Bump version to 0.0.70

Cargo.lock

@@ -64,6 +64,20 @@ dependencies = [
  "term",
 ]
 
+[[package]]
+name = "assert_cmd"
+version = "2.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "93ae1ddd39efd67689deb1979d80bad3bf7f2b09c6e6117c8d1f2443b5e2f83e"
+dependencies = [
+ "bstr",
+ "doc-comment",
+ "predicates",
+ "predicates-core",
+ "predicates-tree",
+ "wait-timeout",
+]
+
 [[package]]
 name = "async-channel"
 version = "1.7.1"
@@ -580,6 +594,12 @@ version = "0.1.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "56254986775e3233ffa9c4d7d3faaf6d36a2c09d30b20687e9f88bc8bafc16c8"
 
+[[package]]
+name = "difflib"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6184e33543162437515c2e2b48714794e37845ec9851711914eec9d308f6ebe8"
+
 [[package]]
 name = "digest"
 version = "0.8.1"
@@ -658,6 +678,12 @@ dependencies = [
  "winapi 0.3.9",
 ]
 
+[[package]]
+name = "doc-comment"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fea41bba32d969b513997752735605054bc0dfa92b4c56bf1189f2e174be7a10"
+
 [[package]]
 name = "either"
 version = "1.8.0"
@@ -1685,6 +1711,33 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "925383efa346730478fb4838dbe9137d2a47675ad789c546d150a6e1dd4ab31c"
 
+[[package]]
+name = "predicates"
+version = "2.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a5aab5be6e4732b473071984b3164dbbfb7a3674d30ea5ff44410b6bcd960c3c"
+dependencies = [
+ "difflib",
+ "itertools",
+ "predicates-core",
+]
+
+[[package]]
+name = "predicates-core"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da1c2388b1513e1b605fcec39a95e0a9e8ef088f71443ef37099fa9ae6673fcb"
+
+[[package]]
+name = "predicates-tree"
+version = "1.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4d86de6de25020a36c6d3643a86d9a6a9f552107c0559c60ea03551b5e16c032"
+dependencies = [
+ "predicates-core",
+ "termtree",
+]
+
 [[package]]
 name = "proc-macro-error"
 version = "1.0.4"
@@ -1907,9 +1960,10 @@ dependencies = [
 
 [[package]]
 name = "ruff"
-version = "0.0.68"
+version = "0.0.70"
 dependencies = [
  "anyhow",
+ "assert_cmd",
  "bincode",
  "cacache",
  "chrono",
@@ -2345,6 +2399,12 @@ dependencies = [
  "phf_codegen 0.8.0",
 ]
 
+[[package]]
+name = "termtree"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "507e9898683b6c43a9aa55b64259b721b52ba226e0f3779137e50ad114a4c90b"
+
 [[package]]
 name = "thiserror"
 version = "1.0.37"
@@ -2593,6 +2653,15 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f8e76fae08f03f96e166d2dfda232190638c10e0383841252416f9cfe2ae60e6"
 
+[[package]]
+name = "wait-timeout"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9f200f5b12eb75f8c1ed65abd4b2db8a6e1b138a20de009dacee265a2498f3f6"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "waker-fn"
 version = "1.1.0"

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff"
-version = "0.0.68"
+version = "0.0.70"
 edition = "2021"
 
 [lib]
@@ -40,6 +40,7 @@ strum_macros = "0.24.3"
 num-bigint = "0.4.3"
 
 [dev-dependencies]
+assert_cmd = "2.0.4"
 insta = { version = "1.19.1", features = ["yaml"] }
 
 [features]

README.md

@@ -57,7 +57,7 @@ ruff also works with [pre-commit](https://pre-commit.com):
 ```yaml
 repos:
   - repo: https://github.com/charliermarsh/ruff-pre-commit
-    rev: v0.0.48
+    rev: v0.0.70
     hooks:
       - id: lint
 ```
@@ -215,10 +215,10 @@ ruff also implements some of the most popular Flake8 plugins natively, including
 - [`flake8-builtins`](https://pypi.org/project/flake8-builtins/)
 - [`flake8-super`](https://pypi.org/project/flake8-super/)
 - [`flake8-print`](https://pypi.org/project/flake8-print/)
-- [`flake8-comprehensions`](https://pypi.org/project/flake8-comprehensions/) (11/16)
+- [`flake8-comprehensions`](https://pypi.org/project/flake8-comprehensions/) (12/16)
 - [`flake8-bugbear`](https://pypi.org/project/flake8-bugbear/) (3/32)
-- [`flake8-docstrings`](https://pypi.org/project/flake8-docstrings/) (6/47)
-- [`pyupgrade`](https://pypi.org/project/pyupgrade/) (partial)
+- [`flake8-docstrings`](https://pypi.org/project/flake8-docstrings/) (25/48)
+- [`pyupgrade`](https://pypi.org/project/pyupgrade/) (8/34)
 
 Beyond rule-set parity, ruff suffers from the following limitations vis-à-vis Flake8:
 
@@ -281,7 +281,7 @@ The 🛠 emoji indicates that a rule is automatically fixable by the `--fix` com
 | A002 | BuiltinArgumentShadowing | Argument `...` is shadowing a python builtin |  |  |
 | A003 | BuiltinAttributeShadowing | Class attribute `...` is shadowing a python builtin |  |  |
 | B011 | DoNotAssertFalse | Do not `assert False` (`python -O` removes these calls), raise `AssertionError()` |  | 🛠 |
-| B014 | DuplicateHandlerException | Exception handler with duplicate exception: `ValueError |  | 🛠 |
+| B014 | DuplicateHandlerException | Exception handler with duplicate exception: `ValueError` |  | 🛠 |
 | B025 | DuplicateTryBlockException | try-except block with duplicate exception `Exception` |  |  |
 | C400 | UnnecessaryGeneratorList | Unnecessary generator - rewrite as a list comprehension |  |  |
 | C401 | UnnecessaryGeneratorSet | Unnecessary generator - rewrite as a set comprehension |  |  |
@@ -293,6 +293,7 @@ The 🛠 emoji indicates that a rule is automatically fixable by the `--fix` com
 | C408 | UnnecessaryCollectionCall | Unnecessary <dict/list/tuple> call - rewrite as a literal |  |  |
 | C409 | UnnecessaryLiteralWithinTupleCall | Unnecessary <list/tuple> literal passed to tuple() - remove the outer call to tuple() |  |  |
 | C410 | UnnecessaryLiteralWithinListCall | Unnecessary <list/tuple> literal passed to list() - rewrite as a list literal |  |  |
+| C414 | UnnecessaryDoubleCastOrProcess | Unnecessary <list/reversed/set/sorted/tuple> call within <list/set/sorted/tuple>(). |  |  |
 | C415 | UnnecessarySubscriptReversal | Unnecessary subscript reversal of iterable within <reversed/set/sorted>() |  |  |
 | T201 | PrintFound | `print` found |  | 🛠 |
 | T203 | PPrintFound | `pprint` found |  | 🛠 |
@@ -304,12 +305,31 @@ The 🛠 emoji indicates that a rule is automatically fixable by the `--fix` com
 | U006 | UsePEP585Annotation | Use `list` instead of `List` for type annotations |  | 🛠 |
 | U007 | UsePEP604Annotation | Use `X \| Y` for type annotations |  | 🛠 |
 | U008 | SuperCallWithParameters | Use `super()` instead of `super(__class__, self)` |  | 🛠 |
-| D200 | OneLinerDocstring | One-line docstring should fit on one line |  |  |
-| D205 | BlankLineAfterSummary | 1 blank line required between summary line and description |  |  |
+| D100 | PublicModule | Missing docstring in public module |  |  |
+| D101 | PublicClass | Missing docstring in public class |  |  |
+| D102 | PublicMethod | Missing docstring in public method |  |  |
+| D103 | PublicFunction | Missing docstring in public function |  |  |
+| D104 | PublicPackage | Missing docstring in public package |  |  |
+| D105 | MagicMethod | Missing docstring in magic method |  |  |
+| D106 | PublicNestedClass | Missing docstring in public nested class |  |  |
+| D107 | PublicInit | Missing docstring in __init__ |  |  |
+| D200 | FitsOnOneLine | One-line docstring should fit on one line |  |  |
+| D205 | NoBlankLineAfterSummary | 1 blank line required between summary line and description |  |  |
 | D209 | NewLineAfterLastParagraph | Multi-line docstring closing quotes should be on a separate line |  |  |
 | D210 | NoSurroundingWhitespace | No whitespaces allowed surrounding docstring text |  |  |
-| D400 | DocstringEndsInNonPeriod | First line should end with a period |  |  |
-| D419 | EmptyDocstring | Docstring is empty |  |  |
+| D212 | MultiLineSummaryFirstLine | Multi-line docstring summary should start at the first line |  |  |
+| D213 | MultiLineSummarySecondLine | Multi-line docstring summary should start at the second line |  |  |
+| D300 | UsesTripleQuotes | Use """triple double quotes""" |  |  |
+| D400 | EndsInPeriod | First line should end with a period |  |  |
+| D402 | NoSignature | First line should not be the function's 'signature' |  |  |
+| D403 | FirstLineCapitalized | First word of the first line should be properly capitalized |  |  |
+| D415 | EndsInPunctuation | First line should end with a period, question mark, or exclamation point |  |  |
+| D419 | NonEmpty | Docstring is empty |  |  |
+| D201 | NoBlankLineBeforeFunction | No blank lines allowed before function docstring (found 1) |  |  |
+| D202 | NoBlankLineAfterFunction | No blank lines allowed after function docstring (found 1) |  |  |
+| D211 | NoBlankLineBeforeClass | No blank lines allowed before class docstring |  |  |
+| D203 | OneBlankLineBeforeClass | 1 blank line required before class docstring |  |  |
+| D204 | OneBlankLineAfterClass | 1 blank line required after class docstring |  |  |
 | M001 | UnusedNOQA | Unused `noqa` directive |  | 🛠 |
 
 ## Integrations

resources/test/fixtures/C414.py

@@ -0,0 +1,14 @@
+x = [1, 2, 3]
+list(list(x))
+list(tuple(x))
+tuple(list(x))
+tuple(tuple(x))
+set(set(x))
+set(list(x))
+set(tuple(x))
+set(sorted(x))
+set(reversed(x))
+sorted(list(x))
+sorted(tuple(x))
+sorted(sorted(x))
+sorted(reversed(x))

setup.py

@@ -0,0 +1,23 @@
+import sys
+
+from setuptools import setup
+
+sys.stderr.write(
+    """
+===============================
+Unsupported installation method
+===============================
+ruff no longer supports installation with `python setup.py install`.
+Please use `python -m pip install .` instead.
+"""
+)
+sys.exit(1)
+
+
+# The below code will never execute, however GitHub is particularly
+# picky about where it finds Python packaging metadata.
+# See: https://github.com/github/feedback/discussions/6456
+#
+# To be removed once GitHub catches up.
+
+setup(name="ruff", install_requires=[])

src/ast/checkers.rs

@@ -1004,6 +1004,68 @@ pub fn unnecessary_literal_within_list_call(
     None
 }
 
+pub fn unnecessary_double_cast_or_process(
+    expr: &Expr,
+    func: &Expr,
+    args: &[Expr],
+) -> Option<Check> {
+    if let ExprKind::Name { id: outer, .. } = &func.node {
+        if outer == "list"
+            || outer == "tuple"
+            || outer == "set"
+            || outer == "reversed"
+            || outer == "sorted"
+        {
+            if let Some(arg) = args.first() {
+                if let ExprKind::Call { func, .. } = &arg.node {
+                    if let ExprKind::Name { id: inner, .. } = &func.node {
+                        // Ex) set(tuple(...))
+                        if (outer == "set" || outer == "sorted")
+                            && (inner == "list"
+                                || inner == "tuple"
+                                || inner == "reversed"
+                                || inner == "sorted")
+                        {
+                            return Some(Check::new(
+                                CheckKind::UnnecessaryDoubleCastOrProcess(
+                                    inner.to_string(),
+                                    outer.to_string(),
+                                ),
+                                Range::from_located(expr),
+                            ));
+                        }
+
+                        // Ex) list(tuple(...))
+                        if (outer == "list" || outer == "tuple")
+                            && (inner == "list" || inner == "tuple")
+                        {
+                            return Some(Check::new(
+                                CheckKind::UnnecessaryDoubleCastOrProcess(
+                                    inner.to_string(),
+                                    outer.to_string(),
+                                ),
+                                Range::from_located(expr),
+                            ));
+                        }
+
+                        // Ex) set(set(...))
+                        if outer == "set" && inner == "set" {
+                            return Some(Check::new(
+                                CheckKind::UnnecessaryDoubleCastOrProcess(
+                                    inner.to_string(),
+                                    outer.to_string(),
+                                ),
+                                Range::from_located(expr),
+                            ));
+                        }
+                    }
+                }
+            }
+        }
+    }
+    None
+}
+
 pub fn unnecessary_subscript_reversal(expr: &Expr, func: &Expr, args: &[Expr]) -> Option<Check> {
     if let Some(first_arg) = args.first() {
         if let ExprKind::Name { id, .. } = &func.node {

src/ast/operations.rs

@@ -134,7 +134,7 @@ impl<'a> SourceCodeLocator<'a> {
         }
     }
 
-    pub fn slice_source_code_at(&mut self, location: &Location) -> &'a str {
+    fn init(&mut self) {
         if !self.initialized {
             let mut offset = 0;
             for i in self.content.lines() {
@@ -142,24 +142,40 @@ impl<'a> SourceCodeLocator<'a> {
                 offset += i.len();
                 offset += 1;
             }
+            self.offsets.push(offset);
             self.initialized = true;
         }
+    }
+
+    pub fn slice_source_code_at(&mut self, location: &Location) -> &'a str {
+        self.init();
         let offset = self.offsets[location.row() - 1] + location.column() - 1;
         &self.content[offset..]
     }
 
     pub fn slice_source_code_range(&mut self, range: &Range) -> &'a str {
-        if !self.initialized {
-            let mut offset = 0;
-            for i in self.content.lines() {
-                self.offsets.push(offset);
-                offset += i.len();
-                offset += 1;
-            }
-            self.initialized = true;
-        }
+        self.init();
         let start = self.offsets[range.location.row() - 1] + range.location.column() - 1;
         let end = self.offsets[range.end_location.row() - 1] + range.end_location.column() - 1;
         &self.content[start..end]
     }
+
+    pub fn partition_source_code_at(
+        &mut self,
+        outer: &Range,
+        inner: &Range,
+    ) -> (&'a str, &'a str, &'a str) {
+        self.init();
+        let outer_start = self.offsets[outer.location.row() - 1] + outer.location.column() - 1;
+        let outer_end =
+            self.offsets[outer.end_location.row() - 1] + outer.end_location.column() - 1;
+        let inner_start = self.offsets[inner.location.row() - 1] + inner.location.column() - 1;
+        let inner_end =
+            self.offsets[inner.end_location.row() - 1] + inner.end_location.column() - 1;
+        (
+            &self.content[outer_start..inner_start],
+            &self.content[inner_start..inner_end],
+            &self.content[inner_end..outer_end],
+        )
+    }
 }

src/check_ast.rs

@@ -21,17 +21,18 @@ use crate::ast::visitor::{walk_excepthandler, Visitor};
 use crate::ast::{checkers, helpers, operations, visitor};
 use crate::autofix::{fixer, fixes};
 use crate::checks::{Check, CheckCode, CheckKind};
-use crate::docstrings::{Docstring, DocstringKind};
+use crate::docstrings::{Definition, DefinitionKind, Documentable};
 use crate::python::builtins::{BUILTINS, MAGIC_GLOBALS};
 use crate::python::future::ALL_FEATURE_NAMES;
 use crate::settings::{PythonVersion, Settings};
+use crate::visibility::{module_visibility, transition_scope, Modifier, Visibility, VisibleScope};
 use crate::{docstrings, plugins};
 
 pub const GLOBAL_SCOPE_INDEX: usize = 0;
 
 pub struct Checker<'a> {
     // Input data.
-    path: &'a Path,
+    pub(crate) path: &'a Path,
     // TODO(charlie): Separate immutable from mutable state. (None of these should ever change.)
     pub(crate) locator: SourceCodeLocator<'a>,
     pub(crate) settings: &'a Settings,
@@ -39,7 +40,7 @@ pub struct Checker<'a> {
     // Computed checks.
     checks: Vec<Check>,
     // Docstring tracking.
-    docstrings: Vec<Docstring<'a>>,
+    docstrings: Vec<(Definition<'a>, Visibility)>,
     // Edit tracking.
     // TODO(charlie): Instead of exposing deletions, wrap in a public API.
     pub(crate) deletions: BTreeSet<usize>,
@@ -52,11 +53,11 @@ pub struct Checker<'a> {
     dead_scopes: Vec<usize>,
     deferred_string_annotations: Vec<(Range, &'a str)>,
     deferred_annotations: Vec<(&'a Expr, Vec<usize>, Vec<usize>)>,
-    deferred_functions: Vec<(&'a Stmt, Vec<usize>, Vec<usize>)>,
+    deferred_functions: Vec<(&'a Stmt, Vec<usize>, Vec<usize>, VisibleScope)>,
     deferred_lambdas: Vec<(&'a Expr, Vec<usize>, Vec<usize>)>,
     deferred_assignments: Vec<usize>,
     // Internal, derivative state.
-    pub(crate) initial: bool,
+    visible_scope: VisibleScope,
     in_f_string: Option<Range>,
     in_annotation: bool,
     in_literal: bool,
@@ -91,7 +92,10 @@ impl<'a> Checker<'a> {
             deferred_functions: Default::default(),
             deferred_lambdas: Default::default(),
             deferred_assignments: Default::default(),
-            initial: true,
+            visible_scope: VisibleScope {
+                modifier: Modifier::Module,
+                visibility: module_visibility(path),
+            },
             in_f_string: None,
             in_annotation: Default::default(),
             in_literal: Default::default(),
@@ -125,36 +129,8 @@ where
             StmtKind::Import { .. } => {
                 self.futures_allowed = false;
             }
-            StmtKind::Expr { value } => {
-                // Track all docstrings: module-, class-, and function-level.
-                let mut is_module_docstring = false;
-                if matches!(
-                    &value.node,
-                    ExprKind::Constant {
-                        value: Constant::Str(_),
-                        ..
-                    }
-                ) {
-                    if let Some(docstring) = docstrings::extract(self, stmt, value) {
-                        if matches!(&docstring.kind, DocstringKind::Module) {
-                            is_module_docstring = true;
-                        }
-                        self.docstrings.push(docstring);
-                    }
-                }
-
-                if !is_module_docstring {
-                    if !self.seen_import_boundary
-                        && !operations::in_nested_block(&self.parent_stack, &self.parents)
-                    {
-                        self.seen_import_boundary = true;
-                    }
-                    self.futures_allowed = false;
-                }
-            }
             node => {
                 self.futures_allowed = false;
-
                 if !self.seen_import_boundary
                     && !helpers::is_assignment_to_a_dunder(node)
                     && !operations::in_nested_block(&self.parent_stack, &self.parents)
@@ -590,18 +566,31 @@ where
             StmtKind::Delete { .. } => {}
             _ => {}
         }
-        self.initial = false;
 
         // Recurse.
+        let prev_visibile_scope = self.visible_scope.clone();
         match &stmt.node {
-            StmtKind::FunctionDef { .. } | StmtKind::AsyncFunctionDef { .. } => {
+            StmtKind::FunctionDef { body, .. } | StmtKind::AsyncFunctionDef { body, .. } => {
+                let definition =
+                    docstrings::extract(&self.visible_scope, stmt, body, &Documentable::Function);
+                let scope = transition_scope(&self.visible_scope, stmt, &Documentable::Function);
+                self.docstrings.push((definition, scope.visibility.clone()));
+                self.visible_scope = scope;
+
                 self.deferred_functions.push((
                     stmt,
                     self.scope_stack.clone(),
                     self.parent_stack.clone(),
+                    self.visible_scope.clone(),
                 ));
             }
             StmtKind::ClassDef { body, .. } => {
+                let definition =
+                    docstrings::extract(&self.visible_scope, stmt, body, &Documentable::Class);
+                let scope = transition_scope(&self.visible_scope, stmt, &Documentable::Class);
+                self.docstrings.push((definition, scope.visibility.clone()));
+                self.visible_scope = scope;
+
                 for stmt in body {
                     self.visit_stmt(stmt);
                 }
@@ -629,6 +618,7 @@ where
             }
             _ => visitor::walk_stmt(self, stmt),
         };
+        self.visible_scope = prev_visibile_scope;
 
         // Post-visit.
         if let StmtKind::ClassDef { name, .. } = &stmt.node {
@@ -837,6 +827,15 @@ where
                         self.checks.push(check);
                     };
                 }
+
+                if self.settings.enabled.contains(&CheckCode::C414) {
+                    if let Some(check) =
+                        checkers::unnecessary_double_cast_or_process(expr, func, args)
+                    {
+                        self.checks.push(check);
+                    };
+                }
+
                 if self.settings.enabled.contains(&CheckCode::C415) {
                     if let Some(check) = checkers::unnecessary_subscript_reversal(expr, func, args)
                     {
@@ -1643,6 +1642,25 @@ impl<'a> Checker<'a> {
         }
     }
 
+    fn visit_docstring<'b>(&mut self, python_ast: &'b Suite) -> bool
+    where
+        'b: 'a,
+    {
+        let docstring = docstrings::docstring_from(python_ast);
+        self.docstrings.push((
+            Definition {
+                kind: if self.path.ends_with("__init__.py") {
+                    DefinitionKind::Package
+                } else {
+                    DefinitionKind::Module
+                },
+                docstring,
+            },
+            self.visible_scope.visibility.clone(),
+        ));
+        docstring.is_some()
+    }
+
     fn check_deferred_annotations(&mut self) {
         while let Some((expr, scopes, parents)) = self.deferred_annotations.pop() {
             self.parent_stack = parents;
@@ -1695,9 +1713,10 @@ impl<'a> Checker<'a> {
     }
 
     fn check_deferred_functions(&mut self) {
-        while let Some((stmt, scopes, parents)) = self.deferred_functions.pop() {
+        while let Some((stmt, scopes, parents, visibility)) = self.deferred_functions.pop() {
             self.parent_stack = parents;
             self.scope_stack = scopes;
+            self.visible_scope = visibility;
             self.push_scope(Scope::new(ScopeKind::Function(Default::default())));
 
             match &stmt.node {
@@ -1889,10 +1908,27 @@ impl<'a> Checker<'a> {
     }
 
     fn check_docstrings(&mut self) {
-        while let Some(docstring) = self.docstrings.pop() {
+        while let Some((docstring, visibility)) = self.docstrings.pop() {
+            if !docstrings::not_empty(self, &docstring) {
+                continue;
+            }
+            if !docstrings::not_missing(self, &docstring, &visibility) {
+                continue;
+            }
             if self.settings.enabled.contains(&CheckCode::D200) {
                 docstrings::one_liner(self, &docstring);
             }
+            if self.settings.enabled.contains(&CheckCode::D201)
+                || self.settings.enabled.contains(&CheckCode::D202)
+            {
+                docstrings::blank_before_after_function(self, &docstring);
+            }
+            if self.settings.enabled.contains(&CheckCode::D203)
+                || self.settings.enabled.contains(&CheckCode::D204)
+                || self.settings.enabled.contains(&CheckCode::D211)
+            {
+                docstrings::blank_before_after_class(self, &docstring);
+            }
             if self.settings.enabled.contains(&CheckCode::D205) {
                 docstrings::blank_after_summary(self, &docstring);
             }
@@ -1902,11 +1938,25 @@ impl<'a> Checker<'a> {
             if self.settings.enabled.contains(&CheckCode::D210) {
                 docstrings::no_surrounding_whitespace(self, &docstring);
             }
+            if self.settings.enabled.contains(&CheckCode::D212)
+                || self.settings.enabled.contains(&CheckCode::D213)
+            {
+                docstrings::multi_line_summary_start(self, &docstring);
+            }
+            if self.settings.enabled.contains(&CheckCode::D300) {
+                docstrings::triple_quotes(self, &docstring);
+            }
             if self.settings.enabled.contains(&CheckCode::D400) {
                 docstrings::ends_with_period(self, &docstring);
             }
-            if self.settings.enabled.contains(&CheckCode::D419) {
-                docstrings::not_empty(self, &docstring);
+            if self.settings.enabled.contains(&CheckCode::D402) {
+                docstrings::no_signature(self, &docstring);
+            }
+            if self.settings.enabled.contains(&CheckCode::D403) {
+                docstrings::capitalized(self, &docstring);
+            }
+            if self.settings.enabled.contains(&CheckCode::D415) {
+                docstrings::ends_with_punctuation(self, &docstring);
             }
         }
     }
@@ -1960,6 +2010,13 @@ pub fn check_ast(
     checker.push_scope(Scope::new(ScopeKind::Module));
     checker.bind_builtins();
 
+    // Check for module docstring.
+    let python_ast = if checker.visit_docstring(python_ast) {
+        &python_ast[1..]
+    } else {
+        python_ast
+    };
+
     // Iterate over the AST.
     for stmt in python_ast {
         checker.visit_stmt(stmt);

src/checks.rs

@@ -137,6 +137,7 @@ pub enum CheckCode {
     C408,
     C409,
     C410,
+    C414,
     C415,
     // flake8-print
     T201,
@@ -151,12 +152,31 @@ pub enum CheckCode {
     U007,
     U008,
     // pydocstyle
+    D100,
+    D101,
+    D102,
+    D103,
+    D104,
+    D105,
+    D106,
+    D107,
     D200,
     D205,
     D209,
     D210,
+    D212,
+    D213,
+    D300,
     D400,
+    D402,
+    D403,
+    D415,
     D419,
+    D201,
+    D202,
+    D211,
+    D203,
+    D204,
     // Meta
     M001,
 }
@@ -240,6 +260,7 @@ pub enum CheckKind {
     UnnecessaryCollectionCall(String),
     UnnecessaryLiteralWithinTupleCall(String),
     UnnecessaryLiteralWithinListCall(String),
+    UnnecessaryDoubleCastOrProcess(String, String),
     UnnecessarySubscriptReversal(String),
     // flake8-print
     PrintFound,
@@ -254,12 +275,31 @@ pub enum CheckKind {
     UsePEP604Annotation,
     SuperCallWithParameters,
     // pydocstyle
-    OneLinerDocstring,
-    BlankLineAfterSummary,
+    EndsInPeriod,
+    EndsInPunctuation,
+    FirstLineCapitalized,
+    FitsOnOneLine,
+    MultiLineSummaryFirstLine,
+    MultiLineSummarySecondLine,
     NewLineAfterLastParagraph,
+    NoBlankLineAfterSummary,
     NoSurroundingWhitespace,
-    EmptyDocstring,
-    DocstringEndsInNonPeriod,
+    NonEmpty,
+    UsesTripleQuotes,
+    NoSignature,
+    NoBlankLineBeforeFunction(usize),
+    NoBlankLineAfterFunction(usize),
+    NoBlankLineBeforeClass(usize),
+    OneBlankLineBeforeClass(usize),
+    OneBlankLineAfterClass(usize),
+    PublicModule,
+    PublicClass,
+    PublicMethod,
+    PublicFunction,
+    PublicPackage,
+    MagicMethod,
+    PublicNestedClass,
+    PublicInit,
     // Meta
     UnusedNOQA(Option<Vec<String>>),
 }
@@ -350,6 +390,10 @@ impl CheckCode {
             CheckCode::C410 => {
                 CheckKind::UnnecessaryLiteralWithinListCall("<list/tuple>".to_string())
             }
+            CheckCode::C414 => CheckKind::UnnecessaryDoubleCastOrProcess(
+                "<list/reversed/set/sorted/tuple>".to_string(),
+                "<list/set/sorted/tuple>".to_string(),
+            ),
             CheckCode::C415 => {
                 CheckKind::UnnecessarySubscriptReversal("<reversed/set/sorted>".to_string())
             }
@@ -369,12 +413,31 @@ impl CheckCode {
             CheckCode::U007 => CheckKind::UsePEP604Annotation,
             CheckCode::U008 => CheckKind::SuperCallWithParameters,
             // pydocstyle
-            CheckCode::D200 => CheckKind::OneLinerDocstring,
-            CheckCode::D205 => CheckKind::BlankLineAfterSummary,
+            CheckCode::D100 => CheckKind::PublicModule,
+            CheckCode::D101 => CheckKind::PublicClass,
+            CheckCode::D102 => CheckKind::PublicMethod,
+            CheckCode::D103 => CheckKind::PublicFunction,
+            CheckCode::D104 => CheckKind::PublicPackage,
+            CheckCode::D105 => CheckKind::MagicMethod,
+            CheckCode::D106 => CheckKind::PublicNestedClass,
+            CheckCode::D107 => CheckKind::PublicInit,
+            CheckCode::D200 => CheckKind::FitsOnOneLine,
+            CheckCode::D205 => CheckKind::NoBlankLineAfterSummary,
             CheckCode::D209 => CheckKind::NewLineAfterLastParagraph,
             CheckCode::D210 => CheckKind::NoSurroundingWhitespace,
-            CheckCode::D400 => CheckKind::DocstringEndsInNonPeriod,
-            CheckCode::D419 => CheckKind::EmptyDocstring,
+            CheckCode::D400 => CheckKind::EndsInPeriod,
+            CheckCode::D419 => CheckKind::NonEmpty,
+            CheckCode::D212 => CheckKind::MultiLineSummaryFirstLine,
+            CheckCode::D213 => CheckKind::MultiLineSummarySecondLine,
+            CheckCode::D300 => CheckKind::UsesTripleQuotes,
+            CheckCode::D402 => CheckKind::NoSignature,
+            CheckCode::D403 => CheckKind::FirstLineCapitalized,
+            CheckCode::D415 => CheckKind::EndsInPunctuation,
+            CheckCode::D201 => CheckKind::NoBlankLineBeforeFunction(1),
+            CheckCode::D202 => CheckKind::NoBlankLineAfterFunction(1),
+            CheckCode::D211 => CheckKind::NoBlankLineBeforeClass(1),
+            CheckCode::D203 => CheckKind::OneBlankLineBeforeClass(0),
+            CheckCode::D204 => CheckKind::OneBlankLineAfterClass(0),
             // Meta
             CheckCode::M001 => CheckKind::UnusedNOQA(None),
         }
@@ -449,6 +512,7 @@ impl CheckKind {
             CheckKind::UnnecessaryCollectionCall(_) => &CheckCode::C408,
             CheckKind::UnnecessaryLiteralWithinTupleCall(..) => &CheckCode::C409,
             CheckKind::UnnecessaryLiteralWithinListCall(..) => &CheckCode::C410,
+            CheckKind::UnnecessaryDoubleCastOrProcess(..) => &CheckCode::C414,
             CheckKind::UnnecessarySubscriptReversal(_) => &CheckCode::C415,
             // flake8-print
             CheckKind::PrintFound => &CheckCode::T201,
@@ -463,12 +527,31 @@ impl CheckKind {
             CheckKind::UselessObjectInheritance(_) => &CheckCode::U004,
             CheckKind::SuperCallWithParameters => &CheckCode::U008,
             // pydocstyle
-            CheckKind::OneLinerDocstring => &CheckCode::D200,
-            CheckKind::BlankLineAfterSummary => &CheckCode::D205,
+            CheckKind::PublicModule => &CheckCode::D100,
+            CheckKind::PublicClass => &CheckCode::D101,
+            CheckKind::PublicMethod => &CheckCode::D102,
+            CheckKind::PublicFunction => &CheckCode::D103,
+            CheckKind::PublicPackage => &CheckCode::D104,
+            CheckKind::MagicMethod => &CheckCode::D105,
+            CheckKind::PublicNestedClass => &CheckCode::D106,
+            CheckKind::PublicInit => &CheckCode::D107,
+            CheckKind::FitsOnOneLine => &CheckCode::D200,
+            CheckKind::NoBlankLineAfterSummary => &CheckCode::D205,
             CheckKind::NewLineAfterLastParagraph => &CheckCode::D209,
             CheckKind::NoSurroundingWhitespace => &CheckCode::D210,
-            CheckKind::DocstringEndsInNonPeriod => &CheckCode::D400,
-            CheckKind::EmptyDocstring => &CheckCode::D419,
+            CheckKind::EndsInPeriod => &CheckCode::D400,
+            CheckKind::NonEmpty => &CheckCode::D419,
+            CheckKind::MultiLineSummaryFirstLine => &CheckCode::D212,
+            CheckKind::MultiLineSummarySecondLine => &CheckCode::D213,
+            CheckKind::UsesTripleQuotes => &CheckCode::D300,
+            CheckKind::NoSignature => &CheckCode::D402,
+            CheckKind::FirstLineCapitalized => &CheckCode::D403,
+            CheckKind::EndsInPunctuation => &CheckCode::D415,
+            CheckKind::NoBlankLineBeforeFunction(_) => &CheckCode::D201,
+            CheckKind::NoBlankLineAfterFunction(_) => &CheckCode::D202,
+            CheckKind::NoBlankLineBeforeClass(_) => &CheckCode::D211,
+            CheckKind::OneBlankLineBeforeClass(_) => &CheckCode::D203,
+            CheckKind::OneBlankLineAfterClass(_) => &CheckCode::D204,
             // Meta
             CheckKind::UnusedNOQA(_) => &CheckCode::M001,
         }
@@ -625,7 +708,7 @@ impl CheckKind {
             CheckKind::DuplicateHandlerException(names) => {
                 if names.len() == 1 {
                     let name = &names[0];
-                    format!("Exception handler with duplicate exception: `{name}")
+                    format!("Exception handler with duplicate exception: `{name}`")
                 } else {
                     let names = names.iter().map(|name| format!("`{name}`")).join(", ");
                     format!("Exception handler with duplicate exceptions: {names}")
@@ -681,6 +764,9 @@ impl CheckKind {
                     )
                 }
             }
+            CheckKind::UnnecessaryDoubleCastOrProcess(inner, outer) => {
+                format!("Unnecessary {inner} call within {outer}().")
+            }
             CheckKind::UnnecessarySubscriptReversal(func) => {
                 format!("Unnecessary subscript reversal of iterable within {func}()")
             }
@@ -713,8 +799,8 @@ impl CheckKind {
                 "Use `super()` instead of `super(__class__, self)`".to_string()
             }
             // pydocstyle
-            CheckKind::OneLinerDocstring => "One-line docstring should fit on one line".to_string(),
-            CheckKind::BlankLineAfterSummary => {
+            CheckKind::FitsOnOneLine => "One-line docstring should fit on one line".to_string(),
+            CheckKind::NoBlankLineAfterSummary => {
                 "1 blank line required between summary line and description".to_string()
             }
             CheckKind::NewLineAfterLastParagraph => {
@@ -723,10 +809,48 @@ impl CheckKind {
             CheckKind::NoSurroundingWhitespace => {
                 "No whitespaces allowed surrounding docstring text".to_string()
             }
-            CheckKind::DocstringEndsInNonPeriod => {
-                "First line should end with a period".to_string()
+            CheckKind::EndsInPeriod => "First line should end with a period".to_string(),
+            CheckKind::NonEmpty => "Docstring is empty".to_string(),
+            CheckKind::EndsInPunctuation => {
+                "First line should end with a period, question mark, or exclamation point"
+                    .to_string()
             }
-            CheckKind::EmptyDocstring => "Docstring is empty".to_string(),
+            CheckKind::FirstLineCapitalized => {
+                "First word of the first line should be properly capitalized".to_string()
+            }
+            CheckKind::UsesTripleQuotes => r#"Use """triple double quotes""""#.to_string(),
+            CheckKind::MultiLineSummaryFirstLine => {
+                "Multi-line docstring summary should start at the first line".to_string()
+            }
+            CheckKind::MultiLineSummarySecondLine => {
+                "Multi-line docstring summary should start at the second line".to_string()
+            }
+            CheckKind::NoSignature => {
+                "First line should not be the function's 'signature'".to_string()
+            }
+            CheckKind::NoBlankLineBeforeFunction(num_lines) => {
+                format!("No blank lines allowed before function docstring (found {num_lines})")
+            }
+            CheckKind::NoBlankLineAfterFunction(num_lines) => {
+                format!("No blank lines allowed after function docstring (found {num_lines})")
+            }
+            CheckKind::NoBlankLineBeforeClass(_) => {
+                "No blank lines allowed before class docstring".to_string()
+            }
+            CheckKind::OneBlankLineBeforeClass(_) => {
+                "1 blank line required before class docstring".to_string()
+            }
+            CheckKind::OneBlankLineAfterClass(_) => {
+                "1 blank line required after class docstring".to_string()
+            }
+            CheckKind::PublicModule => "Missing docstring in public module".to_string(),
+            CheckKind::PublicClass => "Missing docstring in public class".to_string(),
+            CheckKind::PublicMethod => "Missing docstring in public method".to_string(),
+            CheckKind::PublicFunction => "Missing docstring in public function".to_string(),
+            CheckKind::PublicPackage => "Missing docstring in public package".to_string(),
+            CheckKind::MagicMethod => "Missing docstring in magic method".to_string(),
+            CheckKind::PublicNestedClass => "Missing docstring in public nested class".to_string(),
+            CheckKind::PublicInit => "Missing docstring in __init__".to_string(),
             // Meta
             CheckKind::UnusedNOQA(codes) => match codes {
                 None => "Unused `noqa` directive".to_string(),

src/cli.rs

@@ -78,6 +78,9 @@ pub struct Cli {
     // TODO(charlie): This should be a sub-command.
     #[arg(long, hide = true)]
     pub autoformat: bool,
+    /// The name of the file when passing it through stdin.
+    #[arg(long)]
+    pub stdin_filename: Option<String>,
 }
 
 pub enum Warnable {

src/docstrings.rs

@@ -1,198 +1,633 @@
+use once_cell::sync::Lazy;
+use regex::Regex;
+use rustpython_ast::{Constant, Expr, ExprKind, Location, Stmt, StmtKind};
+
 use crate::ast::types::Range;
 use crate::check_ast::Checker;
-use crate::checks::{Check, CheckKind};
-use rustpython_ast::{Constant, Expr, ExprKind, Stmt, StmtKind};
+use crate::checks::{Check, CheckCode, CheckKind};
+use crate::visibility::{is_init, is_magic, is_overload, Modifier, Visibility, VisibleScope};
 
 #[derive(Debug)]
-pub enum DocstringKind {
+pub enum DefinitionKind<'a> {
     Module,
-    Function,
-    Class,
+    Package,
+    Class(&'a Stmt),
+    NestedClass(&'a Stmt),
+    Function(&'a Stmt),
+    NestedFunction(&'a Stmt),
+    Method(&'a Stmt),
 }
 
 #[derive(Debug)]
-pub struct Docstring<'a> {
-    pub kind: DocstringKind,
-    pub parent: Option<&'a Stmt>,
-    pub expr: &'a Expr,
+pub struct Definition<'a> {
+    pub kind: DefinitionKind<'a>,
+    pub docstring: Option<&'a Expr>,
 }
 
-/// Extract a docstring from an expression.
-pub fn extract<'a, 'b>(
-    checker: &'a Checker,
-    stmt: &'b Stmt,
-    expr: &'b Expr,
-) -> Option<Docstring<'b>> {
-    let defined_in = checker
-        .binding_context()
-        .defined_in
-        .map(|index| checker.parents[index]);
+pub enum Documentable {
+    Class,
+    Function,
+}
 
-    match defined_in {
-        None => {
-            if checker.initial {
-                return Some(Docstring {
-                    kind: DocstringKind::Module,
-                    parent: None,
-                    expr,
-                });
-            }
-        }
-        Some(parent) => {
-            if let StmtKind::FunctionDef { body, .. }
-            | StmtKind::AsyncFunctionDef { body, .. }
-            | StmtKind::ClassDef { body, .. } = &parent.node
-            {
-                if body.first().map(|node| node == stmt).unwrap_or_default() {
-                    return Some(Docstring {
-                        kind: if matches!(&parent.node, StmtKind::ClassDef { .. }) {
-                            DocstringKind::Class
-                        } else {
-                            DocstringKind::Function
-                        },
-                        parent: None,
-                        expr,
-                    });
+/// Extract a docstring from a function or class body.
+pub fn docstring_from(suite: &[Stmt]) -> Option<&Expr> {
+    if let Some(stmt) = suite.first() {
+        if let StmtKind::Expr { value } = &stmt.node {
+            if matches!(
+                &value.node,
+                ExprKind::Constant {
+                    value: Constant::Str(_),
+                    ..
                 }
+            ) {
+                return Some(value);
             }
         }
     }
-
     None
 }
 
-pub fn one_liner(checker: &mut Checker, docstring: &Docstring) {
-    if let ExprKind::Constant {
-        value: Constant::Str(string),
-        ..
-    } = &docstring.expr.node
-    {
-        let mut line_count = 0;
-        let mut non_empty_line_count = 0;
-        for line in string.lines() {
-            line_count += 1;
-            if !line.trim().is_empty() {
-                non_empty_line_count += 1;
-            }
-            if non_empty_line_count > 1 {
-                return;
-            }
-        }
-
-        if non_empty_line_count == 1 && line_count > 1 {
-            checker.add_check(Check::new(
-                CheckKind::OneLinerDocstring,
-                Range::from_located(docstring.expr),
-            ));
-        }
+/// Extract a `Definition` from the AST node defined by a `Stmt`.
+pub fn extract<'a>(
+    scope: &VisibleScope,
+    stmt: &'a Stmt,
+    body: &'a [Stmt],
+    kind: &Documentable,
+) -> Definition<'a> {
+    let expr = docstring_from(body);
+    match kind {
+        Documentable::Function => match scope {
+            VisibleScope {
+                modifier: Modifier::Module,
+                ..
+            } => Definition {
+                kind: DefinitionKind::Function(stmt),
+                docstring: expr,
+            },
+            VisibleScope {
+                modifier: Modifier::Class,
+                ..
+            } => Definition {
+                kind: DefinitionKind::Method(stmt),
+                docstring: expr,
+            },
+            VisibleScope {
+                modifier: Modifier::Function,
+                ..
+            } => Definition {
+                kind: DefinitionKind::NestedFunction(stmt),
+                docstring: expr,
+            },
+        },
+        Documentable::Class => match scope {
+            VisibleScope {
+                modifier: Modifier::Module,
+                ..
+            } => Definition {
+                kind: DefinitionKind::Class(stmt),
+                docstring: expr,
+            },
+            VisibleScope {
+                modifier: Modifier::Class,
+                ..
+            } => Definition {
+                kind: DefinitionKind::NestedClass(stmt),
+                docstring: expr,
+            },
+            VisibleScope {
+                modifier: Modifier::Function,
+                ..
+            } => Definition {
+                kind: DefinitionKind::NestedClass(stmt),
+                docstring: expr,
+            },
+        },
     }
 }
 
-pub fn blank_after_summary(checker: &mut Checker, docstring: &Docstring) {
-    if let ExprKind::Constant {
-        value: Constant::Str(string),
-        ..
-    } = &docstring.expr.node
-    {
-        let mut lines_count = 1;
-        let mut blanks_count = 0;
-        for line in string.trim().lines().skip(1) {
-            lines_count += 1;
-            if line.trim().is_empty() {
-                blanks_count += 1;
+/// Extract the source code range for a docstring.
+fn range_for(docstring: &Expr) -> Range {
+    // RustPython currently omits the first quotation mark in a string, so offset the location.
+    Range {
+        location: Location::new(docstring.location.row(), docstring.location.column() - 1),
+        end_location: docstring.end_location,
+    }
+}
+
+/// D100, D101, D102, D103, D104, D105, D106, D107
+pub fn not_missing(
+    checker: &mut Checker,
+    definition: &Definition,
+    visibility: &Visibility,
+) -> bool {
+    if matches!(visibility, Visibility::Private) {
+        return true;
+    }
+
+    if definition.docstring.is_some() {
+        return true;
+    }
+
+    match definition.kind {
+        DefinitionKind::Module => {
+            if checker.settings.enabled.contains(&CheckCode::D100) {
+                checker.add_check(Check::new(
+                    CheckKind::PublicModule,
+                    Range {
+                        location: Location::new(1, 1),
+                        end_location: Location::new(1, 1),
+                    },
+                ));
+            }
+            false
+        }
+        DefinitionKind::Package => {
+            if checker.settings.enabled.contains(&CheckCode::D104) {
+                checker.add_check(Check::new(
+                    CheckKind::PublicPackage,
+                    Range {
+                        location: Location::new(1, 1),
+                        end_location: Location::new(1, 1),
+                    },
+                ));
+            }
+            false
+        }
+        DefinitionKind::Class(stmt) => {
+            if checker.settings.enabled.contains(&CheckCode::D101) {
+                checker.add_check(Check::new(
+                    CheckKind::PublicClass,
+                    Range::from_located(stmt),
+                ));
+            }
+            false
+        }
+        DefinitionKind::NestedClass(stmt) => {
+            if checker.settings.enabled.contains(&CheckCode::D106) {
+                checker.add_check(Check::new(
+                    CheckKind::PublicNestedClass,
+                    Range::from_located(stmt),
+                ));
+            }
+            false
+        }
+        DefinitionKind::Function(stmt) | DefinitionKind::NestedFunction(stmt) => {
+            if is_overload(stmt) {
+                true
             } else {
-                break;
+                if checker.settings.enabled.contains(&CheckCode::D103) {
+                    checker.add_check(Check::new(
+                        CheckKind::PublicFunction,
+                        Range::from_located(stmt),
+                    ));
+                }
+                false
             }
         }
-        if lines_count > 1 && blanks_count != 1 {
-            checker.add_check(Check::new(
-                CheckKind::BlankLineAfterSummary,
-                Range::from_located(docstring.expr),
-            ));
+        DefinitionKind::Method(stmt) => {
+            if is_overload(stmt) {
+                true
+            } else if is_magic(stmt) {
+                if checker.settings.enabled.contains(&CheckCode::D105) {
+                    checker.add_check(Check::new(
+                        CheckKind::MagicMethod,
+                        Range::from_located(stmt),
+                    ));
+                }
+                true
+            } else if is_init(stmt) {
+                if checker.settings.enabled.contains(&CheckCode::D107) {
+                    checker.add_check(Check::new(CheckKind::PublicInit, Range::from_located(stmt)));
+                }
+                true
+            } else {
+                if checker.settings.enabled.contains(&CheckCode::D102) {
+                    checker.add_check(Check::new(
+                        CheckKind::PublicMethod,
+                        Range::from_located(stmt),
+                    ));
+                }
+                true
+            }
         }
     }
 }
 
-pub fn newline_after_last_paragraph(checker: &mut Checker, docstring: &Docstring) {
-    if let ExprKind::Constant {
-        value: Constant::Str(string),
-        ..
-    } = &docstring.expr.node
-    {
-        let mut line_count = 0;
-        for line in string.lines() {
-            if !line.trim().is_empty() {
+/// D200
+pub fn one_liner(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = &definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            let mut line_count = 0;
+            let mut non_empty_line_count = 0;
+            for line in string.lines() {
                 line_count += 1;
+                if !line.trim().is_empty() {
+                    non_empty_line_count += 1;
+                }
+                if non_empty_line_count > 1 {
+                    break;
+                }
             }
-            if line_count > 1 {
-                let content = checker
+
+            if non_empty_line_count == 1 && line_count > 1 {
+                checker.add_check(Check::new(CheckKind::FitsOnOneLine, range_for(docstring)));
+            }
+        }
+    }
+}
+
+static COMMENT_REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"^\s*#").unwrap());
+
+static INNER_FUNCTION_OR_CLASS_REGEX: Lazy<Regex> =
+    Lazy::new(|| Regex::new(r"^\s+(?:(?:class|def|async def)\s|@)").unwrap());
+
+/// D201, D202
+pub fn blank_before_after_function(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = definition.docstring {
+        if let DefinitionKind::Function(parent)
+        | DefinitionKind::NestedFunction(parent)
+        | DefinitionKind::Method(parent) = &definition.kind
+        {
+            if let ExprKind::Constant {
+                value: Constant::Str(_),
+                ..
+            } = &docstring.node
+            {
+                let (before, _, after) = checker
                     .locator
-                    .slice_source_code_range(&Range::from_located(docstring.expr));
-                if let Some(line) = content.lines().last() {
-                    let line = line.trim();
-                    if line != "\"\"\"" && line != "'''" {
+                    .partition_source_code_at(&Range::from_located(parent), &range_for(docstring));
+
+                if checker.settings.enabled.contains(&CheckCode::D201) {
+                    let blank_lines_before = before
+                        .lines()
+                        .rev()
+                        .skip(1)
+                        .take_while(|line| line.trim().is_empty())
+                        .count();
+                    if blank_lines_before != 0 {
                         checker.add_check(Check::new(
-                            CheckKind::NewLineAfterLastParagraph,
-                            Range::from_located(docstring.expr),
+                            CheckKind::NoBlankLineBeforeFunction(blank_lines_before),
+                            range_for(docstring),
+                        ));
+                    }
+                }
+
+                if checker.settings.enabled.contains(&CheckCode::D202) {
+                    let blank_lines_after = after
+                        .lines()
+                        .skip(1)
+                        .take_while(|line| line.trim().is_empty())
+                        .count();
+                    let all_blank_after = after
+                        .lines()
+                        .skip(1)
+                        .all(|line| line.trim().is_empty() || COMMENT_REGEX.is_match(line));
+                    // Report a D202 violation if the docstring is followed by a blank line
+                    // and the blank line is not itself followed by an inner function or
+                    // class.
+                    if !all_blank_after
+                        && blank_lines_after != 0
+                        && !(blank_lines_after == 1
+                            && INNER_FUNCTION_OR_CLASS_REGEX.is_match(after))
+                    {
+                        checker.add_check(Check::new(
+                            CheckKind::NoBlankLineAfterFunction(blank_lines_after),
+                            range_for(docstring),
                         ));
                     }
                 }
-                return;
             }
         }
     }
 }
 
-pub fn no_surrounding_whitespace(checker: &mut Checker, docstring: &Docstring) {
-    if let ExprKind::Constant {
-        value: Constant::Str(string),
-        ..
-    } = &docstring.expr.node
-    {
-        let mut lines = string.lines();
-        if let Some(line) = lines.next() {
-            if line.trim().is_empty() {
-                return;
-            }
+/// D203, D204, D211
+pub fn blank_before_after_class(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = &definition.docstring {
+        if let DefinitionKind::Class(parent) | DefinitionKind::NestedClass(parent) =
+            &definition.kind
+        {
+            if let ExprKind::Constant {
+                value: Constant::Str(_),
+                ..
+            } = &docstring.node
+            {
+                let (before, _, after) = checker
+                    .locator
+                    .partition_source_code_at(&Range::from_located(parent), &range_for(docstring));
 
-            if line.starts_with(' ') || (matches!(lines.next(), None) && line.ends_with(' ')) {
+                if checker.settings.enabled.contains(&CheckCode::D203)
+                    || checker.settings.enabled.contains(&CheckCode::D211)
+                {
+                    let blank_lines_before = before
+                        .lines()
+                        .rev()
+                        .skip(1)
+                        .take_while(|line| line.trim().is_empty())
+                        .count();
+                    if blank_lines_before != 0
+                        && checker.settings.enabled.contains(&CheckCode::D211)
+                    {
+                        checker.add_check(Check::new(
+                            CheckKind::NoBlankLineBeforeClass(blank_lines_before),
+                            range_for(docstring),
+                        ));
+                    }
+                    if blank_lines_before != 1
+                        && checker.settings.enabled.contains(&CheckCode::D203)
+                    {
+                        checker.add_check(Check::new(
+                            CheckKind::OneBlankLineBeforeClass(blank_lines_before),
+                            range_for(docstring),
+                        ));
+                    }
+                }
+
+                if checker.settings.enabled.contains(&CheckCode::D204) {
+                    let blank_lines_after = after
+                        .lines()
+                        .skip(1)
+                        .take_while(|line| line.trim().is_empty())
+                        .count();
+                    let all_blank_after = after
+                        .lines()
+                        .skip(1)
+                        .all(|line| line.trim().is_empty() || COMMENT_REGEX.is_match(line));
+                    if !all_blank_after && blank_lines_after != 1 {
+                        checker.add_check(Check::new(
+                            CheckKind::OneBlankLineAfterClass(blank_lines_after),
+                            range_for(docstring),
+                        ));
+                    }
+                }
+            }
+        }
+    }
+}
+
+/// D205
+pub fn blank_after_summary(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            let mut lines_count = 1;
+            let mut blanks_count = 0;
+            for line in string.trim().lines().skip(1) {
+                lines_count += 1;
+                if line.trim().is_empty() {
+                    blanks_count += 1;
+                } else {
+                    break;
+                }
+            }
+            if lines_count > 1 && blanks_count != 1 {
                 checker.add_check(Check::new(
-                    CheckKind::NoSurroundingWhitespace,
-                    Range::from_located(docstring.expr),
+                    CheckKind::NoBlankLineAfterSummary,
+                    range_for(docstring),
                 ));
             }
         }
     }
 }
 
-pub fn not_empty(checker: &mut Checker, docstring: &Docstring) {
-    if let ExprKind::Constant {
-        value: Constant::Str(string),
-        ..
-    } = &docstring.expr.node
-    {
-        if string.trim().is_empty() {
-            checker.add_check(Check::new(
-                CheckKind::EmptyDocstring,
-                Range::from_located(docstring.expr),
-            ));
+/// D209
+pub fn newline_after_last_paragraph(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            let mut line_count = 0;
+            for line in string.lines() {
+                if !line.trim().is_empty() {
+                    line_count += 1;
+                }
+                if line_count > 1 {
+                    let content = checker
+                        .locator
+                        .slice_source_code_range(&range_for(docstring));
+                    if let Some(line) = content.lines().last() {
+                        let line = line.trim();
+                        if line != "\"\"\"" && line != "'''" {
+                            checker.add_check(Check::new(
+                                CheckKind::NewLineAfterLastParagraph,
+                                range_for(docstring),
+                            ));
+                        }
+                    }
+                    return;
+                }
+            }
         }
     }
 }
 
-pub fn ends_with_period(checker: &mut Checker, docstring: &Docstring) {
-    if let ExprKind::Constant {
-        value: Constant::Str(string),
-        ..
-    } = &docstring.expr.node
-    {
-        if let Some(string) = string.lines().next() {
-            if !string.ends_with('.') {
+/// D210
+pub fn no_surrounding_whitespace(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            let mut lines = string.lines();
+            if let Some(line) = lines.next() {
+                if line.trim().is_empty() {
+                    return;
+                }
+                if line.starts_with(' ') || (matches!(lines.next(), None) && line.ends_with(' ')) {
+                    checker.add_check(Check::new(
+                        CheckKind::NoSurroundingWhitespace,
+                        range_for(docstring),
+                    ));
+                }
+            }
+        }
+    }
+}
+
+/// D212, D213
+pub fn multi_line_summary_start(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            if string.lines().nth(1).is_some() {
+                let content = checker
+                    .locator
+                    .slice_source_code_range(&range_for(docstring));
+                if let Some(first_line) = content.lines().next() {
+                    let first_line = first_line.trim();
+                    if first_line == "\"\"\"" || first_line == "'''" {
+                        if checker.settings.enabled.contains(&CheckCode::D212) {
+                            checker.add_check(Check::new(
+                                CheckKind::MultiLineSummaryFirstLine,
+                                range_for(docstring),
+                            ));
+                        }
+                    } else if checker.settings.enabled.contains(&CheckCode::D213) {
+                        checker.add_check(Check::new(
+                            CheckKind::MultiLineSummarySecondLine,
+                            range_for(docstring),
+                        ));
+                    }
+                }
+            }
+        }
+    }
+}
+
+/// D300
+pub fn triple_quotes(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            let content = checker
+                .locator
+                .slice_source_code_range(&range_for(docstring));
+            if string.contains("\"\"\"") {
+                if !content.starts_with("'''") {
+                    checker.add_check(Check::new(
+                        CheckKind::UsesTripleQuotes,
+                        range_for(docstring),
+                    ));
+                }
+            } else if !content.starts_with("\"\"\"") {
                 checker.add_check(Check::new(
-                    CheckKind::DocstringEndsInNonPeriod,
-                    Range::from_located(docstring.expr),
+                    CheckKind::UsesTripleQuotes,
+                    range_for(docstring),
                 ));
             }
         }
     }
 }
+
+/// D400
+pub fn ends_with_period(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            if let Some(string) = string.lines().next() {
+                if !string.ends_with('.') {
+                    checker.add_check(Check::new(CheckKind::EndsInPeriod, range_for(docstring)));
+                }
+            }
+        }
+    }
+}
+
+/// D402
+pub fn no_signature(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = definition.docstring {
+        if let DefinitionKind::Function(parent)
+        | DefinitionKind::NestedFunction(parent)
+        | DefinitionKind::Method(parent) = definition.kind
+        {
+            if let StmtKind::FunctionDef { name, .. } = &parent.node {
+                if let ExprKind::Constant {
+                    value: Constant::Str(string),
+                    ..
+                } = &docstring.node
+                {
+                    if let Some(first_line) = string.lines().next() {
+                        if first_line.contains(&format!("{name}(")) {
+                            checker.add_check(Check::new(
+                                CheckKind::NoSignature,
+                                range_for(docstring),
+                            ));
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+/// D403
+pub fn capitalized(checker: &mut Checker, definition: &Definition) {
+    if !matches!(definition.kind, DefinitionKind::Function(_)) {
+        return;
+    }
+
+    if let Some(docstring) = definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            if let Some(first_word) = string.split(' ').next() {
+                if first_word == first_word.to_uppercase() {
+                    return;
+                }
+                for char in first_word.chars() {
+                    if !char.is_ascii_alphabetic() && char != '\'' {
+                        return;
+                    }
+                }
+                if let Some(first_char) = first_word.chars().next() {
+                    if !first_char.is_uppercase() {
+                        checker.add_check(Check::new(
+                            CheckKind::FirstLineCapitalized,
+                            range_for(docstring),
+                        ));
+                    }
+                }
+            }
+        }
+    }
+}
+
+/// D415
+pub fn ends_with_punctuation(checker: &mut Checker, definition: &Definition) {
+    if let Some(docstring) = definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            if let Some(string) = string.lines().next() {
+                if !(string.ends_with('.') || string.ends_with('!') || string.ends_with('?')) {
+                    checker.add_check(Check::new(
+                        CheckKind::EndsInPunctuation,
+                        range_for(docstring),
+                    ));
+                }
+            }
+        }
+    }
+}
+
+/// D419
+pub fn not_empty(checker: &mut Checker, definition: &Definition) -> bool {
+    if let Some(docstring) = definition.docstring {
+        if let ExprKind::Constant {
+            value: Constant::Str(string),
+            ..
+        } = &docstring.node
+        {
+            if string.trim().is_empty() {
+                if checker.settings.enabled.contains(&CheckCode::D419) {
+                    checker.add_check(Check::new(CheckKind::NonEmpty, range_for(docstring)));
+                }
+                return false;
+            }
+        }
+    }
+    true
+}

src/lib.rs

@@ -28,6 +28,7 @@ pub mod printer;
 pub mod pyproject;
 mod python;
 pub mod settings;
+pub mod visibility;
 
 /// Run ruff over Python source code directly.
 pub fn check(path: &Path, contents: &str) -> Result<Vec<Message>> {

src/linter.rs

@@ -83,6 +83,36 @@ pub(crate) fn check_path(
     Ok(checks)
 }
 
+pub fn lint_stdin(path: &Path, stdin: &str, settings: &Settings) -> Result<Vec<Message>> {
+    // Tokenize once.
+    let tokens: Vec<LexResult> = tokenize(stdin);
+
+    // Determine the noqa line for every line in the source.
+    let noqa_line_for = noqa::extract_noqa_line_for(&tokens);
+
+    // Generate checks.
+    let checks = check_path(
+        path,
+        stdin,
+        tokens,
+        &noqa_line_for,
+        settings,
+        &fixer::Mode::None,
+    )?;
+
+    // Convert to messages.
+    Ok(checks
+        .into_iter()
+        .map(|check| Message {
+            kind: check.kind,
+            fixed: check.fix.map(|fix| fix.applied).unwrap_or_default(),
+            location: check.location,
+            end_location: check.end_location,
+            filename: path.to_string_lossy().to_string(),
+        })
+        .collect())
+}
+
 pub fn lint_path(
     path: &Path,
     settings: &Settings,
@@ -966,6 +996,18 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn c414() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/C414.py"),
+            &settings::Settings::for_rule(CheckCode::C414),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
     #[test]
     fn c415() -> Result<()> {
         let mut checks = check_path(
@@ -979,10 +1021,142 @@ mod tests {
     }
 
     #[test]
-    fn d200() -> Result<()> {
+    fn d100() -> Result<()> {
         let mut checks = check_path(
             Path::new("./resources/test/fixtures/D.py"),
-            &settings::Settings::for_rule(CheckCode::D200),
+            &settings::Settings::for_rule(CheckCode::D100),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d101() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D101),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d102() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D102),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d103() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D103),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d104() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D104),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d105() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D105),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d106() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D106),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d107() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D107),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d201() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D201),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d202() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D202),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d203() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D203),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d204() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D204),
             &fixer::Mode::Generate,
         )?;
         checks.sort_by_key(|check| check.location);
@@ -1026,6 +1200,54 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn d211() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D211),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d212() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D212),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d213() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D213),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d300() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D300),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
     #[test]
     fn d400() -> Result<()> {
         let mut checks = check_path(
@@ -1038,6 +1260,42 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn d402() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D402),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d403() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D403),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
+    #[test]
+    fn d415() -> Result<()> {
+        let mut checks = check_path(
+            Path::new("./resources/test/fixtures/D.py"),
+            &settings::Settings::for_rule(CheckCode::D415),
+            &fixer::Mode::Generate,
+        )?;
+        checks.sort_by_key(|check| check.location);
+        insta::assert_yaml_snapshot!(checks);
+        Ok(())
+    }
+
     #[test]
     fn d419() -> Result<()> {
         let mut checks = check_path(

src/main.rs

@@ -1,4 +1,4 @@
-use std::io;
+use std::io::{self, Read};
 use std::path::{Path, PathBuf};
 use std::process::ExitCode;
 use std::sync::mpsc::channel;
@@ -19,7 +19,7 @@ use ruff::cli::{warn_on, Cli, Warnable};
 use ruff::fs::iter_python_files;
 use ruff::linter::add_noqa_to_path;
 use ruff::linter::autoformat_path;
-use ruff::linter::lint_path;
+use ruff::linter::{lint_path, lint_stdin};
 use ruff::logging::set_up_logging;
 use ruff::message::Message;
 use ruff::printer::{Printer, SerializationFormat};
@@ -75,6 +75,19 @@ fn show_files(files: &[PathBuf], settings: &Settings) {
     }
 }
 
+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) -> Result<Vec<Message>> {
+    let stdin = read_from_stdin()?;
+    let mut messages = lint_stdin(filename, &stdin, settings)?;
+    messages.sort_unstable();
+    Ok(messages)
+}
+
 fn run_once(
     files: &[PathBuf],
     settings: &Settings,
@@ -352,7 +365,17 @@ fn inner_main() -> Result<ExitCode> {
             println!("Formatted {modifications} files.");
         }
     } else {
-        let messages = run_once(&cli.files, &settings, !cli.no_cache, cli.fix)?;
+        let messages = if cli.files == vec![PathBuf::from("-")] {
+            if cli.fix {
+                eprintln!("Warning: --fix is not enabled when reading from stdin.");
+            }
+
+            let filename = cli.stdin_filename.unwrap_or_else(|| "-".to_string());
+            let path = Path::new(&filename);
+            run_once_stdin(&settings, path)?
+        } else {
+            run_once(&cli.files, &settings, !cli.no_cache, cli.fix)?
+        };
         if !cli.quiet {
             printer.write_once(&messages)?;
         }

src/snapshots/ruff__linter__tests__c414.snap

@@ -0,0 +1,148 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - list
+      - list
+  location:
+    row: 2
+    column: 1
+  end_location:
+    row: 2
+    column: 14
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - tuple
+      - list
+  location:
+    row: 3
+    column: 1
+  end_location:
+    row: 3
+    column: 15
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - list
+      - tuple
+  location:
+    row: 4
+    column: 1
+  end_location:
+    row: 4
+    column: 15
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - tuple
+      - tuple
+  location:
+    row: 5
+    column: 1
+  end_location:
+    row: 5
+    column: 16
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - set
+      - set
+  location:
+    row: 6
+    column: 1
+  end_location:
+    row: 6
+    column: 12
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - list
+      - set
+  location:
+    row: 7
+    column: 1
+  end_location:
+    row: 7
+    column: 13
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - tuple
+      - set
+  location:
+    row: 8
+    column: 1
+  end_location:
+    row: 8
+    column: 14
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - sorted
+      - set
+  location:
+    row: 9
+    column: 1
+  end_location:
+    row: 9
+    column: 15
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - reversed
+      - set
+  location:
+    row: 10
+    column: 1
+  end_location:
+    row: 10
+    column: 17
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - list
+      - sorted
+  location:
+    row: 11
+    column: 1
+  end_location:
+    row: 11
+    column: 16
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - tuple
+      - sorted
+  location:
+    row: 12
+    column: 1
+  end_location:
+    row: 12
+    column: 17
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - sorted
+      - sorted
+  location:
+    row: 13
+    column: 1
+  end_location:
+    row: 13
+    column: 18
+  fix: ~
+- kind:
+    UnnecessaryDoubleCastOrProcess:
+      - reversed
+      - sorted
+  location:
+    row: 14
+    column: 1
+  end_location:
+    row: 14
+    column: 20
+  fix: ~
+

src/snapshots/ruff__linter__tests__d100.snap

@@ -0,0 +1,13 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: PublicModule
+  location:
+    row: 1
+    column: 1
+  end_location:
+    row: 1
+    column: 1
+  fix: ~
+

src/snapshots/ruff__linter__tests__d101.snap

@@ -0,0 +1,13 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: PublicClass
+  location:
+    row: 14
+    column: 1
+  end_location:
+    row: 67
+    column: 1
+  fix: ~
+

src/snapshots/ruff__linter__tests__d102.snap

@@ -0,0 +1,29 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: PublicMethod
+  location:
+    row: 22
+    column: 5
+  end_location:
+    row: 25
+    column: 5
+  fix: ~
+- kind: PublicMethod
+  location:
+    row: 51
+    column: 5
+  end_location:
+    row: 54
+    column: 5
+  fix: ~
+- kind: PublicMethod
+  location:
+    row: 63
+    column: 5
+  end_location:
+    row: 67
+    column: 1
+  fix: ~
+

src/snapshots/ruff__linter__tests__d103.snap

@@ -0,0 +1,13 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: PublicFunction
+  location:
+    row: 395
+    column: 1
+  end_location:
+    row: 396
+    column: 1
+  fix: ~
+

src/snapshots/ruff__linter__tests__d104.snap

@@ -0,0 +1,6 @@
+---
+source: src/linter.rs
+expression: checks
+---
+[]
+

src/snapshots/ruff__linter__tests__d105.snap

@@ -0,0 +1,13 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: MagicMethod
+  location:
+    row: 59
+    column: 5
+  end_location:
+    row: 62
+    column: 5
+  fix: ~
+

src/snapshots/ruff__linter__tests__d106.snap

@@ -0,0 +1,6 @@
+---
+source: src/linter.rs
+expression: checks
+---
+[]
+

src/snapshots/ruff__linter__tests__d107.snap

@@ -0,0 +1,21 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: PublicInit
+  location:
+    row: 55
+    column: 5
+  end_location:
+    row: 58
+    column: 5
+  fix: ~
+- kind: PublicInit
+  location:
+    row: 529
+    column: 5
+  end_location:
+    row: 533
+    column: 1
+  fix: ~
+

src/snapshots/ruff__linter__tests__d200.snap

@@ -2,10 +2,10 @@
 source: src/linter.rs
 expression: checks
 ---
-- kind: OneLinerDocstring
+- kind: FitsOnOneLine
   location:
     row: 124
-    column: 6
+    column: 5
   end_location:
     row: 126
     column: 8

src/snapshots/ruff__linter__tests__d201.snap

@@ -0,0 +1,23 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    NoBlankLineBeforeFunction: 1
+  location:
+    row: 132
+    column: 5
+  end_location:
+    row: 132
+    column: 25
+  fix: ~
+- kind:
+    NoBlankLineBeforeFunction: 1
+  location:
+    row: 146
+    column: 5
+  end_location:
+    row: 146
+    column: 38
+  fix: ~
+

src/snapshots/ruff__linter__tests__d202.snap

@@ -0,0 +1,23 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    NoBlankLineAfterFunction: 1
+  location:
+    row: 137
+    column: 5
+  end_location:
+    row: 137
+    column: 25
+  fix: ~
+- kind:
+    NoBlankLineAfterFunction: 1
+  location:
+    row: 146
+    column: 5
+  end_location:
+    row: 146
+    column: 38
+  fix: ~
+

src/snapshots/ruff__linter__tests__d203.snap

@@ -0,0 +1,32 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    OneBlankLineBeforeClass: 0
+  location:
+    row: 156
+    column: 5
+  end_location:
+    row: 156
+    column: 33
+  fix: ~
+- kind:
+    OneBlankLineBeforeClass: 0
+  location:
+    row: 187
+    column: 5
+  end_location:
+    row: 187
+    column: 46
+  fix: ~
+- kind:
+    OneBlankLineBeforeClass: 0
+  location:
+    row: 521
+    column: 5
+  end_location:
+    row: 527
+    column: 8
+  fix: ~
+

src/snapshots/ruff__linter__tests__d204.snap

@@ -0,0 +1,23 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    OneBlankLineAfterClass: 0
+  location:
+    row: 176
+    column: 5
+  end_location:
+    row: 176
+    column: 25
+  fix: ~
+- kind:
+    OneBlankLineAfterClass: 0
+  location:
+    row: 187
+    column: 5
+  end_location:
+    row: 187
+    column: 46
+  fix: ~
+

src/snapshots/ruff__linter__tests__d205.snap

@@ -2,18 +2,18 @@
 source: src/linter.rs
 expression: checks
 ---
-- kind: BlankLineAfterSummary
+- kind: NoBlankLineAfterSummary
   location:
     row: 195
-    column: 6
+    column: 5
   end_location:
     row: 198
     column: 8
   fix: ~
-- kind: BlankLineAfterSummary
+- kind: NoBlankLineAfterSummary
   location:
     row: 205
-    column: 6
+    column: 5
   end_location:
     row: 210
     column: 8

src/snapshots/ruff__linter__tests__d209.snap

@@ -5,7 +5,7 @@ expression: checks
 - kind: NewLineAfterLastParagraph
   location:
     row: 276
-    column: 6
+    column: 5
   end_location:
     row: 278
     column: 20

src/snapshots/ruff__linter__tests__d210.snap

@@ -5,7 +5,7 @@ expression: checks
 - kind: NoSurroundingWhitespace
   location:
     row: 283
-    column: 6
+    column: 5
   end_location:
     row: 283
     column: 34
@@ -13,7 +13,7 @@ expression: checks
 - kind: NoSurroundingWhitespace
   location:
     row: 288
-    column: 6
+    column: 5
   end_location:
     row: 288
     column: 38
@@ -21,7 +21,7 @@ expression: checks
 - kind: NoSurroundingWhitespace
   location:
     row: 294
-    column: 6
+    column: 5
   end_location:
     row: 297
     column: 8

src/snapshots/ruff__linter__tests__d211.snap

@@ -0,0 +1,23 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind:
+    NoBlankLineBeforeClass: 1
+  location:
+    row: 165
+    column: 5
+  end_location:
+    row: 165
+    column: 30
+  fix: ~
+- kind:
+    NoBlankLineBeforeClass: 1
+  location:
+    row: 176
+    column: 5
+  end_location:
+    row: 176
+    column: 25
+  fix: ~
+

src/snapshots/ruff__linter__tests__d212.snap

@@ -0,0 +1,13 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: MultiLineSummaryFirstLine
+  location:
+    row: 124
+    column: 5
+  end_location:
+    row: 126
+    column: 8
+  fix: ~
+

src/snapshots/ruff__linter__tests__d213.snap

@@ -0,0 +1,133 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 195
+    column: 5
+  end_location:
+    row: 198
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 205
+    column: 5
+  end_location:
+    row: 210
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 215
+    column: 5
+  end_location:
+    row: 219
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 225
+    column: 5
+  end_location:
+    row: 229
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 235
+    column: 5
+  end_location:
+    row: 239
+    column: 4
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 245
+    column: 5
+  end_location:
+    row: 249
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 255
+    column: 5
+  end_location:
+    row: 259
+    column: 12
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 265
+    column: 5
+  end_location:
+    row: 269
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 276
+    column: 5
+  end_location:
+    row: 278
+    column: 20
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 294
+    column: 5
+  end_location:
+    row: 297
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 338
+    column: 5
+  end_location:
+    row: 343
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 378
+    column: 5
+  end_location:
+    row: 381
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 387
+    column: 5
+  end_location:
+    row: 391
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 433
+    column: 37
+  end_location:
+    row: 436
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 445
+    column: 5
+  end_location:
+    row: 449
+    column: 8
+  fix: ~
+- kind: MultiLineSummarySecondLine
+  location:
+    row: 521
+    column: 5
+  end_location:
+    row: 527
+    column: 8
+  fix: ~
+

src/snapshots/ruff__linter__tests__d300.snap

@@ -0,0 +1,45 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: UsesTripleQuotes
+  location:
+    row: 302
+    column: 6
+  end_location:
+    row: 302
+    column: 20
+  fix: ~
+- kind: UsesTripleQuotes
+  location:
+    row: 307
+    column: 6
+  end_location:
+    row: 307
+    column: 20
+  fix: ~
+- kind: UsesTripleQuotes
+  location:
+    row: 312
+    column: 6
+  end_location:
+    row: 312
+    column: 16
+  fix: ~
+- kind: UsesTripleQuotes
+  location:
+    row: 317
+    column: 6
+  end_location:
+    row: 317
+    column: 16
+  fix: ~
+- kind: UsesTripleQuotes
+  location:
+    row: 323
+    column: 6
+  end_location:
+    row: 323
+    column: 17
+  fix: ~
+

src/snapshots/ruff__linter__tests__d400.snap

@@ -2,138 +2,130 @@
 source: src/linter.rs
 expression: checks
 ---
-- kind: DocstringEndsInNonPeriod
-  location:
-    row: 69
-    column: 6
-  end_location:
-    row: 69
-    column: 12
-  fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 124
-    column: 6
+    column: 5
   end_location:
     row: 126
     column: 8
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 283
-    column: 6
+    column: 5
   end_location:
     row: 283
     column: 34
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 288
-    column: 6
+    column: 5
   end_location:
     row: 288
     column: 38
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 350
-    column: 6
+    column: 5
   end_location:
     row: 350
     column: 18
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 401
-    column: 26
+    column: 25
   end_location:
     row: 401
     column: 40
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 405
-    column: 6
+    column: 5
   end_location:
     row: 405
     column: 25
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 411
-    column: 6
+    column: 5
   end_location:
     row: 411
     column: 25
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 417
-    column: 36
+    column: 35
   end_location:
     row: 417
     column: 50
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 424
-    column: 50
+    column: 49
   end_location:
     row: 424
     column: 64
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 465
-    column: 6
+    column: 5
   end_location:
     row: 465
     column: 25
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 470
-    column: 6
+    column: 5
   end_location:
     row: 470
     column: 25
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 475
-    column: 6
+    column: 5
   end_location:
     row: 475
     column: 25
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 482
-    column: 6
+    column: 5
   end_location:
     row: 482
     column: 25
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 504
-    column: 6
+    column: 5
   end_location:
     row: 504
     column: 35
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 509
-    column: 6
+    column: 5
   end_location:
     row: 509
     column: 34
   fix: ~
-- kind: DocstringEndsInNonPeriod
+- kind: EndsInPeriod
   location:
     row: 515
-    column: 6
+    column: 5
   end_location:
     row: 515
     column: 33

src/snapshots/ruff__linter__tests__d402.snap

@@ -0,0 +1,13 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: NoSignature
+  location:
+    row: 373
+    column: 5
+  end_location:
+    row: 373
+    column: 31
+  fix: ~
+

src/snapshots/ruff__linter__tests__d403.snap

@@ -0,0 +1,6 @@
+---
+source: src/linter.rs
+expression: checks
+---
+[]
+

src/snapshots/ruff__linter__tests__d415.snap

@@ -0,0 +1,125 @@
+---
+source: src/linter.rs
+expression: checks
+---
+- kind: EndsInPunctuation
+  location:
+    row: 124
+    column: 5
+  end_location:
+    row: 126
+    column: 8
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 283
+    column: 5
+  end_location:
+    row: 283
+    column: 34
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 288
+    column: 5
+  end_location:
+    row: 288
+    column: 38
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 350
+    column: 5
+  end_location:
+    row: 350
+    column: 18
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 401
+    column: 25
+  end_location:
+    row: 401
+    column: 40
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 405
+    column: 5
+  end_location:
+    row: 405
+    column: 25
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 411
+    column: 5
+  end_location:
+    row: 411
+    column: 25
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 417
+    column: 35
+  end_location:
+    row: 417
+    column: 50
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 424
+    column: 49
+  end_location:
+    row: 424
+    column: 64
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 465
+    column: 5
+  end_location:
+    row: 465
+    column: 25
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 470
+    column: 5
+  end_location:
+    row: 470
+    column: 25
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 475
+    column: 5
+  end_location:
+    row: 475
+    column: 25
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 482
+    column: 5
+  end_location:
+    row: 482
+    column: 25
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 504
+    column: 5
+  end_location:
+    row: 504
+    column: 35
+  fix: ~
+- kind: EndsInPunctuation
+  location:
+    row: 515
+    column: 5
+  end_location:
+    row: 515
+    column: 33
+  fix: ~
+

src/snapshots/ruff__linter__tests__d419.snap

@@ -2,26 +2,26 @@
 source: src/linter.rs
 expression: checks
 ---
-- kind: EmptyDocstring
+- kind: NonEmpty
   location:
     row: 19
-    column: 10
+    column: 9
   end_location:
     row: 19
     column: 15
   fix: ~
-- kind: EmptyDocstring
+- kind: NonEmpty
   location:
     row: 69
-    column: 6
+    column: 5
   end_location:
     row: 69
     column: 12
   fix: ~
-- kind: EmptyDocstring
+- kind: NonEmpty
   location:
     row: 75
-    column: 10
+    column: 9
   end_location:
     row: 75
     column: 11

src/visibility.rs

@@ -0,0 +1,149 @@
+use std::path::Path;
+
+use crate::ast::helpers::match_name_or_attr;
+use rustpython_ast::{Stmt, StmtKind};
+
+use crate::docstrings::Documentable;
+
+#[derive(Debug, Clone)]
+pub enum Modifier {
+    Module,
+    Class,
+    Function,
+}
+
+#[derive(Debug, Clone)]
+pub enum Visibility {
+    Public,
+    Private,
+}
+
+#[derive(Debug, Clone)]
+pub struct VisibleScope {
+    pub modifier: Modifier,
+    pub visibility: Visibility,
+}
+
+pub fn is_overload(stmt: &Stmt) -> bool {
+    match &stmt.node {
+        StmtKind::FunctionDef { decorator_list, .. }
+        | StmtKind::AsyncFunctionDef { decorator_list, .. } => decorator_list
+            .iter()
+            .any(|expr| match_name_or_attr(expr, "overload")),
+        _ => panic!("Found non-FunctionDef in is_overload"),
+    }
+}
+
+pub fn is_magic(stmt: &Stmt) -> bool {
+    match &stmt.node {
+        StmtKind::FunctionDef { name, .. } | StmtKind::AsyncFunctionDef { name, .. } => {
+            name.starts_with("__")
+                && name.ends_with("__")
+                && name != "__init__"
+                && name != "__call__"
+                && name != "__new__"
+        }
+        _ => panic!("Found non-FunctionDef in is_magic"),
+    }
+}
+
+pub fn is_init(stmt: &Stmt) -> bool {
+    match &stmt.node {
+        StmtKind::FunctionDef { name, .. } | StmtKind::AsyncFunctionDef { name, .. } => {
+            name == "__init__"
+        }
+        _ => panic!("Found non-FunctionDef in is_init"),
+    }
+}
+
+fn is_private_name(module_name: &str) -> bool {
+    module_name.starts_with('_') || (module_name.starts_with("__") && module_name.ends_with("__"))
+}
+
+pub fn module_visibility(path: &Path) -> Visibility {
+    for component in path.iter().rev() {
+        if is_private_name(&component.to_string_lossy()) {
+            return Visibility::Private;
+        }
+    }
+    Visibility::Public
+}
+
+fn function_visibility(stmt: &Stmt) -> Visibility {
+    match &stmt.node {
+        StmtKind::FunctionDef { name, .. } | StmtKind::AsyncFunctionDef { name, .. } => {
+            if name.starts_with('_') {
+                Visibility::Private
+            } else {
+                Visibility::Public
+            }
+        }
+        _ => panic!("Found non-FunctionDef in function_visibility"),
+    }
+}
+
+fn method_visibility(stmt: &Stmt) -> Visibility {
+    match &stmt.node {
+        StmtKind::FunctionDef { name, .. } | StmtKind::AsyncFunctionDef { name, .. } => {
+            // Is the method non-private?
+            if !name.starts_with('_') {
+                return Visibility::Public;
+            }
+
+            // Is this a magic method?
+            if name.starts_with("__") && name.ends_with("__") {
+                return Visibility::Public;
+            }
+
+            Visibility::Private
+        }
+        _ => panic!("Found non-FunctionDef in method_visibility"),
+    }
+}
+
+fn class_visibility(stmt: &Stmt) -> Visibility {
+    match &stmt.node {
+        StmtKind::ClassDef { name, .. } => {
+            if name.starts_with('_') {
+                Visibility::Private
+            } else {
+                Visibility::Public
+            }
+        }
+        _ => panic!("Found non-ClassDef in function_visibility"),
+    }
+}
+
+/// Transition a `VisibleScope` based on a new `Documentable` definition.
+pub fn transition_scope(scope: &VisibleScope, stmt: &Stmt, kind: &Documentable) -> VisibleScope {
+    match kind {
+        Documentable::Function => VisibleScope {
+            modifier: Modifier::Function,
+            visibility: match scope {
+                VisibleScope {
+                    modifier: Modifier::Module,
+                    visibility: Visibility::Public,
+                } => function_visibility(stmt),
+                VisibleScope {
+                    modifier: Modifier::Class,
+                    visibility: Visibility::Public,
+                } => method_visibility(stmt),
+                _ => Visibility::Private,
+            },
+        },
+        Documentable::Class => VisibleScope {
+            modifier: Modifier::Class,
+            visibility: match scope {
+                VisibleScope {
+                    modifier: Modifier::Module,
+                    visibility: Visibility::Public,
+                } => class_visibility(stmt),
+                VisibleScope {
+                    modifier: Modifier::Class,
+                    visibility: Visibility::Public,
+                } => class_visibility(stmt),
+                _ => Visibility::Private,
+            },
+        },
+    }
+}

tests/integration_test.rs

@@ -0,0 +1,47 @@
+use std::str;
+
+use anyhow::Result;
+use assert_cmd::{crate_name, Command};
+
+#[test]
+fn test_stdin_success() -> Result<()> {
+    let mut cmd = Command::cargo_bin(crate_name!())?;
+    cmd.args(&["-"]).write_stdin("").assert().success();
+    Ok(())
+}
+
+#[test]
+fn test_stdin_error() -> Result<()> {
+    let mut cmd = Command::cargo_bin(crate_name!())?;
+    let output = cmd
+        .args(&["-"])
+        .write_stdin("import os\n")
+        .assert()
+        .failure();
+    assert!(str::from_utf8(&output.get_output().stdout)?.contains("-:1:1: F401"));
+    Ok(())
+}
+
+#[test]
+fn test_stdin_filename() -> Result<()> {
+    let mut cmd = Command::cargo_bin(crate_name!())?;
+    let output = cmd
+        .args(&["-", "--stdin-filename", "F401.py"])
+        .write_stdin("import os\n")
+        .assert()
+        .failure();
+    assert!(str::from_utf8(&output.get_output().stdout)?.contains("F401.py:1:1: F401"));
+    Ok(())
+}
+
+#[test]
+fn test_stdin_autofix() -> Result<()> {
+    let mut cmd = Command::cargo_bin(crate_name!())?;
+    let output = cmd
+        .args(&["-", "--fix"])
+        .write_stdin("import os\n")
+        .assert()
+        .failure();
+    assert!(str::from_utf8(&output.get_output().stdout)?.contains("-:1:1: F401"));
+    Ok(())
+}