Bump version to 0.0.183

Avoid removing partially-unused imports (#1259 )
Remove extraneous test file
2022-12-15 23:15:12 -05:00 · 2022-12-15 23:13:58 -05:00 · 2022-12-15 23:12:19 -05:00 · 2022-12-15 23:10:59 -05:00 · 2022-12-15 22:17:31 -05:00 · 2022-12-15 15:26:41 -05:00
139 changed files with 5883 additions and 1466 deletions
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -115,7 +115,9 @@ 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"
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -1,6 +1,6 @@
 repos:
  - repo: https://github.com/charliermarsh/ruff-pre-commit
-    rev: v0.0.177
+    rev: v0.0.183
    hooks:
      - id: ruff

--- a/BREAKING_CHANGES.md
+++ b/BREAKING_CHANGES.md
@@ -0,0 +1,23 @@
+# Breaking Changes
+
+## 0.0.181
+
+### Files excluded by `.gitignore` are now ignored ([#1234](https://github.com/charliermarsh/ruff/pull/1234))
+
+Ruff will now avoid checking files that are excluded by `.ignore`, `.gitignore`,
+`.git/info/exclude`, and global `gitignore` files. This behavior is powered by the [`ignore`](https://docs.rs/ignore/latest/ignore/struct.WalkBuilder.html#ignore-rules)
+crate, and is applied in addition to Ruff's built-in `exclude` system.
+
+To disable this behavior, set `respect-gitignore = false` in your `pyproject.toml` file.
+
+Note that hidden files (i.e., files and directories prefixed with a `.`) are _not_ ignored by
+default.
+
+## 0.0.178
+
+### Configuration files are now resolved hierarchically ([#1190](https://github.com/charliermarsh/ruff/pull/1190))
+
+`pyproject.toml` files are now resolved hierarchically, such that for each Python file, we find
+the first `pyproject.toml` file in its path, and use that to determine its lint settings.
+
+See the [README](https://github.com/charliermarsh/ruff#pyprojecttoml-discovery) for more.
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -724,7 +724,7 @@ checksum = "0ce7134b9999ecaf8bcd65542e436736ef32ddca1b3e06094cb6ec5755203b80"

 [[package]]
 name = "flake8-to-ruff"
-version = "0.0.177-dev.0"
+version = "0.0.183-dev.0"
 dependencies = [
 "anyhow",
 "clap 4.0.29",
@@ -796,6 +796,12 @@ dependencies = [
 "wasm-bindgen",
 ]

+[[package]]
+name = "glob"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9b919933a397b79c37e33b77bb2aa3dc8eb6e165ad809e58ff75bc7db2e34574"
+
 [[package]]
 name = "globset"
 version = "0.4.9"
@@ -888,6 +894,24 @@ dependencies = [
 "unicode-normalization",
 ]

+[[package]]
+name = "ignore"
+version = "0.4.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "713f1b139373f96a2e0ce3ac931cd01ee973c3c5dd7c40c0c2efe96ad2b6751d"
+dependencies = [
+ "crossbeam-utils",
+ "globset",
+ "lazy_static",
+ "log",
+ "memchr",
+ "regex",
+ "same-file",
+ "thread_local",
+ "walkdir",
+ "winapi-util",
+]
+
 [[package]]
 name = "indexmap"
 version = "1.9.2"
@@ -1821,7 +1845,7 @@ dependencies = [

 [[package]]
 name = "ruff"
-version = "0.0.177"
+version = "0.0.183"
 dependencies = [
 "annotate-snippets 0.9.1",
 "anyhow",
@@ -1841,7 +1865,9 @@ dependencies = [
 "fern",
 "filetime",
 "getrandom 0.2.8",
+ "glob",
 "globset",
+ "ignore",
 "insta",
 "itertools",
 "libcst",
@@ -1869,12 +1895,13 @@ dependencies = [
 "titlecase",
 "toml",
 "update-informer",
+ "ureq",
 "walkdir",
 ]

 [[package]]
 name = "ruff_dev"
-version = "0.0.177"
+version = "0.0.183"
 dependencies = [
 "anyhow",
 "clap 4.0.29",
@@ -1892,7 +1919,7 @@ dependencies = [

 [[package]]
 name = "ruff_macros"
-version = "0.0.177"
+version = "0.0.183"
 dependencies = [
 "proc-macro2",
 "quote",
@@ -1935,7 +1962,7 @@ dependencies = [
 [[package]]
 name = "rustpython-ast"
 version = "0.1.0"
-source = "git+https://github.com/RustPython/RustPython.git?rev=2edd0d264c50c7807bcff03a52a6509e8b7f187f#2edd0d264c50c7807bcff03a52a6509e8b7f187f"
+source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
 dependencies = [
 "num-bigint",
 "rustpython-common",
@@ -1945,7 +1972,7 @@ dependencies = [
 [[package]]
 name = "rustpython-common"
 version = "0.0.0"
-source = "git+https://github.com/RustPython/RustPython.git?rev=2edd0d264c50c7807bcff03a52a6509e8b7f187f#2edd0d264c50c7807bcff03a52a6509e8b7f187f"
+source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
 dependencies = [
 "ascii",
 "cfg-if 1.0.0",
@@ -1968,7 +1995,7 @@ dependencies = [
 [[package]]
 name = "rustpython-compiler-core"
 version = "0.1.2"
-source = "git+https://github.com/RustPython/RustPython.git?rev=2edd0d264c50c7807bcff03a52a6509e8b7f187f#2edd0d264c50c7807bcff03a52a6509e8b7f187f"
+source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
 dependencies = [
 "bincode",
 "bitflags",
@@ -1985,7 +2012,7 @@ dependencies = [
 [[package]]
 name = "rustpython-parser"
 version = "0.1.2"
-source = "git+https://github.com/RustPython/RustPython.git?rev=2edd0d264c50c7807bcff03a52a6509e8b7f187f#2edd0d264c50c7807bcff03a52a6509e8b7f187f"
+source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
 dependencies = [
 "ahash",
 "anyhow",
@@ -2297,6 +2324,15 @@ dependencies = [
 "syn",
 ]

+[[package]]
+name = "thread_local"
+version = "1.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5516c27b78311c50bf42c071425c560ac799b11c30b31f87e3081965fe5e0180"
+dependencies = [
+ "once_cell",
+]
+
 [[package]]
 name = "time"
 version = "0.1.45"
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,7 +6,7 @@ members = [

 [package]
 name = "ruff"
-version = "0.0.177"
+version = "0.0.183"
 edition = "2021"
 rust-version = "1.65.0"

@@ -28,7 +28,9 @@ common-path = { version = "1.0.0" }
 dirs = { version = "4.0.0" }
 fern = { version = "0.6.1" }
 filetime = { version = "0.2.17" }
+glob = { version = "0.3.0" }
 globset = { version = "0.4.9" }
+ignore = { version = "0.4.18" }
 itertools = { version = "0.10.5" }
 libcst = { git = "https://github.com/charliermarsh/LibCST", rev = "f2f0b7a487a8725d161fe8b3ed73a6758b21e177" }
 log = { version = "0.4.17" }
@@ -41,11 +43,11 @@ 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 = "0.0.177", path = "ruff_macros" }
+ruff_macros = { version = "0.0.183", path = "ruff_macros" }
 rustc-hash = { version = "1.1.0" }
-rustpython-ast = { features = ["unparse"], git = "https://github.com/RustPython/RustPython.git", rev = "2edd0d264c50c7807bcff03a52a6509e8b7f187f" }
-rustpython-common = { git = "https://github.com/RustPython/RustPython.git", rev = "2edd0d264c50c7807bcff03a52a6509e8b7f187f" }
-rustpython-parser = { features = ["lalrpop"], git = "https://github.com/RustPython/RustPython.git", rev = "2edd0d264c50c7807bcff03a52a6509e8b7f187f" }
+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" }
 serde = { version = "1.0.147", features = ["derive"] }
 serde_json = { version = "1.0.87" }
 strum = { version = "0.24.1", features = ["strum_macros"] }
@@ -69,6 +71,7 @@ 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"]
--- a/README.md
+++ b/README.md
@@ -86,6 +86,7 @@ of [Conda](https://docs.conda.io/en/latest/):
   1. [flake8-builtins (A)](#flake8-builtins-a)
   1. [flake8-comprehensions (C4)](#flake8-comprehensions-c4)
   1. [flake8-debugger (T10)](#flake8-debugger-t10)
+   1. [flake8-errmsg (EM)](#flake8-errmsg-em)
   1. [flake8-import-conventions (ICN)](#flake8-import-conventions-icn)
   1. [flake8-print (T20)](#flake8-print-t20)
   1. [flake8-quotes (Q)](#flake8-quotes-q)
@@ -94,6 +95,7 @@ of [Conda](https://docs.conda.io/en/latest/):
   1. [flake8-tidy-imports (TID)](#flake8-tidy-imports-tid)
   1. [flake8-unused-arguments (ARG)](#flake8-unused-arguments-arg)
   1. [eradicate (ERA)](#eradicate-era)
+   1. [pandas-vet (PDV)](#pandas-vet-pdv)
   1. [pygrep-hooks (PGH)](#pygrep-hooks-pgh)
   1. [Pylint (PLC, PLE, PLR, PLW)](#pylint-plc-ple-plr-plw)
   1. [Ruff-specific rules (RUF)](#ruff-specific-rules-ruf)<!-- End auto-generated table of contents. -->
@@ -155,7 +157,7 @@ Ruff also works with [pre-commit](https://pre-commit.com):
 ```yaml
 repos:
  - repo: https://github.com/charliermarsh/ruff-pre-commit
-    rev: v0.0.177
+    rev: v0.0.183
    hooks:
      - id: ruff
 ```
@@ -304,13 +306,15 @@ Options:
      --per-file-ignores <PER_FILE_IGNORES>
          List of mappings from file pattern to code to exclude
      --format <FORMAT>
-          Output serialization format for error messages [default: text] [possible values: text, json, junit, grouped]
+          Output serialization format for error messages [possible values: text, json, junit, grouped, github]
      --show-source
          Show violations with source code
+      --respect-gitignore
+          Respect file exclusions via `.gitignore` and other standard ignore files
      --show-files
          See the files Ruff will be run against with the current settings
      --show-settings
-          See Ruff's settings
+          See the settings Ruff will use to check a given Python file
      --add-noqa
          Enable automatic additions of noqa directives to failing lines
      --dummy-variable-rgx <DUMMY_VARIABLE_RGX>
@@ -331,6 +335,55 @@ Options:
          Print version information
 ```

+### `pyproject.toml` discovery
+
+Similar to [ESLint](https://eslint.org/docs/latest/user-guide/configuring/configuration-files#cascading-and-hierarchy),
+Ruff supports hierarchical configuration, such that the "closest" `pyproject.toml` file in the
+directory hierarchy is used for every individual file, with all paths in the `pyproject.toml` file
+(e.g., `exclude` globs, `src` paths) being resolved relative to the directory containing the
+`pyproject.toml` file.
+
+There are a few exceptions to these rules:
+
+1. In locating the "closest" `pyproject.toml` file for a given path, Ruff ignore any
+   `pyproject.toml` files that lack a `[tool.ruff]` section.
+2. If a configuration file is passed directly via `--config`, those settings are used for across
+   files. Any relative paths in that configuration file (like `exclude` globs or `src` paths) are
+   resolved relative to the _current working directory_.
+3. If no `pyproject.toml` file is found in the filesystem hierarchy, Ruff will fall back to using
+   a default configuration. If a user-specific configuration file exists
+   at `${config_dir}/ruff/pyproject.toml`,
+   that file will be used instead of the default configuration, with `${config_dir}` being
+   determined via the [`dirs](https://docs.rs/dirs/4.0.0/dirs/fn.config_dir.html) crate, and all
+   relative paths being again resolved relative to the _current working directory_.
+4. Any `pyproject.toml`-supported settings that are provided on the command-line (e.g., via
+   `--select`) will override the settings in _every_ resolved configuration file.
+
+Unlike [ESLint](https://eslint.org/docs/latest/user-guide/configuring/configuration-files#cascading-and-hierarchy),
+Ruff does not merge settings across configuration files; instead, the "closest" configuration file
+is used, and any parent configuration files are ignored. In lieu of this implicit cascade, Ruff
+supports an [`extend`](#extend) field, which allows you to inherit the settings from another
+`pyproject.toml` file, like so:
+
+```toml
+# Extend the `pyproject.toml` file in the parent directory.
+extend = "../pyproject.toml"
+# But use a different line length.
+line-length = 100
+```
+
+### Python file discovery
+
+When passed a path on the command-line, Ruff will automatically discover all Python files in that
+path, taking into account the [`exclude`](#exclude) and [`extend-exclude`](#extend-exclude) settings
+in each directory's `pyproject.toml` file.
+
+By default, Ruff will also skip any files that are omitted via `.ignore`, `.gitignore`,
+`.git/info/exclude`, and global `gitignore` files (see: [`respect-gitignore`](#respect-gitignore)).
+
+Files that are passed to `ruff` directly are always checked, regardless of the above criteria.
+For example, `ruff /path/to/excluded/file.py` will always check `file.py`.
+
 ### Ignoring errors

 To omit a lint check entirely, add it to the "ignore" list via [`ignore`](#ignore) or
@@ -566,6 +619,7 @@ For more, see [pyupgrade](https://pypi.org/project/pyupgrade/3.2.0/) on PyPI.
 | UP013 | ConvertTypedDictFunctionalToClass | Convert `...` from `TypedDict` functional to class syntax | 🛠 |
 | UP014 | ConvertNamedTupleFunctionalToClass | Convert `...` from `NamedTuple` functional to class syntax | 🛠 |
 | UP015 | RedundantOpenModes | Unnecessary open mode parameters | 🛠 |
+| UP016 | RemoveSixCompat | Unnecessary `six` compatibility usage | 🛠 |

 ### pep8-naming (N)

@@ -731,6 +785,16 @@ For more, see [flake8-debugger](https://pypi.org/project/flake8-debugger/4.1.2/)
 | ---- | ---- | ------- | --- |
 | T100 | Debugger | Import for `...` found |  |

+### flake8-errmsg (EM)
+
+For more, see [flake8-errmsg](https://pypi.org/project/flake8-errmsg/0.4.0/) on PyPI.
+
+| Code | Name | Message | Fix |
+| ---- | ---- | ------- | --- |
+| EM101 | RawStringInException | Exception must not use a string literal, assign to variable first |  |
+| EM102 | FStringInException | Exception must not use an f-string literal, assign to variable first |  |
+| EM103 | DotFormatInException | Exception must not use a `.format()` string directly, assign to variable first |  |
+
 ### flake8-import-conventions (ICN)

 | Code | Name | Message | Fix |
@@ -808,6 +872,25 @@ For more, see [eradicate](https://pypi.org/project/eradicate/2.1.0/) on PyPI.
 | ---- | ---- | ------- | --- |
 | ERA001 | CommentedOutCode | Found commented-out code | 🛠 |

+### pandas-vet (PDV)
+
+For more, see [pandas-vet](https://pypi.org/project/pandas-vet/0.2.3/) on PyPI.
+
+| Code | Name | Message | Fix |
+| ---- | ---- | ------- | --- |
+| PDV002 | UseOfInplaceArgument | `inplace=True` should be avoided; it has inconsistent behavior |  |
+| PDV003 | UseOfDotIsNull | `.isna` is preferred to `.isnull`; functionality is equivalent |  |
+| PDV004 | UseOfDotNotNull | `.notna` is preferred to `.notnull`; functionality is equivalent |  |
+| PDV007 | UseOfDotIx | ``ix` i` deprecated; use more explicit `.loc` o` `.iloc` |  |
+| PDV008 | UseOfDotAt | Use `.loc` instead of `.at`.  If speed is important, use numpy. |  |
+| PDV009 | UseOfDotIat | Use `.iloc` instea` of `.iat`.  If speed is important, use numpy. |  |
+| PDV010 | UseOfDotPivotOrUnstack | `.pivot_table` is preferred to `.pivot` or `.unstack`; provides same functionality |  |
+| PDV011 | UseOfDotValues | Use `.to_numpy()` instead of `.values` |  |
+| PDV012 | UseOfDotReadTable | `.read_csv` is preferred to `.read_table`; provides same functionality |  |
+| PDV013 | UseOfDotStack | `.melt` is preferred to `.stack`; provides same functionality |  |
+| PDV015 | UseOfPdMerge | Use `.merge` method instead of `pd.merge` function. They have equivalent functionality. |  |
+| PDV901 | DfIsABadVariableName | `df` is a bad variable name. Be kinder to your future self. |  |
+
 ### pygrep-hooks (PGH)

 For more, see [pygrep-hooks](https://github.com/pre-commit/pygrep-hooks) on GitHub.
@@ -1039,8 +1122,7 @@ conflicts with the `isort` rules, like `I001`).

 Beyond the rule set, Ruff suffers from the following limitations vis-à-vis Flake8:

-1. Ruff does not yet support a few Python 3.9 and 3.10 language features, including structural
-   pattern matching and parenthesized context managers.
+1. Ruff does not yet support structural pattern matching.
 2. Flake8 has a plugin architecture and supports writing custom lint rules. (Instead, popular Flake8
   plugins are re-implemented in Rust as part of Ruff itself.)

@@ -1422,7 +1504,7 @@ Exclusions are based on globs, and can be either:
  (to exclude any Python files in `directory`). Note that these paths are relative to the
  project root (e.g., the directory containing your `pyproject.toml`).

-Note that you'll typically want to use [`extend_exclude`](#extend_exclude) to modify
+Note that you'll typically want to use [`extend-exclude`](#extend-exclude) to modify
 the excluded paths.

 **Default value**: `[".bzr", ".direnv", ".eggs", ".git", ".hg", ".mypy_cache", ".nox", ".pants.d", ".ruff_cache", ".svn", ".tox", ".venv", "__pypackages__", "_build", "buck-out", "build", "dist", "node_modules", "venv"]`
@@ -1438,6 +1520,30 @@ exclude = [".venv"]

 ---

+#### [`extend`](#extend)
+
+A path to a local `pyproject.toml` file to merge into this configuration.
+
+To resolve the current `pyproject.toml` file, Ruff will first resolve this base
+configuration file, then merge in any properties defined in the current configuration
+file.
+
+**Default value**: `None`
+
+**Type**: `Path`
+
+**Example usage**:
+
+```toml
+[tool.ruff]
+# Extend the `pyproject.toml` file in the parent directory.
+extend = "../pyproject.toml"
+# But use a different line length.
+line-length = 100
+```
+
+---
+
 #### [`extend-exclude`](#extend-exclude)

 A list of file patterns to omit from linting, in addition to those specified by `exclude`.
@@ -1650,6 +1756,24 @@ any matching files.

 ---

+#### [`respect-gitignore`](#respect-gitignore)
+
+Whether to automatically exclude files that are ignored by `.ignore`, `.gitignore`,
+`.git/info/exclude`, and global `gitignore` files. Enabled by default.
+
+**Default value**: `true`
+
+**Type**: `bool`
+
+**Example usage**:
+
+```toml
+[tool.ruff]
+respect_gitignore = false
+```
+
+---
+
 #### [`select`](#select)

 A list of check code prefixes to enable. Prefixes can specify exact checks (like
@@ -1695,6 +1819,25 @@ show-source = true

 The source code paths to consider, e.g., when resolving first- vs. third-party imports.

+As an example: given a Python package structure like:
+
+```text
+my_package/
+  pyproject.toml
+  src/
+    my_package/
+      __init__.py
+      foo.py
+      bar.py
+```
+
+The `src` directory should be included in `source` (e.g., `source = ["src"]`), such that
+when resolving imports, `my_package.foo` is considered a first-party import.
+
+This field supports globs. For example, if you have a series of Python packages in
+a `python_modules` directory, `src = ["python_modules/*"]` would expand to incorporate
+all of the packages in that directory.
+
 **Default value**: `["."]`

 **Type**: `Vec<PathBuf>`
@@ -1844,6 +1987,25 @@ extend-immutable-calls = ["fastapi.Depends", "fastapi.Query"]

 ---

+### `flake8-errmsg`
+
+#### [`max-string-length`](#max-string-length)
+
+Maximum string length for string literals in exception messages.
+
+**Default value**: `0`
+
+**Type**: `usize`
+
+**Example usage**:
+
+```toml
+[tool.ruff.flake8-errmsg]
+max-string-length = 20
+```
+
+---
+
 ### `flake8-import-conventions`

 #### [`aliases`](#aliases)
--- a/flake8_to_ruff/Cargo.lock
+++ b/flake8_to_ruff/Cargo.lock
@@ -771,7 +771,7 @@ checksum = "0ce7134b9999ecaf8bcd65542e436736ef32ddca1b3e06094cb6ec5755203b80"

 [[package]]
 name = "flake8_to_ruff"
-version = "0.0.177"
+version = "0.0.183"
 dependencies = [
 "anyhow",
 "clap",
@@ -1975,7 +1975,7 @@ dependencies = [

 [[package]]
 name = "ruff"
-version = "0.0.177"
+version = "0.0.183"
 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=2edd0d264c50c7807bcff03a52a6509e8b7f187f#2edd0d264c50c7807bcff03a52a6509e8b7f187f"
+source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
 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=2edd0d264c50c7807bcff03a52a6509e8b7f187f#2edd0d264c50c7807bcff03a52a6509e8b7f187f"
+source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
 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=2edd0d264c50c7807bcff03a52a6509e8b7f187f#2edd0d264c50c7807bcff03a52a6509e8b7f187f"
+source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
 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=2edd0d264c50c7807bcff03a52a6509e8b7f187f#2edd0d264c50c7807bcff03a52a6509e8b7f187f"
+source = "git+https://github.com/RustPython/RustPython.git?rev=8d879a53197f9c73062f6160410bdba796a71cbf#8d879a53197f9c73062f6160410bdba796a71cbf"
 dependencies = [
 "ahash",
 "anyhow",
--- a/flake8_to_ruff/Cargo.toml
+++ b/flake8_to_ruff/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "flake8-to-ruff"
-version = "0.0.177-dev.0"
+version = "0.0.183-dev.0"
 edition = "2021"

 [lib]
--- a/flake8_to_ruff/src/converter.rs
+++ b/flake8_to_ruff/src/converter.rs
@@ -7,7 +7,8 @@ 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::plugin::Plugin;
@@ -73,6 +74,7 @@ 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 +196,15 @@ 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 +220,9 @@ 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);
    }
@@ -246,6 +260,7 @@ mod tests {
            allowed_confusables: None,
            dummy_variable_rgx: None,
            exclude: None,
+            extend: None,
            extend_exclude: None,
            extend_ignore: None,
            extend_select: None,
@@ -257,6 +272,7 @@ mod tests {
            ignore_init_module_imports: None,
            line_length: None,
            per_file_ignores: None,
+            respect_gitignore: None,
            select: Some(vec![
                CheckCodePrefix::E,
                CheckCodePrefix::F,
@@ -268,6 +284,7 @@ mod tests {
            unfixable: None,
            flake8_annotations: None,
            flake8_bugbear: None,
+            flake8_errmsg: None,
            flake8_quotes: None,
            flake8_tidy_imports: None,
            flake8_import_conventions: None,
@@ -291,6 +308,7 @@ mod tests {
            allowed_confusables: None,
            dummy_variable_rgx: None,
            exclude: None,
+            extend: None,
            extend_exclude: None,
            extend_ignore: None,
            extend_select: None,
@@ -302,6 +320,7 @@ mod tests {
            ignore_init_module_imports: None,
            line_length: Some(100),
            per_file_ignores: None,
+            respect_gitignore: None,
            select: Some(vec![
                CheckCodePrefix::E,
                CheckCodePrefix::F,
@@ -313,6 +332,7 @@ mod tests {
            unfixable: None,
            flake8_annotations: None,
            flake8_bugbear: None,
+            flake8_errmsg: None,
            flake8_quotes: None,
            flake8_tidy_imports: None,
            flake8_import_conventions: None,
@@ -336,6 +356,7 @@ mod tests {
            allowed_confusables: None,
            dummy_variable_rgx: None,
            exclude: None,
+            extend: None,
            extend_exclude: None,
            extend_ignore: None,
            extend_select: None,
@@ -347,6 +368,7 @@ mod tests {
            ignore_init_module_imports: None,
            line_length: Some(100),
            per_file_ignores: None,
+            respect_gitignore: None,
            select: Some(vec![
                CheckCodePrefix::E,
                CheckCodePrefix::F,
@@ -358,6 +380,7 @@ mod tests {
            unfixable: None,
            flake8_annotations: None,
            flake8_bugbear: None,
+            flake8_errmsg: None,
            flake8_quotes: None,
            flake8_tidy_imports: None,
            flake8_import_conventions: None,
@@ -381,6 +404,7 @@ mod tests {
            allowed_confusables: None,
            dummy_variable_rgx: None,
            exclude: None,
+            extend: None,
            extend_exclude: None,
            extend_ignore: None,
            extend_select: None,
@@ -392,6 +416,7 @@ mod tests {
            ignore_init_module_imports: None,
            line_length: None,
            per_file_ignores: None,
+            respect_gitignore: None,
            select: Some(vec![
                CheckCodePrefix::E,
                CheckCodePrefix::F,
@@ -403,6 +428,7 @@ mod tests {
            unfixable: None,
            flake8_annotations: None,
            flake8_bugbear: None,
+            flake8_errmsg: None,
            flake8_quotes: None,
            flake8_tidy_imports: None,
            flake8_import_conventions: None,
@@ -426,6 +452,7 @@ mod tests {
            allowed_confusables: None,
            dummy_variable_rgx: None,
            exclude: None,
+            extend: None,
            extend_exclude: None,
            extend_ignore: None,
            extend_select: None,
@@ -437,6 +464,7 @@ mod tests {
            ignore_init_module_imports: None,
            line_length: None,
            per_file_ignores: None,
+            respect_gitignore: None,
            select: Some(vec![
                CheckCodePrefix::E,
                CheckCodePrefix::F,
@@ -448,6 +476,7 @@ mod tests {
            unfixable: 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,
@@ -479,6 +508,7 @@ mod tests {
            allowed_confusables: None,
            dummy_variable_rgx: None,
            exclude: None,
+            extend: None,
            extend_exclude: None,
            extend_ignore: None,
            extend_select: None,
@@ -490,6 +520,7 @@ mod tests {
            ignore_init_module_imports: None,
            line_length: None,
            per_file_ignores: None,
+            respect_gitignore: None,
            select: Some(vec![
                CheckCodePrefix::D100,
                CheckCodePrefix::D101,
@@ -537,6 +568,7 @@ mod tests {
            unfixable: None,
            flake8_annotations: None,
            flake8_bugbear: None,
+            flake8_errmsg: None,
            flake8_quotes: None,
            flake8_tidy_imports: None,
            flake8_import_conventions: None,
@@ -560,6 +592,7 @@ mod tests {
            allowed_confusables: None,
            dummy_variable_rgx: None,
            exclude: None,
+            extend: None,
            extend_exclude: None,
            extend_ignore: None,
            extend_select: None,
@@ -571,6 +604,7 @@ mod tests {
            ignore_init_module_imports: None,
            line_length: None,
            per_file_ignores: None,
+            respect_gitignore: None,
            select: Some(vec![
                CheckCodePrefix::E,
                CheckCodePrefix::F,
@@ -583,6 +617,7 @@ mod tests {
            unfixable: 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,
--- a/flake8_to_ruff/src/plugin.rs
+++ b/flake8_to_ruff/src/plugin.rs
@@ -14,6 +14,7 @@ pub enum Plugin {
    Flake8Comprehensions,
    Flake8Debugger,
    Flake8Docstrings,
+    Flake8ErrMsg,
    Flake8Eradicate,
    Flake8Print,
    Flake8Quotes,
@@ -21,6 +22,7 @@ pub enum Plugin {
    Flake8Simplify,
    Flake8TidyImports,
    McCabe,
+    PandasVet,
    PEP8Naming,
    Pyupgrade,
 }
@@ -39,12 +41,14 @@ impl FromStr for Plugin {
            "flake8-debugger" => Ok(Plugin::Flake8Debugger),
            "flake8-docstrings" => Ok(Plugin::Flake8Docstrings),
            "flake8-eradicate" => Ok(Plugin::Flake8BlindExcept),
+            "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}")),
@@ -57,19 +61,24 @@ impl Plugin {
        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::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::McCabe => CheckCodePrefix::C9,
+            // TODO(charlie): Handle rename of `PD` to `PDV`.
+            Plugin::PandasVet => CheckCodePrefix::PDV,
            Plugin::PEP8Naming => CheckCodePrefix::N,
            Plugin::Pyupgrade => CheckCodePrefix::U,
        }
@@ -101,14 +110,16 @@ 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::PDV],
            Plugin::PEP8Naming => vec![CheckCodePrefix::N],
-            Plugin::Pyupgrade => vec![CheckCodePrefix::U],
+            Plugin::Pyupgrade => vec![CheckCodePrefix::UP],
        }
    }
 }
@@ -377,6 +388,9 @@ 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);
+            }
            _ => {}
        }
    }
@@ -398,11 +412,13 @@ pub fn infer_plugins_from_codes(codes: &BTreeSet<CheckCodePrefix>) -> Vec<Plugin
        Plugin::Flake8Debugger,
        Plugin::Flake8Docstrings,
        Plugin::Flake8Eradicate,
+        Plugin::Flake8ErrMsg,
        Plugin::Flake8Print,
        Plugin::Flake8Quotes,
        Plugin::Flake8Return,
        Plugin::Flake8Simplify,
        Plugin::Flake8TidyImports,
+        Plugin::PandasVet,
        Plugin::PEP8Naming,
        Plugin::Pyupgrade,
    ]
--- a/resources/test/fixtures/README.md
+++ b/resources/test/fixtures/README.md
@@ -0,0 +1,3 @@
+# fixtures
+
+Fixture files used for snapshot testing.
--- a/resources/test/fixtures/flake8_bugbear/B009_B010.py
+++ b/resources/test/fixtures/flake8_bugbear/B009_B010.py
@@ -20,6 +20,8 @@ getattr(foo, "_123abc")
 getattr(foo, "abc123")
 getattr(foo, r"abc123")
 _ = lambda x: getattr(x, "bar")
+if getattr(x, "bar"):
+    pass

 # Valid setattr usage
 setattr(foo, bar, None)
@@ -28,6 +30,8 @@ setattr(foo, "123abc", None)
 setattr(foo, r"123\abc", None)
 setattr(foo, "except", None)
 _ = lambda x: setattr(x, "bar", 1)
+if setattr(x, "bar", 1):
+    pass

 # Invalid usage
 setattr(foo, "bar", None)
--- a/resources/test/fixtures/flake8_errmsg/EM.py
+++ b/resources/test/fixtures/flake8_errmsg/EM.py
@@ -0,0 +1,19 @@
+from __future__ import annotations
+
+
+def f_a():
+    raise RuntimeError("This is an example exception")
+
+
+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)
--- a/resources/test/fixtures/isort/leading_prefix.py
+++ b/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
--- a/resources/test/fixtures/pycodestyle/constant_literals.py
+++ b/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
--- a/resources/test/fixtures/pyflakes/F401_7.py
+++ b/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,
+)
--- a/resources/test/fixtures/pyflakes/F811_20.py
+++ b/resources/test/fixtures/pyflakes/F811_20.py
@@ -7,7 +7,6 @@ import fu


 class bar:
-    # STOPSHIP: This errors.
    fu = 1


--- a/resources/test/fixtures/pyflakes/F841_0.py
+++ b/resources/test/fixtures/pyflakes/F841_0.py
@@ -10,13 +10,13 @@ except ValueError as e:
    print(e)


-def f1():
+def f():
    x = 1
    y = 2
    z = x + y


-def f2():
+def f():
    foo = (1, 2)
    (a, b) = (1, 2)

@@ -26,12 +26,12 @@ def f2():
    (x, y) = baz = bar


-def f3():
+def f():
    locals()
    x = 1


-def f4():
+def f():
    _ = 1
    __ = 1
    _discarded = 1
@@ -40,26 +40,26 @@ def f4():
 a = 1


-def f5():
+def f():
    global a

-    # Used in `f7` via `nonlocal`.
+    # Used in `c` via `nonlocal`.
    b = 1

-    def f6():
+    def c():
        # F841
        b = 1

-    def f7():
+    def d():
        nonlocal b


-def f6():
+def f():
    annotations = []
    assert len([annotations for annotations in annotations])


-def f7():
+def f():
    def connect():
        return None, None

@@ -67,6 +67,22 @@ def f7():
        cursor.execute("SELECT * FROM users")


-def f8():
-    with open("file") as f, open("") as ((a, b)):
+def f():
+    def connect():
+        return None, None
+
+    with (connect() as (connection, cursor)):
+        cursor.execute("SELECT * FROM users")
+
+
+def f():
+    with open("file") as my_file, open("") as ((this, that)):
+        print("hello")
+
+
+def f():
+    with (
+        open("file") as my_file,
+        open("") as ((this, that)),
+    ):
        print("hello")
--- a/resources/test/fixtures/pyflakes/multi_statement_lines.py
+++ b/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
--- a/resources/test/fixtures/pyproject.toml
+++ b/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"

--- a/resources/test/fixtures/pyupgrade/UP016.py
+++ b/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
--- a/resources/test/project/.gitignore
+++ b/resources/test/project/.gitignore
@@ -0,0 +1 @@
+examples/generated
--- a/resources/test/project/README.md
+++ b/resources/test/project/README.md
@@ -0,0 +1,89 @@
+# project
+
+An example multi-package Python project used to test setting resolution and other complex
+behaviors.
+
+## Expected behavior
+
+Running from the repo root should pick up and enforce the appropriate settings for each package:
+
+```
+∴ 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
+6 potentially fixable with the --fix option.
+```
+
+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
+6 potentially fixable with the --fix option.
+```
+
+Running from the sub-package directory should exhibit the same behavior, but omit the top-level
+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
+1 potentially fixable with the --fix option.
+```
+
+`--config` should force Ruff to use the specified `pyproject.toml` for all files, and resolve
+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
+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:1:8: F401 `os` imported but unused
+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.
+```
+
+Running from a parent directory should this "ignore" the `exclude` (hence, `concepts/file.py` gets
+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
+1 potentially fixable with the --fix option.
+```
+
+Passing an excluded directory directly should report errors in the contained files:
+
+```
+∴ 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
+1 potentially fixable with the --fix option.
+```
--- a/resources/test/project/examples/.dotfiles/pyproject.toml
+++ b/resources/test/project/examples/.dotfiles/pyproject.toml
--- a/resources/test/project/examples/.dotfiles/script.py
+++ b/resources/test/project/examples/.dotfiles/script.py
@@ -0,0 +1,2 @@
+import numpy as np
+from app import app_file
--- a/resources/test/project/examples/docs/docs/init.py
+++ b/resources/test/project/examples/docs/docs/init.py
--- a/resources/test/project/examples/docs/docs/concepts/init.py
+++ b/resources/test/project/examples/docs/docs/concepts/init.py
--- a/resources/test/project/examples/docs/docs/concepts/file.py
+++ b/resources/test/project/examples/docs/docs/concepts/file.py
@@ -0,0 +1,5 @@
+import os
+
+
+def f():
+    x = 1
--- a/resources/test/project/examples/docs/docs/file.py
+++ b/resources/test/project/examples/docs/docs/file.py
@@ -0,0 +1,8 @@
+import os
+
+import numpy as np
+from docs.concepts import file
+
+
+def f():
+    x = 1
--- a/resources/test/project/examples/docs/pyproject.toml
+++ b/resources/test/project/examples/docs/pyproject.toml
@@ -0,0 +1,7 @@
+[tool.ruff]
+extend = "../../pyproject.toml"
+src = ["."]
+# Enable I001, and re-enable F841, to test extension priority.
+extend-select = ["I001", "F841"]
+extend-ignore = ["F401"]
+extend-exclude = ["./docs/concepts/file.py"]
--- a/resources/test/project/examples/excluded/script.py
+++ b/resources/test/project/examples/excluded/script.py
@@ -0,0 +1,5 @@
+import os
+
+
+def f():
+    x = 1
--- a/resources/test/project/pyproject.toml
+++ b/resources/test/project/pyproject.toml
@@ -0,0 +1,5 @@
+[tool.ruff]
+src = [".", "python_modules/*"]
+exclude = ["examples/excluded"]
+extend-select = ["I001"]
+extend-ignore = ["F841"]
--- a/resources/test/project/python_modules/app/app/init.py
+++ b/resources/test/project/python_modules/app/app/init.py
--- a/resources/test/project/python_modules/app/app/app_file.py
+++ b/resources/test/project/python_modules/app/app/app_file.py
--- a/resources/test/project/python_modules/core/core/init.py
+++ b/resources/test/project/python_modules/core/core/init.py
--- a/resources/test/project/python_modules/core/core/core_file.py
+++ b/resources/test/project/python_modules/core/core/core_file.py
--- a/resources/test/project/src/init.py
+++ b/resources/test/project/src/init.py
--- a/resources/test/project/src/file.py
+++ b/resources/test/project/src/file.py
@@ -0,0 +1,5 @@
+import os
+
+
+def f():
+    x = 1
--- a/resources/test/project/src/import_file.py
+++ b/resources/test/project/src/import_file.py
@@ -0,0 +1,7 @@
+import numpy as np
+from app import app_file
+from core import core_file
+
+np.array([1, 2, 3])
+app_file()
+core_file()
--- a/ruff_dev/Cargo.toml
+++ b/ruff_dev/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "ruff_dev"
-version = "0.0.177"
+version = "0.0.183"
 edition = "2021"

 [dependencies]
@@ -11,8 +11,8 @@ 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 = "2edd0d264c50c7807bcff03a52a6509e8b7f187f" }
-rustpython-common = { git = "https://github.com/RustPython/RustPython.git", rev = "2edd0d264c50c7807bcff03a52a6509e8b7f187f" }
-rustpython-parser = { features = ["lalrpop"], git = "https://github.com/RustPython/RustPython.git", rev = "2edd0d264c50c7807bcff03a52a6509e8b7f187f" }
+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" }
 strum = { version = "0.24.1", features = ["strum_macros"] }
 strum_macros = { version = "0.24.3" }
--- a/ruff_macros/Cargo.toml
+++ b/ruff_macros/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "ruff_macros"
-version = "0.0.177"
+version = "0.0.183"
 edition = "2021"

 [lib]
--- a/src/ast/helpers.rs
+++ b/src/ast/helpers.rs
@@ -1,13 +1,26 @@
+use log::error;
 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, Location, Stmt, StmtKind,
 };
+use rustpython_parser::lexer;
+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, .. } => {
@@ -149,15 +162,12 @@ 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;
            }
@@ -166,12 +176,7 @@ 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,
        },
@@ -179,6 +184,32 @@ 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)
+}
+
 /// Extract the names of all handled exceptions.
 pub fn extract_handler_names(handlers: &[Excepthandler]) -> Vec<Vec<&str>> {
    let mut handler_names = vec![];
@@ -229,7 +260,6 @@ 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 {
@@ -311,13 +341,75 @@ pub fn count_trailing_lines(stmt: &Stmt, locator: &SourceCodeLocator) -> usize {
        .count()
 }

+/// Return the appropriate visual `Range` for any message that spans a `Stmt`.
+/// Specifically, this method returns the range of a function or class name,
+/// rather than that of the entire function or class body.
+pub fn identifier_range(stmt: &Stmt, locator: &SourceCodeLocator) -> Range {
+    if matches!(
+        stmt.node,
+        StmtKind::ClassDef { .. }
+            | StmtKind::FunctionDef { .. }
+            | StmtKind::AsyncFunctionDef { .. }
+    ) {
+        let contents = locator.slice_source_code_range(&Range::from_located(stmt));
+        for (start, tok, end) in lexer::make_tokenizer(&contents).flatten() {
+            if matches!(tok, Tok::Name { .. }) {
+                let start = to_absolute(start, stmt.location);
+                let end = to_absolute(end, stmt.location);
+                return Range {
+                    location: start,
+                    end_location: end,
+                };
+            }
+        }
+        error!("Failed to find identifier for {:?}", stmt);
+    }
+    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;
    use rustc_hash::{FxHashMap, FxHashSet};
+    use rustpython_ast::Location;
    use rustpython_parser::parser;

-    use crate::ast::helpers::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;

    #[test]
    fn builtin() -> Result<()> {
@@ -461,4 +553,130 @@ 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();
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            identifier_range(stmt, &locator),
+            Range {
+                location: Location::new(1, 4),
+                end_location: Location::new(1, 5),
+            }
+        );
+
+        let contents = r#"
+def \
+  f():
+  pass
+"#
+        .trim();
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            identifier_range(stmt, &locator),
+            Range {
+                location: Location::new(2, 2),
+                end_location: Location::new(2, 3),
+            }
+        );
+
+        let contents = "class Class(): pass".trim();
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            identifier_range(stmt, &locator),
+            Range {
+                location: Location::new(1, 6),
+                end_location: Location::new(1, 11),
+            }
+        );
+
+        let contents = "class Class: pass".trim();
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            identifier_range(stmt, &locator),
+            Range {
+                location: Location::new(1, 6),
+                end_location: Location::new(1, 11),
+            }
+        );
+
+        let contents = r#"
+@decorator()
+class Class():
+  pass
+"#
+        .trim();
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            identifier_range(stmt, &locator),
+            Range {
+                location: Location::new(2, 6),
+                end_location: Location::new(2, 11),
+            }
+        );
+
+        let contents = r#"x = y + 1"#.trim();
+        let program = parser::parse_program(contents, "<filename>")?;
+        let stmt = program.first().unwrap();
+        let locator = SourceCodeLocator::new(contents);
+        assert_eq!(
+            identifier_range(stmt, &locator),
+            Range {
+                location: Location::new(1, 0),
+                end_location: Location::new(1, 9),
+            }
+        );
+
+        Ok(())
+    }
 }
--- a/src/autofix/fixer.rs
+++ b/src/autofix/fixer.rs
@@ -10,7 +10,7 @@ use crate::autofix::Fix;
 use crate::checks::Check;
 use crate::source_code_locator::SourceCodeLocator;

-#[derive(Hash)]
+#[derive(Debug, Hash)]
 pub enum Mode {
    Generate,
    Apply,
--- a/src/autofix/helpers.rs
+++ b/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)
+        );
    }
 }
--- a/src/autofix/mod.rs
+++ b/src/autofix/mod.rs
@@ -35,12 +35,4 @@ impl Fix {
            end_location: at,
        }
    }
-
-    pub fn dummy(location: Location) -> Self {
-        Self {
-            content: String::new(),
-            location,
-            end_location: location,
-        }
-    }
 }
--- a/src/check_ast.rs
+++ b/src/check_ast.rs
@@ -6,7 +6,7 @@ use itertools::Itertools;
 use log::error;
 use nohash_hasher::IntMap;
 use rustc_hash::{FxHashMap, FxHashSet};
-use rustpython_ast::Location;
+use rustpython_ast::{Located, Location};
 use rustpython_parser::ast::{
    Arg, Arguments, Constant, Excepthandler, ExcepthandlerKind, Expr, ExprContext, ExprKind,
    KeywordData, Operator, Stmt, StmtKind, Suite,
@@ -25,6 +25,7 @@ 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;
@@ -37,9 +38,9 @@ use crate::visibility::{module_visibility, transition_scope, Modifier, Visibilit
 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_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;
@@ -51,7 +52,9 @@ pub struct Checker<'a> {
    // Input data.
    path: &'a Path,
    autofix: bool,
+    ignore_noqa: bool,
    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>,
@@ -98,13 +101,17 @@ pub struct Checker<'a> {
 impl<'a> Checker<'a> {
    pub fn new(
        settings: &'a Settings,
+        noqa_line_for: &'a IntMap<usize, usize>,
        autofix: bool,
+        ignore_noqa: bool,
        path: &'a Path,
        locator: &'a SourceCodeLocator,
    ) -> Checker<'a> {
        Checker {
            settings,
+            noqa_line_for,
            autofix,
+            ignore_noqa,
            path,
            locator,
            checks: vec![],
@@ -199,6 +206,30 @@ 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 self.ignore_noqa {
+            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 +254,10 @@ 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),
                    )
@@ -257,12 +288,11 @@ where
                }

                if self.settings.enabled.contains(&CheckCode::E741) {
-                    let location = Range::from_located(stmt);
                    self.add_checks(
                        names
                            .iter()
                            .filter_map(|name| {
-                                pycodestyle::checks::ambiguous_variable_name(name, location)
+                                pycodestyle::checks::ambiguous_variable_name(name, stmt)
                            })
                            .into_iter(),
                    );
@@ -309,12 +339,11 @@ where
                }

                if self.settings.enabled.contains(&CheckCode::E741) {
-                    let location = Range::from_located(stmt);
                    self.add_checks(
                        names
                            .iter()
                            .filter_map(|name| {
-                                pycodestyle::checks::ambiguous_variable_name(name, location)
+                                pycodestyle::checks::ambiguous_variable_name(name, stmt)
                            })
                            .into_iter(),
                    );
@@ -369,7 +398,8 @@ where
                    if let Some(check) = pep8_naming::checks::invalid_function_name(
                        stmt,
                        name,
-                        &self.settings.pep8_naming,
+                        &self.settings.pep8_naming.ignore_names,
+                        self.locator,
                    ) {
                        self.add_check(check);
                    }
@@ -406,9 +436,12 @@ where
                }

                if self.settings.enabled.contains(&CheckCode::N807) {
-                    if let Some(check) =
-                        pep8_naming::checks::dunder_function_name(self.current_scope(), stmt, name)
-                    {
+                    if let Some(check) = pep8_naming::checks::dunder_function_name(
+                        self.current_scope(),
+                        stmt,
+                        name,
+                        self.locator,
+                    ) {
                        self.add_check(check);
                    }
                }
@@ -445,6 +478,7 @@ where
                        name,
                        body,
                        self.settings.mccabe.max_complexity,
+                        self.locator,
                    ) {
                        self.add_check(check);
                    }
@@ -460,7 +494,7 @@ where
                    pylint::plugins::property_with_parameters(self, stmt, decorator_list, args);
                }

-                self.check_builtin_shadowing(name, Range::from_located(stmt), true);
+                self.check_builtin_shadowing(name, stmt, true);

                // Visit the decorators and arguments, but avoid the body, which will be
                // deferred.
@@ -548,7 +582,9 @@ where
                }

                if self.settings.enabled.contains(&CheckCode::N801) {
-                    if let Some(check) = pep8_naming::checks::invalid_class_name(stmt, name) {
+                    if let Some(check) =
+                        pep8_naming::checks::invalid_class_name(stmt, name, self.locator)
+                    {
                        self.add_check(check);
                    }
                }
@@ -573,7 +609,7 @@ where
                    );
                }

-                self.check_builtin_shadowing(name, Range::from_located(stmt), false);
+                self.check_builtin_shadowing(name, stmt, false);

                for expr in bases {
                    self.visit_expr(expr);
@@ -615,7 +651,7 @@ where
                        );
                    } else {
                        if let Some(asname) = &alias.node.asname {
-                            self.check_builtin_shadowing(asname, Range::from_located(stmt), false);
+                            self.check_builtin_shadowing(asname, stmt, false);
                        }

                        // Given `import foo`, `name` and `full_name` would both be `foo`.
@@ -683,7 +719,10 @@ where
                        if self.settings.enabled.contains(&CheckCode::N811) {
                            if let Some(check) =
                                pep8_naming::checks::constant_imported_as_non_constant(
-                                    stmt, name, asname,
+                                    stmt,
+                                    name,
+                                    asname,
+                                    self.locator,
                                )
                            {
                                self.add_check(check);
@@ -693,7 +732,10 @@ where
                        if self.settings.enabled.contains(&CheckCode::N812) {
                            if let Some(check) =
                                pep8_naming::checks::lowercase_imported_as_non_lowercase(
-                                    stmt, name, asname,
+                                    stmt,
+                                    name,
+                                    asname,
+                                    self.locator,
                                )
                            {
                                self.add_check(check);
@@ -703,7 +745,10 @@ where
                        if self.settings.enabled.contains(&CheckCode::N813) {
                            if let Some(check) =
                                pep8_naming::checks::camelcase_imported_as_lowercase(
-                                    stmt, name, asname,
+                                    stmt,
+                                    name,
+                                    asname,
+                                    self.locator,
                                )
                            {
                                self.add_check(check);
@@ -712,7 +757,10 @@ where

                        if self.settings.enabled.contains(&CheckCode::N814) {
                            if let Some(check) = pep8_naming::checks::camelcase_imported_as_constant(
-                                stmt, name, asname,
+                                stmt,
+                                name,
+                                asname,
+                                self.locator,
                            ) {
                                self.add_check(check);
                            }
@@ -720,7 +768,10 @@ where

                        if self.settings.enabled.contains(&CheckCode::N817) {
                            if let Some(check) = pep8_naming::checks::camelcase_imported_as_acronym(
-                                stmt, name, asname,
+                                stmt,
+                                name,
+                                asname,
+                                self.locator,
                            ) {
                                self.add_check(check);
                            }
@@ -858,7 +909,7 @@ where
                        scope.import_starred = true;
                    } else {
                        if let Some(asname) = &alias.node.asname {
-                            self.check_builtin_shadowing(asname, Range::from_located(stmt), false);
+                            self.check_builtin_shadowing(asname, stmt, false);
                        }

                        // Given `from foo import bar`, `name` would be "bar" and `full_name` would
@@ -927,6 +978,7 @@ where
                                    stmt,
                                    &alias.node.name,
                                    asname,
+                                    self.locator,
                                )
                            {
                                self.add_check(check);
@@ -939,6 +991,7 @@ where
                                    stmt,
                                    &alias.node.name,
                                    asname,
+                                    self.locator,
                                )
                            {
                                self.add_check(check);
@@ -951,6 +1004,7 @@ where
                                    stmt,
                                    &alias.node.name,
                                    asname,
+                                    self.locator,
                                )
                            {
                                self.add_check(check);
@@ -962,6 +1016,7 @@ where
                                stmt,
                                &alias.node.name,
                                asname,
+                                self.locator,
                            ) {
                                self.add_check(check);
                            }
@@ -972,6 +1027,7 @@ where
                                stmt,
                                &alias.node.name,
                                asname,
+                                self.locator,
                            ) {
                                self.add_check(check);
                            }
@@ -995,6 +1051,20 @@ 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 {
+                        self.add_checks(
+                            flake8_errmsg::checks::check_string_in_exception(
+                                exc,
+                                self.settings.flake8_errmsg.max_string_length,
+                            )
+                            .into_iter(),
+                        );
+                    }
+                }
            }
            StmtKind::AugAssign { target, .. } => {
                self.handle_node_load(target);
@@ -1107,6 +1177,11 @@ where
                        self, stmt, targets, value,
                    );
                }
+                if self.settings.enabled.contains(&CheckCode::PDV901) {
+                    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) {
@@ -1422,15 +1497,14 @@ where
                    }
                    ExprContext::Store => {
                        if self.settings.enabled.contains(&CheckCode::E741) {
-                            if let Some(check) = pycodestyle::checks::ambiguous_variable_name(
-                                id,
-                                Range::from_located(expr),
-                            ) {
+                            if let Some(check) =
+                                pycodestyle::checks::ambiguous_variable_name(id, expr)
+                            {
                                self.add_check(check);
                            }
                        }

-                        self.check_builtin_shadowing(id, Range::from_located(expr), true);
+                        self.check_builtin_shadowing(id, expr, true);

                        self.handle_node_store(id, expr);
                    }
@@ -1458,9 +1532,26 @@ 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::YTT202) {
                    flake8_2020::plugins::name_or_attribute(self, expr);
                }
+
+                for (code, name) in vec![
+                    (CheckCode::PDV007, "ix"),
+                    (CheckCode::PDV008, "at"),
+                    (CheckCode::PDV009, "iat"),
+                    (CheckCode::PDV011, "values"),
+                ] {
+                    if self.settings.enabled.contains(&code) {
+                        if attr == name {
+                            self.add_check(Check::new(code.kind(), Range::from_located(expr)));
+                        };
+                    }
+                }
            }
            ExprKind::Call {
                func,
@@ -1533,6 +1624,9 @@ 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);
+                }

                // flake8-super
                if self.settings.enabled.contains(&CheckCode::UP008) {
@@ -1557,14 +1651,7 @@ where
                    flake8_bugbear::plugins::getattr_with_constant(self, expr, func, args);
                }
                if self.settings.enabled.contains(&CheckCode::B010) {
-                    if !self
-                        .scope_stack
-                        .iter()
-                        .rev()
-                        .any(|index| matches!(self.scopes[*index].kind, ScopeKind::Lambda(..)))
-                    {
-                        flake8_bugbear::plugins::setattr_with_constant(self, expr, func, args);
-                    }
+                    flake8_bugbear::plugins::setattr_with_constant(self, expr, func, args);
                }
                if self.settings.enabled.contains(&CheckCode::B022) {
                    flake8_bugbear::plugins::useless_contextlib_suppress(self, expr, args);
@@ -1838,6 +1925,34 @@ where
                    }
                }

+                // pandas-vet
+                if self.settings.enabled.contains(&CheckCode::PDV002) {
+                    self.add_checks(pandas_vet::checks::inplace_argument(keywords).into_iter());
+                }
+
+                for (code, name) in vec![
+                    (CheckCode::PDV003, "isnull"),
+                    (CheckCode::PDV004, "notnull"),
+                    (CheckCode::PDV010, "pivot"),
+                    (CheckCode::PDV010, "unstack"),
+                    (CheckCode::PDV012, "read_table"),
+                    (CheckCode::PDV013, "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::PDV015) {
+                    if let Some(check) = pandas_vet::checks::use_of_pd_merge(func) {
+                        self.add_check(check);
+                    };
+                }
+
                // pygrep-hooks
                if self.settings.enabled.contains(&CheckCode::PGH001) {
                    pygrep_hooks::checks::no_eval(self, func);
@@ -2420,19 +2535,14 @@ where
                match name {
                    Some(name) => {
                        if self.settings.enabled.contains(&CheckCode::E741) {
-                            if let Some(check) = pycodestyle::checks::ambiguous_variable_name(
-                                name,
-                                Range::from_located(excepthandler),
-                            ) {
+                            if let Some(check) =
+                                pycodestyle::checks::ambiguous_variable_name(name, excepthandler)
+                            {
                                self.add_check(check);
                            }
                        }

-                        self.check_builtin_shadowing(
-                            name,
-                            Range::from_located(excepthandler),
-                            false,
-                        );
+                        self.check_builtin_shadowing(name, excepthandler, false);

                        if self.current_scope().values.contains_key(&name.as_str()) {
                            self.handle_node_store(
@@ -2545,23 +2655,18 @@ where
        );

        if self.settings.enabled.contains(&CheckCode::E741) {
-            if let Some(check) = pycodestyle::checks::ambiguous_variable_name(
-                &arg.node.arg,
-                Range::from_located(arg),
-            ) {
+            if let Some(check) = pycodestyle::checks::ambiguous_variable_name(&arg.node.arg, arg) {
                self.add_check(check);
            }
        }

        if self.settings.enabled.contains(&CheckCode::N803) {
-            if let Some(check) =
-                pep8_naming::checks::invalid_argument_name(&arg.node.arg, Range::from_located(arg))
-            {
+            if let Some(check) = pep8_naming::checks::invalid_argument_name(&arg.node.arg, arg) {
                self.add_check(check);
            }
        }

-        self.check_builtin_arg_shadowing(&arg.node.arg, Range::from_located(arg));
+        self.check_builtin_arg_shadowing(&arg.node.arg, arg);
    }
 }

@@ -3322,6 +3427,8 @@ 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
@@ -3346,12 +3453,21 @@ 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)
@@ -3359,17 +3475,15 @@ 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" {
@@ -3397,6 +3511,17 @@ 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());
@@ -3591,12 +3716,12 @@ impl<'a> Checker<'a> {
        }
    }

-    fn check_builtin_shadowing(&mut self, name: &str, location: Range, is_attribute: bool) {
+    fn check_builtin_shadowing<T>(&mut self, name: &str, located: &Located<T>, is_attribute: bool) {
        if is_attribute && matches!(self.current_scope().kind, ScopeKind::Class(_)) {
            if self.settings.enabled.contains(&CheckCode::A003) {
                if let Some(check) = flake8_builtins::checks::builtin_shadowing(
                    name,
-                    location,
+                    located,
                    flake8_builtins::types::ShadowingType::Attribute,
                ) {
                    self.add_check(check);
@@ -3606,7 +3731,7 @@ impl<'a> Checker<'a> {
            if self.settings.enabled.contains(&CheckCode::A001) {
                if let Some(check) = flake8_builtins::checks::builtin_shadowing(
                    name,
-                    location,
+                    located,
                    flake8_builtins::types::ShadowingType::Variable,
                ) {
                    self.add_check(check);
@@ -3615,11 +3740,11 @@ impl<'a> Checker<'a> {
        }
    }

-    fn check_builtin_arg_shadowing(&mut self, name: &str, location: Range) {
+    fn check_builtin_arg_shadowing(&mut self, name: &str, arg: &Arg) {
        if self.settings.enabled.contains(&CheckCode::A002) {
            if let Some(check) = flake8_builtins::checks::builtin_shadowing(
                name,
-                location,
+                arg,
                flake8_builtins::types::ShadowingType::Argument,
            ) {
                self.add_check(check);
@@ -3631,11 +3756,13 @@ impl<'a> Checker<'a> {
 pub fn check_ast(
    python_ast: &Suite,
    locator: &SourceCodeLocator,
+    noqa_line_for: &IntMap<usize, usize>,
    settings: &Settings,
    autofix: bool,
+    ignore_noqa: bool,
    path: &Path,
 ) -> Vec<Check> {
-    let mut checker = Checker::new(settings, autofix, path, locator);
+    let mut checker = Checker::new(settings, noqa_line_for, autofix, ignore_noqa, path, locator);
    checker.push_scope(Scope::new(ScopeKind::Module));
    checker.bind_builtins();

--- a/src/checks.rs
+++ b/src/checks.rs
@@ -223,6 +223,7 @@ pub enum CheckCode {
    UP013,
    UP014,
    UP015,
+    UP016,
    // pydocstyle
    D100,
    D101,
@@ -315,6 +316,23 @@ pub enum CheckCode {
    RUF100,
    // pygrep-hooks
    PGH001,
+    // pandas-vet
+    PDV002,
+    PDV003,
+    PDV004,
+    PDV007,
+    PDV008,
+    PDV009,
+    PDV010,
+    PDV011,
+    PDV012,
+    PDV013,
+    PDV015,
+    PDV901,
+    // flake8-errmsg
+    EM101,
+    EM102,
+    EM103,
 }

 #[derive(EnumIter, Debug, PartialEq, Eq)]
@@ -335,6 +353,7 @@ pub enum CheckCategory {
    Flake8Builtins,
    Flake8Comprehensions,
    Flake8Debugger,
+    Flake8ErrMsg,
    Flake8ImportConventions,
    Flake8Print,
    Flake8Quotes,
@@ -343,6 +362,7 @@ pub enum CheckCategory {
    Flake8TidyImports,
    Flake8UnusedArguments,
    Eradicate,
+    PandasVet,
    PygrepHooks,
    Pylint,
    Ruff,
@@ -375,6 +395,7 @@ impl CheckCategory {
            CheckCategory::Flake8Builtins => "flake8-builtins",
            CheckCategory::Flake8Comprehensions => "flake8-comprehensions",
            CheckCategory::Flake8Debugger => "flake8-debugger",
+            CheckCategory::Flake8ErrMsg => "flake8-errmsg",
            CheckCategory::Flake8ImportConventions => "flake8-import-conventions",
            CheckCategory::Flake8Print => "flake8-print",
            CheckCategory::Flake8Quotes => "flake8-quotes",
@@ -384,6 +405,7 @@ impl CheckCategory {
            CheckCategory::Flake8UnusedArguments => "flake8-unused-arguments",
            CheckCategory::Isort => "isort",
            CheckCategory::McCabe => "mccabe",
+            CheckCategory::PandasVet => "pandas-vet",
            CheckCategory::PEP8Naming => "pep8-naming",
            CheckCategory::Pycodestyle => "pycodestyle",
            CheckCategory::Pydocstyle => "pydocstyle",
@@ -407,6 +429,7 @@ impl CheckCategory {
            CheckCategory::Flake8Builtins => vec![CheckCodePrefix::A],
            CheckCategory::Flake8Comprehensions => vec![CheckCodePrefix::C4],
            CheckCategory::Flake8Debugger => vec![CheckCodePrefix::T10],
+            CheckCategory::Flake8ErrMsg => vec![CheckCodePrefix::EM],
            CheckCategory::Flake8Print => vec![CheckCodePrefix::T20],
            CheckCategory::Flake8Quotes => vec![CheckCodePrefix::Q],
            CheckCategory::Flake8Return => vec![CheckCodePrefix::RET],
@@ -415,6 +438,7 @@ impl CheckCategory {
            CheckCategory::Flake8UnusedArguments => vec![CheckCodePrefix::ARG],
            CheckCategory::Isort => vec![CheckCodePrefix::I],
            CheckCategory::McCabe => vec![CheckCodePrefix::C90],
+            CheckCategory::PandasVet => vec![CheckCodePrefix::PDV],
            CheckCategory::PEP8Naming => vec![CheckCodePrefix::N],
            CheckCategory::Pycodestyle => vec![CheckCodePrefix::E, CheckCodePrefix::W],
            CheckCategory::Pydocstyle => vec![CheckCodePrefix::D],
@@ -473,6 +497,10 @@ impl CheckCategory {
                "https://pypi.org/project/flake8-debugger/4.1.2/",
                &Platform::PyPI,
            )),
+            CheckCategory::Flake8ErrMsg => Some((
+                "https://pypi.org/project/flake8-errmsg/0.4.0/",
+                &Platform::PyPI,
+            )),
            CheckCategory::Flake8ImportConventions => None,
            CheckCategory::Flake8Print => Some((
                "https://pypi.org/project/flake8-print/5.0.0/",
@@ -504,6 +532,10 @@ impl CheckCategory {
            CheckCategory::McCabe => {
                Some(("https://pypi.org/project/mccabe/0.7.0/", &Platform::PyPI))
            }
+            CheckCategory::PandasVet => Some((
+                "https://pypi.org/project/pandas-vet/0.2.3/",
+                &Platform::PyPI,
+            )),
            CheckCategory::PEP8Naming => Some((
                "https://pypi.org/project/pep8-naming/0.13.2/",
                &Platform::PyPI,
@@ -772,6 +804,7 @@ pub enum CheckKind {
    ConvertTypedDictFunctionalToClass(String),
    ConvertNamedTupleFunctionalToClass(String),
    RedundantOpenModes,
+    RemoveSixCompat,
    // pydocstyle
    BlankLineAfterLastSection(String),
    BlankLineAfterSection(String),
@@ -861,6 +894,23 @@ pub enum CheckKind {
    UnusedLambdaArgument(String),
    // flake8-import-conventions
    ImportAliasIsNotConventional(String, String),
+    // pandas-vet
+    UseOfInplaceArgument,
+    UseOfDotIsNull,
+    UseOfDotNotNull,
+    UseOfDotIx,
+    UseOfDotAt,
+    UseOfDotIat,
+    UseOfDotPivotOrUnstack,
+    UseOfDotValues,
+    UseOfDotReadTable,
+    UseOfDotStack,
+    UseOfPdMerge,
+    DfIsABadVariableName,
+    // flake8-errmsg
+    RawStringInException,
+    FStringInException,
+    DotFormatInException,
    // Ruff
    AmbiguousUnicodeCharacterString(char, char),
    AmbiguousUnicodeCharacterDocstring(char, char),
@@ -1113,6 +1163,7 @@ impl CheckCode {
            CheckCode::UP013 => CheckKind::ConvertTypedDictFunctionalToClass("...".to_string()),
            CheckCode::UP014 => CheckKind::ConvertNamedTupleFunctionalToClass("...".to_string()),
            CheckCode::UP015 => CheckKind::RedundantOpenModes,
+            CheckCode::UP016 => CheckKind::RemoveSixCompat,
            // pydocstyle
            CheckCode::D100 => CheckKind::PublicModule,
            CheckCode::D101 => CheckKind::PublicClass,
@@ -1219,6 +1270,23 @@ impl CheckCode {
            CheckCode::ICN001 => {
                CheckKind::ImportAliasIsNotConventional("...".to_string(), "...".to_string())
            }
+            // pandas-vet
+            CheckCode::PDV002 => CheckKind::UseOfInplaceArgument,
+            CheckCode::PDV003 => CheckKind::UseOfDotIsNull,
+            CheckCode::PDV004 => CheckKind::UseOfDotNotNull,
+            CheckCode::PDV007 => CheckKind::UseOfDotIx,
+            CheckCode::PDV008 => CheckKind::UseOfDotAt,
+            CheckCode::PDV009 => CheckKind::UseOfDotIat,
+            CheckCode::PDV010 => CheckKind::UseOfDotPivotOrUnstack,
+            CheckCode::PDV011 => CheckKind::UseOfDotValues,
+            CheckCode::PDV012 => CheckKind::UseOfDotReadTable,
+            CheckCode::PDV013 => CheckKind::UseOfDotStack,
+            CheckCode::PDV015 => CheckKind::UseOfPdMerge,
+            CheckCode::PDV901 => CheckKind::DfIsABadVariableName,
+            // flake8-errmsg
+            CheckCode::EM101 => CheckKind::RawStringInException,
+            CheckCode::EM102 => CheckKind::FStringInException,
+            CheckCode::EM103 => CheckKind::DotFormatInException,
            // Ruff
            CheckCode::RUF001 => CheckKind::AmbiguousUnicodeCharacterString('𝐁', 'B'),
            CheckCode::RUF002 => CheckKind::AmbiguousUnicodeCharacterDocstring('𝐁', 'B'),
@@ -1354,6 +1422,9 @@ impl CheckCode {
            CheckCode::E743 => CheckCategory::Pycodestyle,
            CheckCode::E902 => CheckCategory::Pycodestyle,
            CheckCode::E999 => CheckCategory::Pycodestyle,
+            CheckCode::EM101 => CheckCategory::Flake8ErrMsg,
+            CheckCode::EM102 => CheckCategory::Flake8ErrMsg,
+            CheckCode::EM103 => CheckCategory::Flake8ErrMsg,
            CheckCode::ERA001 => CheckCategory::Eradicate,
            CheckCode::F401 => CheckCategory::Pyflakes,
            CheckCode::F402 => CheckCategory::Pyflakes,
@@ -1420,6 +1491,18 @@ impl CheckCode {
            CheckCode::N816 => CheckCategory::PEP8Naming,
            CheckCode::N817 => CheckCategory::PEP8Naming,
            CheckCode::N818 => CheckCategory::PEP8Naming,
+            CheckCode::PDV002 => CheckCategory::PandasVet,
+            CheckCode::PDV003 => CheckCategory::PandasVet,
+            CheckCode::PDV004 => CheckCategory::PandasVet,
+            CheckCode::PDV007 => CheckCategory::PandasVet,
+            CheckCode::PDV008 => CheckCategory::PandasVet,
+            CheckCode::PDV009 => CheckCategory::PandasVet,
+            CheckCode::PDV010 => CheckCategory::PandasVet,
+            CheckCode::PDV011 => CheckCategory::PandasVet,
+            CheckCode::PDV012 => CheckCategory::PandasVet,
+            CheckCode::PDV013 => CheckCategory::PandasVet,
+            CheckCode::PDV015 => CheckCategory::PandasVet,
+            CheckCode::PDV901 => CheckCategory::PandasVet,
            CheckCode::PGH001 => CheckCategory::PygrepHooks,
            CheckCode::PLC0414 => CheckCategory::Pylint,
            CheckCode::PLC2201 => CheckCategory::Pylint,
@@ -1473,6 +1556,7 @@ impl CheckCode {
            CheckCode::UP013 => CheckCategory::Pyupgrade,
            CheckCode::UP014 => CheckCategory::Pyupgrade,
            CheckCode::UP015 => CheckCategory::Pyupgrade,
+            CheckCode::UP016 => CheckCategory::Pyupgrade,
            CheckCode::W292 => CheckCategory::Pycodestyle,
            CheckCode::W605 => CheckCategory::Pycodestyle,
            CheckCode::YTT101 => CheckCategory::Flake82020,
@@ -1681,6 +1765,7 @@ impl CheckKind {
            CheckKind::ConvertTypedDictFunctionalToClass(_) => &CheckCode::UP013,
            CheckKind::ConvertNamedTupleFunctionalToClass(_) => &CheckCode::UP014,
            CheckKind::RedundantOpenModes => &CheckCode::UP015,
+            CheckKind::RemoveSixCompat => &CheckCode::UP016,
            // pydocstyle
            CheckKind::BlankLineAfterLastSection(_) => &CheckCode::D413,
            CheckKind::BlankLineAfterSection(_) => &CheckCode::D410,
@@ -1770,6 +1855,23 @@ impl CheckKind {
            CheckKind::UnusedLambdaArgument(..) => &CheckCode::ARG005,
            // flake8-import-conventions
            CheckKind::ImportAliasIsNotConventional(..) => &CheckCode::ICN001,
+            // pandas-vet
+            CheckKind::UseOfInplaceArgument => &CheckCode::PDV002,
+            CheckKind::UseOfDotIsNull => &CheckCode::PDV003,
+            CheckKind::UseOfDotNotNull => &CheckCode::PDV004,
+            CheckKind::UseOfDotIx => &CheckCode::PDV007,
+            CheckKind::UseOfDotAt => &CheckCode::PDV008,
+            CheckKind::UseOfDotIat => &CheckCode::PDV009,
+            CheckKind::UseOfDotPivotOrUnstack => &CheckCode::PDV010,
+            CheckKind::UseOfDotValues => &CheckCode::PDV011,
+            CheckKind::UseOfDotReadTable => &CheckCode::PDV012,
+            CheckKind::UseOfDotStack => &CheckCode::PDV013,
+            CheckKind::UseOfPdMerge => &CheckCode::PDV015,
+            CheckKind::DfIsABadVariableName => &CheckCode::PDV901,
+            // flake8-errmsg
+            CheckKind::RawStringInException => &CheckCode::EM101,
+            CheckKind::FStringInException => &CheckCode::EM102,
+            CheckKind::DotFormatInException => &CheckCode::EM103,
            // Ruff
            CheckKind::AmbiguousUnicodeCharacterString(..) => &CheckCode::RUF001,
            CheckKind::AmbiguousUnicodeCharacterDocstring(..) => &CheckCode::RUF002,
@@ -2372,6 +2474,7 @@ impl CheckKind {
            }
            CheckKind::UnnecessaryEncodeUTF8 => "Unnecessary call to `encode` as UTF-8".to_string(),
            CheckKind::RedundantOpenModes => "Unnecessary open mode parameters".to_string(),
+            CheckKind::RemoveSixCompat => "Unnecessary `six` compatibility usage".to_string(),
            CheckKind::ConvertTypedDictFunctionalToClass(name) => {
                format!("Convert `{name}` from `TypedDict` functional to class syntax")
            }
@@ -2597,6 +2700,51 @@ impl CheckKind {
            CheckKind::ImportAliasIsNotConventional(name, asname) => {
                format!("`{name}` should be imported as `{asname}`")
            }
+            // pandas-vet
+            CheckKind::UseOfInplaceArgument => {
+                "`inplace=True` should be avoided; it has inconsistent behavior".to_string()
+            }
+            CheckKind::UseOfDotIsNull => {
+                "`.isna` is preferred to `.isnull`; functionality is equivalent".to_string()
+            }
+            CheckKind::UseOfDotNotNull => {
+                "`.notna` is preferred to `.notnull`; functionality is equivalent".to_string()
+            }
+            CheckKind::UseOfDotIx => {
+                "``ix` i` deprecated; use more explicit `.loc` o` `.iloc`".to_string()
+            }
+            CheckKind::UseOfDotAt => {
+                "Use `.loc` instead of `.at`.  If speed is important, use numpy.".to_string()
+            }
+            CheckKind::UseOfDotIat => {
+                "Use `.iloc` instea` of `.iat`.  If speed is important, use numpy.".to_string()
+            }
+            CheckKind::UseOfDotPivotOrUnstack => "`.pivot_table` is preferred to `.pivot` or \
+                                                  `.unstack`; provides same functionality"
+                .to_string(),
+            CheckKind::UseOfDotValues => "Use `.to_numpy()` instead of `.values`".to_string(),
+            CheckKind::UseOfDotReadTable => {
+                "`.read_csv` is preferred to `.read_table`; provides same functionality".to_string()
+            }
+            CheckKind::UseOfDotStack => {
+                "`.melt` is preferred to `.stack`; provides same functionality".to_string()
+            }
+            CheckKind::DfIsABadVariableName => {
+                "`df` is a bad variable name. Be kinder to your future self.".to_string()
+            }
+            CheckKind::UseOfPdMerge => "Use `.merge` method instead of `pd.merge` function. They \
+                                        have equivalent functionality."
+                .to_string(),
+            // flake8-errmsg
+            CheckKind::RawStringInException => {
+                "Exception must not use a string literal, assign to variable first".to_string()
+            }
+            CheckKind::FStringInException => {
+                "Exception must not use an f-string literal, assign to variable first".to_string()
+            }
+            CheckKind::DotFormatInException => "Exception must not use a `.format()` string \
+                                                directly, assign to variable first"
+                .to_string(),
            // Ruff
            CheckKind::AmbiguousUnicodeCharacterString(confusable, representant) => {
                format!(
@@ -2669,6 +2817,7 @@ impl CheckKind {
                | CheckKind::CommentedOutCode
                | CheckKind::ConvertNamedTupleFunctionalToClass(..)
                | CheckKind::ConvertTypedDictFunctionalToClass(..)
+                | CheckKind::RemoveSixCompat
                | CheckKind::DashedUnderlineAfterSection(..)
                | CheckKind::DeprecatedUnittestAlias(..)
                | CheckKind::DoNotAssertFalse
@@ -2785,6 +2934,7 @@ pub static CODE_REDIRECTS: Lazy<FxHashMap<&'static str, CheckCode>> = Lazy::new(
        ("U013", CheckCode::UP013),
        ("U014", CheckCode::UP014),
        ("U015", CheckCode::UP015),
+        ("U016", CheckCode::UP016),
        // TODO(charlie): Remove by 2023-02-01.
        ("I252", CheckCode::TID252),
        ("M001", CheckCode::RUF100),
--- a/src/checks_gen.rs
+++ b/src/checks_gen.rs
@@ -189,6 +189,12 @@ pub enum CheckCodePrefix {
    E902,
    E99,
    E999,
+    EM,
+    EM1,
+    EM10,
+    EM101,
+    EM102,
+    EM103,
    ERA,
    ERA0,
    ERA00,
@@ -297,6 +303,24 @@ pub enum CheckCodePrefix {
    N816,
    N817,
    N818,
+    PDV,
+    PDV0,
+    PDV00,
+    PDV002,
+    PDV003,
+    PDV004,
+    PDV007,
+    PDV008,
+    PDV009,
+    PDV01,
+    PDV010,
+    PDV011,
+    PDV012,
+    PDV013,
+    PDV015,
+    PDV9,
+    PDV90,
+    PDV901,
    PGH,
    PGH0,
    PGH00,
@@ -416,6 +440,7 @@ pub enum CheckCodePrefix {
    U013,
    U014,
    U015,
+    U016,
    UP,
    UP0,
    UP00,
@@ -434,6 +459,7 @@ pub enum CheckCodePrefix {
    UP013,
    UP014,
    UP015,
+    UP016,
    W,
    W2,
    W29,
@@ -1003,6 +1029,12 @@ impl CheckCodePrefix {
            CheckCodePrefix::E902 => vec![CheckCode::E902],
            CheckCodePrefix::E99 => vec![CheckCode::E999],
            CheckCodePrefix::E999 => vec![CheckCode::E999],
+            CheckCodePrefix::EM => vec![CheckCode::EM101, CheckCode::EM102, CheckCode::EM103],
+            CheckCodePrefix::EM1 => vec![CheckCode::EM101, CheckCode::EM102, CheckCode::EM103],
+            CheckCodePrefix::EM10 => vec![CheckCode::EM101, CheckCode::EM102, CheckCode::EM103],
+            CheckCodePrefix::EM101 => vec![CheckCode::EM101],
+            CheckCodePrefix::EM102 => vec![CheckCode::EM102],
+            CheckCodePrefix::EM103 => vec![CheckCode::EM103],
            CheckCodePrefix::ERA => vec![CheckCode::ERA001],
            CheckCodePrefix::ERA0 => vec![CheckCode::ERA001],
            CheckCodePrefix::ERA00 => vec![CheckCode::ERA001],
@@ -1336,6 +1368,62 @@ impl CheckCodePrefix {
            CheckCodePrefix::N816 => vec![CheckCode::N816],
            CheckCodePrefix::N817 => vec![CheckCode::N817],
            CheckCodePrefix::N818 => vec![CheckCode::N818],
+            CheckCodePrefix::PDV => vec![
+                CheckCode::PDV002,
+                CheckCode::PDV003,
+                CheckCode::PDV004,
+                CheckCode::PDV007,
+                CheckCode::PDV008,
+                CheckCode::PDV009,
+                CheckCode::PDV010,
+                CheckCode::PDV011,
+                CheckCode::PDV012,
+                CheckCode::PDV013,
+                CheckCode::PDV015,
+                CheckCode::PDV901,
+            ],
+            CheckCodePrefix::PDV0 => vec![
+                CheckCode::PDV002,
+                CheckCode::PDV003,
+                CheckCode::PDV004,
+                CheckCode::PDV007,
+                CheckCode::PDV008,
+                CheckCode::PDV009,
+                CheckCode::PDV010,
+                CheckCode::PDV011,
+                CheckCode::PDV012,
+                CheckCode::PDV013,
+                CheckCode::PDV015,
+            ],
+            CheckCodePrefix::PDV00 => vec![
+                CheckCode::PDV002,
+                CheckCode::PDV003,
+                CheckCode::PDV004,
+                CheckCode::PDV007,
+                CheckCode::PDV008,
+                CheckCode::PDV009,
+            ],
+            CheckCodePrefix::PDV002 => vec![CheckCode::PDV002],
+            CheckCodePrefix::PDV003 => vec![CheckCode::PDV003],
+            CheckCodePrefix::PDV004 => vec![CheckCode::PDV004],
+            CheckCodePrefix::PDV007 => vec![CheckCode::PDV007],
+            CheckCodePrefix::PDV008 => vec![CheckCode::PDV008],
+            CheckCodePrefix::PDV009 => vec![CheckCode::PDV009],
+            CheckCodePrefix::PDV01 => vec![
+                CheckCode::PDV010,
+                CheckCode::PDV011,
+                CheckCode::PDV012,
+                CheckCode::PDV013,
+                CheckCode::PDV015,
+            ],
+            CheckCodePrefix::PDV010 => vec![CheckCode::PDV010],
+            CheckCodePrefix::PDV011 => vec![CheckCode::PDV011],
+            CheckCodePrefix::PDV012 => vec![CheckCode::PDV012],
+            CheckCodePrefix::PDV013 => vec![CheckCode::PDV013],
+            CheckCodePrefix::PDV015 => vec![CheckCode::PDV015],
+            CheckCodePrefix::PDV9 => vec![CheckCode::PDV901],
+            CheckCodePrefix::PDV90 => vec![CheckCode::PDV901],
+            CheckCodePrefix::PDV901 => vec![CheckCode::PDV901],
            CheckCodePrefix::PGH => vec![CheckCode::PGH001],
            CheckCodePrefix::PGH0 => vec![CheckCode::PGH001],
            CheckCodePrefix::PGH00 => vec![CheckCode::PGH001],
@@ -1536,6 +1624,7 @@ impl CheckCodePrefix {
                    CheckCode::UP013,
                    CheckCode::UP014,
                    CheckCode::UP015,
+                    CheckCode::UP016,
                ]
            }
            CheckCodePrefix::U0 => {
@@ -1560,6 +1649,7 @@ impl CheckCodePrefix {
                    CheckCode::UP013,
                    CheckCode::UP014,
                    CheckCode::UP015,
+                    CheckCode::UP016,
                ]
            }
            CheckCodePrefix::U00 => {
@@ -1666,6 +1756,7 @@ impl CheckCodePrefix {
                    CheckCode::UP013,
                    CheckCode::UP014,
                    CheckCode::UP015,
+                    CheckCode::UP016,
                ]
            }
            CheckCodePrefix::U010 => {
@@ -1722,6 +1813,15 @@ impl CheckCodePrefix {
                );
                vec![CheckCode::UP015]
            }
+            CheckCodePrefix::U016 => {
+                eprintln!(
+                    "{}{} {}",
+                    "warning".yellow().bold(),
+                    ":".bold(),
+                    "`U016` has been remapped to `UP016`".bold()
+                );
+                vec![CheckCode::UP016]
+            }
            CheckCodePrefix::UP => vec![
                CheckCode::UP001,
                CheckCode::UP003,
@@ -1737,6 +1837,7 @@ impl CheckCodePrefix {
                CheckCode::UP013,
                CheckCode::UP014,
                CheckCode::UP015,
+                CheckCode::UP016,
            ],
            CheckCodePrefix::UP0 => vec![
                CheckCode::UP001,
@@ -1753,6 +1854,7 @@ impl CheckCodePrefix {
                CheckCode::UP013,
                CheckCode::UP014,
                CheckCode::UP015,
+                CheckCode::UP016,
            ],
            CheckCodePrefix::UP00 => vec![
                CheckCode::UP001,
@@ -1779,6 +1881,7 @@ impl CheckCodePrefix {
                CheckCode::UP013,
                CheckCode::UP014,
                CheckCode::UP015,
+                CheckCode::UP016,
            ],
            CheckCodePrefix::UP010 => vec![CheckCode::UP010],
            CheckCodePrefix::UP011 => vec![CheckCode::UP011],
@@ -1786,6 +1889,7 @@ impl CheckCodePrefix {
            CheckCodePrefix::UP013 => vec![CheckCode::UP013],
            CheckCodePrefix::UP014 => vec![CheckCode::UP014],
            CheckCodePrefix::UP015 => vec![CheckCode::UP015],
+            CheckCodePrefix::UP016 => vec![CheckCode::UP016],
            CheckCodePrefix::W => vec![CheckCode::W292, CheckCode::W605],
            CheckCodePrefix::W2 => vec![CheckCode::W292],
            CheckCodePrefix::W29 => vec![CheckCode::W292],
@@ -2018,6 +2122,12 @@ impl CheckCodePrefix {
            CheckCodePrefix::E902 => SuffixLength::Three,
            CheckCodePrefix::E99 => SuffixLength::Two,
            CheckCodePrefix::E999 => SuffixLength::Three,
+            CheckCodePrefix::EM => SuffixLength::Zero,
+            CheckCodePrefix::EM1 => SuffixLength::One,
+            CheckCodePrefix::EM10 => SuffixLength::Two,
+            CheckCodePrefix::EM101 => SuffixLength::Three,
+            CheckCodePrefix::EM102 => SuffixLength::Three,
+            CheckCodePrefix::EM103 => SuffixLength::Three,
            CheckCodePrefix::ERA => SuffixLength::Zero,
            CheckCodePrefix::ERA0 => SuffixLength::One,
            CheckCodePrefix::ERA00 => SuffixLength::Two,
@@ -2126,6 +2236,24 @@ impl CheckCodePrefix {
            CheckCodePrefix::N816 => SuffixLength::Three,
            CheckCodePrefix::N817 => SuffixLength::Three,
            CheckCodePrefix::N818 => SuffixLength::Three,
+            CheckCodePrefix::PDV => SuffixLength::Zero,
+            CheckCodePrefix::PDV0 => SuffixLength::One,
+            CheckCodePrefix::PDV00 => SuffixLength::Two,
+            CheckCodePrefix::PDV002 => SuffixLength::Three,
+            CheckCodePrefix::PDV003 => SuffixLength::Three,
+            CheckCodePrefix::PDV004 => SuffixLength::Three,
+            CheckCodePrefix::PDV007 => SuffixLength::Three,
+            CheckCodePrefix::PDV008 => SuffixLength::Three,
+            CheckCodePrefix::PDV009 => SuffixLength::Three,
+            CheckCodePrefix::PDV01 => SuffixLength::Two,
+            CheckCodePrefix::PDV010 => SuffixLength::Three,
+            CheckCodePrefix::PDV011 => SuffixLength::Three,
+            CheckCodePrefix::PDV012 => SuffixLength::Three,
+            CheckCodePrefix::PDV013 => SuffixLength::Three,
+            CheckCodePrefix::PDV015 => SuffixLength::Three,
+            CheckCodePrefix::PDV9 => SuffixLength::One,
+            CheckCodePrefix::PDV90 => SuffixLength::Two,
+            CheckCodePrefix::PDV901 => SuffixLength::Three,
            CheckCodePrefix::PGH => SuffixLength::Zero,
            CheckCodePrefix::PGH0 => SuffixLength::One,
            CheckCodePrefix::PGH00 => SuffixLength::Two,
@@ -2245,6 +2373,7 @@ impl CheckCodePrefix {
            CheckCodePrefix::U013 => SuffixLength::Three,
            CheckCodePrefix::U014 => SuffixLength::Three,
            CheckCodePrefix::U015 => SuffixLength::Three,
+            CheckCodePrefix::U016 => SuffixLength::Three,
            CheckCodePrefix::UP => SuffixLength::Zero,
            CheckCodePrefix::UP0 => SuffixLength::One,
            CheckCodePrefix::UP00 => SuffixLength::Two,
@@ -2263,6 +2392,7 @@ impl CheckCodePrefix {
            CheckCodePrefix::UP013 => SuffixLength::Three,
            CheckCodePrefix::UP014 => SuffixLength::Three,
            CheckCodePrefix::UP015 => SuffixLength::Three,
+            CheckCodePrefix::UP016 => SuffixLength::Three,
            CheckCodePrefix::W => SuffixLength::Zero,
            CheckCodePrefix::W2 => SuffixLength::One,
            CheckCodePrefix::W29 => SuffixLength::Two,
@@ -2300,12 +2430,14 @@ pub const CATEGORIES: &[CheckCodePrefix] = &[
    CheckCodePrefix::C,
    CheckCodePrefix::D,
    CheckCodePrefix::E,
+    CheckCodePrefix::EM,
    CheckCodePrefix::ERA,
    CheckCodePrefix::F,
    CheckCodePrefix::FBT,
    CheckCodePrefix::I,
    CheckCodePrefix::ICN,
    CheckCodePrefix::N,
+    CheckCodePrefix::PDV,
    CheckCodePrefix::PGH,
    CheckCodePrefix::PLC,
    CheckCodePrefix::PLE,
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -1,4 +1,4 @@
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};

 use clap::{command, Parser};
 use regex::Regex;
@@ -6,6 +6,7 @@ use rustc_hash::FxHashMap;

 use crate::checks::CheckCode;
 use crate::checks_gen::CheckCodePrefix;
+use crate::fs;
 use crate::logging::LogLevel;
 use crate::settings::types::{
    FilePattern, PatternPrefixPair, PerFileIgnore, PythonVersion, SerializationFormat,
@@ -85,10 +86,16 @@ pub struct Cli {
    show_source: bool,
    #[clap(long, overrides_with("show_source"), hide = true)]
    no_show_source: bool,
+    /// Respect file exclusions via `.gitignore` and other standard ignore
+    /// files.
+    #[arg(long, overrides_with("no_respect_gitignore"))]
+    respect_gitignore: bool,
+    #[clap(long, overrides_with("respect_gitignore"), hide = true)]
+    no_respect_gitignore: bool,
    /// See the files Ruff will be run against with the current settings.
    #[arg(long)]
    pub show_files: bool,
-    /// See Ruff's settings.
+    /// See the settings Ruff will use to check a given Python file.
    #[arg(long)]
    pub show_settings: bool,
    /// Enable automatic additions of noqa directives to failing lines.
@@ -155,6 +162,10 @@ impl Cli {
                line_length: self.line_length,
                max_complexity: self.max_complexity,
                per_file_ignores: self.per_file_ignores,
+                respect_gitignore: resolve_bool_arg(
+                    self.respect_gitignore,
+                    self.no_respect_gitignore,
+                ),
                select: self.select,
                show_source: resolve_bool_arg(self.show_source, self.no_show_source),
                target_version: self.target_version,
@@ -198,6 +209,7 @@ pub struct Arguments {
 }

 /// CLI settings that function as configuration overrides.
+#[derive(Clone)]
 #[allow(clippy::struct_excessive_bools)]
 pub struct Overrides {
    pub dummy_variable_rgx: Option<Regex>,
@@ -210,6 +222,7 @@ pub struct Overrides {
    pub line_length: Option<usize>,
    pub max_complexity: Option<usize>,
    pub per_file_ignores: Option<Vec<PatternPrefixPair>>,
+    pub respect_gitignore: Option<bool>,
    pub select: Option<Vec<CheckCodePrefix>>,
    pub show_source: Option<bool>,
    pub target_version: Option<PythonVersion>,
@@ -243,6 +256,9 @@ pub fn collect_per_file_ignores(pairs: Vec<PatternPrefixPair>) -> Vec<PerFileIgn
    }
    per_file_ignores
        .into_iter()
-        .map(|(pattern, prefixes)| PerFileIgnore::new(pattern, &prefixes))
+        .map(|(pattern, prefixes)| {
+            let absolute = fs::normalize_path(Path::new(&pattern));
+            PerFileIgnore::new(pattern, absolute, &prefixes)
+        })
        .collect()
 }
--- a/src/commands.rs
+++ b/src/commands.rs
@@ -1,36 +1,238 @@
-use std::path::PathBuf;
+use std::io::{self, Read};
+use std::path::{Path, PathBuf};
+use std::time::Instant;

 use anyhow::{bail, Result};
+use ignore::Error;
+use itertools::Itertools;
+use log::{debug, error};
+#[cfg(not(target_family = "wasm"))]
+use rayon::prelude::*;
+use rustpython_ast::Location;
 use serde::Serialize;
-use walkdir::DirEntry;

-use crate::checks::CheckCode;
-use crate::fs::iter_python_files;
+use crate::autofix::fixer;
+use crate::checks::{CheckCode, CheckKind};
+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::types::SerializationFormat;
-use crate::{Configuration, Settings};
+
+/// Run the linter over a collection of files.
+pub fn run(
+    files: &[PathBuf],
+    pyproject_strategy: &PyprojectDiscovery,
+    file_strategy: &FileDiscovery,
+    overrides: &Overrides,
+    cache: bool,
+    autofix: &fixer::Mode,
+) -> Result<Diagnostics> {
+    // Collect all the 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);
+
+    let start = Instant::now();
+    let mut diagnostics: Diagnostics = par_iter(&paths)
+        .map(|entry| {
+            match entry {
+                Ok(entry) => {
+                    let path = entry.path();
+                    let settings = resolver.resolve(path, pyproject_strategy);
+                    lint_path(path, settings, &cache.into(), autofix)
+                        .map_err(|e| (Some(path.to_owned()), e.to_string()))
+                }
+                Err(e) => Err((
+                    if let Error::WithPath { path, .. } = e {
+                        Some(path.clone())
+                    } else {
+                        None
+                    },
+                    e.io_error()
+                        .map_or_else(|| e.to_string(), io::Error::to_string),
+                )),
+            }
+            .unwrap_or_else(|(path, message)| {
+                if let Some(path) = &path {
+                    let settings = resolver.resolve(path, pyproject_strategy);
+                    if settings.enabled.contains(&CheckCode::E902) {
+                        Diagnostics::new(vec![Message {
+                            kind: CheckKind::IOError(message),
+                            location: Location::default(),
+                            end_location: Location::default(),
+                            fix: None,
+                            filename: path.to_string_lossy().to_string(),
+                            source: None,
+                        }])
+                    } else {
+                        error!("Failed to check {}: {message}", path.to_string_lossy());
+                        Diagnostics::default()
+                    }
+                } else {
+                    error!("{message}");
+                    Diagnostics::default()
+                }
+            })
+        })
+        .reduce(Diagnostics::default, |mut acc, item| {
+            acc += item;
+            acc
+        });
+
+    diagnostics.messages.sort_unstable();
+    let duration = start.elapsed();
+    debug!("Checked files in: {:?}", duration);
+
+    Ok(diagnostics)
+}
+
+/// Read a `String` from `stdin`.
+fn read_from_stdin() -> Result<String> {
+    let mut buffer = String::new();
+    io::stdin().lock().read_to_string(&mut buffer)?;
+    Ok(buffer)
+}
+
+/// Run the linter over a single file, read from `stdin`.
+pub fn run_stdin(
+    strategy: &PyprojectDiscovery,
+    filename: &Path,
+    autofix: &fixer::Mode,
+) -> Result<Diagnostics> {
+    let stdin = read_from_stdin()?;
+    let settings = match strategy {
+        PyprojectDiscovery::Fixed(settings) => settings,
+        PyprojectDiscovery::Hierarchical(settings) => settings,
+    };
+    let mut diagnostics = lint_stdin(filename, &stdin, settings, autofix)?;
+    diagnostics.messages.sort_unstable();
+    Ok(diagnostics)
+}
+
+/// Add `noqa` directives to a collection of files.
+pub fn add_noqa(
+    files: &[PathBuf],
+    pyproject_strategy: &PyprojectDiscovery,
+    file_strategy: &FileDiscovery,
+    overrides: &Overrides,
+) -> Result<usize> {
+    // Collect all the 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);
+
+    let start = Instant::now();
+    let modifications: usize = par_iter(&paths)
+        .flatten()
+        .filter_map(|entry| {
+            let path = entry.path();
+            let settings = resolver.resolve(path, pyproject_strategy);
+            match add_noqa_to_path(path, settings) {
+                Ok(count) => Some(count),
+                Err(e) => {
+                    error!("Failed to add noqa to {}: {e}", path.to_string_lossy());
+                    None
+                }
+            }
+        })
+        .sum();
+
+    let duration = start.elapsed();
+    debug!("Added noqa to files in: {:?}", duration);
+
+    Ok(modifications)
+}
+
+/// Automatically format a collection of files.
+pub fn autoformat(
+    files: &[PathBuf],
+    pyproject_strategy: &PyprojectDiscovery,
+    file_strategy: &FileDiscovery,
+    overrides: &Overrides,
+) -> Result<usize> {
+    // Collect all the files to format.
+    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);
+
+    let start = Instant::now();
+    let modifications = par_iter(&paths)
+        .flatten()
+        .filter_map(|entry| {
+            let path = entry.path();
+            let settings = resolver.resolve(path, pyproject_strategy);
+            match autoformat_path(path, settings) {
+                Ok(()) => Some(()),
+                Err(e) => {
+                    error!("Failed to autoformat {}: {e}", path.to_string_lossy());
+                    None
+                }
+            }
+        })
+        .count();
+
+    let duration = start.elapsed();
+    debug!("Auto-formatted files in: {:?}", duration);
+
+    Ok(modifications)
+}

 /// Print the user-facing configuration settings.
 pub fn show_settings(
-    configuration: &Configuration,
-    project_root: Option<&PathBuf>,
-    pyproject: Option<&PathBuf>,
-) {
-    println!("Resolved configuration: {configuration:#?}");
-    println!("Found project root at: {project_root:?}");
-    println!("Found pyproject.toml at: {pyproject:?}");
+    files: &[PathBuf],
+    pyproject_strategy: &PyprojectDiscovery,
+    file_strategy: &FileDiscovery,
+    overrides: &Overrides,
+) -> Result<()> {
+    // Collect all files in the hierarchy.
+    let (paths, resolver) =
+        resolver::python_files_in_path(files, pyproject_strategy, file_strategy, overrides)?;
+
+    // Print the list of files.
+    let Some(entry) = paths
+        .iter()
+        .flatten()
+        .sorted_by(|a, b| a.path().cmp(b.path())).next() else {
+        bail!("No files found under the given path");
+    };
+    let path = entry.path();
+    let settings = resolver.resolve(path, pyproject_strategy);
+    println!("Resolved settings for: {path:?}");
+    println!("{settings:#?}");
+
+    Ok(())
 }

 /// Show the list of files to be checked based on current settings.
-pub fn show_files(files: &[PathBuf], settings: &Settings) {
-    let mut entries: Vec<DirEntry> = files
+pub fn show_files(
+    files: &[PathBuf],
+    pyproject_strategy: &PyprojectDiscovery,
+    file_strategy: &FileDiscovery,
+    overrides: &Overrides,
+) -> Result<()> {
+    // Collect all files in the hierarchy.
+    let (paths, _resolver) =
+        resolver::python_files_in_path(files, pyproject_strategy, file_strategy, overrides)?;
+
+    // Print the list of files.
+    for entry in paths
        .iter()
-        .flat_map(|path| iter_python_files(path, &settings.exclude, &settings.extend_exclude))
        .flatten()
-        .collect();
-    entries.sort_by(|a, b| a.path().cmp(b.path()));
-    for entry in entries {
+        .sorted_by(|a, b| a.path().cmp(b.path()))
+    {
        println!("{}", entry.path().to_string_lossy());
    }
+
+    Ok(())
 }

 #[derive(Serialize)]
@@ -41,7 +243,7 @@ struct Explanation<'a> {
 }

 /// Explain a `CheckCode` to the user.
-pub fn explain(code: &CheckCode, format: SerializationFormat) -> Result<()> {
+pub fn explain(code: &CheckCode, format: &SerializationFormat) -> Result<()> {
    match format {
        SerializationFormat::Text | SerializationFormat::Grouped => {
            println!(
--- a/src/flake8_annotations/snapshots/ruff__flake8_annotationstestsallow_overload.snap
+++ b/src/flake8_annotations/snapshots/ruff__flake8_annotationstestsallow_overload.snap
@@ -8,7 +8,7 @@ expression: checks
    row: 29
    column: 4
  end_location:
-    row: 35
-    column: 0
+    row: 30
+    column: 16
  fix: ~

--- a/src/flake8_annotations/snapshots/ruff__flake8_annotationstestsdefaults.snap
+++ b/src/flake8_annotations/snapshots/ruff__flake8_annotationstestsdefaults.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 4
    column: 0
  end_location:
-    row: 9
-    column: 0
+    row: 5
+    column: 8
  fix: ~
 - kind:
    MissingTypeFunctionArgument: a
@@ -35,8 +35,8 @@ expression: checks
    row: 9
    column: 0
  end_location:
-    row: 14
-    column: 0
+    row: 10
+    column: 8
  fix: ~
 - kind:
    MissingTypeFunctionArgument: b
@@ -62,8 +62,8 @@ expression: checks
    row: 19
    column: 0
  end_location:
-    row: 24
-    column: 0
+    row: 20
+    column: 8
  fix: ~
 - kind:
    MissingReturnTypePublicFunction: foo
@@ -71,8 +71,8 @@ expression: checks
    row: 24
    column: 0
  end_location:
-    row: 29
-    column: 0
+    row: 25
+    column: 8
  fix: ~
 - kind:
    DynamicallyTypedExpression: a
--- a/src/flake8_annotations/snapshots/ruff__flake8_annotationstestsmypy_init_return.snap
+++ b/src/flake8_annotations/snapshots/ruff__flake8_annotationstestsmypy_init_return.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 5
    column: 4
  end_location:
-    row: 10
-    column: 0
+    row: 6
+    column: 11
  fix: ~
 - kind:
    MissingReturnTypeMagicMethod: __init__
@@ -17,8 +17,8 @@ expression: checks
    row: 11
    column: 4
  end_location:
-    row: 16
-    column: 0
+    row: 12
+    column: 11
  fix: ~
 - kind:
    MissingReturnTypePrivateFunction: __init__
@@ -26,7 +26,7 @@ expression: checks
    row: 40
    column: 0
  end_location:
-    row: 42
-    column: 0
+    row: 41
+    column: 7
  fix: ~

--- a/src/flake8_annotations/snapshots/ruff__flake8_annotationstestssuppress_none_returning.snap
+++ b/src/flake8_annotations/snapshots/ruff__flake8_annotationstestssuppress_none_returning.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 45
    column: 0
  end_location:
-    row: 50
-    column: 0
+    row: 46
+    column: 15
  fix: ~
 - kind:
    MissingReturnTypePublicFunction: foo
@@ -17,7 +17,7 @@ expression: checks
    row: 50
    column: 0
  end_location:
-    row: 56
-    column: 0
+    row: 55
+    column: 14
  fix: ~

--- a/src/flake8_bugbear/plugins/setattr_with_constant.rs
+++ b/src/flake8_bugbear/plugins/setattr_with_constant.rs
@@ -56,16 +56,23 @@ pub fn setattr_with_constant(checker: &mut Checker, expr: &Expr, func: &Expr, ar
    if KWLIST.contains(&name.as_str()) {
        return;
    }
-    let mut check = Check::new(CheckKind::SetAttrWithConstant, Range::from_located(expr));
-    if checker.patch(check.kind.code()) {
-        match assignment(obj, name, value) {
-            Ok(content) => check.amend(Fix::replacement(
-                content,
-                expr.location,
-                expr.end_location.unwrap(),
-            )),
-            Err(e) => error!("Failed to fix invalid comparison: {e}"),
-        };
+    // We can only replace a `setattr` call (which is an `Expr`) with an assignment
+    // (which is a `Stmt`) if the `Expr` is already being used as a `Stmt`
+    // (i.e., it's directly within an `StmtKind::Expr`).
+    if let StmtKind::Expr { value: child } = &checker.current_parent().0.node {
+        if expr == child.as_ref() {
+            let mut check = Check::new(CheckKind::SetAttrWithConstant, Range::from_located(expr));
+            if checker.patch(check.kind.code()) {
+                match assignment(obj, name, value) {
+                    Ok(content) => check.amend(Fix::replacement(
+                        content,
+                        expr.location,
+                        expr.end_location.unwrap(),
+                    )),
+                    Err(e) => error!("Failed to fix invalid comparison: {e}"),
+                };
+            }
+            checker.add_check(check);
+        }
    }
-    checker.add_check(check);
 }
--- a/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB009_B009_B010.py.snap
+++ b/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB009_B009_B010.py.snap
@@ -77,4 +77,19 @@ expression: checks
    end_location:
      row: 22
      column: 31
+- kind: GetAttrWithConstant
+  location:
+    row: 23
+    column: 3
+  end_location:
+    row: 23
+    column: 20
+  fix:
+    content: x.bar
+    location:
+      row: 23
+      column: 3
+    end_location:
+      row: 23
+      column: 20

--- a/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB010_B009_B010.py.snap
+++ b/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB010_B009_B010.py.snap
@@ -4,77 +4,77 @@ expression: checks
 ---
 - kind: SetAttrWithConstant
  location:
-    row: 33
+    row: 37
    column: 0
  end_location:
-    row: 33
+    row: 37
    column: 25
  fix:
    content: foo.bar = None
    location:
-      row: 33
+      row: 37
      column: 0
    end_location:
-      row: 33
+      row: 37
      column: 25
 - kind: SetAttrWithConstant
  location:
-    row: 34
+    row: 38
    column: 0
  end_location:
-    row: 34
+    row: 38
    column: 29
  fix:
    content: foo._123abc = None
    location:
-      row: 34
+      row: 38
      column: 0
    end_location:
-      row: 34
+      row: 38
      column: 29
 - kind: SetAttrWithConstant
  location:
-    row: 35
+    row: 39
    column: 0
  end_location:
-    row: 35
+    row: 39
    column: 28
  fix:
    content: foo.abc123 = None
    location:
-      row: 35
+      row: 39
      column: 0
    end_location:
-      row: 35
+      row: 39
      column: 28
 - kind: SetAttrWithConstant
  location:
-    row: 36
+    row: 40
    column: 0
  end_location:
-    row: 36
+    row: 40
    column: 29
  fix:
    content: foo.abc123 = None
    location:
-      row: 36
+      row: 40
      column: 0
    end_location:
-      row: 36
+      row: 40
      column: 29
 - kind: SetAttrWithConstant
  location:
-    row: 37
+    row: 41
    column: 0
  end_location:
-    row: 37
+    row: 41
    column: 30
  fix:
    content: foo.bar.baz = None
    location:
-      row: 37
+      row: 41
      column: 0
    end_location:
-      row: 37
+      row: 41
      column: 30

--- a/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB017_B017.py.snap
+++ b/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB017_B017.py.snap
@@ -7,7 +7,7 @@ expression: checks
    row: 22
    column: 8
  end_location:
-    row: 25
-    column: 4
+    row: 23
+    column: 42
  fix: ~

--- a/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB024_B024.py.snap
+++ b/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB024_B024.py.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 17
    column: 0
  end_location:
-    row: 22
-    column: 0
+    row: 19
+    column: 13
  fix: ~
 - kind:
    AbstractBaseClassWithoutAbstractMethod: MetaBase_1
@@ -17,8 +17,8 @@ expression: checks
    row: 58
    column: 0
  end_location:
-    row: 63
-    column: 0
+    row: 60
+    column: 13
  fix: ~
 - kind:
    AbstractBaseClassWithoutAbstractMethod: abc_Base_1
@@ -26,8 +26,8 @@ expression: checks
    row: 69
    column: 0
  end_location:
-    row: 74
-    column: 0
+    row: 71
+    column: 13
  fix: ~
 - kind:
    AbstractBaseClassWithoutAbstractMethod: abc_Base_2
@@ -35,8 +35,8 @@ expression: checks
    row: 74
    column: 0
  end_location:
-    row: 79
-    column: 0
+    row: 76
+    column: 13
  fix: ~
 - kind:
    AbstractBaseClassWithoutAbstractMethod: notabc_Base_1
@@ -44,8 +44,8 @@ expression: checks
    row: 79
    column: 0
  end_location:
-    row: 84
-    column: 0
+    row: 81
+    column: 13
  fix: ~
 - kind:
    AbstractBaseClassWithoutAbstractMethod: abc_set_class_variable_4
@@ -53,7 +53,7 @@ expression: checks
    row: 128
    column: 0
  end_location:
-    row: 130
-    column: 0
+    row: 129
+    column: 7
  fix: ~

--- a/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB025_B025.py.snap
+++ b/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB025_B025.py.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 15
    column: 0
  end_location:
-    row: 22
-    column: 0
+    row: 20
+    column: 9
  fix: ~
 - kind:
    DuplicateTryBlockException: pickle.PickleError
@@ -17,8 +17,8 @@ expression: checks
    row: 22
    column: 0
  end_location:
-    row: 31
-    column: 0
+    row: 29
+    column: 9
  fix: ~
 - kind:
    DuplicateTryBlockException: TypeError
@@ -26,8 +26,8 @@ expression: checks
    row: 31
    column: 0
  end_location:
-    row: 39
-    column: 0
+    row: 38
+    column: 9
  fix: ~
 - kind:
    DuplicateTryBlockException: ValueError
@@ -35,7 +35,7 @@ expression: checks
    row: 31
    column: 0
  end_location:
-    row: 39
-    column: 0
+    row: 38
+    column: 9
  fix: ~

--- a/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB027_B027.py.snap
+++ b/src/flake8_bugbear/snapshots/ruff__flake8_bugbeartestsB027_B027.py.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 12
    column: 4
  end_location:
-    row: 15
-    column: 4
+    row: 13
+    column: 11
  fix: ~
 - kind:
    EmptyMethodWithoutAbstractDecorator: AbstractClass
@@ -17,8 +17,8 @@ expression: checks
    row: 15
    column: 4
  end_location:
-    row: 18
-    column: 4
+    row: 16
+    column: 12
  fix: ~
 - kind:
    EmptyMethodWithoutAbstractDecorator: AbstractClass
@@ -26,8 +26,8 @@ expression: checks
    row: 18
    column: 4
  end_location:
-    row: 22
-    column: 4
+    row: 20
+    column: 11
  fix: ~
 - kind:
    EmptyMethodWithoutAbstractDecorator: AbstractClass
@@ -35,7 +35,7 @@ expression: checks
    row: 22
    column: 4
  end_location:
-    row: 29
-    column: 4
+    row: 27
+    column: 12
  fix: ~

--- a/src/flake8_builtins/checks.rs
+++ b/src/flake8_builtins/checks.rs
@@ -1,10 +1,16 @@
+use rustpython_ast::Located;
+
 use crate::ast::types::Range;
 use crate::checks::{Check, CheckKind};
 use crate::flake8_builtins::types::ShadowingType;
 use crate::python::builtins::BUILTINS;

 /// Check builtin name shadowing.
-pub fn builtin_shadowing(name: &str, location: Range, node_type: ShadowingType) -> Option<Check> {
+pub fn builtin_shadowing<T>(
+    name: &str,
+    located: &Located<T>,
+    node_type: ShadowingType,
+) -> Option<Check> {
    if BUILTINS.contains(&name) {
        Some(Check::new(
            match node_type {
@@ -12,7 +18,7 @@ pub fn builtin_shadowing(name: &str, location: Range, node_type: ShadowingType)
                ShadowingType::Argument => CheckKind::BuiltinArgumentShadowing(name.to_string()),
                ShadowingType::Attribute => CheckKind::BuiltinAttributeShadowing(name.to_string()),
            },
-            location,
+            Range::from_located(located),
        ))
    } else {
        None
--- a/src/flake8_builtins/snapshots/ruff__flake8_builtinstestsA001_A001.py.snap
+++ b/src/flake8_builtins/snapshots/ruff__flake8_builtinstestsA001_A001.py.snap
@@ -89,8 +89,8 @@ expression: checks
    row: 10
    column: 0
  end_location:
-    row: 13
-    column: 0
+    row: 11
+    column: 8
  fix: ~
 - kind:
    BuiltinVariableShadowing: slice
@@ -98,8 +98,8 @@ expression: checks
    row: 13
    column: 0
  end_location:
-    row: 16
-    column: 0
+    row: 14
+    column: 8
  fix: ~
 - kind:
    BuiltinVariableShadowing: ValueError
@@ -107,8 +107,8 @@ expression: checks
    row: 18
    column: 0
  end_location:
-    row: 21
-    column: 0
+    row: 19
+    column: 7
  fix: ~
 - kind:
    BuiltinVariableShadowing: memoryview
--- a/src/flake8_builtins/snapshots/ruff__flake8_builtinstestsA003_A003.py.snap
+++ b/src/flake8_builtins/snapshots/ruff__flake8_builtinstestsA003_A003.py.snap
@@ -17,7 +17,7 @@ expression: checks
    row: 7
    column: 4
  end_location:
-    row: 9
-    column: 0
+    row: 8
+    column: 12
  fix: ~

--- a/src/flake8_errmsg/checks.rs
+++ b/src/flake8_errmsg/checks.rs
@@ -0,0 +1,46 @@
+use rustpython_ast::{Constant, Expr, ExprKind};
+
+use crate::ast::types::Range;
+use crate::checks::{Check, CheckKind};
+
+pub fn check_string_in_exception(exc: &Expr, max_string_length: usize) -> Vec<Check> {
+    let mut checks = vec![];
+
+    if let ExprKind::Call { args, .. } = &exc.node {
+        if let Some(first) = args.first() {
+            match &first.node {
+                // Check for string literals
+                ExprKind::Constant {
+                    value: Constant::Str(string),
+                    ..
+                } => {
+                    if string.len() > max_string_length {
+                        checks.push(Check::new(
+                            CheckKind::RawStringInException,
+                            Range::from_located(first),
+                        ));
+                    }
+                }
+                // Check for f-strings
+                ExprKind::JoinedStr { .. } => checks.push(Check::new(
+                    CheckKind::FStringInException,
+                    Range::from_located(first),
+                )),
+                // Check for .format() calls
+                ExprKind::Call { func, .. } => {
+                    if let ExprKind::Attribute { value, attr, .. } = &func.node {
+                        if attr == "format" && matches!(value.node, ExprKind::Constant { .. }) {
+                            checks.push(Check::new(
+                                CheckKind::DotFormatInException,
+                                Range::from_located(first),
+                            ));
+                        }
+                    }
+                }
+                _ => {}
+            }
+        }
+    }
+
+    checks
+}
--- a/src/flake8_errmsg/mod.rs
+++ b/src/flake8_errmsg/mod.rs
@@ -0,0 +1,50 @@
+pub mod checks;
+pub mod settings;
+
+#[cfg(test)]
+mod tests {
+    use std::path::Path;
+
+    use anyhow::Result;
+
+    use crate::checks::CheckCode;
+    use crate::linter::test_path;
+    use crate::{flake8_errmsg, settings};
+
+    #[test]
+    fn defaults() -> Result<()> {
+        let mut checks = test_path(
+            Path::new("./resources/test/fixtures/flake8_errmsg/EM.py"),
+            &settings::Settings::for_rules(vec![
+                CheckCode::EM101,
+                CheckCode::EM102,
+                CheckCode::EM103,
+            ]),
+            false,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!("defaults", checks);
+        Ok(())
+    }
+
+    #[test]
+    fn custom() -> Result<()> {
+        let mut checks = test_path(
+            Path::new("./resources/test/fixtures/flake8_errmsg/EM.py"),
+            &settings::Settings {
+                flake8_errmsg: flake8_errmsg::settings::Settings {
+                    max_string_length: 20,
+                },
+                ..settings::Settings::for_rules(vec![
+                    CheckCode::EM101,
+                    CheckCode::EM102,
+                    CheckCode::EM103,
+                ])
+            },
+            false,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!("custom", checks);
+        Ok(())
+    }
+}
--- a/src/flake8_errmsg/settings.rs
+++ b/src/flake8_errmsg/settings.rs
@@ -0,0 +1,32 @@
+//! Settings for the `flake8-errmsg` plugin.
+
+use ruff_macros::ConfigurationOptions;
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Default, ConfigurationOptions)]
+#[serde(deny_unknown_fields, rename_all = "kebab-case")]
+pub struct Options {
+    #[option(
+        doc = r#"
+            Maximum string length for string literals in exception messages.
+        "#,
+        default = "0",
+        value_type = "usize",
+        example = "max-string-length = 20"
+    )]
+    pub max_string_length: Option<usize>,
+}
+
+#[derive(Debug, Default, Hash)]
+pub struct Settings {
+    pub max_string_length: usize,
+}
+
+impl Settings {
+    #[allow(clippy::needless_pass_by_value)]
+    pub fn from_options(options: Options) -> Self {
+        Self {
+            max_string_length: options.max_string_length.unwrap_or_default(),
+        }
+    }
+}
--- a/src/flake8_errmsg/snapshots/ruff__flake8_errmsgtestscustom.snap
+++ b/src/flake8_errmsg/snapshots/ruff__flake8_errmsgtestscustom.snap
@@ -0,0 +1,29 @@
+---
+source: src/flake8_errmsg/mod.rs
+expression: checks
+---
+- kind: RawStringInException
+  location:
+    row: 5
+    column: 23
+  end_location:
+    row: 5
+    column: 53
+  fix: ~
+- kind: FStringInException
+  location:
+    row: 10
+    column: 23
+  end_location:
+    row: 10
+    column: 56
+  fix: ~
+- kind: DotFormatInException
+  location:
+    row: 14
+    column: 23
+  end_location:
+    row: 14
+    column: 81
+  fix: ~
+
--- a/src/flake8_errmsg/snapshots/ruff__flake8_errmsgtestsdefaults.snap
+++ b/src/flake8_errmsg/snapshots/ruff__flake8_errmsgtestsdefaults.snap
@@ -0,0 +1,29 @@
+---
+source: src/flake8_errmsg/mod.rs
+expression: checks
+---
+- kind: RawStringInException
+  location:
+    row: 5
+    column: 23
+  end_location:
+    row: 5
+    column: 53
+  fix: ~
+- kind: FStringInException
+  location:
+    row: 10
+    column: 23
+  end_location:
+    row: 10
+    column: 56
+  fix: ~
+- kind: DotFormatInException
+  location:
+    row: 14
+    column: 23
+  end_location:
+    row: 14
+    column: 81
+  fix: ~
+
--- a/src/flake8_print/plugins/print_call.rs
+++ b/src/flake8_print/plugins/print_call.rs
@@ -23,7 +23,12 @@ pub fn print_call(checker: &mut Checker, expr: &Expr, func: &Expr) {
        let defined_in = checker.current_grandparent();
        if matches!(defined_by.0.node, StmtKind::Expr { .. }) {
            let deleted: Vec<&Stmt> = checker.deletions.iter().map(|node| node.0).collect();
-            match helpers::remove_stmt(defined_by.0, defined_in.map(|node| node.0), &deleted) {
+            match helpers::delete_stmt(
+                defined_by.0,
+                defined_in.map(|node| node.0),
+                &deleted,
+                checker.locator,
+            ) {
                Ok(fix) => {
                    if fix.content.is_empty() || fix.content == "pass" {
                        checker.deletions.insert(defined_by.clone());
--- a/src/flake8_return/snapshots/ruff__flake8_returntestsRET503_RET503.py.snap
+++ b/src/flake8_return/snapshots/ruff__flake8_returntestsRET503_RET503.py.snap
@@ -7,8 +7,8 @@ expression: checks
    row: 7
    column: 4
  end_location:
-    row: 12
-    column: 0
+    row: 8
+    column: 16
  fix: ~
 - kind: ImplicitReturn
  location:
@@ -45,8 +45,8 @@ expression: checks
    row: 29
    column: 8
  end_location:
-    row: 34
-    column: 0
+    row: 30
+    column: 20
  fix: ~
 - kind: ImplicitReturn
  location:
--- a/src/flake8_return/snapshots/ruff__flake8_returntestsRET505_RET505.py.snap
+++ b/src/flake8_return/snapshots/ruff__flake8_returntestsRET505_RET505.py.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 5
    column: 4
  end_location:
-    row: 16
-    column: 0
+    row: 13
+    column: 16
  fix: ~
 - kind:
    SuperfluousElseReturn: Elif
@@ -17,8 +17,8 @@ expression: checks
    row: 17
    column: 4
  end_location:
-    row: 27
-    column: 4
+    row: 26
+    column: 13
  fix: ~
 - kind:
    SuperfluousElseReturn: Elif
@@ -26,8 +26,8 @@ expression: checks
    row: 38
    column: 4
  end_location:
-    row: 49
-    column: 0
+    row: 46
+    column: 16
  fix: ~
 - kind:
    SuperfluousElseReturn: Else
@@ -35,8 +35,8 @@ expression: checks
    row: 50
    column: 4
  end_location:
-    row: 58
-    column: 0
+    row: 55
+    column: 16
  fix: ~
 - kind:
    SuperfluousElseReturn: Else
@@ -44,8 +44,8 @@ expression: checks
    row: 61
    column: 8
  end_location:
-    row: 67
-    column: 4
+    row: 66
+    column: 20
  fix: ~
 - kind:
    SuperfluousElseReturn: Else
@@ -53,8 +53,8 @@ expression: checks
    row: 73
    column: 4
  end_location:
-    row: 81
-    column: 4
+    row: 80
+    column: 13
  fix: ~
 - kind:
    SuperfluousElseReturn: Else
@@ -62,8 +62,8 @@ expression: checks
    row: 86
    column: 8
  end_location:
-    row: 91
-    column: 4
+    row: 90
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseReturn: Else
@@ -71,7 +71,7 @@ expression: checks
    row: 97
    column: 4
  end_location:
-    row: 109
-    column: 0
+    row: 103
+    column: 23
  fix: ~

--- a/src/flake8_return/snapshots/ruff__flake8_returntestsRET506_RET506.py.snap
+++ b/src/flake8_return/snapshots/ruff__flake8_returntestsRET506_RET506.py.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 5
    column: 4
  end_location:
-    row: 16
-    column: 0
+    row: 13
+    column: 26
  fix: ~
 - kind:
    SuperfluousElseRaise: Elif
@@ -17,8 +17,8 @@ expression: checks
    row: 17
    column: 4
  end_location:
-    row: 27
-    column: 4
+    row: 26
+    column: 13
  fix: ~
 - kind:
    SuperfluousElseRaise: Else
@@ -26,8 +26,8 @@ expression: checks
    row: 31
    column: 4
  end_location:
-    row: 39
-    column: 0
+    row: 36
+    column: 26
  fix: ~
 - kind:
    SuperfluousElseRaise: Else
@@ -35,8 +35,8 @@ expression: checks
    row: 42
    column: 8
  end_location:
-    row: 48
-    column: 4
+    row: 47
+    column: 30
  fix: ~
 - kind:
    SuperfluousElseRaise: Else
@@ -44,8 +44,8 @@ expression: checks
    row: 54
    column: 4
  end_location:
-    row: 62
-    column: 4
+    row: 61
+    column: 13
  fix: ~
 - kind:
    SuperfluousElseRaise: Else
@@ -53,8 +53,8 @@ expression: checks
    row: 67
    column: 8
  end_location:
-    row: 72
-    column: 4
+    row: 71
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseRaise: Else
@@ -62,7 +62,7 @@ expression: checks
    row: 78
    column: 4
  end_location:
-    row: 90
-    column: 0
+    row: 84
+    column: 33
  fix: ~

--- a/src/flake8_return/snapshots/ruff__flake8_returntestsRET507_RET507.py.snap
+++ b/src/flake8_return/snapshots/ruff__flake8_returntestsRET507_RET507.py.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 6
    column: 8
  end_location:
-    row: 14
-    column: 0
+    row: 11
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseContinue: Elif
@@ -17,8 +17,8 @@ expression: checks
    row: 16
    column: 8
  end_location:
-    row: 26
-    column: 8
+    row: 25
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseContinue: Else
@@ -26,8 +26,8 @@ expression: checks
    row: 34
    column: 8
  end_location:
-    row: 40
-    column: 0
+    row: 37
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseContinue: Else
@@ -35,8 +35,8 @@ expression: checks
    row: 44
    column: 12
  end_location:
-    row: 50
-    column: 8
+    row: 49
+    column: 24
  fix: ~
 - kind:
    SuperfluousElseContinue: Else
@@ -44,8 +44,8 @@ expression: checks
    row: 57
    column: 8
  end_location:
-    row: 65
-    column: 8
+    row: 64
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseContinue: Else
@@ -53,8 +53,8 @@ expression: checks
    row: 71
    column: 12
  end_location:
-    row: 76
-    column: 8
+    row: 75
+    column: 21
  fix: ~
 - kind:
    SuperfluousElseContinue: Else
@@ -62,7 +62,7 @@ expression: checks
    row: 83
    column: 8
  end_location:
-    row: 92
-    column: 0
+    row: 89
+    column: 24
  fix: ~

--- a/src/flake8_return/snapshots/ruff__flake8_returntestsRET508_RET508.py.snap
+++ b/src/flake8_return/snapshots/ruff__flake8_returntestsRET508_RET508.py.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 6
    column: 8
  end_location:
-    row: 14
-    column: 0
+    row: 11
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseBreak: Elif
@@ -17,8 +17,8 @@ expression: checks
    row: 16
    column: 8
  end_location:
-    row: 26
-    column: 8
+    row: 25
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseBreak: Else
@@ -26,8 +26,8 @@ expression: checks
    row: 31
    column: 8
  end_location:
-    row: 37
-    column: 0
+    row: 34
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseBreak: Else
@@ -35,8 +35,8 @@ expression: checks
    row: 41
    column: 12
  end_location:
-    row: 47
-    column: 8
+    row: 46
+    column: 21
  fix: ~
 - kind:
    SuperfluousElseBreak: Else
@@ -44,8 +44,8 @@ expression: checks
    row: 54
    column: 8
  end_location:
-    row: 62
-    column: 8
+    row: 61
+    column: 17
  fix: ~
 - kind:
    SuperfluousElseBreak: Else
@@ -53,8 +53,8 @@ expression: checks
    row: 68
    column: 12
  end_location:
-    row: 73
-    column: 8
+    row: 72
+    column: 21
  fix: ~
 - kind:
    SuperfluousElseBreak: Else
@@ -62,7 +62,7 @@ expression: checks
    row: 80
    column: 8
  end_location:
-    row: 92
-    column: 0
+    row: 86
+    column: 21
  fix: ~

--- a/src/fs.rs
+++ b/src/fs.rs
@@ -5,15 +5,13 @@ use std::path::{Path, PathBuf};

 use anyhow::{anyhow, Result};
 use globset::GlobMatcher;
-use log::debug;
 use path_absolutize::{path_dedot, Absolutize};
 use rustc_hash::FxHashSet;
-use walkdir::{DirEntry, WalkDir};

 use crate::checks::CheckCode;

 /// Extract the absolute path and basename (as strings) from a Path.
-fn extract_path_names(path: &Path) -> Result<(&str, &str)> {
+pub fn extract_path_names(path: &Path) -> Result<(&str, &str)> {
    let file_path = path
        .to_str()
        .ok_or_else(|| anyhow!("Unable to parse filename: {:?}", path))?;
@@ -25,62 +23,7 @@ fn extract_path_names(path: &Path) -> Result<(&str, &str)> {
    Ok((file_path, file_basename))
 }

-fn is_excluded(file_path: &str, file_basename: &str, exclude: &globset::GlobSet) -> bool {
-    exclude.is_match(file_path) || exclude.is_match(file_basename)
-}
-
-fn is_included(path: &Path) -> bool {
-    let file_name = path.to_string_lossy();
-    file_name.ends_with(".py") || file_name.ends_with(".pyi")
-}
-
-pub fn iter_python_files<'a>(
-    path: &'a Path,
-    exclude: &'a globset::GlobSet,
-    extend_exclude: &'a globset::GlobSet,
-) -> impl Iterator<Item = Result<DirEntry, walkdir::Error>> + 'a {
-    // Run some checks over the provided patterns, to enable optimizations below.
-    let has_exclude = !exclude.is_empty();
-    let has_extend_exclude = !extend_exclude.is_empty();
-
-    WalkDir::new(normalize_path(path))
-        .into_iter()
-        .filter_entry(move |entry| {
-            if !has_exclude && !has_extend_exclude {
-                return true;
-            }
-
-            let path = entry.path();
-            match extract_path_names(path) {
-                Ok((file_path, file_basename)) => {
-                    if has_exclude && is_excluded(file_path, file_basename, exclude) {
-                        debug!("Ignored path via `exclude`: {:?}", path);
-                        false
-                    } else if has_extend_exclude
-                        && is_excluded(file_path, file_basename, extend_exclude)
-                    {
-                        debug!("Ignored path via `extend-exclude`: {:?}", path);
-                        false
-                    } else {
-                        true
-                    }
-                }
-                Err(e) => {
-                    debug!("Ignored path due to error in parsing: {:?}: {}", path, e);
-                    true
-                }
-            }
-        })
-        .filter(|entry| {
-            entry.as_ref().map_or(true, |entry| {
-                (entry.depth() == 0 || is_included(entry.path()))
-                    && !entry.file_type().is_dir()
-                    && !(entry.file_type().is_symlink() && entry.path().is_dir())
-            })
-        })
-}
-
-/// Create tree set with codes matching the pattern/code pairs.
+/// Create a set with codes matching the pattern/code pairs.
 pub(crate) fn ignores_from_path<'a>(
    path: &Path,
    pattern_code_pairs: &'a [(GlobMatcher, GlobMatcher, FxHashSet<CheckCode>)],
@@ -128,114 +71,3 @@ pub(crate) fn read_file(path: &Path) -> Result<String> {
    buf_reader.read_to_string(&mut contents)?;
    Ok(contents)
 }
-
-#[cfg(test)]
-mod tests {
-    use std::path::{Path, PathBuf};
-
-    use anyhow::Result;
-    use globset::GlobSet;
-    use path_absolutize::Absolutize;
-
-    use crate::fs::{extract_path_names, is_excluded, is_included};
-    use crate::settings::types::FilePattern;
-
-    #[test]
-    fn inclusions() {
-        let path = Path::new("foo/bar/baz.py").absolutize().unwrap();
-        assert!(is_included(&path));
-
-        let path = Path::new("foo/bar/baz.pyi").absolutize().unwrap();
-        assert!(is_included(&path));
-
-        let path = Path::new("foo/bar/baz.js").absolutize().unwrap();
-        assert!(!is_included(&path));
-
-        let path = Path::new("foo/bar/baz").absolutize().unwrap();
-        assert!(!is_included(&path));
-    }
-
-    fn make_exclusion(file_pattern: FilePattern, project_root: Option<&PathBuf>) -> GlobSet {
-        let mut builder = globset::GlobSetBuilder::new();
-        file_pattern.add_to(&mut builder, project_root).unwrap();
-        builder.build().unwrap()
-    }
-
-    #[test]
-    fn exclusions() -> Result<()> {
-        let project_root = Path::new("/tmp/");
-
-        let path = Path::new("foo").absolutize_from(project_root).unwrap();
-        let exclude = FilePattern::User("foo".to_string());
-        let (file_path, file_basename) = extract_path_names(&path)?;
-        assert!(is_excluded(
-            file_path,
-            file_basename,
-            &make_exclusion(exclude, Some(&project_root.to_path_buf()))
-        ));
-
-        let path = Path::new("foo/bar").absolutize_from(project_root).unwrap();
-        let exclude = FilePattern::User("bar".to_string());
-        let (file_path, file_basename) = extract_path_names(&path)?;
-        assert!(is_excluded(
-            file_path,
-            file_basename,
-            &make_exclusion(exclude, Some(&project_root.to_path_buf()))
-        ));
-
-        let path = Path::new("foo/bar/baz.py")
-            .absolutize_from(project_root)
-            .unwrap();
-        let exclude = FilePattern::User("baz.py".to_string());
-        let (file_path, file_basename) = extract_path_names(&path)?;
-        assert!(is_excluded(
-            file_path,
-            file_basename,
-            &make_exclusion(exclude, Some(&project_root.to_path_buf()))
-        ));
-
-        let path = Path::new("foo/bar").absolutize_from(project_root).unwrap();
-        let exclude = FilePattern::User("foo/bar".to_string());
-        let (file_path, file_basename) = extract_path_names(&path)?;
-        assert!(is_excluded(
-            file_path,
-            file_basename,
-            &make_exclusion(exclude, Some(&project_root.to_path_buf()))
-        ));
-
-        let path = Path::new("foo/bar/baz.py")
-            .absolutize_from(project_root)
-            .unwrap();
-        let exclude = FilePattern::User("foo/bar/baz.py".to_string());
-        let (file_path, file_basename) = extract_path_names(&path)?;
-        assert!(is_excluded(
-            file_path,
-            file_basename,
-            &make_exclusion(exclude, Some(&project_root.to_path_buf()))
-        ));
-
-        let path = Path::new("foo/bar/baz.py")
-            .absolutize_from(project_root)
-            .unwrap();
-        let exclude = FilePattern::User("foo/bar/*.py".to_string());
-        let (file_path, file_basename) = extract_path_names(&path)?;
-        assert!(is_excluded(
-            file_path,
-            file_basename,
-            &make_exclusion(exclude, Some(&project_root.to_path_buf()))
-        ));
-
-        let path = Path::new("foo/bar/baz.py")
-            .absolutize_from(project_root)
-            .unwrap();
-        let exclude = FilePattern::User("baz".to_string());
-        let (file_path, file_basename) = extract_path_names(&path)?;
-        assert!(!is_excluded(
-            file_path,
-            file_basename,
-            &make_exclusion(exclude, Some(&project_root.to_path_buf()))
-        ));
-
-        Ok(())
-    }
-}
--- a/src/isort/plugins.rs
+++ b/src/isort/plugins.rs
@@ -1,7 +1,9 @@
 use rustpython_ast::{Location, Stmt};
 use textwrap::{dedent, indent};

-use crate::ast::helpers::{count_trailing_lines, match_leading_content, match_trailing_content};
+use crate::ast::helpers::{
+    count_trailing_lines, followed_by_multi_statement_line, preceded_by_multi_statement_line,
+};
 use crate::ast::types::Range;
 use crate::ast::whitespace::leading_space;
 use crate::autofix::Fix;
@@ -39,6 +41,14 @@ pub fn check_imports(

    let range = extract_range(&block.imports);

+    // Special-cases: there's leading or trailing content in the import block. These
+    // are too hard to get right, and relatively rare, so flag but don't fix.
+    if preceded_by_multi_statement_line(block.imports.first().unwrap(), locator)
+        || followed_by_multi_statement_line(block.imports.last().unwrap(), locator)
+    {
+        return Some(Check::new(CheckKind::UnsortedImports, range));
+    }
+
    // Extract comments. Take care to grab any inline comments from the last line.
    let comments = comments::collect_comments(
        &Range {
@@ -48,9 +58,6 @@ pub fn check_imports(
        locator,
    );

-    // Special-cases: there's leading or trailing content in the import block.
-    let has_leading_content = match_leading_content(block.imports.first().unwrap(), locator);
-    let has_trailing_content = match_trailing_content(block.imports.last().unwrap(), locator);
    let num_trailing_lines = if block.trailer.is_none() {
        0
    } else {
@@ -70,46 +77,23 @@ pub fn check_imports(
        settings.isort.force_wrap_aliases,
    );

-    if has_leading_content || has_trailing_content {
+    // Expand the span the entire range, including leading and trailing space.
+    let range = Range {
+        location: Location::new(range.location.row(), 0),
+        end_location: Location::new(range.end_location.row() + 1 + num_trailing_lines, 0),
+    };
+    let actual = dedent(&locator.slice_source_code_range(&range));
+    if actual == expected {
+        None
+    } else {
        let mut check = Check::new(CheckKind::UnsortedImports, range);
        if autofix && settings.fixable.contains(check.kind.code()) {
-            let mut content = String::new();
-            if has_leading_content {
-                content.push('\n');
-            }
-            content.push_str(&indent(&expected, indentation));
            check.amend(Fix::replacement(
-                content,
-                // Preserve leading prefix (but put the imports on a new line).
-                if has_leading_content {
-                    range.location
-                } else {
-                    Location::new(range.location.row(), 0)
-                },
-                // TODO(charlie): Preserve trailing suffixes. Right now, we strip them.
-                Location::new(range.end_location.row() + 1 + num_trailing_lines, 0),
+                indent(&expected, indentation),
+                range.location,
+                range.end_location,
            ));
        }
        Some(check)
-    } else {
-        // Expand the span the entire range, including leading and trailing space.
-        let range = Range {
-            location: Location::new(range.location.row(), 0),
-            end_location: Location::new(range.end_location.row() + 1 + num_trailing_lines, 0),
-        };
-        let actual = dedent(&locator.slice_source_code_range(&range));
-        if actual == expected {
-            None
-        } else {
-            let mut check = Check::new(CheckKind::UnsortedImports, range);
-            if autofix && settings.fixable.contains(check.kind.code()) {
-                check.amend(Fix::replacement(
-                    indent(&expected, indentation),
-                    range.location,
-                    range.end_location,
-                ));
-            }
-            Some(check)
-        }
    }
 }
--- a/src/isort/snapshots/ruffisorttests__leading_prefix.py.snap
+++ b/src/isort/snapshots/ruffisorttests__leading_prefix.py.snap
@@ -9,14 +9,7 @@ expression: checks
  end_location:
    row: 2
    column: 9
-  fix:
-    content: "\nimport os\nimport sys\n\n"
-    location:
-      row: 1
-      column: 7
-    end_location:
-      row: 4
-      column: 0
+  fix: ~
 - kind: UnsortedImports
  location:
    row: 5
@@ -24,12 +17,21 @@ expression: checks
  end_location:
    row: 6
    column: 13
-  fix:
-    content: "\n    import os\n    import sys\n"
-    location:
-      row: 5
-      column: 11
-    end_location:
-      row: 7
-      column: 0
+  fix: ~
+- kind: UnsortedImports
+  location:
+    row: 10
+    column: 8
+  end_location:
+    row: 10
+    column: 17
+  fix: ~
+- kind: UnsortedImports
+  location:
+    row: 13
+    column: 0
+  end_location:
+    row: 13
+    column: 9
+  fix: ~

--- a/src/isort/snapshots/ruffisorttests__trailing_suffix.py.snap
+++ b/src/isort/snapshots/ruffisorttests__trailing_suffix.py.snap
@@ -9,14 +9,7 @@ expression: checks
  end_location:
    row: 2
    column: 9
-  fix:
-    content: "import os\nimport sys\n\n"
-    location:
-      row: 1
-      column: 0
-    end_location:
-      row: 4
-      column: 0
+  fix: ~
 - kind: UnsortedImports
  location:
    row: 5
@@ -24,12 +17,5 @@ expression: checks
  end_location:
    row: 6
    column: 13
-  fix:
-    content: "    import os\n    import sys\n"
-    location:
-      row: 5
-      column: 0
-    end_location:
-      row: 7
-      column: 0
+  fix: ~

--- a/src/iterators.rs
+++ b/src/iterators.rs
@@ -0,0 +1,16 @@
+#[cfg(not(target_family = "wasm"))]
+use rayon::prelude::*;
+
+/// Shim that calls `par_iter` except for wasm because there's no wasm support
+/// in rayon yet (there is a shim to be used for the web, but it requires js
+/// cooperation) Unfortunately, `ParallelIterator` does not implement `Iterator`
+/// so the signatures diverge
+#[cfg(not(target_family = "wasm"))]
+pub fn par_iter<T: Sync>(iterable: &[T]) -> impl ParallelIterator<Item = &T> {
+    iterable.par_iter()
+}
+
+#[cfg(target_family = "wasm")]
+pub fn par_iter<T: Sync>(iterable: &[T]) -> impl Iterator<Item = &T> {
+    iterable.iter()
+}
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -14,13 +14,14 @@
 use std::path::Path;

 use anyhow::Result;
-use log::debug;
+use path_absolutize::path_dedot;
 use rustpython_helpers::tokenize;
 use rustpython_parser::lexer::LexResult;
 use settings::{pyproject, Settings};

 use crate::checks::Check;
 use crate::linter::check_path;
+use crate::resolver::Relativity;
 use crate::settings::configuration::Configuration;
 use crate::source_code_locator::SourceCodeLocator;

@@ -49,6 +50,7 @@ pub mod flake8_bugbear;
 mod flake8_builtins;
 mod flake8_comprehensions;
 mod flake8_debugger;
+pub mod flake8_errmsg;
 mod flake8_import_conventions;
 mod flake8_print;
 pub mod flake8_quotes;
@@ -58,12 +60,14 @@ pub mod flake8_tidy_imports;
 mod flake8_unused_arguments;
 pub mod fs;
 mod isort;
+pub mod iterators;
 mod lex;
 pub mod linter;
 pub mod logging;
 pub mod mccabe;
 pub mod message;
 mod noqa;
+mod pandas_vet;
 pub mod pep8_naming;
 pub mod printer;
 mod pycodestyle;
@@ -73,6 +77,7 @@ mod pygrep_hooks;
 mod pylint;
 mod python;
 mod pyupgrade;
+pub mod resolver;
 mod ruff;
 mod rustpython_helpers;
 pub mod settings;
@@ -82,24 +87,24 @@ pub mod updates;
 mod vendored;
 pub mod visibility;

+/// Load the relevant `Settings` for a given `Path`.
+fn resolve(path: &Path) -> Result<Settings> {
+    if let Some(pyproject) = pyproject::find_pyproject_toml(path)? {
+        // First priority: `pyproject.toml` in the current `Path`.
+        resolver::resolve_settings(&pyproject, &Relativity::Parent, None)
+    } else if let Some(pyproject) = pyproject::find_user_pyproject_toml() {
+        // Second priority: user-specific `pyproject.toml`.
+        resolver::resolve_settings(&pyproject, &Relativity::Cwd, None)
+    } else {
+        // Fallback: default settings.
+        Settings::from_configuration(Configuration::default(), &path_dedot::CWD)
+    }
+}
+
 /// Run Ruff over Python source code directly.
 pub fn check(path: &Path, contents: &str, autofix: bool) -> Result<Vec<Check>> {
-    // Find the project root and pyproject.toml.
-    let project_root = pyproject::find_project_root(&[path.to_path_buf()]);
-    match &project_root {
-        Some(path) => debug!("Found project root at: {:?}", path),
-        None => debug!("Unable to identify project root; assuming current directory..."),
-    };
-    let pyproject = pyproject::find_pyproject_toml(project_root.as_ref());
-    match &pyproject {
-        Some(path) => debug!("Found pyproject.toml at: {:?}", path),
-        None => debug!("Unable to find pyproject.toml; using default settings..."),
-    };
-
-    let settings = Settings::from_configuration(
-        Configuration::from_pyproject(pyproject.as_ref(), project_root.as_ref())?,
-        project_root.as_ref(),
-    )?;
+    // Load the relevant `Settings` for the given `Path`.
+    let settings = resolve(path)?;

    // Tokenize once.
    let tokens: Vec<LexResult> = tokenize(contents);
--- a/src/linter.rs
+++ b/src/linter.rs
@@ -83,7 +83,15 @@ pub(crate) fn check_path(
        match rustpython_helpers::parse_program_tokens(tokens, "<filename>") {
            Ok(python_ast) => {
                if use_ast {
-                    checks.extend(check_ast(&python_ast, locator, settings, autofix, path));
+                    checks.extend(check_ast(
+                        &python_ast,
+                        locator,
+                        &directives.noqa_line_for,
+                        settings,
+                        autofix,
+                        ignore_noqa,
+                        path,
+                    ));
                }
                if use_imports {
                    checks.extend(check_imports(
@@ -211,7 +219,7 @@ pub fn add_noqa_to_path(path: &Path, settings: &Settings) -> Result<usize> {
 }

 /// Apply autoformatting to the source code at the given `Path`.
-pub fn autoformat_path(path: &Path) -> Result<()> {
+pub fn autoformat_path(path: &Path, _settings: &Settings) -> Result<()> {
    // Read the file from disk.
    let contents = fs::read_file(path)?;

--- a/src/main.rs
+++ b/src/main.rs
@@ -11,190 +11,64 @@
    clippy::too_many_lines
 )]

-use std::io::{self, Read};
+use std::io::{self};
 use std::path::{Path, PathBuf};
 use std::process::ExitCode;
 use std::sync::mpsc::channel;
-use std::time::Instant;

 use ::ruff::autofix::fixer;
-use ::ruff::checks::{CheckCode, CheckKind};
 use ::ruff::cli::{extract_log_level, Cli};
-use ::ruff::fs::iter_python_files;
-use ::ruff::linter::{add_noqa_to_path, autoformat_path, lint_path, lint_stdin, Diagnostics};
 use ::ruff::logging::{set_up_logging, LogLevel};
-use ::ruff::message::Message;
 use ::ruff::printer::Printer;
+use ::ruff::resolver::PyprojectDiscovery;
 use ::ruff::settings::configuration::Configuration;
 use ::ruff::settings::types::SerializationFormat;
 use ::ruff::settings::{pyproject, Settings};
 #[cfg(feature = "update-informer")]
 use ::ruff::updates;
-use ::ruff::{cache, commands, fs};
+use ::ruff::{cache, commands};
 use anyhow::Result;
 use clap::{CommandFactory, Parser};
 use colored::Colorize;
-use log::{debug, error};
 use notify::{recommended_watcher, RecursiveMode, Watcher};
-#[cfg(not(target_family = "wasm"))]
-use rayon::prelude::*;
-use rustpython_ast::Location;
-use walkdir::DirEntry;
+use path_absolutize::path_dedot;
+use ruff::cli::Overrides;
+use ruff::resolver::{resolve_settings, FileDiscovery, Relativity};

-/// Shim that calls `par_iter` except for wasm because there's no wasm support
-/// in rayon yet (there is a shim to be used for the web, but it requires js
-/// cooperation) Unfortunately, `ParallelIterator` does not implement `Iterator`
-/// so the signatures diverge
-#[cfg(not(target_family = "wasm"))]
-fn par_iter<T: Sync>(iterable: &Vec<T>) -> impl ParallelIterator<Item = &T> {
-    iterable.par_iter()
-}
-
-#[cfg(target_family = "wasm")]
-fn par_iter<T: Sync>(iterable: &Vec<T>) -> impl Iterator<Item = &T> {
-    iterable.iter()
-}
-
-fn read_from_stdin() -> Result<String> {
-    let mut buffer = String::new();
-    io::stdin().lock().read_to_string(&mut buffer)?;
-    Ok(buffer)
-}
-
-fn run_once_stdin(
-    settings: &Settings,
-    filename: &Path,
-    autofix: &fixer::Mode,
-) -> Result<Diagnostics> {
-    let stdin = read_from_stdin()?;
-    let mut diagnostics = lint_stdin(filename, &stdin, settings, autofix)?;
-    diagnostics.messages.sort_unstable();
-    Ok(diagnostics)
-}
-
-fn run_once(
-    files: &[PathBuf],
-    settings: &Settings,
-    cache: bool,
-    autofix: &fixer::Mode,
-) -> Diagnostics {
-    // Collect all the files to check.
-    let start = Instant::now();
-    let paths: Vec<Result<DirEntry, walkdir::Error>> = files
-        .iter()
-        .flat_map(|path| iter_python_files(path, &settings.exclude, &settings.extend_exclude))
-        .collect();
-    let duration = start.elapsed();
-    debug!("Identified files to lint in: {:?}", duration);
-
-    let start = Instant::now();
-    let mut diagnostics: Diagnostics = par_iter(&paths)
-        .map(|entry| {
-            match entry {
-                Ok(entry) => {
-                    let path = entry.path();
-                    lint_path(path, settings, &cache.into(), autofix)
-                        .map_err(|e| (Some(path.to_owned()), e.to_string()))
-                }
-                Err(e) => Err((
-                    e.path().map(Path::to_owned),
-                    e.io_error()
-                        .map_or_else(|| e.to_string(), io::Error::to_string),
-                )),
-            }
-            .unwrap_or_else(|(path, message)| {
-                if let Some(path) = path {
-                    if settings.enabled.contains(&CheckCode::E902) {
-                        Diagnostics::new(vec![Message {
-                            kind: CheckKind::IOError(message),
-                            location: Location::default(),
-                            end_location: Location::default(),
-                            fix: None,
-                            filename: path.to_string_lossy().to_string(),
-                            source: None,
-                        }])
-                    } else {
-                        error!("Failed to check {}: {message}", path.to_string_lossy());
-                        Diagnostics::default()
-                    }
-                } else {
-                    error!("{message}");
-                    Diagnostics::default()
-                }
-            })
-        })
-        .reduce(Diagnostics::default, |mut acc, item| {
-            acc += item;
-            acc
-        });
-
-    diagnostics.messages.sort_unstable();
-    let duration = start.elapsed();
-    debug!("Checked files in: {:?}", duration);
-
-    diagnostics
-}
-
-fn add_noqa(files: &[PathBuf], settings: &Settings) -> usize {
-    // Collect all the files to check.
-    let start = Instant::now();
-    let paths: Vec<DirEntry> = files
-        .iter()
-        .flat_map(|path| iter_python_files(path, &settings.exclude, &settings.extend_exclude))
-        .flatten()
-        .collect();
-    let duration = start.elapsed();
-    debug!("Identified files to lint in: {:?}", duration);
-
-    let start = Instant::now();
-    let modifications: usize = par_iter(&paths)
-        .filter_map(|entry| {
-            let path = entry.path();
-            match add_noqa_to_path(path, settings) {
-                Ok(count) => Some(count),
-                Err(e) => {
-                    error!("Failed to add noqa to {}: {e}", path.to_string_lossy());
-                    None
-                }
-            }
-        })
-        .sum();
-
-    let duration = start.elapsed();
-    debug!("Added noqa to files in: {:?}", duration);
-
-    modifications
-}
-
-fn autoformat(files: &[PathBuf], settings: &Settings) -> usize {
-    // Collect all the files to format.
-    let start = Instant::now();
-    let paths: Vec<DirEntry> = files
-        .iter()
-        .flat_map(|path| iter_python_files(path, &settings.exclude, &settings.extend_exclude))
-        .flatten()
-        .collect();
-    let duration = start.elapsed();
-    debug!("Identified files to lint in: {:?}", duration);
-
-    let start = Instant::now();
-    let modifications = par_iter(&paths)
-        .filter_map(|entry| {
-            let path = entry.path();
-            match autoformat_path(path) {
-                Ok(()) => Some(()),
-                Err(e) => {
-                    error!("Failed to autoformat {}: {e}", path.to_string_lossy());
-                    None
-                }
-            }
-        })
-        .count();
-
-    let duration = start.elapsed();
-    debug!("Auto-formatted files in: {:?}", duration);
-
-    modifications
+/// Resolve the relevant settings strategy and defaults for the current
+/// invocation.
+fn resolve(config: Option<PathBuf>, overrides: &Overrides) -> Result<PyprojectDiscovery> {
+    if let Some(pyproject) = config {
+        // First priority: the user specified a `pyproject.toml` file. Use that
+        // `pyproject.toml` for _all_ configuration, and resolve paths relative to the
+        // current working directory. (This matches ESLint's behavior.)
+        let settings = resolve_settings(&pyproject, &Relativity::Cwd, Some(overrides))?;
+        Ok(PyprojectDiscovery::Fixed(settings))
+    } else if let Some(pyproject) = pyproject::find_pyproject_toml(path_dedot::CWD.as_path())? {
+        // Second priority: find a `pyproject.toml` file in the current working path,
+        // and resolve all paths relative to that directory. (With
+        // `Strategy::Hierarchical`, we'll end up finding the "closest" `pyproject.toml`
+        // file for every Python file later on, so these act as the "default" settings.)
+        let settings = resolve_settings(&pyproject, &Relativity::Parent, Some(overrides))?;
+        Ok(PyprojectDiscovery::Hierarchical(settings))
+    } else if let Some(pyproject) = pyproject::find_user_pyproject_toml() {
+        // Third priority: find a user-specific `pyproject.toml`, but resolve all paths
+        // relative the current working directory. (With `Strategy::Hierarchical`, we'll
+        // end up the "closest" `pyproject.toml` file for every Python file later on, so
+        // these act as the "default" settings.)
+        let settings = resolve_settings(&pyproject, &Relativity::Cwd, Some(overrides))?;
+        Ok(PyprojectDiscovery::Hierarchical(settings))
+    } else {
+        // Fallback: load Ruff's default settings, and resolve all paths relative to the
+        // current working directory. (With `Strategy::Hierarchical`, we'll end up the
+        // "closest" `pyproject.toml` file for every Python file later on, so these act
+        // as the "default" settings.)
+        let mut config = Configuration::default();
+        // Apply command-line options that override defaults.
+        config.apply(overrides.clone());
+        let settings = Settings::from_configuration(config, &path_dedot::CWD)?;
+        Ok(PyprojectDiscovery::Hierarchical(settings))
+    }
 }

 fn inner_main() -> Result<ExitCode> {
@@ -203,63 +77,48 @@ fn inner_main() -> Result<ExitCode> {
    let log_level = extract_log_level(&cli);
    set_up_logging(&log_level)?;

-    if let Some(shell) = cli.generate_shell_completion {
-        shell.generate(&mut Cli::command(), &mut std::io::stdout());
-        return Ok(ExitCode::SUCCESS);
-    }
-
-    // Find the project root and pyproject.toml.
-    let config: Option<PathBuf> = cli.config;
-    let project_root = config.as_ref().map_or_else(
-        || pyproject::find_project_root(&cli.files),
-        |config| config.parent().map(fs::normalize_path),
-    );
-    let pyproject = config.or_else(|| pyproject::find_pyproject_toml(project_root.as_ref()));
-
-    // Reconcile configuration from pyproject.toml and command-line arguments.
-    let mut configuration =
-        Configuration::from_pyproject(pyproject.as_ref(), project_root.as_ref())?;
-    configuration.merge(overrides);
-
    if cli.show_settings && cli.show_files {
-        eprintln!("Error: specify --show-settings or show-files (not both).");
-        return Ok(ExitCode::FAILURE);
+        anyhow::bail!("specify --show-settings or show-files (not both)")
    }
-    if cli.show_settings {
-        commands::show_settings(&configuration, project_root.as_ref(), pyproject.as_ref());
+    if let Some(shell) = cli.generate_shell_completion {
+        shell.generate(&mut Cli::command(), &mut io::stdout());
        return Ok(ExitCode::SUCCESS);
    }

-    // TODO(charlie): Included in `pyproject.toml`, but not inherited.
-    let fix = if configuration.fix {
+    // Construct the "default" settings. These are used when no `pyproject.toml`
+    // files are present, or files are injected from outside of the hierarchy.
+    let pyproject_strategy = resolve(cli.config, &overrides)?;
+
+    // Extract options that are included in `Settings`, but only apply at the top
+    // level.
+    let file_strategy = FileDiscovery {
+        respect_gitignore: match &pyproject_strategy {
+            PyprojectDiscovery::Fixed(settings) => settings.respect_gitignore,
+            PyprojectDiscovery::Hierarchical(settings) => settings.respect_gitignore,
+        },
+    };
+    let (fix, format) = match &pyproject_strategy {
+        PyprojectDiscovery::Fixed(settings) => (settings.fix, settings.format),
+        PyprojectDiscovery::Hierarchical(settings) => (settings.fix, settings.format),
+    };
+    let autofix = if fix {
        fixer::Mode::Apply
-    } else if matches!(configuration.format, SerializationFormat::Json) {
+    } else if matches!(format, SerializationFormat::Json) {
        fixer::Mode::Generate
    } else {
        fixer::Mode::None
    };
-    let format = configuration.format;
-
-    let settings = Settings::from_configuration(configuration, project_root.as_ref())?;
-
-    // Now that we've inferred the appropriate log level, add some debug
-    // information.
-    match &project_root {
-        Some(path) => debug!("Found project root at: {:?}", path),
-        None => debug!("Unable to identify project root; assuming current directory..."),
-    };
-    match &pyproject {
-        Some(path) => debug!("Found pyproject.toml at: {:?}", path),
-        None => debug!("Unable to find pyproject.toml; using default settings..."),
-    };

    if let Some(code) = cli.explain {
-        commands::explain(&code, format)?;
+        commands::explain(&code, &format)?;
+        return Ok(ExitCode::SUCCESS);
+    }
+    if cli.show_settings {
+        commands::show_settings(&cli.files, &pyproject_strategy, &file_strategy, &overrides)?;
        return Ok(ExitCode::SUCCESS);
    }
-
    if cli.show_files {
-        commands::show_files(&cli.files, &settings);
+        commands::show_files(&cli.files, &pyproject_strategy, &file_strategy, &overrides)?;
        return Ok(ExitCode::SUCCESS);
    }

@@ -272,7 +131,7 @@ fn inner_main() -> Result<ExitCode> {

    let printer = Printer::new(&format, &log_level);
    if cli.watch {
-        if matches!(fix, fixer::Mode::Generate | fixer::Mode::Apply) {
+        if matches!(autofix, fixer::Mode::Generate | fixer::Mode::Apply) {
            eprintln!("Warning: --fix is not enabled in watch mode.");
        }
        if cli.add_noqa {
@@ -289,7 +148,14 @@ fn inner_main() -> Result<ExitCode> {
        printer.clear_screen()?;
        printer.write_to_user("Starting linter in watch mode...\n");

-        let messages = run_once(&cli.files, &settings, cache_enabled, &fixer::Mode::None);
+        let messages = commands::run(
+            &cli.files,
+            &pyproject_strategy,
+            &file_strategy,
+            &overrides,
+            cache_enabled,
+            &fixer::Mode::None,
+        )?;
        printer.write_continuously(&messages)?;

        // Configure the file watcher.
@@ -301,32 +167,40 @@ fn inner_main() -> Result<ExitCode> {

        loop {
            match rx.recv() {
-                Ok(e) => {
-                    let paths = e?.paths;
-                    let py_changed = paths.iter().any(|p| {
-                        p.extension()
-                            .map(|ext| ext.eq_ignore_ascii_case("py"))
+                Ok(event) => {
+                    let paths = event?.paths;
+                    let py_changed = paths.iter().any(|path| {
+                        path.extension()
+                            .map(|ext| ext == "py" || ext == "pyi")
                            .unwrap_or_default()
                    });
                    if py_changed {
                        printer.clear_screen()?;
                        printer.write_to_user("File change detected...\n");

-                        let messages =
-                            run_once(&cli.files, &settings, cache_enabled, &fixer::Mode::None);
+                        let messages = commands::run(
+                            &cli.files,
+                            &pyproject_strategy,
+                            &file_strategy,
+                            &overrides,
+                            cache_enabled,
+                            &fixer::Mode::None,
+                        )?;
                        printer.write_continuously(&messages)?;
                    }
                }
-                Err(e) => return Err(e.into()),
+                Err(err) => return Err(err.into()),
            }
        }
    } else if cli.add_noqa {
-        let modifications = add_noqa(&cli.files, &settings);
+        let modifications =
+            commands::add_noqa(&cli.files, &pyproject_strategy, &file_strategy, &overrides)?;
        if modifications > 0 && log_level >= LogLevel::Default {
            println!("Added {modifications} noqa directives.");
        }
    } else if cli.autoformat {
-        let modifications = autoformat(&cli.files, &settings);
+        let modifications =
+            commands::autoformat(&cli.files, &pyproject_strategy, &file_strategy, &overrides)?;
        if modifications > 0 && log_level >= LogLevel::Default {
            println!("Formatted {modifications} files.");
        }
@@ -337,16 +211,23 @@ fn inner_main() -> Result<ExitCode> {
        let diagnostics = if is_stdin {
            let filename = cli.stdin_filename.unwrap_or_else(|| "-".to_string());
            let path = Path::new(&filename);
-            run_once_stdin(&settings, path, &fix)?
+            commands::run_stdin(&pyproject_strategy, path, &autofix)?
        } else {
-            run_once(&cli.files, &settings, cache_enabled, &fix)
+            commands::run(
+                &cli.files,
+                &pyproject_strategy,
+                &file_strategy,
+                &overrides,
+                cache_enabled,
+                &autofix,
+            )?
        };

        // Always try to print violations (the printer itself may suppress output),
        // unless we're writing fixes via stdin (in which case, the transformed
        // source code goes to stdout).
-        if !(is_stdin && matches!(fix, fixer::Mode::Apply)) {
-            printer.write_once(&diagnostics, &fix)?;
+        if !(is_stdin && matches!(autofix, fixer::Mode::Apply)) {
+            printer.write_once(&diagnostics, &autofix)?;
        }

        // Check for updates if we're in a non-silent log level.
--- a/src/mccabe/checks.rs
+++ b/src/mccabe/checks.rs
@@ -1,7 +1,8 @@
 use rustpython_ast::{ExcepthandlerKind, ExprKind, Stmt, StmtKind};

-use crate::ast::types::Range;
+use crate::ast::helpers::identifier_range;
 use crate::checks::{Check, CheckKind};
+use crate::source_code_locator::SourceCodeLocator;

 fn get_complexity_number(stmts: &[Stmt]) -> usize {
    let mut complexity = 0;
@@ -59,12 +60,13 @@ pub fn function_is_too_complex(
    name: &str,
    body: &[Stmt],
    max_complexity: usize,
+    locator: &SourceCodeLocator,
 ) -> Option<Check> {
    let complexity = get_complexity_number(body) + 1;
    if complexity > max_complexity {
        Some(Check::new(
            CheckKind::FunctionIsTooComplex(name.to_string(), complexity),
-            Range::from_located(stmt),
+            identifier_range(stmt, locator),
        ))
    } else {
        None
--- a/src/mccabe/snapshots/ruffmccabetests__max_complexity_0.snap
+++ b/src/mccabe/snapshots/ruffmccabetests__max_complexity_0.snap
@@ -8,10 +8,10 @@ expression: checks
      - 1
  location:
    row: 2
-    column: 0
+    column: 4
  end_location:
-    row: 7
-    column: 0
+    row: 2
+    column: 11
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -19,10 +19,10 @@ expression: checks
      - 1
  location:
    row: 7
-    column: 0
+    column: 4
  end_location:
-    row: 12
-    column: 0
+    row: 7
+    column: 21
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -30,10 +30,10 @@ expression: checks
      - 1
  location:
    row: 12
-    column: 0
+    column: 4
  end_location:
-    row: 19
-    column: 0
+    row: 12
+    column: 14
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -41,10 +41,10 @@ expression: checks
      - 3
  location:
    row: 19
-    column: 0
+    column: 4
  end_location:
-    row: 29
-    column: 0
+    row: 19
+    column: 26
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -52,10 +52,10 @@ expression: checks
      - 3
  location:
    row: 29
-    column: 0
+    column: 4
  end_location:
-    row: 40
-    column: 0
+    row: 29
+    column: 14
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -63,10 +63,10 @@ expression: checks
      - 2
  location:
    row: 40
-    column: 0
+    column: 4
  end_location:
-    row: 46
-    column: 0
+    row: 40
+    column: 12
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -74,10 +74,10 @@ expression: checks
      - 2
  location:
    row: 46
-    column: 0
+    column: 4
  end_location:
-    row: 54
-    column: 0
+    row: 46
+    column: 12
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -85,10 +85,10 @@ expression: checks
      - 2
  location:
    row: 54
-    column: 0
+    column: 4
  end_location:
-    row: 62
-    column: 0
+    row: 54
+    column: 13
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -96,10 +96,10 @@ expression: checks
      - 3
  location:
    row: 62
-    column: 0
+    column: 4
  end_location:
-    row: 73
-    column: 0
+    row: 62
+    column: 20
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -107,10 +107,10 @@ expression: checks
      - 2
  location:
    row: 63
-    column: 4
+    column: 8
  end_location:
-    row: 69
-    column: 4
+    row: 63
+    column: 9
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -118,10 +118,10 @@ expression: checks
      - 1
  location:
    row: 64
-    column: 8
+    column: 12
  end_location:
-    row: 67
-    column: 8
+    row: 64
+    column: 13
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -129,10 +129,10 @@ expression: checks
      - 4
  location:
    row: 73
-    column: 0
+    column: 4
  end_location:
-    row: 85
-    column: 0
+    row: 73
+    column: 12
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -140,10 +140,10 @@ expression: checks
      - 3
  location:
    row: 85
-    column: 0
+    column: 4
  end_location:
-    row: 96
-    column: 0
+    row: 85
+    column: 22
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -151,10 +151,10 @@ expression: checks
      - 3
  location:
    row: 96
-    column: 0
+    column: 10
  end_location:
-    row: 107
-    column: 0
+    row: 96
+    column: 16
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -162,10 +162,10 @@ expression: checks
      - 1
  location:
    row: 107
-    column: 0
+    column: 4
  end_location:
-    row: 112
-    column: 0
+    row: 107
+    column: 20
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -173,10 +173,10 @@ expression: checks
      - 9
  location:
    row: 113
-    column: 4
+    column: 8
  end_location:
-    row: 139
-    column: 0
+    row: 113
+    column: 14
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -184,10 +184,10 @@ expression: checks
      - 1
  location:
    row: 118
-    column: 12
+    column: 16
  end_location:
-    row: 121
-    column: 12
+    row: 118
+    column: 17
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -195,10 +195,10 @@ expression: checks
      - 2
  location:
    row: 121
-    column: 12
+    column: 16
  end_location:
-    row: 125
-    column: 8
+    row: 121
+    column: 17
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -206,10 +206,10 @@ expression: checks
      - 1
  location:
    row: 126
-    column: 12
+    column: 16
  end_location:
-    row: 129
-    column: 12
+    row: 126
+    column: 17
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -217,10 +217,10 @@ expression: checks
      - 1
  location:
    row: 129
-    column: 12
+    column: 16
  end_location:
-    row: 132
-    column: 12
+    row: 129
+    column: 21
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -228,10 +228,10 @@ expression: checks
      - 1
  location:
    row: 132
-    column: 12
+    column: 16
  end_location:
-    row: 135
-    column: 12
+    row: 132
+    column: 20
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -239,9 +239,9 @@ expression: checks
      - 1
  location:
    row: 135
-    column: 12
+    column: 16
  end_location:
-    row: 138
-    column: 8
+    row: 135
+    column: 25
  fix: ~

--- a/src/mccabe/snapshots/ruffmccabetests__max_complexity_3.snap
+++ b/src/mccabe/snapshots/ruffmccabetests__max_complexity_3.snap
@@ -8,10 +8,10 @@ expression: checks
      - 4
  location:
    row: 73
-    column: 0
+    column: 4
  end_location:
-    row: 85
-    column: 0
+    row: 73
+    column: 12
  fix: ~
 - kind:
    FunctionIsTooComplex:
@@ -19,9 +19,9 @@ expression: checks
      - 9
  location:
    row: 113
-    column: 4
+    column: 8
  end_location:
-    row: 139
-    column: 0
+    row: 113
+    column: 14
  fix: ~

--- a/src/pandas_vet/checks.rs
+++ b/src/pandas_vet/checks.rs
@@ -0,0 +1,61 @@
+use rustpython_ast::{Constant, Expr, ExprKind, Keyword};
+
+use crate::ast::types::Range;
+use crate::checks::{Check, CheckKind};
+
+/// PDV002
+pub fn inplace_argument(keywords: &[Keyword]) -> Option<Check> {
+    for keyword in keywords {
+        let arg = keyword.node.arg.as_ref()?;
+
+        if arg == "inplace" {
+            let is_true_literal = match &keyword.node.value.node {
+                ExprKind::Constant {
+                    value: Constant::Bool(boolean),
+                    ..
+                } => *boolean,
+                _ => false,
+            };
+            if is_true_literal {
+                return Some(Check::new(
+                    CheckKind::UseOfInplaceArgument,
+                    Range::from_located(keyword),
+                ));
+            }
+        }
+    }
+    None
+}
+
+/// PDV015
+pub fn use_of_pd_merge(func: &Expr) -> Option<Check> {
+    if let ExprKind::Attribute { attr, value, .. } = &func.node {
+        if let ExprKind::Name { id, .. } = &value.node {
+            if id == "pd" && attr == "merge" {
+                return Some(Check::new(
+                    CheckKind::UseOfPdMerge,
+                    Range::from_located(func),
+                ));
+            }
+        }
+    }
+    None
+}
+
+/// PDV901
+pub fn assignment_to_df(targets: &[Expr]) -> Option<Check> {
+    if targets.len() != 1 {
+        return None;
+    }
+    let target = &targets[0];
+    let ExprKind::Name { id, .. } = &target.node else {
+        return None;
+    };
+    if id != "df" {
+        return None;
+    }
+    Some(Check::new(
+        CheckKind::DfIsABadVariableName,
+        Range::from_located(target),
+    ))
+}
--- a/src/pandas_vet/mod.rs
+++ b/src/pandas_vet/mod.rs
@@ -0,0 +1,109 @@
+pub mod checks;
+
+#[cfg(test)]
+mod tests {
+    use std::path::Path;
+
+    use anyhow::Result;
+    use rustpython_parser::lexer::LexResult;
+    use test_case::test_case;
+    use textwrap::dedent;
+
+    use crate::checks::CheckCode;
+    use crate::checks_gen::CheckCodePrefix;
+    use crate::linter::check_path;
+    use crate::source_code_locator::SourceCodeLocator;
+    use crate::{directives, rustpython_helpers, settings};
+
+    fn check_code(contents: &str, expected: &[CheckCode]) -> Result<()> {
+        let contents = dedent(contents);
+        let settings = settings::Settings::for_rules(CheckCodePrefix::PDV.codes());
+        let tokens: Vec<LexResult> = rustpython_helpers::tokenize(&contents);
+        let locator = SourceCodeLocator::new(&contents);
+        let directives = directives::extract_directives(
+            &tokens,
+            &locator,
+            directives::Flags::from_settings(&settings),
+        );
+        let mut checks = check_path(
+            Path::new("<filename>"),
+            &contents,
+            tokens,
+            &locator,
+            &directives,
+            &settings,
+            true,
+            false,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        let actual = checks
+            .iter()
+            .map(|check| check.kind.code().clone())
+            .collect::<Vec<_>>();
+        assert_eq!(actual, expected);
+        Ok(())
+    }
+
+    #[test_case("df.drop(['a'], axis=1, inplace=False)", &[]; "PDV002_pass")]
+    #[test_case("df.drop(['a'], axis=1, inplace=True)", &[CheckCode::PDV002]; "PDV002_fail")]
+    #[test_case("nas = pd.isna(val)", &[]; "PDV003_pass")]
+    #[test_case("nulls = pd.isnull(val)", &[CheckCode::PDV003]; "PDV003_fail")]
+    #[test_case("print('bah humbug')", &[]; "PDV003_allows_other_calls")]
+    #[test_case("not_nas = pd.notna(val)", &[]; "PDV004_pass")]
+    #[test_case("not_nulls = pd.notnull(val)", &[CheckCode::PDV004]; "PDV004_fail")]
+    #[test_case("new_df = df.loc['d':, 'A':'C']", &[]; "PDV007_pass_loc")]
+    #[test_case("new_df = df.iloc[[1, 3, 5], [1, 3]]", &[]; "PDV007_pass_iloc")]
+    #[test_case("s = df.ix[[0, 2], 'A']", &[CheckCode::PDV007]; "PDV007_fail")]
+    #[test_case("index = df.loc[:, ['B', 'A']]", &[]; "PDV008_pass")]
+    #[test_case("index = df.at[:, ['B', 'A']]", &[CheckCode::PDV008]; "PDV008_fail")]
+    #[test_case("index = df.iloc[:, 1:3]", &[]; "PDV009_pass")]
+    #[test_case("index = df.iat[:, 1:3]", &[CheckCode::PDV009]; "PDV009_fail")]
+    #[test_case(r#"table = df.pivot_table(
+        df,
+        values='D',
+        index=['A', 'B'],
+        columns=['C'],
+        aggfunc=np.sum,
+        fill_value=0
+    )
+    "#, &[]; "PDV010_pass")]
+    #[test_case(r#"table = pd.pivot(
+        df,
+        index='foo',
+        columns='bar',
+        values='baz'
+    )
+    "#, &[CheckCode::PDV010]; "PDV010_fail_pivot")]
+    #[test_case("result = df.to_array()", &[]; "PDV011_pass_to_array")]
+    #[test_case("result = df.array", &[]; "PDV011_pass_array")]
+    #[test_case("result = df.values", &[CheckCode::PDV011]; "PDV011_fail_values")]
+    // TODO: Check that the attribute access is NOT a method call
+    // #[test_case("result = {}.values()", &[]; "PDV011_pass_values_call")]
+    #[test_case("result = values", &[]; "PDV011_pass_node_name")]
+    #[test_case("employees = pd.read_csv(input_file)", &[]; "PDV012_pass_read_csv")]
+    #[test_case("employees = pd.read_table(input_file)", &[CheckCode::PDV012]; "PDV012_fail_read_table")]
+    #[test_case("employees = read_table", &[]; "PDV012_node_Name_pass")]
+    #[test_case(r#"table = df.melt(
+        id_vars='airline',
+        value_vars=['ATL', 'DEN', 'DFW'],
+        value_name='airline delay'
+        )
+    "#, &[]; "PDV013_pass")]
+    #[test_case("table = df.stack(level=-1, dropna=True)", &[CheckCode::PDV013]; "PDV013_fail_stack")]
+    #[test_case("df1.merge(df2)", &[]; "PD015_pass_merge_on_dataframe")]
+    #[test_case("df1.merge(df2, 'inner')", &[]; "PD015_pass_merge_on_dataframe_with_multiple_args")]
+    #[test_case("pd.merge(df1, df2)", &[CheckCode::PDV015]; "PD015_fail_merge_on_pandas_object")]
+    #[test_case(
+        "pd.to_datetime(timestamp * 10 ** 9).strftime('%Y-%m-%d %H:%M:%S.%f')",
+        &[];
+        "PD015_pass_other_pd_function"
+    )]
+    #[test_case("employees = pd.DataFrame(employee_dict)", &[]; "PDV901_pass_non_df")]
+    #[test_case("employees_df = pd.DataFrame(employee_dict)", &[]; "PDV901_pass_part_df")]
+    #[test_case("my_function(df=data)", &[]; "PDV901_pass_df_param")]
+    #[test_case("df = pd.DataFrame()", &[CheckCode::PDV901]; "PDV901_fail_df_var")]
+    fn test_pandas_vet(code: &str, expected: &[CheckCode]) -> Result<()> {
+        check_code(code, expected)?;
+        Ok(())
+    }
+}
--- a/src/pep8_naming/checks.rs
+++ b/src/pep8_naming/checks.rs
@@ -1,47 +1,53 @@
 use rustc_hash::{FxHashMap, FxHashSet};
-use rustpython_ast::{Arguments, Expr, ExprKind, Stmt};
+use rustpython_ast::{Arg, Arguments, Expr, ExprKind, Stmt};

 use crate::ast::function_type;
+use crate::ast::helpers::identifier_range;
 use crate::ast::types::{Range, Scope, ScopeKind};
 use crate::checks::{Check, CheckKind};
 use crate::pep8_naming::helpers;
 use crate::pep8_naming::settings::Settings;
 use crate::python::string::{self};
+use crate::source_code_locator::SourceCodeLocator;

 /// N801
-pub fn invalid_class_name(class_def: &Stmt, name: &str) -> Option<Check> {
+pub fn invalid_class_name(
+    class_def: &Stmt,
+    name: &str,
+    locator: &SourceCodeLocator,
+) -> Option<Check> {
    let stripped = name.strip_prefix('_').unwrap_or(name);
    if !stripped.chars().next().map_or(false, char::is_uppercase) || stripped.contains('_') {
        return Some(Check::new(
            CheckKind::InvalidClassName(name.to_string()),
-            Range::from_located(class_def),
+            identifier_range(class_def, locator),
        ));
    }
    None
 }

 /// N802
-pub fn invalid_function_name(func_def: &Stmt, name: &str, settings: &Settings) -> Option<Check> {
-    if name.to_lowercase() != name
-        && !settings
-            .ignore_names
-            .iter()
-            .any(|ignore_name| ignore_name == name)
-    {
+pub fn invalid_function_name(
+    func_def: &Stmt,
+    name: &str,
+    ignore_names: &[String],
+    locator: &SourceCodeLocator,
+) -> Option<Check> {
+    if name.to_lowercase() != name && !ignore_names.iter().any(|ignore_name| ignore_name == name) {
        return Some(Check::new(
            CheckKind::InvalidFunctionName(name.to_string()),
-            Range::from_located(func_def),
+            identifier_range(func_def, locator),
        ));
    }
    None
 }

 /// N803
-pub fn invalid_argument_name(name: &str, location: Range) -> Option<Check> {
+pub fn invalid_argument_name(name: &str, arg: &Arg) -> Option<Check> {
    if name.to_lowercase() != name {
        return Some(Check::new(
            CheckKind::InvalidArgumentName(name.to_string()),
-            location,
+            Range::from_located(arg),
        ));
    }
    None
@@ -124,7 +130,12 @@ pub fn invalid_first_argument_name_for_method(
 }

 /// N807
-pub fn dunder_function_name(scope: &Scope, stmt: &Stmt, name: &str) -> Option<Check> {
+pub fn dunder_function_name(
+    scope: &Scope,
+    stmt: &Stmt,
+    name: &str,
+    locator: &SourceCodeLocator,
+) -> Option<Check> {
    if matches!(scope.kind, ScopeKind::Class(_)) {
        return None;
    }
@@ -138,7 +149,7 @@ pub fn dunder_function_name(scope: &Scope, stmt: &Stmt, name: &str) -> Option<Ch

    Some(Check::new(
        CheckKind::DunderFunctionName,
-        Range::from_located(stmt),
+        identifier_range(stmt, locator),
    ))
 }

@@ -147,11 +158,12 @@ pub fn constant_imported_as_non_constant(
    import_from: &Stmt,
    name: &str,
    asname: &str,
+    locator: &SourceCodeLocator,
 ) -> Option<Check> {
    if string::is_upper(name) && !string::is_upper(asname) {
        return Some(Check::new(
            CheckKind::ConstantImportedAsNonConstant(name.to_string(), asname.to_string()),
-            Range::from_located(import_from),
+            identifier_range(import_from, locator),
        ));
    }
    None
@@ -162,11 +174,12 @@ pub fn lowercase_imported_as_non_lowercase(
    import_from: &Stmt,
    name: &str,
    asname: &str,
+    locator: &SourceCodeLocator,
 ) -> Option<Check> {
    if !string::is_upper(name) && string::is_lower(name) && asname.to_lowercase() != asname {
        return Some(Check::new(
            CheckKind::LowercaseImportedAsNonLowercase(name.to_string(), asname.to_string()),
-            Range::from_located(import_from),
+            identifier_range(import_from, locator),
        ));
    }
    None
@@ -177,11 +190,12 @@ pub fn camelcase_imported_as_lowercase(
    import_from: &Stmt,
    name: &str,
    asname: &str,
+    locator: &SourceCodeLocator,
 ) -> Option<Check> {
    if helpers::is_camelcase(name) && string::is_lower(asname) {
        return Some(Check::new(
            CheckKind::CamelcaseImportedAsLowercase(name.to_string(), asname.to_string()),
-            Range::from_located(import_from),
+            identifier_range(import_from, locator),
        ));
    }
    None
@@ -192,6 +206,7 @@ pub fn camelcase_imported_as_constant(
    import_from: &Stmt,
    name: &str,
    asname: &str,
+    locator: &SourceCodeLocator,
 ) -> Option<Check> {
    if helpers::is_camelcase(name)
        && !string::is_lower(asname)
@@ -200,7 +215,7 @@ pub fn camelcase_imported_as_constant(
    {
        return Some(Check::new(
            CheckKind::CamelcaseImportedAsConstant(name.to_string(), asname.to_string()),
-            Range::from_located(import_from),
+            identifier_range(import_from, locator),
        ));
    }
    None
@@ -211,6 +226,7 @@ pub fn camelcase_imported_as_acronym(
    import_from: &Stmt,
    name: &str,
    asname: &str,
+    locator: &SourceCodeLocator,
 ) -> Option<Check> {
    if helpers::is_camelcase(name)
        && !string::is_lower(asname)
@@ -219,7 +235,7 @@ pub fn camelcase_imported_as_acronym(
    {
        return Some(Check::new(
            CheckKind::CamelcaseImportedAsAcronym(name.to_string(), asname.to_string()),
-            Range::from_located(import_from),
+            identifier_range(import_from, locator),
        ));
    }
    None
--- a/src/pep8_naming/snapshots/ruff__pep8_namingtestsN801_N801.py.snap
+++ b/src/pep8_naming/snapshots/ruff__pep8_namingtestsN801_N801.py.snap
@@ -6,45 +6,45 @@ expression: checks
    InvalidClassName: bad
  location:
    row: 1
-    column: 0
+    column: 6
  end_location:
-    row: 5
-    column: 0
+    row: 1
+    column: 9
  fix: ~
 - kind:
    InvalidClassName: _bad
  location:
    row: 5
-    column: 0
+    column: 6
  end_location:
-    row: 9
-    column: 0
+    row: 5
+    column: 10
  fix: ~
 - kind:
    InvalidClassName: bad_class
  location:
    row: 9
-    column: 0
+    column: 6
  end_location:
-    row: 13
-    column: 0
+    row: 9
+    column: 15
  fix: ~
 - kind:
    InvalidClassName: Bad_Class
  location:
    row: 13
-    column: 0
+    column: 6
  end_location:
-    row: 17
-    column: 0
+    row: 13
+    column: 15
  fix: ~
 - kind:
    InvalidClassName: BAD_CLASS
  location:
    row: 17
-    column: 0
+    column: 6
  end_location:
-    row: 21
-    column: 0
+    row: 17
+    column: 15
  fix: ~

--- a/src/pep8_naming/snapshots/ruff__pep8_namingtestsN802_N802.py.snap
+++ b/src/pep8_naming/snapshots/ruff__pep8_namingtestsN802_N802.py.snap
@@ -6,45 +6,45 @@ expression: checks
    InvalidFunctionName: Bad
  location:
    row: 4
-    column: 0
+    column: 4
  end_location:
-    row: 8
-    column: 0
+    row: 4
+    column: 7
  fix: ~
 - kind:
    InvalidFunctionName: _Bad
  location:
    row: 8
-    column: 0
+    column: 4
  end_location:
-    row: 12
-    column: 0
+    row: 8
+    column: 8
  fix: ~
 - kind:
    InvalidFunctionName: BAD
  location:
    row: 12
-    column: 0
+    column: 4
  end_location:
-    row: 16
-    column: 0
+    row: 12
+    column: 7
  fix: ~
 - kind:
    InvalidFunctionName: BAD_FUNC
  location:
    row: 16
-    column: 0
+    column: 4
  end_location:
-    row: 20
-    column: 0
+    row: 16
+    column: 12
  fix: ~
 - kind:
    InvalidFunctionName: testTest
  location:
    row: 40
-    column: 4
+    column: 8
  end_location:
-    row: 42
-    column: 0
+    row: 40
+    column: 16
  fix: ~

--- a/src/pep8_naming/snapshots/ruff__pep8_namingtestsN807_N807.py.snap
+++ b/src/pep8_naming/snapshots/ruff__pep8_namingtestsN807_N807.py.snap
@@ -5,17 +5,17 @@ expression: checks
 - kind: DunderFunctionName
  location:
    row: 1
-    column: 0
+    column: 4
  end_location:
-    row: 5
-    column: 0
+    row: 1
+    column: 11
  fix: ~
 - kind: DunderFunctionName
  location:
    row: 14
-    column: 4
+    column: 8
  end_location:
-    row: 17
-    column: 4
+    row: 14
+    column: 15
  fix: ~

--- a/src/pep8_naming/snapshots/ruff__pep8_namingtestsN818_N818.py.snap
+++ b/src/pep8_naming/snapshots/ruff__pep8_namingtestsN818_N818.py.snap
@@ -8,8 +8,8 @@ expression: checks
    row: 9
    column: 0
  end_location:
-    row: 13
-    column: 0
+    row: 10
+    column: 8
  fix: ~
 - kind:
    ErrorSuffixOnExceptionName: E
@@ -17,7 +17,7 @@ expression: checks
    row: 17
    column: 0
  end_location:
-    row: 19
-    column: 0
+    row: 18
+    column: 8
  fix: ~

--- a/src/pycodestyle/checks.rs
+++ b/src/pycodestyle/checks.rs
@@ -1,5 +1,5 @@
 use itertools::izip;
-use rustpython_ast::{Location, Stmt, StmtKind};
+use rustpython_ast::{Located, Location, Stmt, StmtKind};
 use rustpython_parser::ast::{Cmpop, Expr, ExprKind};

 use crate::ast::types::Range;
@@ -65,11 +65,11 @@ fn is_ambiguous_name(name: &str) -> bool {
 }

 /// E741
-pub fn ambiguous_variable_name(name: &str, location: Range) -> Option<Check> {
+pub fn ambiguous_variable_name<T>(name: &str, located: &Located<T>) -> Option<Check> {
    if is_ambiguous_name(name) {
        Some(Check::new(
            CheckKind::AmbiguousVariableName(name.to_string()),
-            location,
+            Range::from_located(located),
        ))
    } else {
        None
--- a/src/pycodestyle/mod.rs
+++ b/src/pycodestyle/mod.rs
@@ -44,4 +44,16 @@ mod tests {
        insta::assert_yaml_snapshot!(snapshot, checks);
        Ok(())
    }
+
+    #[test]
+    fn constant_literals() -> Result<()> {
+        let mut checks = test_path(
+            Path::new("./resources/test/fixtures/pycodestyle/constant_literals.py"),
+            &settings::Settings::for_rules(vec![CheckCode::E711, CheckCode::E712, CheckCode::F632]),
+            true,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
 }
--- a/src/pycodestyle/plugins.rs
+++ b/src/pycodestyle/plugins.rs
@@ -5,6 +5,7 @@ use rustc_hash::FxHashMap;
 use rustpython_ast::{Arguments, Location, StmtKind};
 use rustpython_parser::ast::{Cmpop, Constant, Expr, ExprKind, Stmt, Unaryop};

+use crate::ast::helpers;
 use crate::ast::helpers::{match_leading_content, match_trailing_content};
 use crate::ast::types::Range;
 use crate::ast::whitespace::leading_space;
@@ -46,9 +47,10 @@ pub fn literal_comparisons(
    let mut checks: Vec<Check> = vec![];

    let op = ops.first().unwrap();
-    let comparator = left;

    // Check `left`.
+    let mut comparator = left;
+    let next = &comparators[0];
    if check_none_comparisons
        && matches!(
            comparator.node,
@@ -59,24 +61,21 @@ pub fn literal_comparisons(
        )
    {
        if matches!(op, Cmpop::Eq) {
-            let mut check = Check::new(
+            let check = Check::new(
                CheckKind::NoneComparison(RejectedCmpop::Eq),
                Range::from_located(comparator),
            );
-            if checker.patch(check.kind.code()) {
-                // Dummy replacement
-                check.amend(Fix::dummy(expr.location));
+            if checker.patch(check.kind.code()) && !helpers::is_constant_non_singleton(next) {
                bad_ops.insert(0, Cmpop::Is);
            }
            checks.push(check);
        }
        if matches!(op, Cmpop::NotEq) {
-            let mut check = Check::new(
+            let check = Check::new(
                CheckKind::NoneComparison(RejectedCmpop::NotEq),
                Range::from_located(comparator),
            );
-            if checker.patch(check.kind.code()) {
-                check.amend(Fix::dummy(expr.location));
+            if checker.patch(check.kind.code()) && !helpers::is_constant_non_singleton(next) {
                bad_ops.insert(0, Cmpop::IsNot);
            }
            checks.push(check);
@@ -90,23 +89,21 @@ pub fn literal_comparisons(
        } = comparator.node
        {
            if matches!(op, Cmpop::Eq) {
-                let mut check = Check::new(
+                let check = Check::new(
                    CheckKind::TrueFalseComparison(value, RejectedCmpop::Eq),
                    Range::from_located(comparator),
                );
-                if checker.patch(check.kind.code()) {
-                    check.amend(Fix::dummy(expr.location));
+                if checker.patch(check.kind.code()) && !helpers::is_constant_non_singleton(next) {
                    bad_ops.insert(0, Cmpop::Is);
                }
                checks.push(check);
            }
            if matches!(op, Cmpop::NotEq) {
-                let mut check = Check::new(
+                let check = Check::new(
                    CheckKind::TrueFalseComparison(value, RejectedCmpop::NotEq),
                    Range::from_located(comparator),
                );
-                if checker.patch(check.kind.code()) {
-                    check.amend(Fix::dummy(expr.location));
+                if checker.patch(check.kind.code()) && !helpers::is_constant_non_singleton(next) {
                    bad_ops.insert(0, Cmpop::IsNot);
                }
                checks.push(check);
@@ -115,10 +112,10 @@ pub fn literal_comparisons(
    }

    // Check each comparator in order.
-    for (idx, (op, comparator)) in izip!(ops, comparators).enumerate() {
+    for (idx, (op, next)) in izip!(ops, comparators).enumerate() {
        if check_none_comparisons
            && matches!(
-                comparator.node,
+                next.node,
                ExprKind::Constant {
                    value: Constant::None,
                    kind: None
@@ -126,23 +123,25 @@ pub fn literal_comparisons(
            )
        {
            if matches!(op, Cmpop::Eq) {
-                let mut check = Check::new(
+                let check = Check::new(
                    CheckKind::NoneComparison(RejectedCmpop::Eq),
-                    Range::from_located(comparator),
+                    Range::from_located(next),
                );
-                if checker.patch(check.kind.code()) {
-                    check.amend(Fix::dummy(expr.location));
+                if checker.patch(check.kind.code())
+                    && !helpers::is_constant_non_singleton(comparator)
+                {
                    bad_ops.insert(idx, Cmpop::Is);
                }
                checks.push(check);
            }
            if matches!(op, Cmpop::NotEq) {
-                let mut check = Check::new(
+                let check = Check::new(
                    CheckKind::NoneComparison(RejectedCmpop::NotEq),
-                    Range::from_located(comparator),
+                    Range::from_located(next),
                );
-                if checker.patch(check.kind.code()) {
-                    check.amend(Fix::dummy(expr.location));
+                if checker.patch(check.kind.code())
+                    && !helpers::is_constant_non_singleton(comparator)
+                {
                    bad_ops.insert(idx, Cmpop::IsNot);
                }
                checks.push(check);
@@ -153,34 +152,40 @@ pub fn literal_comparisons(
            if let ExprKind::Constant {
                value: Constant::Bool(value),
                kind: None,
-            } = comparator.node
+            } = next.node
            {
                if matches!(op, Cmpop::Eq) {
-                    let mut check = Check::new(
+                    let check = Check::new(
                        CheckKind::TrueFalseComparison(value, RejectedCmpop::Eq),
-                        Range::from_located(comparator),
+                        Range::from_located(next),
                    );
-                    if checker.patch(check.kind.code()) {
-                        check.amend(Fix::dummy(expr.location));
+                    if checker.patch(check.kind.code())
+                        && !helpers::is_constant_non_singleton(comparator)
+                    {
                        bad_ops.insert(idx, Cmpop::Is);
                    }
                    checks.push(check);
                }
                if matches!(op, Cmpop::NotEq) {
-                    let mut check = Check::new(
+                    let check = Check::new(
                        CheckKind::TrueFalseComparison(value, RejectedCmpop::NotEq),
-                        Range::from_located(comparator),
+                        Range::from_located(next),
                    );
-                    if checker.patch(check.kind.code()) {
-                        check.amend(Fix::dummy(expr.location));
+                    if checker.patch(check.kind.code())
+                        && !helpers::is_constant_non_singleton(comparator)
+                    {
                        bad_ops.insert(idx, Cmpop::IsNot);
                    }
                    checks.push(check);
                }
            }
        }
+
+        comparator = next;
    }

+    // TODO(charlie): Respect `noqa` directives. If one of the operators has a
+    // `noqa`, but another doesn't, both will be removed here.
    if !bad_ops.is_empty() {
        // Replace the entire comparison expression.
        let ops = ops
@@ -190,9 +195,9 @@ pub fn literal_comparisons(
            .cloned()
            .collect::<Vec<_>>();
        if let Some(content) = compare(left, &ops, comparators) {
-            if let Some(check) = checks.last_mut() {
-                check.fix = Some(Fix::replacement(
-                    content,
+            for check in &mut checks {
+                check.amend(Fix::replacement(
+                    content.to_string(),
                    expr.location,
                    expr.end_location.unwrap(),
                ));
--- a/src/pycodestyle/snapshots/ruffpycodestyletests__E711_E711.py.snap
+++ b/src/pycodestyle/snapshots/ruffpycodestyletests__E711_E711.py.snap
@@ -139,13 +139,13 @@ expression: checks
    row: 26
    column: 12
  fix:
-    content: ""
+    content: x is None is not None
    location:
      row: 26
      column: 3
    end_location:
      row: 26
-      column: 3
+      column: 20
 - kind:
    NoneComparison: NotEq
  location:
--- a/src/pycodestyle/snapshots/ruffpycodestyletests__E712_E712.py.snap
+++ b/src/pycodestyle/snapshots/ruffpycodestyletests__E712_E712.py.snap
@@ -175,13 +175,13 @@ expression: checks
    row: 25
    column: 14
  fix:
-    content: ""
+    content: res is True is not False
    location:
      row: 25
      column: 3
    end_location:
      row: 25
-      column: 3
+      column: 23
 - kind:
    TrueFalseComparison:
      - false
--- a/src/pycodestyle/snapshots/ruffpycodestyletests__E722_E722.py.snap
+++ b/src/pycodestyle/snapshots/ruffpycodestyletests__E722_E722.py.snap
@@ -7,23 +7,23 @@ expression: checks
    row: 4
    column: 0
  end_location:
-    row: 7
-    column: 0
+    row: 5
+    column: 8
  fix: ~
 - kind: DoNotUseBareExcept
  location:
    row: 11
    column: 0
  end_location:
-    row: 14
-    column: 0
+    row: 12
+    column: 8
  fix: ~
 - kind: DoNotUseBareExcept
  location:
    row: 16
    column: 0
  end_location:
-    row: 19
-    column: 0
+    row: 17
+    column: 8
  fix: ~

--- a/src/pycodestyle/snapshots/ruffpycodestyletests__E741_E741.py.snap
+++ b/src/pycodestyle/snapshots/ruffpycodestyletests__E741_E741.py.snap
@@ -215,8 +215,8 @@ expression: checks
    row: 71
    column: 0
  end_location:
-    row: 74
-    column: 0
+    row: 72
+    column: 8
  fix: ~
 - kind:
    AmbiguousVariableName: l
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Charlie Marsh	a9f56ee76e	Bump version to 0.0.183	2022-12-15 23:15:12 -05:00
Charlie Marsh	b4bfa87104	Avoid removing partially-unused imports (#1259 )	2022-12-15 23:13:58 -05:00
Charlie Marsh	b9f42bf5e5	Remove extraneous test file	2022-12-15 23:12:19 -05:00
Edgar R. M	8281d414ca	Implement `flake8-errmsg` (#1258 )	2022-12-15 23:10:59 -05:00
Charlie Marsh	7e45a9f2e2	Avoid generating invalid statements when deleting from multi-statement lines (#1253 )	2022-12-15 22:17:31 -05:00
Reiner Gerecke	a000cd4a09	Test to prevent continious reformatting when used together with black (#1206 )	2022-12-15 15:26:41 -05:00
Martin Lehoux	d8b4b92733	Implement U016: Remove six compatibility code (#1013 )	2022-12-15 14:16:58 -05:00
Edgar R. M	27de342e75	Implement `pandas-vet` (#1235 )	2022-12-15 14:01:01 -05:00
Charlie Marsh	d805067683	Avoid fixing E711 and E712 issues that would cause F632 (#1248 )	2022-12-15 12:08:31 -05:00
Charlie Marsh	1ea2e93f8e	Bump version to 0.0.182	2022-12-14 22:57:22 -05:00
Charlie Marsh	dc180dc277	Negate ignore_names condition	2022-12-14 22:50:26 -05:00
Charlie Marsh	6be910ae07	Use more precise ranges for function and class checks (#1247 )	2022-12-14 22:40:00 -05:00
Charlie Marsh	ba85eb846c	Run cargo fmt	2022-12-14 21:52:44 -05:00
Charlie Marsh	d067efe265	Treat `extend-*` configuration options as "always extended" (#1245 )	2022-12-14 20:22:40 -05:00
Charlie Marsh	549ea2f85f	Ignore any `pyproject.toml` without a `[tool.ruff]` section (#1243 )	2022-12-14 19:35:52 -05:00
Charlie Marsh	d814ebd21f	Bump version to 0.0.181	2022-12-14 17:35:36 -05:00
Charlie Marsh	3f272b6cf8	Enable opt-out of `.gitignore` checks via `respect-gitignore` flag (#1242 )	2022-12-14 16:54:23 -05:00
Charlie Marsh	76891a8c07	Always check zero-depth CLI paths (#1241 )	2022-12-14 16:32:02 -05:00
Charlie Marsh	e389201b5f	Add new .gitignore behavior to BREAKING_CHANGES.md (#1240 )	2022-12-14 16:04:06 -05:00
Charlie Marsh	4b2020d03a	Automatically ignore files specified in `.gitignore` (#1234 )	2022-12-14 15:58:40 -05:00
Charlie Marsh	0aa356c96c	Avoid converting expression to statement in invald contexts (#1239 )	2022-12-14 13:57:25 -05:00
Charlie Marsh	630b4b627d	Apply fix to all errors in E711 and E712 autofix (#1238 )	2022-12-14 13:29:56 -05:00
Charlie Marsh	854cd14842	Bump version to 0.0.180	2022-12-14 13:21:10 -05:00
Chris Brendel	6b93c8403f	Apply CLI options even when no pyproject.toml is found (#1232 )	2022-12-13 22:55:04 -05:00
Charlie Marsh	765d21c7b0	Bump version to 0.0.179	2022-12-13 10:17:16 -05:00
Charlie Marsh	a58b9b5063	Upgrade RustPython to support parenthesized context managers (#1228 )	2022-12-13 10:16:43 -05:00
Charlie Marsh	f3e11a30cb	Bump version to 0.0.178	2022-12-12 22:06:04 -05:00
Charlie Marsh	2f3b5367ff	Add a note on extends to README	2022-12-12 21:36:39 -05:00
Charlie Marsh	92bc417e4e	Add support for glob patterns in `src` (#1225 )	2022-12-12 21:35:03 -05:00
Charlie Marsh	9853b0728b	Enable configuration files to "extend" other configuration files (#1219 )	2022-12-12 20:28:22 -05:00
Charlie Marsh	77709dcc41	Remove underscore from extend_exclude	2022-12-12 16:34:16 -05:00
Charlie Marsh	b0cb5fc7ef	Document current behavior around `pyproject.toml` discovery (#1213 )	2022-12-12 11:49:21 -05:00
Charlie Marsh	d6f51e55dd	Remove extraneous test_project	2022-12-12 10:53:12 -05:00
Charlie Marsh	4bb6b4851a	Rename p to path	2022-12-12 10:51:24 -05:00
Charlie Marsh	54c5ded938	Move settings path discovery into its own function	2022-12-12 10:50:08 -05:00
Charlie Marsh	0157fedab5	Move Python file resolution into resolver.rs (#1211 )	2022-12-12 10:43:50 -05:00
Charlie Marsh	cd69610741	Use `--config` everywhere if provided (#1210 )	2022-12-12 10:28:00 -05:00
Charlie Marsh	a3d06d0005	Move more commands into commands.rs (#1209 )	2022-12-12 10:22:47 -05:00
Charlie Marsh	ac6fa1dc88	Simplify some logic around configuration detection (#1197 )	2022-12-12 10:15:05 -05:00
Charlie Marsh	73794fc299	Resolve hierarchical settings and Python files in a single filesystem pass (#1205 )	2022-12-12 10:13:52 -05:00
Charlie Marsh	0adc9ed259	Support hierarchical settings for nested directories (#1190 )	2022-12-12 10:12:23 -05:00