from celery.contrib.rdb import set_trace
 from celery.contrib import rdb
 import celery.contrib.rdb
 
-
 breakpoint()
 st()
 set_trace()

resources/test/fixtures/flake8_errmsg/EM.py

@@ -0,0 +1,23 @@
+from __future__ import annotations
+
+
+def f_a():
+    raise RuntimeError("This is an example exception")
+
+
+def f_a_short():
+    raise RuntimeError("Error")
+
+
+def f_b():
+    example = "example"
+    raise RuntimeError(f"This is an {example} exception")
+
+
+def f_c():
+    raise RuntimeError("This is an {example} exception".format(example="example"))
+
+
+def f_ok():
+    msg = "hello"
+    raise RuntimeError(msg)

resources/test/fixtures/flake8_print/T201.py

@@ -1 +1,10 @@
+import sys
+import tempfile
+
 print("Hello, world!")  # T201
+print("Hello, world!", file=None)  # T201
+print("Hello, world!", file=sys.stdout)  # T201
+print("Hello, world!", file=sys.stderr)  # T201
+
+with tempfile.NamedTemporaryFile() as fp:
+    print("Hello, world!", file=fp)  # OK

resources/test/fixtures/flake8_print/T203.py

@@ -2,7 +2,6 @@ from pprint import pprint
 
 pprint("Hello, world!")  # T203
 
-
 import pprint
 
 pprint.pprint("Hello, world!")  # T203

resources/test/fixtures/flake8_return/RET504.py

@@ -6,18 +6,6 @@ def x():
     return a  # error
 
 
-def x():
-    b, a = 1, 2
-    print(b)
-    return a  # error
-
-
-def x():
-    a = 1
-    print()
-    return a  # error
-
-
 def x():
     a = 1
     print(a)
@@ -53,7 +41,6 @@ def x():
 
 # https://github.com/afonasev/flake8-return/issues/47#issue-641117366
 def user_agent_username(username=None):
-
     if not username:
         return ""
 
@@ -136,6 +123,20 @@ def x():
     return a
 
 
+# Considered OK, since functions can have side effects.
+def x():
+    b, a = 1, 2
+    print(b)
+    return a
+
+
+# Considered OK, since functions can have side effects.
+def x():
+    a = 1
+    print()
+    return a
+
+
 # Test cases for using value for assignment then returning it
 # See:https://github.com/afonasev/flake8-return/issues/47
 def resolve_from_url(self, url: str) -> dict:
@@ -236,3 +237,15 @@ def close(self):
             any_failed = True
             report(traceback.format_exc())
     return any_failed
+
+def global_assignment():
+    global X
+    X = 1
+    return X
+
+def nonlocal_assignment():
+    X = 1
+    def inner():
+        nonlocal X
+        X = 1
+        return X

resources/test/fixtures/flake8_unused_arguments/ARG.py

@@ -27,7 +27,7 @@ def f(cls, x):
 lambda x: print("Hello, world!")
 
 
-class X:
+class C:
     ###
     # Unused arguments.
     ###

resources/test/fixtures/flake8_unused_arguments/ignore_variadic_names.py

@@ -0,0 +1,14 @@
+def f(a, b):
+    print("Hello, world!")
+
+
+def f(a, b, *args, **kwargs):
+    print("Hello, world!")
+
+
+class C:
+    def f(self, a, b):
+        print("Hello, world!")
+
+    def f(self, a, b, *args, **kwargs):
+        print("Hello, world!")

resources/test/fixtures/isort/leading_prefix.py

@@ -4,3 +4,10 @@ import os
 if True:
     x = 1; import sys
     import os
+
+if True:
+    x = 1; \
+        import os
+
+x = 1; \
+import os

resources/test/fixtures/pycodestyle/E40.py

@@ -0,0 +1,61 @@
+#: E401
+import os, sys
+#: Okay
+import os
+import sys
+
+from subprocess import Popen, PIPE
+
+from myclass import MyClass
+from foo.bar.yourclass import YourClass
+
+import myclass
+import foo.bar.yourclass
+#: Okay
+__all__ = ['abc']
+
+import foo
+#: Okay
+__version__ = "42"
+
+import foo
+#: Okay
+__author__ = "Simon Gomizelj"
+
+import foo
+#: Okay
+try:
+    import foo
+except ImportError:
+    pass
+else:
+    print('imported foo')
+finally:
+    print('made attempt to import foo')
+
+import bar
+#: Okay
+with warnings.catch_warnings():
+    warnings.filterwarnings("ignore", DeprecationWarning)
+    import foo
+
+import bar
+#: Okay
+if False:
+    import foo
+elif not True:
+    import bar
+else:
+    import mwahaha
+
+import bar
+#: E402
+VERSION = '1.2.3'
+
+import foo
+#: E402
+import foo
+
+a = 1
+
+import bar

resources/test/fixtures/pycodestyle/E501.py

@@ -55,3 +55,8 @@ sit amet  consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labor
 
 # OK
 # https://loooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong.url.com
+
+# Not OK
+_ = """
+Source: https://github.com/PyCQA/pycodestyle/pull/258/files#diff-841c622497a8033d10152bfdfb15b20b92437ecdea21a260944ea86b77b51533
+"""

resources/test/fixtures/pycodestyle/E721.py

@@ -15,7 +15,7 @@ import types
 if type(res) is not types.ListType:
     pass
 #: E721
-assert type(res) == type(False) or type(res) == type(None)
+assert type(res) == type(False)
 #: E721
 assert type(res) == type([])
 #: E721
@@ -52,3 +52,5 @@ if isinstance(res, types.MethodType):
     pass
 if type(a) != type(b) or type(a) == type(ccc):
     pass
+
+assert type(res) == type(None)

resources/test/fixtures/pycodestyle/W292_2.py

@@ -1,2 +1,2 @@
 def fn() -> None:
-    pass
+    print("Newline present (no W292)")

resources/test/fixtures/pycodestyle/W292_4.py

@@ -0,0 +1 @@
+ 

resources/test/fixtures/pycodestyle/constant_literals.py

@@ -0,0 +1,39 @@
+###
+# Errors
+###
+if "abc" is "def":  # F632 (fix)
+    pass
+if "abc" is None:  # F632 (fix, but leaves behind unfixable E711)
+    pass
+if None is "abc":  # F632 (fix, but leaves behind unfixable E711)
+    pass
+if "abc" is False:  # F632 (fix, but leaves behind unfixable E712)
+    pass
+if False is "abc":  # F632 (fix, but leaves behind unfixable E712)
+    pass
+if False == None:  # E711, E712 (fix)
+    pass
+if None == False:  # E711, E712 (fix)
+    pass
+
+###
+# Unfixable errors
+###
+if "abc" == None:  # E711
+    pass
+if None == "abc":  # E711
+    pass
+if "abc" == False:  # E712
+    pass
+if False == "abc":  # E712
+    pass
+
+###
+# Non-errors
+###
+if "def" == "abc":
+    pass
+if False is None:
+    pass
+if None is False:
+    pass

resources/test/fixtures/pyflakes/F401_7.py

@@ -0,0 +1,16 @@
+"""Test: noqa directives."""
+
+from module import (
+    A,  # noqa: F401
+    B,
+)
+
+from module import (
+    A,  # noqa: F401
+    B,  # noqa: F401
+)
+
+from module import (
+    A,
+    B,
+)

resources/test/fixtures/pyflakes/F811_20.py

@@ -7,7 +7,6 @@ import fu
 
 
 class bar:
-    # STOPSHIP: This errors.
     fu = 1
 
 

resources/test/fixtures/pyflakes/F821_7.py

@@ -0,0 +1,13 @@
+"""Test: Mypy extensions."""
+
+from mypy_extensions import DefaultNamedArg
+
+# OK
+_ = DefaultNamedArg(bool | None, name="some_prop_name")
+_ = DefaultNamedArg(type=bool | None, name="some_prop_name")
+_ = DefaultNamedArg(bool | None, "some_prop_name")
+
+# Not OK
+_ = DefaultNamedArg("Undefined", name="some_prop_name")
+_ = DefaultNamedArg(type="Undefined", name="some_prop_name")
+_ = DefaultNamedArg("Undefined", "some_prop_name")

resources/test/fixtures/pyflakes/multi_statement_lines.py

@@ -0,0 +1,51 @@
+
+if True:
+    import foo; x = 1
+    import foo;     x = 1
+
+if True:
+    import foo; \
+x = 1
+
+if True:
+    import foo \
+        ; x = 1
+
+
+if True:
+    x = 1; import foo
+
+
+if True:
+    x = 1; \
+         import foo
+
+
+if True:
+    x = 1 \
+        ; import foo
+
+
+if True:
+    x = 1; import foo; x = 1
+    x = 1;     import foo;     x = 1
+
+if True:
+    x = 1; \
+        import foo; \
+    x = 1
+
+if True:
+    x = 1 \
+        ;import foo \
+        ;x = 1
+
+
+# Continuation, but not as the last content in the file.
+x = 1; \
+import foo
+
+# Continuation, followed by end-of-file. (Removing `import foo` would cause a syntax
+# error.)
+x = 1; \
+import foo

resources/test/fixtures/pygrep-hooks/PGH002_0.py

@@ -0,0 +1,8 @@
+import logging
+import warnings
+from warnings import warn
+
+warnings.warn("this is ok")
+warn("by itself is also ok")
+logging.warning("this is fine")
+log.warning("this is ok")

resources/test/fixtures/pygrep-hooks/PGH002_1.py

@@ -0,0 +1,15 @@
+import logging
+from logging import warn
+
+logging.warn("this is not ok")
+log.warn("this is also not ok")
+warn("not ok")
+
+
+def foo():
+    from logging import warn
+
+    def warn():
+        pass
+
+    warn("has been redefined, but we will still report it")

resources/test/fixtures/pygrep-hooks/PGH003_0.py

@@ -0,0 +1,11 @@
+x = 1  # type: ignore
+x = 1  # type ignore
+x = 1  # type:ignore
+
+x = 1
+x = 1  # type ignore  # noqa
+x = 1  # type: ignore[attr-defined]
+x = 1  # type: ignore[attr-defined, name-defined]
+x = 1  # type: ignore[type-mismatch]  # noqa
+x = 1  # type: Union[int, str]
+x = 1  # type: ignoreme

resources/test/fixtures/pylint/used_prior_global_declaration.py

@@ -109,6 +109,11 @@ def f():
     del x
 
 
+def f():
+    print(f"{x=}")
+    global x
+
+
 ###
 # Non-errors.
 ###
@@ -146,3 +151,8 @@ def f():
     global x, y
 
     del x
+
+
+def f():
+    global x
+    print(f"{x=}")

resources/test/fixtures/pyproject.toml

@@ -42,6 +42,9 @@ staticmethod-decorators = ["staticmethod"]
 [tool.ruff.flake8-tidy-imports]
 ban-relative-imports = "parents"
 
+[tool.ruff.flake8-errmsg]
+max-string-length = 20
+
 [tool.ruff.flake8-import-conventions.aliases]
 pandas = "pd"
 

resources/test/fixtures/pyupgrade/UP016.py

@@ -0,0 +1,87 @@
+# Replace names by built-in names, whether namespaced or not
+# https://github.com/search?q=%22from+six+import%22&type=code
+import six
+from six.moves import map  # No need
+from six import text_type
+
+six.text_type  # str
+six.binary_type  # bytes
+six.class_types  # (type,)
+six.string_types  # (str,)
+six.integer_types  # (int,)
+six.unichr  # chr
+six.iterbytes  # iter
+six.print_(...)  # print(...)
+six.exec_(c, g, l)  # exec(c, g, l)
+six.advance_iterator(it)  # next(it)
+six.next(it)  # next(it)
+six.callable(x)  # callable(x)
+six.moves.range(x)  # range(x)
+six.moves.xrange(x)  # range(x)
+isinstance(..., six.class_types)  # isinstance(..., type)
+issubclass(..., six.integer_types)  # issubclass(..., int)
+isinstance(..., six.string_types)  # isinstance(..., str)
+
+# Replace call on arg by method call on arg
+six.iteritems(dct)  # dct.items()
+six.iterkeys(dct)  # dct.keys()
+six.itervalues(dct)  # dct.values()
+six.viewitems(dct)  # dct.items()
+six.viewkeys(dct)  # dct.keys()
+six.viewvalues(dct)  # dct.values()
+six.assertCountEqual(self, a1, a2)  # self.assertCountEqual(a1, a2)
+six.assertRaisesRegex(self, e, r, fn)  # self.assertRaisesRegex(e, r, fn)
+six.assertRegex(self, s, r)  # self.assertRegex(s, r)
+
+# Replace call on arg by arg attribute
+six.get_method_function(meth)  # meth.__func__
+six.get_method_self(meth)  # meth.__self__
+six.get_function_closure(fn)  # fn.__closure__
+six.get_function_code(fn)  # fn.__code__
+six.get_function_defaults(fn)  # fn.__defaults__
+six.get_function_globals(fn)  # fn.__globals__
+
+# Replace by string literal
+six.b("...")  # b'...'
+six.u("...")  # '...'
+six.ensure_binary("...")  # b'...'
+six.ensure_str("...")  # '...'
+six.ensure_text("...")  # '...'
+six.b(string)  # no change
+
+# Replace by simple expression
+six.get_unbound_function(meth)  # meth
+six.create_unbound_method(fn, cls)  # fn
+
+# Raise exception
+six.raise_from(exc, exc_from)  # raise exc from exc_from
+six.reraise(tp, exc, tb)  # raise exc.with_traceback(tb)
+six.reraise(*sys.exc_info())  # raise
+
+# Int / Bytes conversion
+six.byte2int(bs)  # bs[0]
+six.indexbytes(bs, i)  # bs[i]
+six.int2byte(i)  # bytes((i, ))
+
+# Special cases for next calls
+next(six.iteritems(dct))  # next(iter(dct.items()))
+next(six.iterkeys(dct))  # next(iter(dct.keys()))
+next(six.itervalues(dct))  # next(iter(dct.values()))
+
+# TODO: To implement
+
+
+# Rewrite classes
+@six.python_2_unicode_compatible  # Remove
+class C(six.Iterator):
+    pass  # class C: pass
+
+
+class C(six.with_metaclass(M, B)):
+    pass  # class C(B, metaclass=M): pass
+
+
+# class C(B, metaclass=M): pass
+@six.add_metaclass(M)
+class C(B):
+    pass

resources/test/fixtures/pyupgrade/UP017.py

@@ -0,0 +1,11 @@
+import datetime
+import datetime as dt
+from datetime import timezone
+from datetime import timezone as tz
+
+print(datetime.timezone(-1))
+print(timezone.utc)
+print(tz.utc)
+
+print(datetime.timezone.utc)
+print(dt.timezone.utc)

resources/test/fixtures/pyupgrade/UP018.py

@@ -0,0 +1,25 @@
+# These remain unchanged
+str(1)
+str(*a)
+str("foo", *a)
+str(**k)
+str("foo", **k)
+str("foo", encoding="UTF-8")
+str("foo"
+    "bar")
+bytes("foo", encoding="UTF-8")
+bytes(*a)
+bytes("foo", *a)
+bytes("foo", **a)
+bytes(b"foo"
+      b"bar")
+
+# These become string or byte literals
+str()
+str("foo")
+str("""
+foo""")
+bytes()
+bytes(b"foo")
+bytes(b"""
+foo""")

resources/test/fixtures/ruff/RUF100.py

@@ -15,8 +15,8 @@ def f() -> None:
     # Invalid
     d = 1  # noqa: F841, E501
 
-    # Invalid (and unimplemented)
-    d = 1  # noqa: F841, W191
+    # Invalid (and unimplemented or not enabled)
+    d = 1  # noqa: F841, W191, F821
 
     # Invalid (but external)
     d = 1  # noqa: F841, V101
@@ -69,3 +69,20 @@ _ = """Lorem ipsum dolor sit amet.
 
 Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor.
 """  # noqa
+
+# Valid
+# this is a veryyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy long comment  # noqa: E501
+
+# Valid
+_ = """Here's a source: https://github.com/ethereum/web3.py/blob/ffe59daf10edc19ee5f05227b25bac8d090e8aa4/web3/_utils/events.py#L201
+
+May raise:
+- DeserializationError if the abi string is invalid or abi or log topics/data do not match
+"""  # noqa: E501
+
+import collections  # noqa
+import os  # noqa: F401, RUF100
+import shelve  # noqa: RUF100
+import sys  # noqa: F401, RUF100
+
+print(sys.path)

resources/test/package/pyproject.toml

@@ -0,0 +1,2 @@
+[tool.ruff]
+src = ["."]

resources/test/package/src/package/app.py

@@ -0,0 +1,4 @@
+from package.core import method
+
+if __name__ == "__main__":
+    method()

resources/test/project/README.md

@@ -9,14 +9,14 @@ Running from the repo root should pick up and enforce the appropriate settings f
 
 ```
 ∴ cargo run resources/test/project/
-Found 7 error(s).
 resources/test/project/examples/.dotfiles/script.py:1:1: I001 Import block is un-sorted or un-formatted
 resources/test/project/examples/.dotfiles/script.py:1:8: F401 `numpy` imported but unused
 resources/test/project/examples/.dotfiles/script.py:2:17: F401 `app.app_file` imported but unused
 resources/test/project/examples/docs/docs/file.py:1:1: I001 Import block is un-sorted or un-formatted
 resources/test/project/examples/docs/docs/file.py:8:5: F841 Local variable `x` is assigned to but never used
-resources/test/project/src/file.py:1:8: F401 `os` imported but unused
-resources/test/project/src/import_file.py:1:1: I001 Import block is un-sorted or un-formatted
+resources/test/project/project/file.py:1:8: F401 `os` imported but unused
+resources/test/project/project/import_file.py:1:1: I001 Import block is un-sorted or un-formatted
+Found 7 error(s).
 6 potentially fixable with the --fix option.
 ```
 
@@ -24,14 +24,14 @@ Running from the project directory itself should exhibit the same behavior:
 
 ```
 ∴ (cd resources/test/project/ && cargo run .)
-Found 7 error(s).
 examples/.dotfiles/script.py:1:1: I001 Import block is un-sorted or un-formatted
 examples/.dotfiles/script.py:1:8: F401 `numpy` imported but unused
 examples/.dotfiles/script.py:2:17: F401 `app.app_file` imported but unused
 examples/docs/docs/file.py:1:1: I001 Import block is un-sorted or un-formatted
 examples/docs/docs/file.py:8:5: F841 Local variable `x` is assigned to but never used
-src/file.py:1:8: F401 `os` imported but unused
-src/import_file.py:1:1: I001 Import block is un-sorted or un-formatted
+project/file.py:1:8: F401 `os` imported but unused
+project/import_file.py:1:1: I001 Import block is un-sorted or un-formatted
+Found 7 error(s).
 6 potentially fixable with the --fix option.
 ```
 
@@ -40,9 +40,9 @@ files:
 
 ```
 ∴ (cd resources/test/project/examples/docs && cargo run .)
-Found 2 error(s).
 docs/file.py:1:1: I001 Import block is un-sorted or un-formatted
 docs/file.py:8:5: F841 Local variable `x` is assigned to but never used
+Found 2 error(s).
 1 potentially fixable with the --fix option.
 ```
 
@@ -51,8 +51,6 @@ file paths from the current working directory:
 
 ```
 ∴ (cargo run -- --config=resources/test/project/pyproject.toml resources/test/project/)
-Found 11 error(s).
-resources/test/project/examples/.dotfiles/script.py:1:1: I001 Import block is un-sorted or un-formatted
 resources/test/project/examples/.dotfiles/script.py:1:8: F401 `numpy` imported but unused
 resources/test/project/examples/.dotfiles/script.py:2:17: F401 `app.app_file` imported but unused
 resources/test/project/examples/docs/docs/concepts/file.py:1:8: F401 `os` imported but unused
@@ -61,9 +59,9 @@ resources/test/project/examples/docs/docs/file.py:1:8: F401 `os` imported but un
 resources/test/project/examples/docs/docs/file.py:3:8: F401 `numpy` imported but unused
 resources/test/project/examples/docs/docs/file.py:4:27: F401 `docs.concepts.file` imported but unused
 resources/test/project/examples/excluded/script.py:1:8: F401 `os` imported but unused
-resources/test/project/src/file.py:1:8: F401 `os` imported but unused
-resources/test/project/src/import_file.py:1:1: I001 Import block is un-sorted or un-formatted
-11 potentially fixable with the --fix option.
+resources/test/project/project/file.py:1:8: F401 `os` imported but unused
+Found 9 error(s).
+9 potentially fixable with the --fix option.
 ```
 
 Running from a parent directory should this "ignore" the `exclude` (hence, `concepts/file.py` gets
@@ -71,11 +69,11 @@ included in the output):
 
 ```
 ∴ (cd resources/test/project/examples && cargo run -- --config=docs/pyproject.toml .)
-Found 4 error(s).
 docs/docs/concepts/file.py:5:5: F841 Local variable `x` is assigned to but never used
 docs/docs/file.py:1:1: I001 Import block is un-sorted or un-formatted
 docs/docs/file.py:8:5: F841 Local variable `x` is assigned to but never used
 excluded/script.py:5:5: F841 Local variable `x` is assigned to but never used
+Found 4 error(s).
 1 potentially fixable with the --fix option.
 ```
 
@@ -83,7 +81,14 @@ Passing an excluded directory directly should report errors in the contained fil
 
 ```
 ∴ cargo run resources/test/project/examples/excluded/
-Found 1 error(s).
 resources/test/project/examples/excluded/script.py:1:8: F401 `os` imported but unused
+Found 1 error(s).
 1 potentially fixable with the --fix option.
 ```
+
+Unless we `--force-exclude`:
+
+```
+∴ cargo run resources/test/project/examples/excluded/ --force-exclude
+∴ cargo run resources/test/project/examples/excluded/script.py --force-exclude
+```

ruff_dev/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff_dev"
-version = "0.0.182"
+version = "0.0.193"
 edition = "2021"
 
 [dependencies]
@@ -11,8 +11,10 @@ itertools = { version = "0.10.5" }
 libcst = { git = "https://github.com/charliermarsh/LibCST", rev = "f2f0b7a487a8725d161fe8b3ed73a6758b21e177" }
 once_cell = { version = "1.16.0" }
 ruff = { path = ".." }
-rustpython-ast = { features = ["unparse"], git = "https://github.com/RustPython/RustPython.git", rev = "8d879a53197f9c73062f6160410bdba796a71cbf" }
-rustpython-common = { git = "https://github.com/RustPython/RustPython.git", rev = "8d879a53197f9c73062f6160410bdba796a71cbf" }
-rustpython-parser = { features = ["lalrpop"], git = "https://github.com/RustPython/RustPython.git", rev = "8d879a53197f9c73062f6160410bdba796a71cbf" }
+rustpython-ast = { features = ["unparse"], git = "https://github.com/RustPython/RustPython.git", rev = "1b6cb170e925a43d605b3fed9f6b878e63e47744" }
+rustpython-common = { git = "https://github.com/RustPython/RustPython.git", rev = "1b6cb170e925a43d605b3fed9f6b878e63e47744" }
+rustpython-parser = { features = ["lalrpop"], git = "https://github.com/RustPython/RustPython.git", rev = "1b6cb170e925a43d605b3fed9f6b878e63e47744" }
+schemars = { version = "0.8.11" }
+serde_json = {version="1.0.91"}
 strum = { version = "0.24.1", features = ["strum_macros"] }
 strum_macros = { version = "0.24.3" }

ruff_dev/src/generate_check_code_prefix.rs

@@ -1,18 +1,18 @@
 //! Generate the `CheckCodePrefix` enum.
 
 use std::collections::{BTreeMap, BTreeSet};
-use std::fs::OpenOptions;
+use std::fs;
 use std::io::Write;
+use std::path::PathBuf;
+use std::process::{Command, Output, Stdio};
 
-use anyhow::Result;
+use anyhow::{ensure, Result};
 use clap::Parser;
 use codegen::{Scope, Type, Variant};
 use itertools::Itertools;
-use ruff::checks::{CheckCode, CODE_REDIRECTS, PREFIX_REDIRECTS};
+use ruff::checks::{CheckCode, PREFIX_REDIRECTS};
 use strum::IntoEnumIterator;
 
-const FILE: &str = "src/checks_gen.rs";
-
 #[derive(Parser)]
 #[command(author, version, about, long_about = None)]
 pub struct Cli {
@@ -40,18 +40,7 @@ pub fn main(cli: &Cli) -> Result<()> {
     }
 
     // Add any prefix aliases (e.g., "U" to "UP").
-    for (alias, source) in PREFIX_REDIRECTS.iter() {
-        prefix_to_codes.insert(
-            (*alias).to_string(),
-            prefix_to_codes
-                .get(&(*source).to_string())
-                .unwrap_or_else(|| panic!("Unknown CheckCode: {source:?}"))
-                .clone(),
-        );
-    }
-
-    // Add any check code aliases (e.g., "U001" to "UP001").
-    for (alias, check_code) in CODE_REDIRECTS.iter() {
+    for (alias, check_code) in PREFIX_REDIRECTS.iter() {
         prefix_to_codes.insert(
             (*alias).to_string(),
             prefix_to_codes
@@ -76,7 +65,8 @@ pub fn main(cli: &Cli) -> Result<()> {
         .derive("Ord")
         .derive("Clone")
         .derive("Serialize")
-        .derive("Deserialize");
+        .derive("Deserialize")
+        .derive("JsonSchema");
     for prefix in prefix_to_codes.keys() {
         gen = gen.push_variant(Variant::new(prefix.to_string()));
     }
@@ -105,9 +95,9 @@ pub fn main(cli: &Cli) -> Result<()> {
         .line("#[allow(clippy::match_same_arms)]")
         .line("match self {");
     for (prefix, codes) in &prefix_to_codes {
-        if let Some(target) = CODE_REDIRECTS.get(&prefix.as_str()) {
+        if let Some(target) = PREFIX_REDIRECTS.get(&prefix.as_str()) {
             gen = gen.line(format!(
-                "CheckCodePrefix::{prefix} => {{ eprintln!(\"{{}}{{}} {{}}\", \
+                "CheckCodePrefix::{prefix} => {{ one_time_warning!(\"{{}}{{}} {{}}\", \
                  \"warning\".yellow().bold(), \":\".bold(), \"`{}` has been remapped to \
                  `{}`\".bold()); \n vec![{}] }}",
                 prefix,
@@ -117,18 +107,6 @@ pub fn main(cli: &Cli) -> Result<()> {
                     .map(|code| format!("CheckCode::{}", code.as_ref()))
                     .join(", ")
             ));
-        } else if let Some(target) = PREFIX_REDIRECTS.get(&prefix.as_str()) {
-            gen = gen.line(format!(
-                "CheckCodePrefix::{prefix} => {{ eprintln!(\"{{}}{{}} {{}}\", \
-                 \"warning\".yellow().bold(), \":\".bold(), \"`{}` has been remapped to \
-                 `{}`\".bold()); \n vec![{}] }}",
-                prefix,
-                target,
-                codes
-                    .iter()
-                    .map(|code| format!("CheckCode::{}", code.as_ref()))
-                    .join(", ")
-            ));
         } else {
             gen = gen.line(format!(
                 "CheckCodePrefix::{prefix} => vec![{}],",
@@ -161,8 +139,7 @@ pub fn main(cli: &Cli) -> Result<()> {
             _ => panic!("Invalid prefix: {prefix}"),
         };
         gen = gen.line(format!(
-            "CheckCodePrefix::{prefix} => SuffixLength::{},",
-            specificity
+            "CheckCodePrefix::{prefix} => SuffixLength::{specificity},"
         ));
     }
     gen.line("}");
@@ -175,6 +152,8 @@ pub fn main(cli: &Cli) -> Result<()> {
     output.push('\n');
     output.push_str("use colored::Colorize;");
     output.push('\n');
+    output.push_str("use schemars::JsonSchema;");
+    output.push('\n');
     output.push_str("use serde::{Deserialize, Serialize};");
     output.push('\n');
     output.push_str("use strum_macros::{AsRefStr, EnumString};");
@@ -182,6 +161,8 @@ pub fn main(cli: &Cli) -> Result<()> {
     output.push('\n');
     output.push_str("use crate::checks::CheckCode;");
     output.push('\n');
+    output.push_str("use crate::one_time_warning;");
+    output.push('\n');
     output.push('\n');
     output.push_str(&scope.to_string());
     output.push('\n');
@@ -202,12 +183,25 @@ pub fn main(cli: &Cli) -> Result<()> {
     output.push('\n');
     output.push('\n');
 
+    let rustfmt = Command::new("rustfmt")
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .spawn()?;
+    write!(rustfmt.stdin.as_ref().unwrap(), "{output}")?;
+    let Output { status, stdout, .. } = rustfmt.wait_with_output()?;
+    ensure!(status.success(), "rustfmt failed with {status}");
+
     // Write the output to `src/checks_gen.rs` (or stdout).
     if cli.dry_run {
-        println!("{output}");
+        println!("{}", String::from_utf8(stdout)?);
     } else {
-        let mut f = OpenOptions::new().write(true).truncate(true).open(FILE)?;
-        write!(f, "{output}")?;
+        let file = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+            .parent()
+            .expect("Failed to find root directory")
+            .join("src/checks_gen.rs");
+        if fs::read(&file).map_or(true, |old| old != stdout) {
+            fs::write(&file, stdout)?;
+        }
     }
 
     Ok(())

ruff_dev/src/generate_json_schema.rs

@@ -0,0 +1,30 @@
+use std::fs;
+use std::path::PathBuf;
+
+use anyhow::Result;
+use clap::Args;
+use ruff::settings::options::Options;
+use schemars::schema_for;
+
+#[derive(Args)]
+pub struct Cli {
+    /// Write the generated table to stdout (rather than to `ruff.schema.json`).
+    #[arg(long)]
+    dry_run: bool,
+}
+
+pub fn main(cli: &Cli) -> Result<()> {
+    let schema = schema_for!(Options);
+    let schema_string = serde_json::to_string_pretty(&schema).unwrap();
+
+    if cli.dry_run {
+        println!("{schema_string}");
+    } else {
+        let file = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+            .parent()
+            .expect("Failed to find root directory")
+            .join("ruff.schema.json");
+        fs::write(file, schema_string.as_bytes())?;
+    }
+    Ok(())
+}

ruff_dev/src/lib.rs

@@ -12,6 +12,7 @@
 )]
 
 pub mod generate_check_code_prefix;
+pub mod generate_json_schema;
 pub mod generate_options;
 pub mod generate_rules_table;
 pub mod generate_source_code;

ruff_dev/src/main.rs

@@ -14,8 +14,8 @@
 use anyhow::Result;
 use clap::{Parser, Subcommand};
 use ruff_dev::{
-    generate_check_code_prefix, generate_options, generate_rules_table, generate_source_code,
-    print_ast, print_cst, print_tokens,
+    generate_check_code_prefix, generate_json_schema, generate_options, generate_rules_table,
+    generate_source_code, print_ast, print_cst, print_tokens,
 };
 
 #[derive(Parser)]
@@ -30,6 +30,8 @@ struct Cli {
 enum Commands {
     /// Generate the `CheckCodePrefix` enum.
     GenerateCheckCodePrefix(generate_check_code_prefix::Cli),
+    /// Generate JSON schema for the TOML configuration file.
+    GenerateJSONSchema(generate_json_schema::Cli),
     /// Generate a Markdown-compatible table of supported lint rules.
     GenerateRulesTable(generate_rules_table::Cli),
     /// Generate a Markdown-compatible listing of configuration options.
@@ -48,6 +50,7 @@ fn main() -> Result<()> {
     let cli = Cli::parse();
     match &cli.command {
         Commands::GenerateCheckCodePrefix(args) => generate_check_code_prefix::main(args)?,
+        Commands::GenerateJSONSchema(args) => generate_json_schema::main(args)?,
         Commands::GenerateRulesTable(args) => generate_rules_table::main(args)?,
         Commands::GenerateSourceCode(args) => generate_source_code::main(args)?,
         Commands::GenerateOptions(args) => generate_options::main(args)?,

ruff_macros/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff_macros"
-version = "0.0.182"
+version = "0.0.193"
 edition = "2021"
 
 [lib]

ruff_macros/src/lib.rs

@@ -13,13 +13,14 @@
 
 use quote::{quote, quote_spanned};
 use syn::parse::{Parse, ParseStream};
+use syn::spanned::Spanned;
 use syn::token::Comma;
 use syn::{
     parse_macro_input, AngleBracketedGenericArguments, Attribute, Data, DataStruct, DeriveInput,
     Field, Fields, Lit, LitStr, Path, PathArguments, PathSegment, Token, Type, TypePath,
 };
 
-#[proc_macro_derive(ConfigurationOptions, attributes(option, option_group))]
+#[proc_macro_derive(ConfigurationOptions, attributes(option, doc, option_group))]
 pub fn derive(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
     let input = parse_macro_input!(input as DeriveInput);
 
@@ -39,11 +40,28 @@ fn derive_impl(input: DeriveInput) -> syn::Result<proc_macro2::TokenStream> {
             let mut output = vec![];
 
             for field in fields.named.iter() {
-                if let Some(attr) = field.attrs.iter().find(|a| a.path.is_ident("option")) {
-                    output.push(handle_option(field, attr)?);
+                let docs: Vec<&Attribute> = field
+                    .attrs
+                    .iter()
+                    .filter(|attr| attr.path.is_ident("doc"))
+                    .collect();
+
+                if docs.is_empty() {
+                    return Err(syn::Error::new(
+                        field.span(),
+                        "Missing documentation for field",
+                    ));
+                }
+
+                if let Some(attr) = field.attrs.iter().find(|attr| attr.path.is_ident("option")) {
+                    output.push(handle_option(field, attr, docs)?);
                 };
 
-                if field.attrs.iter().any(|a| a.path.is_ident("option_group")) {
+                if field
+                    .attrs
+                    .iter()
+                    .any(|attr| attr.path.is_ident("option_group"))
+                {
                     output.push(handle_option_group(field)?);
                 };
             }
@@ -70,8 +88,10 @@ fn derive_impl(input: DeriveInput) -> syn::Result<proc_macro2::TokenStream> {
 /// deriving `ConfigurationOptions`, create code that calls retrieves options
 /// from that group: `Foobar::get_available_options()`
 fn handle_option_group(field: &Field) -> syn::Result<proc_macro2::TokenStream> {
-    // unwrap is safe because we're only going over named fields
-    let ident = field.ident.as_ref().unwrap();
+    let ident = field
+        .ident
+        .as_ref()
+        .expect("Expected to handle named fields");
 
     match &field.ty {
         Type::Path(TypePath {
@@ -103,17 +123,49 @@ fn handle_option_group(field: &Field) -> syn::Result<proc_macro2::TokenStream> {
     }
 }
 
+/// Parse a `doc` attribute into it a string literal.
+fn parse_doc(doc: &Attribute) -> syn::Result<String> {
+    let doc = doc
+        .parse_meta()
+        .map_err(|e| syn::Error::new(doc.span(), e))?;
+
+    match doc {
+        syn::Meta::NameValue(syn::MetaNameValue {
+            lit: Lit::Str(lit_str),
+            ..
+        }) => Ok(lit_str.value()),
+        _ => Err(syn::Error::new(doc.span(), "Expected doc attribute.")),
+    }
+}
+
 /// Parse an `#[option(doc="...", default="...", value_type="...",
 /// example="...")]` attribute and return data in the form of an `OptionField`.
-fn handle_option(field: &Field, attr: &Attribute) -> syn::Result<proc_macro2::TokenStream> {
-    // unwrap is safe because we're only going over named fields
-    let ident = field.ident.as_ref().unwrap();
+fn handle_option(
+    field: &Field,
+    attr: &Attribute,
+    docs: Vec<&Attribute>,
+) -> syn::Result<proc_macro2::TokenStream> {
+    // Convert the list of `doc` attributes into a single string.
+    let doc = textwrap::dedent(
+        &docs
+            .into_iter()
+            .map(parse_doc)
+            .collect::<syn::Result<Vec<_>>>()?
+            .join("\n"),
+    )
+    .trim_matches('\n')
+    .to_string();
+
+    let ident = field
+        .ident
+        .as_ref()
+        .expect("Expected to handle named fields");
 
     let FieldAttributes {
-        doc,
         default,
         value_type,
         example,
+        ..
     } = attr.parse_args::<FieldAttributes>()?;
     let kebab_name = LitStr::new(&ident.to_string().replace('_', "-"), ident.span());
 
@@ -130,7 +182,6 @@ fn handle_option(field: &Field, attr: &Attribute) -> syn::Result<proc_macro2::To
 
 #[derive(Debug)]
 struct FieldAttributes {
-    doc: String,
     default: String,
     value_type: String,
     example: String,
@@ -138,8 +189,6 @@ struct FieldAttributes {
 
 impl Parse for FieldAttributes {
     fn parse(input: ParseStream) -> syn::Result<Self> {
-        let doc = _parse_key_value(input, "doc")?;
-        input.parse::<Comma>()?;
         let default = _parse_key_value(input, "default")?;
         input.parse::<Comma>()?;
         let value_type = _parse_key_value(input, "value_type")?;
@@ -150,7 +199,6 @@ impl Parse for FieldAttributes {
         }
 
         Ok(FieldAttributes {
-            doc: textwrap::dedent(&doc).trim_matches('\n').to_string(),
             default,
             value_type,
             example: textwrap::dedent(&example).trim_matches('\n').to_string(),

src/ast/helpers.rs

@@ -3,7 +3,8 @@ use once_cell::sync::Lazy;
 use regex::Regex;
 use rustc_hash::{FxHashMap, FxHashSet};
 use rustpython_ast::{
-    Arguments, Excepthandler, ExcepthandlerKind, Expr, ExprKind, Location, Stmt, StmtKind,
+    Arguments, Constant, Excepthandler, ExcepthandlerKind, Expr, ExprKind, Keyword, KeywordData,
+    Location, Stmt, StmtKind,
 };
 use rustpython_parser::lexer;
 use rustpython_parser::lexer::Tok;
@@ -11,6 +12,16 @@ use rustpython_parser::lexer::Tok;
 use crate::ast::types::Range;
 use crate::SourceCodeLocator;
 
+/// Create an `Expr` with default location from an `ExprKind`.
+pub fn create_expr(node: ExprKind) -> Expr {
+    Expr::new(Location::default(), Location::default(), node)
+}
+
+/// Create a `Stmt` with a default location from a `StmtKind`.
+pub fn create_stmt(node: StmtKind) -> Stmt {
+    Stmt::new(Location::default(), Location::default(), node)
+}
+
 fn collect_call_path_inner<'a>(expr: &'a Expr, parts: &mut Vec<&'a str>) {
     match &expr.node {
         ExprKind::Call { func, .. } => {
@@ -152,15 +163,12 @@ pub fn match_call_path(
 
 static DUNDER_REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"__[^\s]+__").unwrap());
 
-pub fn is_assignment_to_a_dunder(node: &StmtKind) -> bool {
+/// Return `true` if the `Stmt` is an assignment to a dunder (like `__all__`).
+pub fn is_assignment_to_a_dunder(stmt: &Stmt) -> bool {
     // Check whether it's an assignment to a dunder, with or without a type
     // annotation. This is what pycodestyle (as of 2.9.1) does.
-    match node {
-        StmtKind::Assign {
-            targets,
-            value: _,
-            type_comment: _,
-        } => {
+    match &stmt.node {
+        StmtKind::Assign { targets, .. } => {
             if targets.len() != 1 {
                 return false;
             }
@@ -169,12 +177,7 @@ pub fn is_assignment_to_a_dunder(node: &StmtKind) -> bool {
                 _ => false,
             }
         }
-        StmtKind::AnnAssign {
-            target,
-            annotation: _,
-            value: _,
-            simple: _,
-        } => match &target.node {
+        StmtKind::AnnAssign { target, .. } => match &target.node {
             ExprKind::Name { id, ctx: _ } => DUNDER_REGEX.is_match(id),
             _ => false,
         },
@@ -182,6 +185,60 @@ pub fn is_assignment_to_a_dunder(node: &StmtKind) -> bool {
     }
 }
 
+/// Return `true` if the `Expr` is a singleton (`None`, `True`, `False`, or
+/// `...`).
+pub fn is_singleton(expr: &Expr) -> bool {
+    matches!(
+        expr.node,
+        ExprKind::Constant {
+            value: Constant::None | Constant::Bool(_) | Constant::Ellipsis,
+            ..
+        }
+    )
+}
+
+/// Return `true` if the `Expr` is a constant or tuple of constants.
+pub fn is_constant(expr: &Expr) -> bool {
+    match &expr.node {
+        ExprKind::Constant { .. } => true,
+        ExprKind::Tuple { elts, .. } => elts.iter().all(is_constant),
+        _ => false,
+    }
+}
+
+/// Return `true` if the `Expr` is a non-singleton constant.
+pub fn is_constant_non_singleton(expr: &Expr) -> bool {
+    is_constant(expr) && !is_singleton(expr)
+}
+
+/// Return the `Keyword` with the given name, if it's present in the list of
+/// `Keyword` arguments.
+pub fn find_keyword<'a>(keywords: &'a [Keyword], keyword_name: &str) -> Option<&'a Keyword> {
+    keywords.iter().find(|keyword| {
+        let KeywordData { arg, .. } = &keyword.node;
+        arg.as_ref().map_or(false, |arg| arg == keyword_name)
+    })
+}
+
+/// Return `true` if an `Expr` is `None`.
+pub fn is_const_none(expr: &Expr) -> bool {
+    matches!(
+        &expr.node,
+        ExprKind::Constant {
+            value: Constant::None,
+            kind: None
+        },
+    )
+}
+
+/// Return `true` if a keyword argument is present with a non-`None` value.
+pub fn has_non_none_keyword(keywords: &[Keyword], keyword: &str) -> bool {
+    find_keyword(keywords, keyword).map_or(false, |keyword| {
+        let KeywordData { value, .. } = &keyword.node;
+        !is_const_none(value)
+    })
+}
+
 /// Extract the names of all handled exceptions.
 pub fn extract_handler_names(handlers: &[Excepthandler]) -> Vec<Vec<&str>> {
     let mut handler_names = vec![];
@@ -232,7 +289,6 @@ pub fn collect_arg_names<'a>(arguments: &'a Arguments) -> FxHashSet<&'a str> {
 
 /// Returns `true` if a call is an argumented `super` invocation.
 pub fn is_super_call_with_arguments(func: &Expr, args: &[Expr]) -> bool {
-    // Check: is this a `super` call?
     if let ExprKind::Name { id, .. } = &func.node {
         id == "super" && !args.is_empty()
     } else {
@@ -340,6 +396,39 @@ pub fn identifier_range(stmt: &Stmt, locator: &SourceCodeLocator) -> Range {
     Range::from_located(stmt)
 }
 
+/// Return `true` if a `Stmt` appears to be part of a multi-statement line, with
+/// other statements preceding it.
+pub fn preceded_by_continuation(stmt: &Stmt, locator: &SourceCodeLocator) -> bool {
+    // Does the previous line end in a continuation? This will have a specific
+    // false-positive, which is that if the previous line ends in a comment, it
+    // will be treated as a continuation. So we should only use this information to
+    // make conservative choices.
+    // TODO(charlie): Come up with a more robust strategy.
+    if stmt.location.row() > 1 {
+        let range = Range {
+            location: Location::new(stmt.location.row() - 1, 0),
+            end_location: Location::new(stmt.location.row(), 0),
+        };
+        let line = locator.slice_source_code_range(&range);
+        if line.trim().ends_with('\\') {
+            return true;
+        }
+    }
+    false
+}
+
+/// Return `true` if a `Stmt` appears to be part of a multi-statement line, with
+/// other statements preceding it.
+pub fn preceded_by_multi_statement_line(stmt: &Stmt, locator: &SourceCodeLocator) -> bool {
+    match_leading_content(stmt, locator) || preceded_by_continuation(stmt, locator)
+}
+
+/// Return `true` if a `Stmt` appears to be part of a multi-statement line, with
+/// other statements following it.
+pub fn followed_by_multi_statement_line(stmt: &Stmt, locator: &SourceCodeLocator) -> bool {
+    match_trailing_content(stmt, locator)
+}
+
 #[cfg(test)]
 mod tests {
     use anyhow::Result;
@@ -347,7 +436,7 @@ mod tests {
     use rustpython_ast::Location;
     use rustpython_parser::parser;
 
-    use crate::ast::helpers::{identifier_range, match_module_member};
+    use crate::ast::helpers::{identifier_range, match_module_member, match_trailing_content};
     use crate::ast::types::Range;
     use crate::source_code_locator::SourceCodeLocator;
 
@@ -494,6 +583,45 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn trailing_content() -> Result<()> {
+        let contents = "x = 1";
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert!(!match_trailing_content(stmt, &locator));
+
+        let contents = "x = 1; y = 2";
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert!(match_trailing_content(stmt, &locator));
+
+        let contents = "x = 1  ";
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert!(!match_trailing_content(stmt, &locator));
+
+        let contents = "x = 1  # Comment";
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert!(!match_trailing_content(stmt, &locator));
+
+        let contents = r#"
+x = 1
+y = 2
+"#
+        .trim();
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert!(!match_trailing_content(stmt, &locator));
+
+        Ok(())
+    }
+
     #[test]
     fn extract_identifier_range() -> Result<()> {
         let contents = "def f(): pass".trim();

src/ast/whitespace.rs

@@ -4,7 +4,7 @@ use std::str::Lines;
 use rustpython_ast::{Located, Location};
 
 use crate::ast::types::Range;
-use crate::check_ast::Checker;
+use crate::checkers::ast::Checker;
 
 /// Extract the leading indentation from a line.
 pub fn indentation<'a, T>(checker: &'a Checker, located: &'a Located<T>) -> Cow<'a, str> {

src/autofix/fixer.rs

@@ -10,7 +10,7 @@ use crate::autofix::Fix;
 use crate::checks::Check;
 use crate::source_code_locator::SourceCodeLocator;
 
-#[derive(Debug, Hash)]
+#[derive(Debug, Copy, Clone, Hash)]
 pub enum Mode {
     Generate,
     Apply,
@@ -27,15 +27,6 @@ impl From<bool> for Mode {
     }
 }
 
-impl From<&Mode> for bool {
-    fn from(value: &Mode) -> Self {
-        match value {
-            Mode::Generate | Mode::Apply => true,
-            Mode::None => false,
-        }
-    }
-}
-
 /// Auto-fix errors in a file, and write the fixed source code to disk.
 pub fn fix_file<'a>(
     checks: &'a [Check],

src/autofix/helpers.rs

@@ -2,7 +2,11 @@ use anyhow::{bail, Result};
 use itertools::Itertools;
 use rustpython_parser::ast::{ExcepthandlerKind, Location, Stmt, StmtKind};
 
+use crate::ast::helpers;
+use crate::ast::helpers::to_absolute;
+use crate::ast::whitespace::LinesWithTrailingNewline;
 use crate::autofix::Fix;
+use crate::source_code_locator::SourceCodeLocator;
 
 /// Determine if a body contains only a single statement, taking into account
 /// deleted.
@@ -66,7 +70,87 @@ fn is_lone_child(child: &Stmt, parent: &Stmt, deleted: &[&Stmt]) -> Result<bool>
     }
 }
 
-pub fn remove_stmt(stmt: &Stmt, parent: Option<&Stmt>, deleted: &[&Stmt]) -> Result<Fix> {
+/// Return the location of a trailing semicolon following a `Stmt`, if it's part
+/// of a multi-statement line.
+fn trailing_semicolon(stmt: &Stmt, locator: &SourceCodeLocator) -> Option<Location> {
+    let contents = locator.slice_source_code_at(&stmt.end_location.unwrap());
+    for (row, line) in LinesWithTrailingNewline::from(&contents).enumerate() {
+        let trimmed = line.trim();
+        if trimmed.starts_with(';') {
+            let column = line
+                .char_indices()
+                .find_map(|(column, char)| if char == ';' { Some(column) } else { None })
+                .unwrap();
+            return Some(to_absolute(
+                Location::new(row + 1, column),
+                stmt.end_location.unwrap(),
+            ));
+        }
+        if !trimmed.starts_with('\\') {
+            break;
+        }
+    }
+    None
+}
+
+/// Find the next valid break for a `Stmt` after a semicolon.
+fn next_stmt_break(semicolon: Location, locator: &SourceCodeLocator) -> Location {
+    let start_location = Location::new(semicolon.row(), semicolon.column() + 1);
+    let contents = locator.slice_source_code_at(&start_location);
+    for (row, line) in LinesWithTrailingNewline::from(&contents).enumerate() {
+        let trimmed = line.trim();
+        // Skip past any continuations.
+        if trimmed.starts_with('\\') {
+            continue;
+        }
+        return if trimmed.is_empty() {
+            // If the line is empty, then despite the previous statement ending in a
+            // semicolon, we know that it's not a multi-statement line.
+            to_absolute(Location::new(row + 1, 0), start_location)
+        } else {
+            // Otherwise, find the start of the next statement. (Or, anything that isn't
+            // whitespace.)
+            let column = line
+                .char_indices()
+                .find_map(|(column, char)| {
+                    if char.is_whitespace() {
+                        None
+                    } else {
+                        Some(column)
+                    }
+                })
+                .unwrap();
+            to_absolute(Location::new(row + 1, column), start_location)
+        };
+    }
+    Location::new(start_location.row() + 1, 0)
+}
+
+/// Return `true` if a `Stmt` occurs at the end of a file.
+fn is_end_of_file(stmt: &Stmt, locator: &SourceCodeLocator) -> bool {
+    let contents = locator.slice_source_code_at(&stmt.end_location.unwrap());
+    contents.is_empty()
+}
+
+/// Return the `Fix` to use when deleting a `Stmt`.
+///
+/// In some cases, this is as simple as deleting the `Range` of the `Stmt`
+/// itself. However, there are a few exceptions:
+/// - If the `Stmt` is _not_ the terminal statement in a multi-statement line,
+///   we need to delete up to the start of the next statement (and avoid
+///   deleting any content that precedes the statement).
+/// - If the `Stmt` is the terminal statement in a multi-statement line, we need
+///   to avoid deleting any content that precedes the statement.
+/// - If the `Stmt` has no trailing and leading content, then it's convenient to
+///   remove the entire start and end lines.
+/// - If the `Stmt` is the last statement in its parent body, replace it with a
+///   `pass` instead.
+pub fn delete_stmt(
+    stmt: &Stmt,
+    parent: Option<&Stmt>,
+    deleted: &[&Stmt],
+    locator: &SourceCodeLocator,
+) -> Result<Fix> {
     if parent
         .map(|parent| is_lone_child(stmt, parent, deleted))
         .map_or(Ok(None), |v| v.map(Some))?
@@ -80,12 +164,103 @@ pub fn remove_stmt(stmt: &Stmt, parent: Option<&Stmt>, deleted: &[&Stmt]) -> Res
             stmt.end_location.unwrap(),
         ))
     } else {
-        // Otherwise, nuke the entire line.
-        // TODO(charlie): This logic assumes that there are no multi-statement physical
-        // lines.
-        Ok(Fix::deletion(
-            Location::new(stmt.location.row(), 0),
-            Location::new(stmt.end_location.unwrap().row() + 1, 0),
-        ))
+        Ok(if let Some(semicolon) = trailing_semicolon(stmt, locator) {
+            let next = next_stmt_break(semicolon, locator);
+            Fix::deletion(stmt.location, next)
+        } else if helpers::match_leading_content(stmt, locator) {
+            Fix::deletion(stmt.location, stmt.end_location.unwrap())
+        } else if helpers::preceded_by_continuation(stmt, locator) {
+            if is_end_of_file(stmt, locator) && stmt.location.column() == 0 {
+                // Special-case: a file can't end in a continuation.
+                Fix::replacement("\n".to_string(), stmt.location, stmt.end_location.unwrap())
+            } else {
+                Fix::deletion(stmt.location, stmt.end_location.unwrap())
+            }
+        } else {
+            Fix::deletion(
+                Location::new(stmt.location.row(), 0),
+                Location::new(stmt.end_location.unwrap().row() + 1, 0),
+            )
+        })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use anyhow::Result;
+    use rustpython_ast::Location;
+    use rustpython_parser::parser;
+
+    use crate::autofix::helpers::{next_stmt_break, trailing_semicolon};
+    use crate::source_code_locator::SourceCodeLocator;
+
+    #[test]
+    fn find_semicolon() -> Result<()> {
+        let contents = "x = 1";
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(trailing_semicolon(stmt, &locator), None);
+
+        let contents = "x = 1; y = 1";
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            trailing_semicolon(stmt, &locator),
+            Some(Location::new(1, 5))
+        );
+
+        let contents = "x = 1 ; y = 1";
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            trailing_semicolon(stmt, &locator),
+            Some(Location::new(1, 6))
+        );
+
+        let contents = r#"
+x = 1 \
+  ; y = 1
+"#
+        .trim();
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            trailing_semicolon(stmt, &locator),
+            Some(Location::new(2, 2))
+        );
+
+        Ok(())
+    }
+
+    #[test]
+    fn find_next_stmt_break() {
+        let contents = "x = 1; y = 1";
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            next_stmt_break(Location::new(1, 4), &locator),
+            Location::new(1, 5)
+        );
+
+        let contents = "x = 1 ; y = 1";
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            next_stmt_break(Location::new(1, 5), &locator),
+            Location::new(1, 6)
+        );
+
+        let contents = r#"
+x = 1 \
+  ; y = 1
+"#
+        .trim();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            next_stmt_break(Location::new(2, 2), &locator),
+            Location::new(2, 4)
+        );
     }
 }

src/cache.rs

@@ -3,18 +3,20 @@ use std::fs;
 use std::fs::{create_dir_all, File, Metadata};
 use std::hash::{Hash, Hasher};
 use std::io::Write;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 
 use anyhow::Result;
 use filetime::FileTime;
 use log::error;
+use once_cell::sync::Lazy;
 use path_absolutize::Absolutize;
 use serde::{Deserialize, Serialize};
 
 use crate::autofix::fixer;
 use crate::message::Message;
-use crate::settings::Settings;
+use crate::settings::{flags, Settings};
 
+static CACHE_DIR: Lazy<Option<String>> = Lazy::new(|| std::env::var("RUFF_CACHE_DIR").ok());
 const CARGO_PKG_VERSION: &str = env!("CARGO_PKG_VERSION");
 
 #[derive(Serialize, Deserialize)]
@@ -34,64 +36,29 @@ struct CheckResult {
     messages: Vec<Message>,
 }
 
-pub enum Mode {
-    ReadWrite,
-    ReadOnly,
-    WriteOnly,
-    None,
+/// Return the cache directory for a given project root. Defers to the
+/// `RUFF_CACHE_DIR` environment variable, if set.
+pub fn cache_dir(project_root: &Path) -> PathBuf {
+    CACHE_DIR
+        .as_ref()
+        .map_or_else(|| project_root.join(".ruff_cache"), PathBuf::from)
 }
 
-impl Mode {
-    fn allow_read(&self) -> bool {
-        match self {
-            Mode::ReadWrite => true,
-            Mode::ReadOnly => true,
-            Mode::WriteOnly => false,
-            Mode::None => false,
-        }
-    }
-
-    fn allow_write(&self) -> bool {
-        match self {
-            Mode::ReadWrite => true,
-            Mode::ReadOnly => false,
-            Mode::WriteOnly => true,
-            Mode::None => false,
-        }
-    }
+fn content_dir() -> &'static Path {
+    Path::new("content")
 }
 
-impl From<bool> for Mode {
-    fn from(value: bool) -> Self {
-        if value {
-            Mode::ReadWrite
-        } else {
-            Mode::None
-        }
-    }
-}
-
-fn cache_dir() -> &'static str {
-    "./.ruff_cache"
-}
-
-fn content_dir() -> &'static str {
-    "content"
-}
-
-fn cache_key(path: &Path, settings: &Settings, autofix: &fixer::Mode) -> u64 {
+fn cache_key<P: AsRef<Path>>(path: P, settings: &Settings, autofix: fixer::Mode) -> u64 {
     let mut hasher = DefaultHasher::new();
     CARGO_PKG_VERSION.hash(&mut hasher);
-    path.absolutize().unwrap().hash(&mut hasher);
+    path.as_ref().absolutize().unwrap().hash(&mut hasher);
     settings.hash(&mut hasher);
     autofix.hash(&mut hasher);
     hasher.finish()
 }
 
-/// Initialize the cache directory.
-pub fn init() -> Result<()> {
-    let path = Path::new(cache_dir());
-
+/// Initialize the cache at the specified `Path`.
+pub fn init(path: &Path) -> Result<()> {
     // Create the cache directories.
     create_dir_all(path.join(content_dir()))?;
 
@@ -110,36 +77,30 @@ pub fn init() -> Result<()> {
     Ok(())
 }
 
-fn write_sync(key: u64, value: &[u8]) -> Result<(), std::io::Error> {
+fn write_sync(cache_dir: &Path, key: u64, value: &[u8]) -> Result<(), std::io::Error> {
     fs::write(
-        Path::new(cache_dir())
-            .join(content_dir())
-            .join(format!("{key:x}")),
+        cache_dir.join(content_dir()).join(format!("{key:x}")),
         value,
     )
 }
 
-fn read_sync(key: u64) -> Result<Vec<u8>, std::io::Error> {
-    fs::read(
-        Path::new(cache_dir())
-            .join(content_dir())
-            .join(format!("{key:x}")),
-    )
+fn read_sync(cache_dir: &Path, key: u64) -> Result<Vec<u8>, std::io::Error> {
+    fs::read(cache_dir.join(content_dir()).join(format!("{key:x}")))
 }
 
 /// Get a value from the cache.
-pub fn get(
-    path: &Path,
+pub fn get<P: AsRef<Path>>(
+    path: P,
     metadata: &Metadata,
     settings: &Settings,
-    autofix: &fixer::Mode,
-    mode: &Mode,
+    autofix: fixer::Mode,
+    cache: flags::Cache,
 ) -> Option<Vec<Message>> {
-    if !mode.allow_read() {
+    if matches!(cache, flags::Cache::Disabled) {
         return None;
     };
 
-    let encoded = read_sync(cache_key(path, settings, autofix)).ok()?;
+    let encoded = read_sync(&settings.cache_dir, cache_key(path, settings, autofix)).ok()?;
     let (mtime, messages) = match bincode::deserialize::<CheckResult>(&encoded[..]) {
         Ok(CheckResult {
             metadata: CacheMetadata { mtime },
@@ -157,15 +118,15 @@ pub fn get(
 }
 
 /// Set a value in the cache.
-pub fn set(
-    path: &Path,
+pub fn set<P: AsRef<Path>>(
+    path: P,
     metadata: &Metadata,
     settings: &Settings,
-    autofix: &fixer::Mode,
+    autofix: fixer::Mode,
     messages: &[Message],
-    mode: &Mode,
+    cache: flags::Cache,
 ) {
-    if !mode.allow_write() {
+    if matches!(cache, flags::Cache::Disabled) {
         return;
     };
 
@@ -176,6 +137,7 @@ pub fn set(
         messages,
     };
     if let Err(e) = write_sync(
+        &settings.cache_dir,
         cache_key(path, settings, autofix),
         &bincode::serialize(&check_result).unwrap(),
     ) {

src/check_lines.rs

@@ -1,288 +0,0 @@
-//! Lint rules based on checking raw physical lines.
-
-use nohash_hasher::IntMap;
-use once_cell::sync::Lazy;
-use regex::Regex;
-use rustpython_parser::ast::Location;
-
-use crate::ast::types::Range;
-use crate::autofix::Fix;
-use crate::checks::{Check, CheckCode, CheckKind, CODE_REDIRECTS};
-use crate::noqa;
-use crate::noqa::{is_file_exempt, Directive};
-use crate::settings::Settings;
-
-// Regex from PEP263.
-static CODING_COMMENT_REGEX: Lazy<Regex> =
-    Lazy::new(|| Regex::new(r"^[ \t\f]*#.*?coding[:=][ \t]*utf-?8").unwrap());
-
-static URL_REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"^https?://\S+$").unwrap());
-
-/// Whether the given line is too long and should be reported.
-fn should_enforce_line_length(line: &str, length: usize, limit: usize) -> bool {
-    if length <= limit {
-        return false;
-    }
-    let mut chunks = line.split_whitespace();
-    let (Some(first), Some(_)) = (chunks.next(), chunks.next()) else {
-        // Single word / no printable chars - no way to make the line shorter
-        return false;
-    };
-
-    // Do not enforce the line length for commented lines that end with a URL
-    // or contain only a single word.
-    !(first == "#" && chunks.last().map_or(true, |c| URL_REGEX.is_match(c)))
-}
-
-pub fn check_lines(
-    checks: &mut Vec<Check>,
-    contents: &str,
-    noqa_line_for: &IntMap<usize, usize>,
-    settings: &Settings,
-    autofix: bool,
-    ignore_noqa: bool,
-) {
-    let enforce_unnecessary_coding_comment = settings.enabled.contains(&CheckCode::UP009);
-    let enforce_line_too_long = settings.enabled.contains(&CheckCode::E501);
-    let enforce_noqa = settings.enabled.contains(&CheckCode::RUF100);
-
-    let mut noqa_directives: IntMap<usize, (Directive, Vec<&str>)> = IntMap::default();
-    let mut line_checks = vec![];
-    let mut ignored = vec![];
-
-    checks.sort_by_key(|check| check.location);
-    let mut checks_iter = checks.iter().enumerate().peekable();
-    if let Some((_index, check)) = checks_iter.peek() {
-        assert!(check.location.row() >= 1);
-    }
-
-    macro_rules! add_if {
-        ($check:expr, $noqa_lineno:expr, $line:expr) => {{
-            match noqa_directives
-                .entry($noqa_lineno)
-                .or_insert_with(|| (noqa::extract_noqa_directive($line), vec![]))
-            {
-                (Directive::All(..), matches) => {
-                    matches.push($check.kind.code().as_ref());
-                    if ignore_noqa {
-                        line_checks.push($check);
-                    }
-                }
-                (Directive::Codes(.., codes), matches) => {
-                    if noqa::includes($check.kind.code(), codes) {
-                        matches.push($check.kind.code().as_ref());
-                        if ignore_noqa {
-                            line_checks.push($check);
-                        }
-                    } else {
-                        line_checks.push($check);
-                    }
-                }
-                (Directive::None, ..) => line_checks.push($check),
-            }
-        }};
-    }
-
-    let lines: Vec<&str> = contents.lines().collect();
-    for (lineno, line) in lines.iter().enumerate() {
-        // If we hit an exemption for the entire file, bail.
-        if is_file_exempt(line) {
-            checks.drain(..);
-            return;
-        }
-
-        // Grab the noqa (logical) line number for the current (physical) line.
-        // If there are newlines at the end of the file, they won't be represented in
-        // `noqa_line_for`, so fallback to the current line.
-        let noqa_lineno = noqa_line_for.get(&(lineno + 1)).unwrap_or(&(lineno + 1)) - 1;
-
-        // Enforce unnecessary coding comments (UP009).
-        if enforce_unnecessary_coding_comment {
-            if lineno < 2 {
-                // PEP3120 makes utf-8 the default encoding.
-                if CODING_COMMENT_REGEX.is_match(line) {
-                    let mut check = Check::new(
-                        CheckKind::PEP3120UnnecessaryCodingComment,
-                        Range {
-                            location: Location::new(lineno + 1, 0),
-                            end_location: Location::new(lineno + 2, 0),
-                        },
-                    );
-                    if autofix && settings.fixable.contains(check.kind.code()) {
-                        check.amend(Fix::deletion(
-                            Location::new(lineno + 1, 0),
-                            Location::new(lineno + 2, 0),
-                        ));
-                    }
-                    add_if!(check, noqa_lineno, lines[noqa_lineno]);
-                }
-            }
-        }
-
-        if enforce_noqa {
-            noqa_directives
-                .entry(noqa_lineno)
-                .or_insert_with(|| (noqa::extract_noqa_directive(lines[noqa_lineno]), vec![]));
-        }
-
-        // Remove any ignored checks.
-        while let Some((index, check)) =
-            checks_iter.next_if(|(_index, check)| check.location.row() == lineno + 1)
-        {
-            let noqa = noqa_directives
-                .entry(noqa_lineno)
-                .or_insert_with(|| (noqa::extract_noqa_directive(lines[noqa_lineno]), vec![]));
-
-            match noqa {
-                (Directive::All(..), matches) => {
-                    matches.push(check.kind.code().as_ref());
-                    ignored.push(index);
-                }
-                (Directive::Codes(.., codes), matches) => {
-                    if noqa::includes(check.kind.code(), codes) {
-                        matches.push(check.kind.code().as_ref());
-                        ignored.push(index);
-                    }
-                }
-                (Directive::None, ..) => {}
-            }
-        }
-
-        // Enforce line length violations (E501).
-        if enforce_line_too_long {
-            let line_length = line.chars().count();
-            if should_enforce_line_length(line, line_length, settings.line_length) {
-                let check = Check::new(
-                    CheckKind::LineTooLong(line_length, settings.line_length),
-                    Range {
-                        location: Location::new(lineno + 1, 0),
-                        end_location: Location::new(lineno + 1, line_length),
-                    },
-                );
-                add_if!(check, noqa_lineno, lines[noqa_lineno]);
-            }
-        }
-    }
-
-    // Enforce newlines at end of files (W292).
-    if settings.enabled.contains(&CheckCode::W292) && !contents.ends_with('\n') {
-        // Note: if `lines.last()` is `None`, then `contents` is empty (and so we don't
-        // want to raise W292 anyway).
-        if let Some(line) = lines.last() {
-            let check = Check::new(
-                CheckKind::NoNewLineAtEndOfFile,
-                Range {
-                    location: Location::new(lines.len(), line.len() + 1),
-                    end_location: Location::new(lines.len(), line.len() + 1),
-                },
-            );
-
-            let lineno = lines.len() - 1;
-            let noqa_lineno = noqa_line_for.get(&(lineno + 1)).unwrap_or(&(lineno + 1)) - 1;
-            add_if!(check, noqa_lineno, lines[noqa_lineno]);
-        }
-    }
-
-    // Enforce that the noqa directive was actually used (RUF100).
-    if enforce_noqa {
-        for (row, (directive, matches)) in noqa_directives {
-            match directive {
-                Directive::All(spaces, start, end) => {
-                    if matches.is_empty() {
-                        let mut check = Check::new(
-                            CheckKind::UnusedNOQA(None),
-                            Range {
-                                location: Location::new(row + 1, start),
-                                end_location: Location::new(row + 1, end),
-                            },
-                        );
-                        if autofix && settings.fixable.contains(check.kind.code()) {
-                            check.amend(Fix::deletion(
-                                Location::new(row + 1, start - spaces),
-                                Location::new(row + 1, lines[row].chars().count()),
-                            ));
-                        }
-                        line_checks.push(check);
-                    }
-                }
-                Directive::Codes(spaces, start, end, codes) => {
-                    let mut invalid_codes = vec![];
-                    let mut valid_codes = vec![];
-                    for code in codes {
-                        let code = CODE_REDIRECTS.get(code).map_or(code, AsRef::as_ref);
-                        if matches.contains(&code) || settings.external.contains(code) {
-                            valid_codes.push(code.to_string());
-                        } else {
-                            invalid_codes.push(code.to_string());
-                        }
-                    }
-
-                    if !invalid_codes.is_empty() {
-                        let mut check = Check::new(
-                            CheckKind::UnusedNOQA(Some(invalid_codes)),
-                            Range {
-                                location: Location::new(row + 1, start),
-                                end_location: Location::new(row + 1, end),
-                            },
-                        );
-                        if autofix && settings.fixable.contains(check.kind.code()) {
-                            if valid_codes.is_empty() {
-                                check.amend(Fix::deletion(
-                                    Location::new(row + 1, start - spaces),
-                                    Location::new(row + 1, lines[row].chars().count()),
-                                ));
-                            } else {
-                                check.amend(Fix::replacement(
-                                    format!("# noqa: {}", valid_codes.join(", ")),
-                                    Location::new(row + 1, start),
-                                    Location::new(row + 1, lines[row].chars().count()),
-                                ));
-                            }
-                        }
-                        line_checks.push(check);
-                    }
-                }
-                Directive::None => {}
-            }
-        }
-    }
-
-    if !ignore_noqa {
-        ignored.sort_unstable();
-        for index in ignored.iter().rev() {
-            checks.swap_remove(*index);
-        }
-    }
-    checks.extend(line_checks);
-}
-
-#[cfg(test)]
-mod tests {
-    use nohash_hasher::IntMap;
-
-    use super::check_lines;
-    use crate::checks::{Check, CheckCode};
-    use crate::settings::Settings;
-
-    #[test]
-    fn e501_non_ascii_char() {
-        let line = "'\u{4e9c}' * 2"; // 7 in UTF-32, 9 in UTF-8.
-        let check_with_max_line_length = |line_length: usize| {
-            let mut checks: Vec<Check> = vec![];
-            check_lines(
-                &mut checks,
-                line,
-                &IntMap::default(),
-                &Settings {
-                    line_length,
-                    ..Settings::for_rule(CheckCode::E501)
-                },
-                true,
-                false,
-            );
-            checks
-        };
-        assert!(!check_with_max_line_length(6).is_empty());
-        assert!(check_with_max_line_length(7).is_empty());
-    }
-}

src/checkers/ast.rs

@@ -25,21 +25,22 @@ use crate::ast::visitor::{walk_excepthandler, Visitor};
 use crate::ast::{branch_detection, cast, helpers, operations, visitor};
 use crate::checks::{Check, CheckCode, CheckKind, DeferralKeyword};
 use crate::docstrings::definition::{Definition, DefinitionKind, Docstring, Documentable};
+use crate::noqa::Directive;
 use crate::python::builtins::{BUILTINS, MAGIC_GLOBALS};
 use crate::python::future::ALL_FEATURE_NAMES;
 use crate::python::typing;
 use crate::python::typing::SubscriptKind;
 use crate::settings::types::PythonVersion;
-use crate::settings::Settings;
+use crate::settings::{flags, Settings};
 use crate::source_code_locator::SourceCodeLocator;
 use crate::vendored::cformat::{CFormatError, CFormatErrorType};
 use crate::visibility::{module_visibility, transition_scope, Modifier, Visibility, VisibleScope};
 use crate::{
     docstrings, flake8_2020, flake8_annotations, flake8_bandit, flake8_blind_except,
-    flake8_boolean_trap, flake8_bugbear, flake8_builtins, flake8_comprehensions, flake8_debugger,
-    flake8_import_conventions, flake8_print, flake8_return, flake8_simplify, flake8_tidy_imports,
-    flake8_unused_arguments, mccabe, pep8_naming, pycodestyle, pydocstyle, pyflakes, pygrep_hooks,
-    pylint, pyupgrade, visibility,
+    flake8_boolean_trap, flake8_bugbear, flake8_builtins, flake8_comprehensions, flake8_datetimez,
+    flake8_debugger, flake8_errmsg, flake8_import_conventions, flake8_print, flake8_return,
+    flake8_simplify, flake8_tidy_imports, flake8_unused_arguments, mccabe, noqa, pandas_vet,
+    pep8_naming, pycodestyle, pydocstyle, pyflakes, pygrep_hooks, pylint, pyupgrade, visibility,
 };
 
 const GLOBAL_SCOPE_INDEX: usize = 0;
@@ -50,8 +51,10 @@ type DeferralContext<'a> = (Vec<usize>, Vec<RefEquality<'a, Stmt>>);
 pub struct Checker<'a> {
     // Input data.
     path: &'a Path,
-    autofix: bool,
+    autofix: flags::Autofix,
+    noqa: flags::Noqa,
     pub(crate) settings: &'a Settings,
+    pub(crate) noqa_line_for: &'a IntMap<usize, usize>,
     pub(crate) locator: &'a SourceCodeLocator<'a>,
     // Computed checks.
     checks: Vec<Check>,
@@ -70,6 +73,7 @@ pub struct Checker<'a> {
     pub(crate) child_to_parent: FxHashMap<RefEquality<'a, Stmt>, RefEquality<'a, Stmt>>,
     pub(crate) bindings: Vec<Binding<'a>>,
     pub(crate) redefinitions: IntMap<usize, Vec<usize>>,
+    exprs: Vec<RefEquality<'a, Expr>>,
     scopes: Vec<Scope<'a>>,
     scope_stack: Vec<usize>,
     dead_scopes: Vec<usize>,
@@ -92,19 +96,23 @@ pub struct Checker<'a> {
     annotations_future_enabled: bool,
     except_handlers: Vec<Vec<Vec<&'a str>>>,
     // Check-specific state.
-    pub(crate) seen_b023: Vec<&'a Expr>,
+    pub(crate) flake8_bugbear_seen: Vec<&'a Expr>,
 }
 
 impl<'a> Checker<'a> {
     pub fn new(
         settings: &'a Settings,
-        autofix: bool,
+        noqa_line_for: &'a IntMap<usize, usize>,
+        autofix: flags::Autofix,
+        noqa: flags::Noqa,
         path: &'a Path,
         locator: &'a SourceCodeLocator,
     ) -> Checker<'a> {
         Checker {
             settings,
+            noqa_line_for,
             autofix,
+            noqa,
             path,
             locator,
             checks: vec![],
@@ -117,6 +125,7 @@ impl<'a> Checker<'a> {
             child_to_parent: FxHashMap::default(),
             bindings: vec![],
             redefinitions: IntMap::default(),
+            exprs: vec![],
             scopes: vec![],
             scope_stack: vec![],
             dead_scopes: vec![],
@@ -142,24 +151,19 @@ impl<'a> Checker<'a> {
             annotations_future_enabled: false,
             except_handlers: vec![],
             // Check-specific state.
-            seen_b023: vec![],
+            flake8_bugbear_seen: vec![],
         }
     }
 
     /// Add a `Check` to the `Checker`.
-    pub(crate) fn add_check(&mut self, check: Check) {
+    pub(crate) fn add_check(&mut self, mut check: Check) {
         // If we're in an f-string, override the location. RustPython doesn't produce
         // reliable locations for expressions within f-strings, so we use the
         // span of the f-string itself as a best-effort default.
-        let check = if let Some(range) = self.in_f_string {
-            Check {
-                location: range.location,
-                end_location: range.end_location,
-                ..check
-            }
-        } else {
-            check
-        };
+        if let Some(range) = self.in_f_string {
+            check.location = range.location;
+            check.end_location = range.end_location;
+        }
         self.checks.push(check);
     }
 
@@ -175,7 +179,16 @@ impl<'a> Checker<'a> {
     pub fn patch(&self, code: &CheckCode) -> bool {
         // TODO(charlie): We can't fix errors in f-strings until RustPython adds
         // location data.
-        self.autofix && self.in_f_string.is_none() && self.settings.fixable.contains(code)
+        matches!(self.autofix, flags::Autofix::Enabled)
+            && self.in_f_string.is_none()
+            && self.settings.fixable.contains(code)
+    }
+
+    /// Return the amended `Range` from a `Located`.
+    pub fn range_for<T>(&self, located: &Located<T>) -> Range {
+        // If we're in an f-string, override the location.
+        self.in_f_string
+            .unwrap_or_else(|| Range::from_located(located))
     }
 
     /// Return `true` if the `Expr` is a reference to `typing.${target}`.
@@ -199,6 +212,30 @@ impl<'a> Checker<'a> {
                 matches!(self.bindings[*index].kind, BindingKind::Builtin)
             })
     }
+
+    /// Return `true` if a `CheckCode` is disabled by a `noqa` directive.
+    pub fn is_ignored(&self, code: &CheckCode, lineno: usize) -> bool {
+        // TODO(charlie): `noqa` directives are mostly enforced in `check_lines.rs`.
+        // However, in rare cases, we need to check them here. For example, when
+        // removing unused imports, we create a single fix that's applied to all
+        // unused members on a single import. We need to pre-emptively omit any
+        // members from the fix that will eventually be excluded by a `noqa`.
+        // Unfortunately, we _do_ want to register a `Check` for each eventually-ignored
+        // import, so that our `noqa` counts are accurate.
+        if matches!(self.noqa, flags::Noqa::Disabled) {
+            return false;
+        }
+        let noqa_lineno = self.noqa_line_for.get(&lineno).unwrap_or(&lineno);
+        let line = self.locator.slice_source_code_range(&Range {
+            location: Location::new(*noqa_lineno, 0),
+            end_location: Location::new(noqa_lineno + 1, 0),
+        });
+        match noqa::extract_noqa_directive(&line) {
+            Directive::None => false,
+            Directive::All(..) => true,
+            Directive::Codes(.., codes) => noqa::includes(code, &codes),
+        }
+    }
 }
 
 impl<'a, 'b> Visitor<'b> for Checker<'a>
@@ -223,10 +260,10 @@ where
             StmtKind::Import { .. } => {
                 self.futures_allowed = false;
             }
-            node => {
+            _ => {
                 self.futures_allowed = false;
                 if !self.seen_import_boundary
-                    && !helpers::is_assignment_to_a_dunder(node)
+                    && !helpers::is_assignment_to_a_dunder(stmt)
                     && !operations::in_nested_block(
                         &mut self.parents.iter().rev().map(|node| node.0),
                     )
@@ -510,7 +547,7 @@ where
                         kind: BindingKind::FunctionDefinition,
                         used: None,
                         range: Range::from_located(stmt),
-                        source: Some(self.current_parent().clone()),
+                        source: Some(self.current_stmt().clone()),
                     },
                 );
             }
@@ -591,6 +628,15 @@ where
                 }
             }
             StmtKind::Import { names } => {
+                if self.settings.enabled.contains(&CheckCode::E401) {
+                    if names.len() > 1 {
+                        self.add_check(Check::new(
+                            CheckKind::MultipleImportsOnOneLine,
+                            Range::from_located(stmt),
+                        ));
+                    }
+                }
+
                 if self.settings.enabled.contains(&CheckCode::E402) {
                     if self.seen_import_boundary && stmt.location.column() == 0 {
                         self.add_check(Check::new(
@@ -615,7 +661,7 @@ where
                                 ),
                                 used: None,
                                 range: Range::from_located(alias),
-                                source: Some(self.current_parent().clone()),
+                                source: Some(self.current_stmt().clone()),
                             },
                         );
                     } else {
@@ -655,7 +701,7 @@ where
                                     None
                                 },
                                 range: Range::from_located(alias),
-                                source: Some(self.current_parent().clone()),
+                                source: Some(self.current_stmt().clone()),
                             },
                         );
                     }
@@ -814,7 +860,7 @@ where
                                     Range::from_located(alias),
                                 )),
                                 range: Range::from_located(alias),
-                                source: Some(self.current_parent().clone()),
+                                source: Some(self.current_stmt().clone()),
                             },
                         );
 
@@ -845,7 +891,7 @@ where
                                 kind: BindingKind::StarImportation(*level, module.clone()),
                                 used: None,
                                 range: Range::from_located(stmt),
-                                source: Some(self.current_parent().clone()),
+                                source: Some(self.current_stmt().clone()),
                             },
                         );
 
@@ -914,7 +960,7 @@ where
                                     None
                                 },
                                 range,
-                                source: Some(self.current_parent().clone()),
+                                source: Some(self.current_stmt().clone()),
                             },
                         );
                     }
@@ -1020,6 +1066,14 @@ where
                         flake8_bugbear::plugins::cannot_raise_literal(self, exc);
                     }
                 }
+                if self.settings.enabled.contains(&CheckCode::EM101)
+                    || self.settings.enabled.contains(&CheckCode::EM102)
+                    || self.settings.enabled.contains(&CheckCode::EM103)
+                {
+                    if let Some(exc) = exc {
+                        flake8_errmsg::plugins::string_in_exception(self, exc);
+                    }
+                }
             }
             StmtKind::AugAssign { target, .. } => {
                 self.handle_node_load(target);
@@ -1097,7 +1151,7 @@ where
                 if self.settings.enabled.contains(&CheckCode::B014)
                     || self.settings.enabled.contains(&CheckCode::B025)
                 {
-                    flake8_bugbear::plugins::duplicate_exceptions(self, stmt, handlers);
+                    flake8_bugbear::plugins::duplicate_exceptions(self, handlers);
                 }
                 if self.settings.enabled.contains(&CheckCode::B013) {
                     flake8_bugbear::plugins::redundant_tuple_in_exception_handler(self, handlers);
@@ -1132,6 +1186,11 @@ where
                         self, stmt, targets, value,
                     );
                 }
+                if self.settings.enabled.contains(&CheckCode::PD901) {
+                    if let Some(check) = pandas_vet::checks::assignment_to_df(targets) {
+                        self.add_check(check);
+                    }
+                }
             }
             StmtKind::AnnAssign { target, value, .. } => {
                 if self.settings.enabled.contains(&CheckCode::E731) {
@@ -1330,7 +1389,7 @@ where
                         kind: BindingKind::ClassDefinition,
                         used: None,
                         range: Range::from_located(stmt),
-                        source: Some(self.current_parent().clone()),
+                        source: Some(self.current_stmt().clone()),
                     },
                 );
             }
@@ -1351,10 +1410,6 @@ where
     }
 
     fn visit_expr(&mut self, expr: &'b Expr) {
-        let prev_in_f_string = self.in_f_string;
-        let prev_in_literal = self.in_literal;
-        let prev_in_type_definition = self.in_type_definition;
-
         if !(self.in_deferred_type_definition || self.in_deferred_string_type_definition)
             && self.in_type_definition
             && self.annotations_future_enabled
@@ -1380,6 +1435,12 @@ where
             return;
         }
 
+        self.push_expr(expr);
+
+        let prev_in_f_string = self.in_f_string;
+        let prev_in_literal = self.in_literal;
+        let prev_in_type_definition = self.in_type_definition;
+
         // Pre-visit.
         match &expr.node {
             ExprKind::Subscript { value, slice, .. } => {
@@ -1482,9 +1543,32 @@ where
                     pyupgrade::plugins::use_pep585_annotation(self, expr, attr);
                 }
 
+                if self.settings.enabled.contains(&CheckCode::UP016) {
+                    pyupgrade::plugins::remove_six_compat(self, expr);
+                }
+
+                if self.settings.enabled.contains(&CheckCode::UP017)
+                    && self.settings.target_version >= PythonVersion::Py311
+                {
+                    pyupgrade::plugins::datetime_utc_alias(self, expr);
+                }
+
                 if self.settings.enabled.contains(&CheckCode::YTT202) {
                     flake8_2020::plugins::name_or_attribute(self, expr);
                 }
+
+                for (code, name) in vec![
+                    (CheckCode::PD007, "ix"),
+                    (CheckCode::PD008, "at"),
+                    (CheckCode::PD009, "iat"),
+                    (CheckCode::PD011, "values"),
+                ] {
+                    if self.settings.enabled.contains(&code) {
+                        if attr == name {
+                            self.add_check(Check::new(code.kind(), Range::from_located(expr)));
+                        };
+                    }
+                }
             }
             ExprKind::Call {
                 func,
@@ -1557,6 +1641,12 @@ where
                 if self.settings.enabled.contains(&CheckCode::UP012) {
                     pyupgrade::plugins::unnecessary_encode_utf8(self, expr, func, args, keywords);
                 }
+                if self.settings.enabled.contains(&CheckCode::UP016) {
+                    pyupgrade::plugins::remove_six_compat(self, expr);
+                }
+                if self.settings.enabled.contains(&CheckCode::UP018) {
+                    pyupgrade::plugins::native_literals(self, expr, func, args, keywords);
+                }
 
                 // flake8-super
                 if self.settings.enabled.contains(&CheckCode::UP008) {
@@ -1567,7 +1657,7 @@ where
                 if self.settings.enabled.contains(&CheckCode::T201)
                     || self.settings.enabled.contains(&CheckCode::T203)
                 {
-                    flake8_print::plugins::print_call(self, expr, func);
+                    flake8_print::plugins::print_call(self, expr, func, keywords);
                 }
 
                 // flake8-bugbear
@@ -1855,9 +1945,112 @@ where
                     }
                 }
 
+                // pandas-vet
+                if self.settings.enabled.contains(&CheckCode::PD002) {
+                    self.add_checks(pandas_vet::checks::inplace_argument(keywords).into_iter());
+                }
+
+                for (code, name) in vec![
+                    (CheckCode::PD003, "isnull"),
+                    (CheckCode::PD004, "notnull"),
+                    (CheckCode::PD010, "pivot"),
+                    (CheckCode::PD010, "unstack"),
+                    (CheckCode::PD012, "read_table"),
+                    (CheckCode::PD013, "stack"),
+                ] {
+                    if self.settings.enabled.contains(&code) {
+                        if let ExprKind::Attribute { attr, .. } = &func.node {
+                            if attr == name {
+                                self.add_check(Check::new(code.kind(), Range::from_located(func)));
+                            };
+                        }
+                    }
+                }
+
+                if self.settings.enabled.contains(&CheckCode::PD015) {
+                    if let Some(check) = pandas_vet::checks::use_of_pd_merge(func) {
+                        self.add_check(check);
+                    };
+                }
+
+                // flake8-datetimez
+                if self.settings.enabled.contains(&CheckCode::DTZ001) {
+                    flake8_datetimez::plugins::call_datetime_without_tzinfo(
+                        self,
+                        func,
+                        args,
+                        keywords,
+                        Range::from_located(expr),
+                    );
+                }
+                if self.settings.enabled.contains(&CheckCode::DTZ002) {
+                    flake8_datetimez::plugins::call_datetime_today(
+                        self,
+                        func,
+                        Range::from_located(expr),
+                    );
+                }
+                if self.settings.enabled.contains(&CheckCode::DTZ003) {
+                    flake8_datetimez::plugins::call_datetime_utcnow(
+                        self,
+                        func,
+                        Range::from_located(expr),
+                    );
+                }
+                if self.settings.enabled.contains(&CheckCode::DTZ004) {
+                    flake8_datetimez::plugins::call_datetime_utcfromtimestamp(
+                        self,
+                        func,
+                        Range::from_located(expr),
+                    );
+                }
+                if self.settings.enabled.contains(&CheckCode::DTZ005) {
+                    flake8_datetimez::plugins::call_datetime_now_without_tzinfo(
+                        self,
+                        func,
+                        args,
+                        keywords,
+                        Range::from_located(expr),
+                    );
+                }
+                if self.settings.enabled.contains(&CheckCode::DTZ006) {
+                    flake8_datetimez::plugins::call_datetime_fromtimestamp(
+                        self,
+                        func,
+                        args,
+                        keywords,
+                        Range::from_located(expr),
+                    );
+                }
+                if self.settings.enabled.contains(&CheckCode::DTZ007) {
+                    flake8_datetimez::plugins::call_datetime_strptime_without_zone(
+                        self,
+                        func,
+                        args,
+                        Range::from_located(expr),
+                    );
+                }
+                if self.settings.enabled.contains(&CheckCode::DTZ011) {
+                    flake8_datetimez::plugins::call_date_today(
+                        self,
+                        func,
+                        Range::from_located(expr),
+                    );
+                }
+                if self.settings.enabled.contains(&CheckCode::DTZ012) {
+                    flake8_datetimez::plugins::call_date_fromtimestamp(
+                        self,
+                        func,
+                        Range::from_located(expr),
+                    );
+                }
+
                 // pygrep-hooks
                 if self.settings.enabled.contains(&CheckCode::PGH001) {
-                    pygrep_hooks::checks::no_eval(self, func);
+                    pygrep_hooks::plugins::no_eval(self, func);
+                }
+                if self.settings.enabled.contains(&CheckCode::PGH002) {
+                    pygrep_hooks::plugins::deprecated_log_warn(self, func);
                 }
 
                 // pylint
@@ -2328,6 +2521,29 @@ where
                         self.visit_expr(value);
                         self.in_type_definition = prev_in_type_definition;
                     }
+                } else if ["Arg", "DefaultArg", "NamedArg", "DefaultNamedArg"]
+                    .iter()
+                    .any(|target| {
+                        match_call_path(&call_path, "mypy_extensions", target, &self.from_imports)
+                    })
+                {
+                    self.visit_expr(func);
+
+                    // Ex) DefaultNamedArg(bool | None, name="some_prop_name")
+                    let mut arguments = args.iter().chain(keywords.iter().map(|keyword| {
+                        let KeywordData { value, .. } = &keyword.node;
+                        value
+                    }));
+                    if let Some(expr) = arguments.next() {
+                        self.in_type_definition = true;
+                        self.visit_expr(expr);
+                        self.in_type_definition = prev_in_type_definition;
+                    }
+                    for expr in arguments {
+                        self.in_type_definition = false;
+                        self.visit_expr(expr);
+                        self.in_type_definition = prev_in_type_definition;
+                    }
                 } else {
                     visitor::walk_expr(self, expr);
                 }
@@ -2407,6 +2623,8 @@ where
         self.in_type_definition = prev_in_type_definition;
         self.in_literal = prev_in_literal;
         self.in_f_string = prev_in_f_string;
+
+        self.pop_expr();
     }
 
     fn visit_excepthandler(&mut self, excepthandler: &'b Excepthandler) {
@@ -2552,7 +2770,7 @@ where
                 kind: BindingKind::Argument,
                 used: None,
                 range: Range::from_located(arg),
-                source: Some(self.current_parent().clone()),
+                source: Some(self.current_stmt().clone()),
             },
         );
 
@@ -2587,7 +2805,17 @@ impl<'a> Checker<'a> {
     }
 
     fn pop_parent(&mut self) {
-        self.parents.pop().expect("Attempted to pop without scope");
+        self.parents.pop().expect("Attempted to pop without parent");
+    }
+
+    fn push_expr(&mut self, expr: &'a Expr) {
+        self.exprs.push(RefEquality(expr));
+    }
+
+    fn pop_expr(&mut self) {
+        self.exprs
+            .pop()
+            .expect("Attempted to pop without expression");
     }
 
     fn push_scope(&mut self, scope: Scope<'a>) {
@@ -2618,6 +2846,36 @@ impl<'a> Checker<'a> {
         }
     }
 
+    /// Return the current `Stmt`.
+    pub fn current_stmt(&self) -> &RefEquality<'a, Stmt> {
+        self.parents.iter().rev().next().expect("No parent found")
+    }
+
+    /// Return the parent `Stmt` of the current `Stmt`, if any.
+    pub fn current_stmt_parent(&self) -> Option<&RefEquality<'a, Stmt>> {
+        self.parents.iter().rev().nth(1)
+    }
+
+    /// Return the grandparent `Stmt` of the current `Stmt`, if any.
+    pub fn current_stmt_grandparent(&self) -> Option<&RefEquality<'a, Stmt>> {
+        self.parents.iter().rev().nth(2)
+    }
+
+    /// Return the current `Expr`.
+    pub fn current_expr(&self) -> Option<&RefEquality<'a, Expr>> {
+        self.exprs.iter().rev().next()
+    }
+
+    /// Return the parent `Expr` of the current `Expr`.
+    pub fn current_expr_parent(&self) -> Option<&RefEquality<'a, Expr>> {
+        self.exprs.iter().rev().nth(1)
+    }
+
+    /// Return the grandparent `Expr` of the current `Expr`.
+    pub fn current_expr_grandparent(&self) -> Option<&RefEquality<'a, Expr>> {
+        self.exprs.iter().rev().nth(2)
+    }
+
     pub fn current_scope(&self) -> &Scope {
         &self.scopes[*(self.scope_stack.last().expect("No current scope found"))]
     }
@@ -2629,14 +2887,6 @@ impl<'a> Checker<'a> {
             .map(|index| &self.scopes[*index])
     }
 
-    pub fn current_parent(&self) -> &RefEquality<'a, Stmt> {
-        self.parents.iter().rev().next().expect("No parent found")
-    }
-
-    pub fn current_grandparent(&self) -> Option<&RefEquality<'a, Stmt>> {
-        self.parents.iter().rev().nth(1)
-    }
-
     fn add_binding<'b>(&mut self, name: &'b str, binding: Binding<'a>)
     where
         'b: 'a,
@@ -2866,7 +3116,7 @@ impl<'a> Checker<'a> {
     where
         'b: 'a,
     {
-        let parent = self.current_parent().0;
+        let parent = self.current_stmt().0;
 
         if self.settings.enabled.contains(&CheckCode::F823) {
             let scopes: Vec<&Scope> = self
@@ -2911,7 +3161,7 @@ impl<'a> Checker<'a> {
                     kind: BindingKind::Annotation,
                     used: None,
                     range: Range::from_located(expr),
-                    source: Some(self.current_parent().clone()),
+                    source: Some(self.current_stmt().clone()),
                 },
             );
             return;
@@ -2928,7 +3178,7 @@ impl<'a> Checker<'a> {
                     kind: BindingKind::LoopVar,
                     used: None,
                     range: Range::from_located(expr),
-                    source: Some(self.current_parent().clone()),
+                    source: Some(self.current_stmt().clone()),
                 },
             );
             return;
@@ -2941,7 +3191,7 @@ impl<'a> Checker<'a> {
                     kind: BindingKind::Binding,
                     used: None,
                     range: Range::from_located(expr),
-                    source: Some(self.current_parent().clone()),
+                    source: Some(self.current_stmt().clone()),
                 },
             );
             return;
@@ -2991,7 +3241,7 @@ impl<'a> Checker<'a> {
                         )),
                         used: None,
                         range: Range::from_located(expr),
-                        source: Some(self.current_parent().clone()),
+                        source: Some(self.current_stmt().clone()),
                     },
                 );
                 return;
@@ -3004,7 +3254,7 @@ impl<'a> Checker<'a> {
                 kind: BindingKind::Assignment,
                 used: None,
                 range: Range::from_located(expr),
-                source: Some(self.current_parent().clone()),
+                source: Some(self.current_stmt().clone()),
             },
         );
     }
@@ -3329,6 +3579,8 @@ impl<'a> Checker<'a> {
                     (&'a RefEquality<'b, Stmt>, Option<&'a RefEquality<'b, Stmt>>);
 
                 let mut unused: FxHashMap<BindingContext, Vec<UnusedImport>> = FxHashMap::default();
+                let mut ignored: FxHashMap<BindingContext, Vec<UnusedImport>> =
+                    FxHashMap::default();
 
                 for (name, index) in scope
                     .values
@@ -3353,12 +3605,21 @@ impl<'a> Checker<'a> {
 
                     let defined_by = binding.source.as_ref().unwrap();
                     let defined_in = self.child_to_parent.get(defined_by);
-                    unused
-                        .entry((defined_by, defined_in))
-                        .or_default()
-                        .push((full_name, &binding.range));
+                    if self.is_ignored(&CheckCode::F401, binding.range.location.row()) {
+                        ignored
+                            .entry((defined_by, defined_in))
+                            .or_default()
+                            .push((full_name, &binding.range));
+                    } else {
+                        unused
+                            .entry((defined_by, defined_in))
+                            .or_default()
+                            .push((full_name, &binding.range));
+                    }
                 }
 
+                let ignore_init =
+                    self.settings.ignore_init_module_imports && self.path.ends_with("__init__.py");
                 for ((defined_by, defined_in), unused_imports) in unused
                     .into_iter()
                     .sorted_by_key(|((defined_by, _), _)| defined_by.0.location)
@@ -3366,17 +3627,15 @@ impl<'a> Checker<'a> {
                     let child = defined_by.0;
                     let parent = defined_in.map(|defined_in| defined_in.0);
 
-                    let ignore_init = self.settings.ignore_init_module_imports
-                        && self.path.ends_with("__init__.py");
                     let fix = if !ignore_init && self.patch(&CheckCode::F401) {
                         let deleted: Vec<&Stmt> =
                             self.deletions.iter().map(|node| node.0).collect();
                         match pyflakes::fixes::remove_unused_imports(
-                            self.locator,
                             &unused_imports,
                             child,
                             parent,
                             &deleted,
+                            self.locator,
                         ) {
                             Ok(fix) => {
                                 if fix.content.is_empty() || fix.content == "pass" {
@@ -3404,6 +3663,17 @@ impl<'a> Checker<'a> {
                         checks.push(check);
                     }
                 }
+                for (_, unused_imports) in ignored
+                    .into_iter()
+                    .sorted_by_key(|((defined_by, _), _)| defined_by.0.location)
+                {
+                    for (full_name, range) in unused_imports {
+                        checks.push(Check::new(
+                            CheckKind::UnusedImport(full_name.clone(), ignore_init),
+                            *range,
+                        ));
+                    }
+                }
             }
         }
         self.add_checks(checks.into_iter());
@@ -3638,11 +3908,13 @@ impl<'a> Checker<'a> {
 pub fn check_ast(
     python_ast: &Suite,
     locator: &SourceCodeLocator,
+    noqa_line_for: &IntMap<usize, usize>,
     settings: &Settings,
-    autofix: bool,
+    autofix: flags::Autofix,
+    noqa: flags::Noqa,
     path: &Path,
 ) -> Vec<Check> {
-    let mut checker = Checker::new(settings, autofix, path, locator);
+    let mut checker = Checker::new(settings, noqa_line_for, autofix, noqa, path, locator);
     checker.push_scope(Scope::new(ScopeKind::Module));
     checker.bind_builtins();
 

src/checkers/imports.rs

@@ -9,19 +9,22 @@ use crate::checks::Check;
 use crate::directives::IsortDirectives;
 use crate::isort;
 use crate::isort::track::ImportTracker;
-use crate::settings::Settings;
+use crate::settings::{flags, Settings};
 use crate::source_code_locator::SourceCodeLocator;
 
 fn check_import_blocks(
     tracker: ImportTracker,
     locator: &SourceCodeLocator,
     settings: &Settings,
-    autofix: bool,
+    autofix: flags::Autofix,
+    package: Option<&Path>,
 ) -> Vec<Check> {
     let mut checks = vec![];
     for block in tracker.into_iter() {
         if !block.imports.is_empty() {
-            if let Some(check) = isort::plugins::check_imports(&block, locator, settings, autofix) {
+            if let Some(check) =
+                isort::plugins::check_imports(&block, locator, settings, autofix, package)
+            {
                 checks.push(check);
             }
         }
@@ -34,12 +37,13 @@ pub fn check_imports(
     locator: &SourceCodeLocator,
     directives: &IsortDirectives,
     settings: &Settings,
-    autofix: bool,
+    autofix: flags::Autofix,
     path: &Path,
+    package: Option<&Path>,
 ) -> Vec<Check> {
     let mut tracker = ImportTracker::new(locator, directives, path);
     for stmt in python_ast {
         tracker.visit_stmt(stmt);
     }
-    check_import_blocks(tracker, locator, settings, autofix)
+    check_import_blocks(tracker, locator, settings, autofix, package)
 }

src/checkers/lines.rs

@@ -0,0 +1,94 @@
+//! Lint rules based on checking raw physical lines.
+
+use crate::checks::{Check, CheckCode};
+use crate::pycodestyle::checks::{line_too_long, no_newline_at_end_of_file};
+use crate::pygrep_hooks::plugins::blanket_type_ignore;
+use crate::pyupgrade::checks::unnecessary_coding_comment;
+use crate::settings::{flags, Settings};
+
+pub fn check_lines(
+    contents: &str,
+    commented_lines: &[usize],
+    settings: &Settings,
+    autofix: flags::Autofix,
+) -> Vec<Check> {
+    let mut checks: Vec<Check> = vec![];
+
+    let enforce_unnecessary_coding_comment = settings.enabled.contains(&CheckCode::UP009);
+    let enforce_line_too_long = settings.enabled.contains(&CheckCode::E501);
+    let enforce_no_newline_at_end_of_file = settings.enabled.contains(&CheckCode::W292);
+    let enforce_blanket_type_ignore = settings.enabled.contains(&CheckCode::PGH003);
+
+    let mut commented_lines_iter = commented_lines.iter().peekable();
+    for (index, line) in contents.lines().enumerate() {
+        while commented_lines_iter
+            .next_if(|lineno| &(index + 1) == *lineno)
+            .is_some()
+        {
+            if enforce_unnecessary_coding_comment {
+                if index < 2 {
+                    if let Some(check) = unnecessary_coding_comment(
+                        index,
+                        line,
+                        matches!(autofix, flags::Autofix::Enabled)
+                            && settings.fixable.contains(&CheckCode::UP009),
+                    ) {
+                        checks.push(check);
+                    }
+                }
+            }
+
+            if enforce_blanket_type_ignore {
+                if commented_lines.contains(&(index + 1)) {
+                    if let Some(check) = blanket_type_ignore(index, line) {
+                        checks.push(check);
+                    }
+                }
+            }
+        }
+
+        if enforce_line_too_long {
+            if let Some(check) = line_too_long(index, line, settings.line_length) {
+                checks.push(check);
+            }
+        }
+    }
+
+    if enforce_no_newline_at_end_of_file {
+        if let Some(check) = no_newline_at_end_of_file(
+            contents,
+            matches!(autofix, flags::Autofix::Enabled)
+                && settings.fixable.contains(&CheckCode::W292),
+        ) {
+            checks.push(check);
+        }
+    }
+
+    checks
+}
+
+#[cfg(test)]
+mod tests {
+
+    use super::check_lines;
+    use crate::checks::CheckCode;
+    use crate::settings::{flags, Settings};
+
+    #[test]
+    fn e501_non_ascii_char() {
+        let line = "'\u{4e9c}' * 2"; // 7 in UTF-32, 9 in UTF-8.
+        let check_with_max_line_length = |line_length: usize| {
+            check_lines(
+                line,
+                &[],
+                &Settings {
+                    line_length,
+                    ..Settings::for_rule(CheckCode::E501)
+                },
+                flags::Autofix::Enabled,
+            )
+        };
+        assert!(!check_with_max_line_length(6).is_empty());
+        assert!(check_with_max_line_length(7).is_empty());
+    }
+}

src/checkers/mod.rs

@@ -0,0 +1,5 @@
+pub mod ast;
+pub mod imports;
+pub mod lines;
+pub mod noqa;
+pub mod tokens;

src/checkers/noqa.rs

@@ -0,0 +1,186 @@
+//! `NoQA` enforcement and validation.
+
+use std::str::FromStr;
+
+use nohash_hasher::IntMap;
+use rustpython_parser::ast::Location;
+
+use crate::ast::types::Range;
+use crate::autofix::Fix;
+use crate::checks::{Check, CheckCode, CheckKind, UnusedCodes, CODE_REDIRECTS};
+use crate::noqa;
+use crate::noqa::{is_file_exempt, Directive};
+use crate::settings::{flags, Settings};
+
+pub fn check_noqa(
+    checks: &mut Vec<Check>,
+    contents: &str,
+    commented_lines: &[usize],
+    noqa_line_for: &IntMap<usize, usize>,
+    settings: &Settings,
+    autofix: flags::Autofix,
+) {
+    let mut noqa_directives: IntMap<usize, (Directive, Vec<&str>)> = IntMap::default();
+    let mut ignored = vec![];
+
+    let enforce_noqa = settings.enabled.contains(&CheckCode::RUF100);
+
+    checks.sort_by_key(|check| check.location);
+    let mut checks_iter = checks.iter().enumerate().peekable();
+    if let Some((_index, check)) = checks_iter.peek() {
+        assert!(check.location.row() >= 1);
+    }
+
+    let lines: Vec<&str> = contents.lines().collect();
+    for lineno in commented_lines {
+        // If we hit an exemption for the entire file, bail.
+        if is_file_exempt(lines[lineno - 1]) {
+            checks.drain(..);
+            return;
+        }
+
+        if enforce_noqa {
+            noqa_directives
+                .entry(lineno - 1)
+                .or_insert_with(|| (noqa::extract_noqa_directive(lines[lineno - 1]), vec![]));
+        }
+
+        // Remove any ignored checks.
+        while let Some((index, check)) =
+            checks_iter.next_if(|(_index, check)| check.location.row() <= *lineno)
+        {
+            // Grab the noqa (logical) line number for the current (physical) line.
+            // If there are newlines at the end of the file, they won't be represented in
+            // `noqa_line_for`, so fallback to the current line.
+            let check_lineno = check.location.row();
+            let noqa_lineno = noqa_line_for.get(&check_lineno).unwrap_or(&check_lineno);
+            if noqa_lineno == lineno {
+                let noqa = noqa_directives.entry(noqa_lineno - 1).or_insert_with(|| {
+                    (noqa::extract_noqa_directive(lines[noqa_lineno - 1]), vec![])
+                });
+                match noqa {
+                    (Directive::All(..), matches) => {
+                        matches.push(check.kind.code().as_ref());
+                        ignored.push(index);
+                    }
+                    (Directive::Codes(.., codes), matches) => {
+                        if noqa::includes(check.kind.code(), codes) {
+                            matches.push(check.kind.code().as_ref());
+                            ignored.push(index);
+                        }
+                    }
+                    (Directive::None, ..) => {}
+                }
+            }
+        }
+    }
+
+    // Enforce that the noqa directive was actually used (RUF100).
+    if enforce_noqa {
+        for (row, (directive, matches)) in noqa_directives {
+            match directive {
+                Directive::All(spaces, start, end) => {
+                    if matches.is_empty() {
+                        let mut check = Check::new(
+                            CheckKind::UnusedNOQA(None),
+                            Range {
+                                location: Location::new(row + 1, start),
+                                end_location: Location::new(row + 1, end),
+                            },
+                        );
+                        if matches!(autofix, flags::Autofix::Enabled)
+                            && settings.fixable.contains(check.kind.code())
+                        {
+                            check.amend(Fix::deletion(
+                                Location::new(row + 1, start - spaces),
+                                Location::new(row + 1, lines[row].chars().count()),
+                            ));
+                        }
+                        checks.push(check);
+                    }
+                }
+                Directive::Codes(spaces, start, end, codes) => {
+                    let mut disabled_codes = vec![];
+                    let mut unknown_codes = vec![];
+                    let mut unmatched_codes = vec![];
+                    let mut valid_codes = vec![];
+                    let mut self_ignore = false;
+                    for code in codes {
+                        let code = CODE_REDIRECTS.get(code).map_or(code, AsRef::as_ref);
+                        if code == CheckCode::RUF100.as_ref() {
+                            self_ignore = true;
+                            break;
+                        }
+
+                        if matches.contains(&code) || settings.external.contains(code) {
+                            valid_codes.push(code);
+                        } else {
+                            if let Ok(check_code) = CheckCode::from_str(code) {
+                                if settings.enabled.contains(&check_code) {
+                                    unmatched_codes.push(code);
+                                } else {
+                                    disabled_codes.push(code);
+                                }
+                            } else {
+                                unknown_codes.push(code);
+                            }
+                        }
+                    }
+
+                    if self_ignore {
+                        continue;
+                    }
+
+                    if !(disabled_codes.is_empty()
+                        && unknown_codes.is_empty()
+                        && unmatched_codes.is_empty())
+                    {
+                        let mut check = Check::new(
+                            CheckKind::UnusedNOQA(Some(UnusedCodes {
+                                disabled: disabled_codes
+                                    .iter()
+                                    .map(|code| (*code).to_string())
+                                    .collect(),
+                                unknown: unknown_codes
+                                    .iter()
+                                    .map(|code| (*code).to_string())
+                                    .collect(),
+                                unmatched: unmatched_codes
+                                    .iter()
+                                    .map(|code| (*code).to_string())
+                                    .collect(),
+                            })),
+                            Range {
+                                location: Location::new(row + 1, start),
+                                end_location: Location::new(row + 1, end),
+                            },
+                        );
+                        if matches!(autofix, flags::Autofix::Enabled)
+                            && settings.fixable.contains(check.kind.code())
+                        {
+                            if valid_codes.is_empty() {
+                                check.amend(Fix::deletion(
+                                    Location::new(row + 1, start - spaces),
+                                    Location::new(row + 1, lines[row].chars().count()),
+                                ));
+                            } else {
+                                check.amend(Fix::replacement(
+                                    format!("# noqa: {}", valid_codes.join(", ")),
+                                    Location::new(row + 1, start),
+                                    Location::new(row + 1, lines[row].chars().count()),
+                                ));
+                            }
+                        }
+                        checks.push(check);
+                    }
+                }
+                Directive::None => {}
+            }
+        }
+    }
+
+    ignored.sort_unstable();
+    for index in ignored.iter().rev() {
+        checks.swap_remove(*index);
+    }
+}

src/checkers/tokens.rs

@@ -5,6 +5,7 @@ use rustpython_parser::lexer::{LexResult, Tok};
 use crate::checks::{Check, CheckCode};
 use crate::lex::docstring_detection::StateMachine;
 use crate::ruff::checks::Context;
+use crate::settings::flags;
 use crate::source_code_locator::SourceCodeLocator;
 use crate::{eradicate, flake8_quotes, pycodestyle, ruff, Settings};
 
@@ -12,7 +13,7 @@ pub fn check_tokens(
     locator: &SourceCodeLocator,
     tokens: &[LexResult],
     settings: &Settings,
-    autofix: bool,
+    autofix: flags::Autofix,
 ) -> Vec<Check> {
     let mut checks: Vec<Check> = vec![];
 
@@ -88,7 +89,11 @@ pub fn check_tokens(
         if enforce_invalid_escape_sequence {
             if matches!(tok, Tok::String { .. }) {
                 checks.extend(pycodestyle::checks::invalid_escape_sequence(
-                    locator, start, end,
+                    locator,
+                    start,
+                    end,
+                    matches!(autofix, flags::Autofix::Enabled)
+                        && settings.fixable.contains(&CheckCode::W605),
                 ));
             }
         }

src/cli.rs

@@ -92,6 +92,12 @@ pub struct Cli {
     respect_gitignore: bool,
     #[clap(long, overrides_with("respect_gitignore"), hide = true)]
     no_respect_gitignore: bool,
+    /// Enforce exclusions, even for paths passed to Ruff directly on the
+    /// command-line.
+    #[arg(long, overrides_with("no_show_source"))]
+    force_exclude: bool,
+    #[clap(long, overrides_with("force_exclude"), hide = true)]
+    no_force_exclude: bool,
     /// See the files Ruff will be run against with the current settings.
     #[arg(long)]
     pub show_files: bool,
@@ -120,13 +126,16 @@ pub struct Cli {
     pub autoformat: bool,
     /// The name of the file when passing it through stdin.
     #[arg(long)]
-    pub stdin_filename: Option<String>,
+    pub stdin_filename: Option<PathBuf>,
     /// Explain a rule.
     #[arg(long)]
     pub explain: Option<CheckCode>,
     /// Generate shell completion
     #[arg(long, hide = true, value_name = "SHELL")]
     pub generate_shell_completion: Option<clap_complete_command::Shell>,
+    /// Path to the cache directory.
+    #[arg(long)]
+    pub cache_dir: Option<PathBuf>,
 }
 
 impl Cli {
@@ -173,6 +182,8 @@ impl Cli {
                 // TODO(charlie): Included in `pyproject.toml`, but not inherited.
                 fix: resolve_bool_arg(self.fix, self.no_fix),
                 format: self.format,
+                force_exclude: resolve_bool_arg(self.force_exclude, self.no_force_exclude),
+                cache_dir: self.cache_dir,
             },
         )
     }
@@ -203,7 +214,7 @@ pub struct Arguments {
     pub show_files: bool,
     pub show_settings: bool,
     pub silent: bool,
-    pub stdin_filename: Option<String>,
+    pub stdin_filename: Option<PathBuf>,
     pub verbose: bool,
     pub watch: bool,
 }
@@ -230,6 +241,8 @@ pub struct Overrides {
     // TODO(charlie): Captured in pyproject.toml as a default, but not part of `Settings`.
     pub fix: Option<bool>,
     pub format: Option<SerializationFormat>,
+    pub force_exclude: Option<bool>,
+    pub cache_dir: Option<PathBuf>,
 }
 
 /// Map the CLI settings to a `LogLevel`.

src/commands.rs

@@ -17,9 +17,10 @@ use crate::cli::Overrides;
 use crate::iterators::par_iter;
 use crate::linter::{add_noqa_to_path, autoformat_path, lint_path, lint_stdin, Diagnostics};
 use crate::message::Message;
-use crate::resolver;
 use crate::resolver::{FileDiscovery, PyprojectDiscovery};
+use crate::settings::flags;
 use crate::settings::types::SerializationFormat;
+use crate::{cache, packages, resolver};
 
 /// Run the linter over a collection of files.
 pub fn run(
@@ -27,24 +28,61 @@ pub fn run(
     pyproject_strategy: &PyprojectDiscovery,
     file_strategy: &FileDiscovery,
     overrides: &Overrides,
-    cache: bool,
-    autofix: &fixer::Mode,
+    cache: flags::Cache,
+    autofix: fixer::Mode,
 ) -> Result<Diagnostics> {
-    // Collect all the files to check.
+    // Collect all the Python files to check.
     let start = Instant::now();
     let (paths, resolver) =
         resolver::python_files_in_path(files, pyproject_strategy, file_strategy, overrides)?;
     let duration = start.elapsed();
     debug!("Identified files to lint in: {:?}", duration);
 
+    // Discover the package root for each Python file.
+    let package_roots = packages::detect_package_roots(
+        &paths
+            .iter()
+            .flatten()
+            .map(ignore::DirEntry::path)
+            .collect::<Vec<_>>(),
+    );
+
+    // Initialize the cache.
+    if matches!(cache, flags::Cache::Enabled) {
+        match &pyproject_strategy {
+            PyprojectDiscovery::Fixed(settings) => {
+                if let Err(e) = cache::init(&settings.cache_dir) {
+                    error!(
+                        "Failed to initialize cache at {}: {e:?}",
+                        settings.cache_dir.to_string_lossy()
+                    );
+                }
+            }
+            PyprojectDiscovery::Hierarchical(default) => {
+                for settings in std::iter::once(default).chain(resolver.iter()) {
+                    if let Err(e) = cache::init(&settings.cache_dir) {
+                        error!(
+                            "Failed to initialize cache at {}: {e:?}",
+                            settings.cache_dir.to_string_lossy()
+                        );
+                    }
+                }
+            }
+        }
+    };
+
     let start = Instant::now();
     let mut diagnostics: Diagnostics = par_iter(&paths)
         .map(|entry| {
             match entry {
                 Ok(entry) => {
                     let path = entry.path();
+                    let package = path
+                        .parent()
+                        .and_then(|parent| package_roots.get(parent))
+                        .and_then(|package| *package);
                     let settings = resolver.resolve(path, pyproject_strategy);
-                    lint_path(path, settings, &cache.into(), autofix)
+                    lint_path(path, package, settings, cache, autofix)
                         .map_err(|e| (Some(path.to_owned()), e.to_string()))
                 }
                 Err(e) => Err((
@@ -100,16 +138,26 @@ fn read_from_stdin() -> Result<String> {
 
 /// Run the linter over a single file, read from `stdin`.
 pub fn run_stdin(
-    strategy: &PyprojectDiscovery,
-    filename: &Path,
-    autofix: &fixer::Mode,
+    filename: Option<&Path>,
+    pyproject_strategy: &PyprojectDiscovery,
+    file_strategy: &FileDiscovery,
+    overrides: &Overrides,
+    autofix: fixer::Mode,
 ) -> Result<Diagnostics> {
-    let stdin = read_from_stdin()?;
-    let settings = match strategy {
+    if let Some(filename) = filename {
+        if !resolver::python_file_at_path(filename, pyproject_strategy, file_strategy, overrides)? {
+            return Ok(Diagnostics::default());
+        }
+    }
+    let settings = match pyproject_strategy {
         PyprojectDiscovery::Fixed(settings) => settings,
         PyprojectDiscovery::Hierarchical(settings) => settings,
     };
-    let mut diagnostics = lint_stdin(filename, &stdin, settings, autofix)?;
+    let package_root = filename
+        .and_then(Path::parent)
+        .and_then(packages::detect_package_root);
+    let stdin = read_from_stdin()?;
+    let mut diagnostics = lint_stdin(filename, package_root, &stdin, settings, autofix)?;
     diagnostics.messages.sort_unstable();
     Ok(diagnostics)
 }

src/directives.rs

@@ -37,6 +37,7 @@ pub struct IsortDirectives {
 }
 
 pub struct Directives {
+    pub commented_lines: Vec<usize>,
     pub noqa_line_for: IntMap<usize, usize>,
     pub isort: IsortDirectives,
 }
@@ -47,6 +48,7 @@ pub fn extract_directives(
     flags: Flags,
 ) -> Directives {
     Directives {
+        commented_lines: extract_commented_lines(lxr),
         noqa_line_for: if flags.contains(Flags::NOQA) {
             extract_noqa_line_for(lxr)
         } else {
@@ -60,6 +62,16 @@ pub fn extract_directives(
     }
 }
 
+pub fn extract_commented_lines(lxr: &[LexResult]) -> Vec<usize> {
+    let mut commented_lines = Vec::new();
+    for (start, tok, ..) in lxr.iter().flatten() {
+        if matches!(tok, Tok::Comment) {
+            commented_lines.push(start.row());
+        }
+    }
+    commented_lines
+}
+
 /// Extract a mapping from logical line to noqa line.
 pub fn extract_noqa_line_for(lxr: &[LexResult]) -> IntMap<usize, usize> {
     let mut noqa_line_for: IntMap<usize, usize> = IntMap::default();

src/eradicate/checks.rs

@@ -4,6 +4,7 @@ use crate::ast::types::Range;
 use crate::autofix::Fix;
 use crate::checks::{CheckCode, CheckKind};
 use crate::eradicate::detection::comment_contains_code;
+use crate::settings::flags;
 use crate::{Check, Settings, SourceCodeLocator};
 
 fn is_standalone_comment(line: &str) -> bool {
@@ -23,7 +24,7 @@ pub fn commented_out_code(
     start: Location,
     end: Location,
     settings: &Settings,
-    autofix: bool,
+    autofix: flags::Autofix,
 ) -> Option<Check> {
     let location = Location::new(start.row(), 0);
     let end_location = Location::new(end.row() + 1, 0);
@@ -41,7 +42,9 @@ pub fn commented_out_code(
                 end_location: end,
             },
         );
-        if autofix && settings.fixable.contains(&CheckCode::ERA001) {
+        if matches!(autofix, flags::Autofix::Enabled)
+            && settings.fixable.contains(&CheckCode::ERA001)
+        {
             check.amend(Fix::deletion(location, end_location));
         }
         Some(check)

src/eradicate/mod.rs

@@ -21,7 +21,6 @@ mod tests {
                 .join(path)
                 .as_path(),
             &settings::Settings::for_rule(check_code),
-            true,
         )?;
         checks.sort_by_key(|check| check.location);
         insta::assert_yaml_snapshot!(snapshot, checks);

src/flake8_2020/mod.rs

@@ -29,7 +29,6 @@ mod tests {
                 .join(path)
                 .as_path(),
             &settings::Settings::for_rule(check_code),
-            true,
         )?;
         checks.sort_by_key(|check| check.location);
         insta::assert_yaml_snapshot!(snapshot, checks);

src/flake8_2020/plugins.rs

@@ -3,7 +3,7 @@ use rustpython_ast::{Cmpop, Constant, Expr, ExprKind, Located};
 
 use crate::ast::helpers::match_module_member;
 use crate::ast::types::Range;
-use crate::check_ast::Checker;
+use crate::checkers::ast::Checker;
 use crate::checks::{Check, CheckCode, CheckKind};
 
 fn is_sys(checker: &Checker, expr: &Expr, target: &str) -> bool {

src/flake8_annotations/fixes.rs

@@ -0,0 +1,45 @@
+use anyhow::{bail, Result};
+use rustpython_ast::Stmt;
+use rustpython_parser::lexer;
+use rustpython_parser::lexer::Tok;
+
+use crate::ast::helpers;
+use crate::ast::types::Range;
+use crate::autofix::Fix;
+use crate::source_code_locator::SourceCodeLocator;
+
+/// ANN204
+pub fn add_return_none_annotation(locator: &SourceCodeLocator, stmt: &Stmt) -> Result<Fix> {
+    let range = Range::from_located(stmt);
+    let contents = locator.slice_source_code_range(&range);
+
+    // Find the colon (following the `def` keyword).
+    let mut seen_lpar = false;
+    let mut seen_rpar = false;
+    let mut count: usize = 0;
+    for (start, tok, ..) in lexer::make_tokenizer(&contents).flatten() {
+        if seen_lpar && seen_rpar {
+            if matches!(tok, Tok::Colon) {
+                return Ok(Fix::insertion(
+                    " -> None".to_string(),
+                    helpers::to_absolute(start, range.location),
+                ));
+            }
+        }
+
+        if matches!(tok, Tok::Lpar) {
+            if count == 0 {
+                seen_lpar = true;
+            }
+            count += 1;
+        }
+        if matches!(tok, Tok::Rpar) {
+            count -= 1;
+            if count == 0 {
+                seen_rpar = true;
+            }
+        }
+    }
+
+    bail!("Unable to locate colon in function definition");
+}

src/flake8_annotations/helpers.rs

@@ -1,7 +1,7 @@
 use rustpython_ast::{Arguments, Expr, Stmt, StmtKind};
 
 use crate::ast::cast;
-use crate::check_ast::Checker;
+use crate::checkers::ast::Checker;
 use crate::docstrings::definition::{Definition, DefinitionKind};
 use crate::visibility;
 

src/flake8_annotations/mod.rs

@@ -1,3 +1,4 @@
+mod fixes;
 pub mod helpers;
 pub mod plugins;
 pub mod settings;
@@ -31,7 +32,6 @@ mod tests {
                     CheckCode::ANN401,
                 ])
             },
-            true,
         )?;
         checks.sort_by_key(|check| check.location);
         insta::assert_yaml_snapshot!(checks);
@@ -57,7 +57,6 @@ mod tests {
                     CheckCode::ANN102,
                 ])
             },
-            true,
         )?;
         checks.sort_by_key(|check| check.location);
         insta::assert_yaml_snapshot!(checks);
@@ -83,7 +82,6 @@ mod tests {
                     CheckCode::ANN206,
                 ])
             },
-            true,
         )?;
         checks.sort_by_key(|check| check.location);
         insta::assert_yaml_snapshot!(checks);
@@ -109,7 +107,6 @@ mod tests {
                     CheckCode::ANN206,
                 ])
             },
-            true,
         )?;
         checks.sort_by_key(|check| check.location);
         insta::assert_yaml_snapshot!(checks);
@@ -129,7 +126,6 @@ mod tests {
                 },
                 ..Settings::for_rules(vec![CheckCode::ANN401])
             },
-            true,
         )?;
         checks.sort_by_key(|check| check.location);
         insta::assert_yaml_snapshot!(checks);
@@ -149,7 +145,6 @@ mod tests {
                     CheckCode::ANN206,
                 ])
             },
-            true,
         )?;
         checks.sort_by_key(|check| check.location);
         insta::assert_yaml_snapshot!(checks);

src/flake8_annotations/plugins.rs

@@ -1,11 +1,13 @@
+use log::error;
 use rustpython_ast::{Constant, Expr, ExprKind, Stmt, StmtKind};
 
 use crate::ast::types::Range;
 use crate::ast::visitor::Visitor;
 use crate::ast::{cast, visitor};
-use crate::check_ast::Checker;
+use crate::checkers::ast::Checker;
 use crate::checks::{CheckCode, CheckKind};
 use crate::docstrings::definition::{Definition, DefinitionKind};
+use crate::flake8_annotations::fixes;
 use crate::flake8_annotations::helpers::match_function_def;
 use crate::visibility::Visibility;
 use crate::{visibility, Check};
@@ -295,8 +297,8 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
                     check_dynamically_typed(checker, expr, || name.to_string());
                 }
             } else {
-                // Allow omission of return annotation in `__init__` functions, if the function
-                // only returns `None` (explicitly or implicitly).
+                // Allow omission of return annotation if the function only returns `None`
+                // (explicitly or implicitly).
                 if checker.settings.flake8_annotations.suppress_none_returning
                     && is_none_returning(body)
                 {
@@ -317,13 +319,6 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
                             Range::from_located(stmt),
                         ));
                     }
-                } else if visibility::is_magic(stmt) {
-                    if checker.settings.enabled.contains(&CheckCode::ANN204) {
-                        checker.add_check(Check::new(
-                            CheckKind::MissingReturnTypeMagicMethod(name.to_string()),
-                            Range::from_located(stmt),
-                        ));
-                    }
                 } else if visibility::is_init(stmt) {
                     // Allow omission of return annotation in `__init__` functions, as long as at
                     // least one argument is typed.
@@ -331,12 +326,26 @@ pub fn definition(checker: &mut Checker, definition: &Definition, visibility: &V
                         if !(checker.settings.flake8_annotations.mypy_init_return
                             && has_any_typed_arg)
                         {
-                            checker.add_check(Check::new(
-                                CheckKind::MissingReturnTypeMagicMethod(name.to_string()),
+                            let mut check = Check::new(
+                                CheckKind::MissingReturnTypeSpecialMethod(name.to_string()),
                                 Range::from_located(stmt),
-                            ));
+                            );
+                            if checker.patch(check.kind.code()) {
+                                match fixes::add_return_none_annotation(checker.locator, stmt) {
+                                    Ok(fix) => check.amend(fix),
+                                    Err(e) => error!("Failed to generate fix: {e}"),
+                                }
+                            }
+                            checker.add_check(check);
                         }
                     }
+                } else if visibility::is_magic(stmt) {
+                    if checker.settings.enabled.contains(&CheckCode::ANN204) {
+                        checker.add_check(Check::new(
+                            CheckKind::MissingReturnTypeSpecialMethod(name.to_string()),
+                            Range::from_located(stmt),
+                        ));
+                    }
                 } else {
                     match visibility {
                         Visibility::Public => {

src/flake8_annotations/settings.rs

@@ -1,51 +1,53 @@
 //! Settings for the `flake-annotations` plugin.
 
 use ruff_macros::ConfigurationOptions;
+use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 
-#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Default, ConfigurationOptions)]
-#[serde(deny_unknown_fields, rename_all = "kebab-case")]
+#[derive(
+    Debug, PartialEq, Eq, Serialize, Deserialize, Default, ConfigurationOptions, JsonSchema,
+)]
+#[serde(
+    deny_unknown_fields,
+    rename_all = "kebab-case",
+    rename = "Flake8AnnotationsOptions"
+)]
 pub struct Options {
     #[option(
-        doc = r#"
-            Whether to allow the omission of a return type hint for `__init__` if at least one
-            argument is annotated.
-        "#,
         default = "false",
         value_type = "bool",
         example = "mypy-init-return = true"
     )]
+    /// Whether to allow the omission of a return type hint for `__init__` if at
+    /// least one argument is annotated.
     pub mypy_init_return: Option<bool>,
     #[option(
-        doc = r#"
-            Whether to suppress `ANN000`-level errors for arguments matching the "dummy" variable
-            regex (like `_`).
-        "#,
         default = "false",
         value_type = "bool",
         example = "suppress-dummy-args = true"
     )]
+    /// Whether to suppress `ANN000`-level errors for arguments matching the
+    /// "dummy" variable regex (like `_`).
     pub suppress_dummy_args: Option<bool>,
     #[option(
-        doc = r#"
-            Whether to suppress `ANN200`-level errors for functions that meet either of the
-            following criteria:
-
-            - Contain no `return` statement.
-            - Explicit `return` statement(s) all return `None` (explicitly or implicitly).
-        "#,
         default = "false",
         value_type = "bool",
         example = "suppress-none-returning = true"
     )]
+    /// Whether to suppress `ANN200`-level errors for functions that meet either
+    /// of the following criteria:
+    ///
+    /// - Contain no `return` statement.
+    /// - Explicit `return` statement(s) all return `None` (explicitly or
+    ///   implicitly).
     pub suppress_none_returning: Option<bool>,
     #[option(
-        doc = "Whether to suppress `ANN401` for dynamically typed `*args` and `**kwargs` \
-               arguments.",
         default = "false",
         value_type = "bool",
         example = "allow-star-arg-any = true"
     )]
+    /// Whether to suppress `ANN401` for dynamically typed `*args` and
+    /// `**kwargs` arguments.
     pub allow_star_arg_any: Option<bool>,
 }
 

src/flake8_annotations/snapshots/ruff__flake8_annotations__tests__mypy_init_return.snap

@@ -3,23 +3,37 @@ source: src/flake8_annotations/mod.rs
 expression: checks
 ---
 - kind:
-    MissingReturnTypeMagicMethod: __init__
+    MissingReturnTypeSpecialMethod: __init__
   location:
     row: 5
     column: 4
   end_location:
     row: 6
     column: 11
-  fix: ~
+  fix:
+    content: " -> None"
+    location:
+      row: 5
+      column: 22
+    end_location:
+      row: 5
+      column: 22
 - kind:
-    MissingReturnTypeMagicMethod: __init__
+    MissingReturnTypeSpecialMethod: __init__
   location:
     row: 11
     column: 4
   end_location:
     row: 12
     column: 11
-  fix: ~
+  fix:
+    content: " -> None"
+    location:
+      row: 11
+      column: 27
+    end_location:
+      row: 11
+      column: 27
 - kind:
     MissingReturnTypePrivateFunction: __init__
   location:

src/flake8_bandit/mod.rs

@@ -26,7 +26,6 @@ mod tests {
                 .join(path)
                 .as_path(),
             &settings::Settings::for_rule(check_code),
-            true,
         )?;
         checks.sort_by_key(|check| check.location);
         insta::assert_yaml_snapshot!(snapshot, checks);