Update rule docs for preview feature

## Summary

This is a follow-up PR to #11445 update the `E27` rules to consider soft
keywords as well.

## Test Plan

Add test cases consisting of soft keywords and update the snapshot.

.github/workflows/ci.yaml

@@ -167,6 +167,9 @@ jobs:
       - uses: Swatinem/rust-cache@v2
       - name: "Run tests"
         shell: bash
+        env:
+          # Workaround for <https://github.com/nextest-rs/nextest/issues/1493>.
+          RUSTUP_WINDOWS_PATH_ADD_BIN: 1
         run: |
           cargo nextest run --all-features --profile ci
           cargo test --all-features --doc

crates/ruff_linter/resources/test/fixtures/flake8_bugbear/B018.py

@@ -6,8 +6,8 @@ class Foo2:
     """abc"""
 
     a = 2
-    "str"  # Str (no raise)
-    f"{int}"  # JoinedStr (no raise)
+    "str"  # StringLiteral
+    f"{int}"  # FString
     1j  # Number (complex)
     1  # Number (int)
     1.0  # Number (float)
@@ -34,8 +34,8 @@ def foo1():
 def foo2():
     """my docstring"""
     a = 2
-    "str"  # Str (no raise)
-    f"{int}"  # JoinedStr (no raise)
+    "str"  # StringLiteral
+    f"{int}"  # FString
     1j  # Number (complex)
     1  # Number (int)
     1.0  # Number (float)

crates/ruff_linter/resources/test/fixtures/flake8_bugbear/B018_attribute_docstring.py

@@ -0,0 +1,93 @@
+# These test cases not only check for `B018` but also verifies that the semantic model
+# correctly identifies certain strings as attribute docstring. And, by way of not
+# raising the `B018` violation, it can be verified.
+
+a: int
+"a: docstring"
+
+b = 1
+"b: docstring" " continue"
+"b: not a docstring"
+
+c: int = 1
+"c: docstring"
+
+_a: int
+"_a: docstring"
+
+if True:
+    d = 1
+    "d: not a docstring"
+
+(e := 1)
+"e: not a docstring"
+
+f = 0
+f += 1
+"f: not a docstring"
+
+g.h = 1
+"g.h: not a docstring"
+
+(i) = 1
+"i: docstring"
+
+(j): int = 1
+"j: docstring"
+
+(k): int
+"k: docstring"
+
+l = m = 1
+"l m: not a docstring"
+
+n.a = n.b = n.c = 1
+"n.*: not a docstring"
+
+(o, p) = (1, 2)
+"o p: not a docstring"
+
+[q, r] = [1, 2]
+"q r: not a docstring"
+
+*s = 1
+"s: not a docstring"
+
+
+class Foo:
+    a = 1
+    "Foo.a: docstring"
+
+    b: int
+    "Foo.b: docstring"
+    "Foo.b: not a docstring"
+
+    c: int = 1
+    "Foo.c: docstring"
+
+    def __init__(self) -> None:
+        # This is actually a docstring but we currently don't detect it.
+        self.x = 1
+        "self.x: not a docstring"
+
+        t = 2
+        "t: not a docstring"
+
+    def random(self):
+        self.y = 2
+        "self.y: not a docstring"
+
+        u = 2
+        "u: not a docstring"
+
+    def add(self, y: int):
+        self.x += y
+
+
+def function():
+    v = 2
+    "v: not a docstring"
+
+
+function.a = 1
+"function.a: not a docstring"

crates/ruff_linter/resources/test/fixtures/pycodestyle/E27.py

@@ -63,3 +63,16 @@ if (a and
 #: Okay
 def f():
 	return 1
+
+# Soft keywords
+
+#: E271
+type  Number = int
+
+#: E273
+type	Number = int
+
+#: E275
+match(foo):
+    case(1):
+        pass

crates/ruff_linter/resources/test/fixtures/pycodestyle/W605_0.py

@@ -46,3 +46,15 @@ regex = '\\\_'
 
 #: W605:1:7
 u'foo\ bar'
+
+#: W605:1:13
+(
+    "foo \
+    bar \. baz"
+)
+
+#: W605:1:6
+"foo \. bar \t"
+
+#: W605:1:13
+"foo \t bar \."

crates/ruff_linter/resources/test/fixtures/refurb/FURB110.py

@@ -38,3 +38,12 @@ z = (
     else
     y
 )
+
+# FURB110
+z = (
+    x
+    if x
+    else y
+    if y > 0
+    else None
+)

crates/ruff_linter/src/rules/flake8_bugbear/mod.rs

@@ -13,6 +13,7 @@ mod tests {
     use crate::assert_messages;
     use crate::registry::Rule;
 
+    use crate::settings::types::PreviewMode;
     use crate::settings::LinterSettings;
     use crate::test::test_path;
 
@@ -62,6 +63,7 @@ mod tests {
     #[test_case(Rule::UselessContextlibSuppress, Path::new("B022.py"))]
     #[test_case(Rule::UselessExpression, Path::new("B018.ipynb"))]
     #[test_case(Rule::UselessExpression, Path::new("B018.py"))]
+    #[test_case(Rule::UselessExpression, Path::new("B018_attribute_docstring.py"))]
     #[test_case(Rule::LoopIteratorMutation, Path::new("B909.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
         let snapshot = format!("{}_{}", rule_code.noqa_code(), path.to_string_lossy());
@@ -73,6 +75,26 @@ mod tests {
         Ok(())
     }
 
+    #[test_case(Rule::UselessExpression, Path::new("B018.ipynb"))]
+    #[test_case(Rule::UselessExpression, Path::new("B018.py"))]
+    #[test_case(Rule::UselessExpression, Path::new("B018_attribute_docstring.py"))]
+    fn preview_rules(rule_code: Rule, path: &Path) -> Result<()> {
+        let snapshot = format!(
+            "preview__{}_{}",
+            rule_code.noqa_code(),
+            path.to_string_lossy()
+        );
+        let diagnostics = test_path(
+            Path::new("flake8_bugbear").join(path).as_path(),
+            &LinterSettings {
+                preview: PreviewMode::Enabled,
+                ..LinterSettings::for_rule(rule_code)
+            },
+        )?;
+        assert_messages!(snapshot, diagnostics);
+        Ok(())
+    }
+
     #[test]
     fn zip_without_explicit_strict() -> Result<()> {
         let snapshot = "B905.py";

crates/ruff_linter/src/rules/flake8_bugbear/rules/useless_expression.rs

@@ -16,6 +16,9 @@ use super::super::helpers::at_last_top_level_expression_in_cell;
 /// by mistake. Assign a useless expression to a variable, or remove it
 /// entirely.
 ///
+/// In [preview mode], this rule will also flag string literals and f-strings that
+/// are not used as a docstring or an attribute docstring.
+///
 /// ## Example
 /// ```python
 /// 1 + 1
@@ -45,6 +48,8 @@ use super::super::helpers::at_last_top_level_expression_in_cell;
 /// with errors.ExceptionRaisedContext():
 ///     _ = obj.attribute
 /// ```
+///
+/// [preview]: https://docs.astral.sh/ruff/preview/
 #[violation]
 pub struct UselessExpression {
     kind: Kind,
@@ -69,15 +74,16 @@ impl Violation for UselessExpression {
 /// B018
 pub(crate) fn useless_expression(checker: &mut Checker, value: &Expr) {
     // Ignore comparisons, as they're handled by `useless_comparison`.
-    if value.is_compare_expr() {
+    if matches!(value, Expr::Compare(_) | Expr::EllipsisLiteral(_)) {
         return;
     }
 
-    // Ignore strings, to avoid false positives with docstrings.
-    if matches!(
-        value,
-        Expr::FString(_) | Expr::StringLiteral(_) | Expr::EllipsisLiteral(_)
-    ) {
+    if checker.settings.preview.is_enabled() {
+        if checker.semantic().in_pep_257_docstring() || checker.semantic().in_attribute_docstring()
+        {
+            return;
+        }
+    } else if matches!(value, Expr::StringLiteral(_) | Expr::FString(_)) {
         return;
     }
 

crates/ruff_linter/src/rules/flake8_bugbear/snapshots/ruff_linter__rules__flake8_bugbear__tests__B018_B018.py.snap

@@ -3,8 +3,8 @@ source: crates/ruff_linter/src/rules/flake8_bugbear/mod.rs
 ---
 B018.py:11:5: B018 Found useless expression. Either assign it to a variable or remove it.
    |
- 9 |     "str"  # Str (no raise)
-10 |     f"{int}"  # JoinedStr (no raise)
+ 9 |     "str"  # StringLiteral
+10 |     f"{int}"  # FString
 11 |     1j  # Number (complex)
    |     ^^ B018
 12 |     1  # Number (int)
@@ -13,7 +13,7 @@ B018.py:11:5: B018 Found useless expression. Either assign it to a variable or r
 
 B018.py:12:5: B018 Found useless expression. Either assign it to a variable or remove it.
    |
-10 |     f"{int}"  # JoinedStr (no raise)
+10 |     f"{int}"  # FString
 11 |     1j  # Number (complex)
 12 |     1  # Number (int)
    |     ^ B018
@@ -117,8 +117,8 @@ B018.py:27:5: B018 Found useless expression. Either assign it to a variable or r
 
 B018.py:39:5: B018 Found useless expression. Either assign it to a variable or remove it.
    |
-37 |     "str"  # Str (no raise)
-38 |     f"{int}"  # JoinedStr (no raise)
+37 |     "str"  # StringLiteral
+38 |     f"{int}"  # FString
 39 |     1j  # Number (complex)
    |     ^^ B018
 40 |     1  # Number (int)
@@ -127,7 +127,7 @@ B018.py:39:5: B018 Found useless expression. Either assign it to a variable or r
 
 B018.py:40:5: B018 Found useless expression. Either assign it to a variable or remove it.
    |
-38 |     f"{int}"  # JoinedStr (no raise)
+38 |     f"{int}"  # FString
 39 |     1j  # Number (complex)
 40 |     1  # Number (int)
    |     ^ B018
@@ -254,5 +254,3 @@ B018.py:65:5: B018 Found useless expression. Either assign it to a variable or r
 65 |     "foo" + "bar"  # BinOp (raise)
    |     ^^^^^^^^^^^^^ B018
    |
-
-

crates/ruff_linter/src/rules/flake8_bugbear/snapshots/ruff_linter__rules__flake8_bugbear__tests__B018_B018_attribute_docstring.py.snap

@@ -0,0 +1,11 @@
+---
+source: crates/ruff_linter/src/rules/flake8_bugbear/mod.rs
+---
+B018_attribute_docstring.py:22:2: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+20 |     "d: not a docstring"
+21 | 
+22 | (e := 1)
+   |  ^^^^^^ B018
+23 | "e: not a docstring"
+   |

crates/ruff_linter/src/rules/flake8_bugbear/snapshots/ruff_linter__rules__flake8_bugbear__tests__preview__B018_B018.ipynb.snap

@@ -0,0 +1,32 @@
+---
+source: crates/ruff_linter/src/rules/flake8_bugbear/mod.rs
+---
+B018.ipynb:5:1: B018 Found useless expression. Either assign it to a variable or remove it.
+  |
+3 | x
+4 | # Only skip the last expression
+5 | x  # B018
+  | ^ B018
+6 | x
+7 | # Nested expressions isn't relevant
+  |
+
+B018.ipynb:9:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+ 7 | # Nested expressions isn't relevant
+ 8 | if True:
+ 9 |     x
+   |     ^ B018
+10 | # Semicolons shouldn't affect the output
+11 | x;
+   |
+
+B018.ipynb:13:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+11 | x;
+12 | # Semicolons with multiple expressions
+13 | x; x
+   | ^ B018
+14 | # Comments, newlines and whitespace
+15 | x  # comment
+   |

crates/ruff_linter/src/rules/flake8_bugbear/snapshots/ruff_linter__rules__flake8_bugbear__tests__preview__B018_B018.py.snap

@@ -0,0 +1,295 @@
+---
+source: crates/ruff_linter/src/rules/flake8_bugbear/mod.rs
+---
+B018.py:10:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+ 8 |     a = 2
+ 9 |     "str"  # StringLiteral
+10 |     f"{int}"  # FString
+   |     ^^^^^^^^ B018
+11 |     1j  # Number (complex)
+12 |     1  # Number (int)
+   |
+
+B018.py:11:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+ 9 |     "str"  # StringLiteral
+10 |     f"{int}"  # FString
+11 |     1j  # Number (complex)
+   |     ^^ B018
+12 |     1  # Number (int)
+13 |     1.0  # Number (float)
+   |
+
+B018.py:12:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+10 |     f"{int}"  # FString
+11 |     1j  # Number (complex)
+12 |     1  # Number (int)
+   |     ^ B018
+13 |     1.0  # Number (float)
+14 |     b"foo"  # Binary
+   |
+
+B018.py:13:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+11 |     1j  # Number (complex)
+12 |     1  # Number (int)
+13 |     1.0  # Number (float)
+   |     ^^^ B018
+14 |     b"foo"  # Binary
+15 |     True  # NameConstant (True)
+   |
+
+B018.py:14:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+12 |     1  # Number (int)
+13 |     1.0  # Number (float)
+14 |     b"foo"  # Binary
+   |     ^^^^^^ B018
+15 |     True  # NameConstant (True)
+16 |     False  # NameConstant (False)
+   |
+
+B018.py:15:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+13 |     1.0  # Number (float)
+14 |     b"foo"  # Binary
+15 |     True  # NameConstant (True)
+   |     ^^^^ B018
+16 |     False  # NameConstant (False)
+17 |     None  # NameConstant (None)
+   |
+
+B018.py:16:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+14 |     b"foo"  # Binary
+15 |     True  # NameConstant (True)
+16 |     False  # NameConstant (False)
+   |     ^^^^^ B018
+17 |     None  # NameConstant (None)
+18 |     [1, 2]  # list
+   |
+
+B018.py:17:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+15 |     True  # NameConstant (True)
+16 |     False  # NameConstant (False)
+17 |     None  # NameConstant (None)
+   |     ^^^^ B018
+18 |     [1, 2]  # list
+19 |     {1, 2}  # set
+   |
+
+B018.py:18:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+16 |     False  # NameConstant (False)
+17 |     None  # NameConstant (None)
+18 |     [1, 2]  # list
+   |     ^^^^^^ B018
+19 |     {1, 2}  # set
+20 |     {"foo": "bar"}  # dict
+   |
+
+B018.py:19:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+17 |     None  # NameConstant (None)
+18 |     [1, 2]  # list
+19 |     {1, 2}  # set
+   |     ^^^^^^ B018
+20 |     {"foo": "bar"}  # dict
+   |
+
+B018.py:20:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+18 |     [1, 2]  # list
+19 |     {1, 2}  # set
+20 |     {"foo": "bar"}  # dict
+   |     ^^^^^^^^^^^^^^ B018
+   |
+
+B018.py:24:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+23 | class Foo3:
+24 |     123
+   |     ^^^ B018
+25 |     a = 2
+26 |     "str"
+   |
+
+B018.py:27:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+25 |     a = 2
+26 |     "str"
+27 |     1
+   |     ^ B018
+   |
+
+B018.py:37:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+35 |     """my docstring"""
+36 |     a = 2
+37 |     "str"  # StringLiteral
+   |     ^^^^^ B018
+38 |     f"{int}"  # FString
+39 |     1j  # Number (complex)
+   |
+
+B018.py:38:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+36 |     a = 2
+37 |     "str"  # StringLiteral
+38 |     f"{int}"  # FString
+   |     ^^^^^^^^ B018
+39 |     1j  # Number (complex)
+40 |     1  # Number (int)
+   |
+
+B018.py:39:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+37 |     "str"  # StringLiteral
+38 |     f"{int}"  # FString
+39 |     1j  # Number (complex)
+   |     ^^ B018
+40 |     1  # Number (int)
+41 |     1.0  # Number (float)
+   |
+
+B018.py:40:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+38 |     f"{int}"  # FString
+39 |     1j  # Number (complex)
+40 |     1  # Number (int)
+   |     ^ B018
+41 |     1.0  # Number (float)
+42 |     b"foo"  # Binary
+   |
+
+B018.py:41:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+39 |     1j  # Number (complex)
+40 |     1  # Number (int)
+41 |     1.0  # Number (float)
+   |     ^^^ B018
+42 |     b"foo"  # Binary
+43 |     True  # NameConstant (True)
+   |
+
+B018.py:42:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+40 |     1  # Number (int)
+41 |     1.0  # Number (float)
+42 |     b"foo"  # Binary
+   |     ^^^^^^ B018
+43 |     True  # NameConstant (True)
+44 |     False  # NameConstant (False)
+   |
+
+B018.py:43:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+41 |     1.0  # Number (float)
+42 |     b"foo"  # Binary
+43 |     True  # NameConstant (True)
+   |     ^^^^ B018
+44 |     False  # NameConstant (False)
+45 |     None  # NameConstant (None)
+   |
+
+B018.py:44:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+42 |     b"foo"  # Binary
+43 |     True  # NameConstant (True)
+44 |     False  # NameConstant (False)
+   |     ^^^^^ B018
+45 |     None  # NameConstant (None)
+46 |     [1, 2]  # list
+   |
+
+B018.py:45:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+43 |     True  # NameConstant (True)
+44 |     False  # NameConstant (False)
+45 |     None  # NameConstant (None)
+   |     ^^^^ B018
+46 |     [1, 2]  # list
+47 |     {1, 2}  # set
+   |
+
+B018.py:46:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+44 |     False  # NameConstant (False)
+45 |     None  # NameConstant (None)
+46 |     [1, 2]  # list
+   |     ^^^^^^ B018
+47 |     {1, 2}  # set
+48 |     {"foo": "bar"}  # dict
+   |
+
+B018.py:47:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+45 |     None  # NameConstant (None)
+46 |     [1, 2]  # list
+47 |     {1, 2}  # set
+   |     ^^^^^^ B018
+48 |     {"foo": "bar"}  # dict
+   |
+
+B018.py:48:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+46 |     [1, 2]  # list
+47 |     {1, 2}  # set
+48 |     {"foo": "bar"}  # dict
+   |     ^^^^^^^^^^^^^^ B018
+   |
+
+B018.py:52:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+51 | def foo3():
+52 |     123
+   |     ^^^ B018
+53 |     a = 2
+54 |     "str"
+   |
+
+B018.py:54:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+52 |     123
+53 |     a = 2
+54 |     "str"
+   |     ^^^^^ B018
+55 |     3
+   |
+
+B018.py:55:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+53 |     a = 2
+54 |     "str"
+55 |     3
+   |     ^ B018
+   |
+
+B018.py:63:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+62 | def foo5():
+63 |     foo.bar  # Attribute (raise)
+   |     ^^^^^^^ B018
+64 |     object().__class__  # Attribute (raise)
+65 |     "foo" + "bar"  # BinOp (raise)
+   |
+
+B018.py:64:5: B018 Found useless attribute access. Either assign it to a variable or remove it.
+   |
+62 | def foo5():
+63 |     foo.bar  # Attribute (raise)
+64 |     object().__class__  # Attribute (raise)
+   |     ^^^^^^^^^^^^^^^^^^ B018
+65 |     "foo" + "bar"  # BinOp (raise)
+   |
+
+B018.py:65:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+63 |     foo.bar  # Attribute (raise)
+64 |     object().__class__  # Attribute (raise)
+65 |     "foo" + "bar"  # BinOp (raise)
+   |     ^^^^^^^^^^^^^ B018
+   |

crates/ruff_linter/src/rules/flake8_bugbear/snapshots/ruff_linter__rules__flake8_bugbear__tests__preview__B018_B018_attribute_docstring.py.snap

@@ -0,0 +1,165 @@
+---
+source: crates/ruff_linter/src/rules/flake8_bugbear/mod.rs
+---
+B018_attribute_docstring.py:10:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+ 8 | b = 1
+ 9 | "b: docstring" " continue"
+10 | "b: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^ B018
+11 | 
+12 | c: int = 1
+   |
+
+B018_attribute_docstring.py:20:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+18 | if True:
+19 |     d = 1
+20 |     "d: not a docstring"
+   |     ^^^^^^^^^^^^^^^^^^^^ B018
+21 | 
+22 | (e := 1)
+   |
+
+B018_attribute_docstring.py:22:2: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+20 |     "d: not a docstring"
+21 | 
+22 | (e := 1)
+   |  ^^^^^^ B018
+23 | "e: not a docstring"
+   |
+
+B018_attribute_docstring.py:23:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+22 | (e := 1)
+23 | "e: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^ B018
+24 | 
+25 | f = 0
+   |
+
+B018_attribute_docstring.py:27:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+25 | f = 0
+26 | f += 1
+27 | "f: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^ B018
+28 | 
+29 | g.h = 1
+   |
+
+B018_attribute_docstring.py:30:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+29 | g.h = 1
+30 | "g.h: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^^^ B018
+31 | 
+32 | (i) = 1
+   |
+
+B018_attribute_docstring.py:42:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+41 | l = m = 1
+42 | "l m: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^^^ B018
+43 | 
+44 | n.a = n.b = n.c = 1
+   |
+
+B018_attribute_docstring.py:45:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+44 | n.a = n.b = n.c = 1
+45 | "n.*: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^^^ B018
+46 | 
+47 | (o, p) = (1, 2)
+   |
+
+B018_attribute_docstring.py:48:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+47 | (o, p) = (1, 2)
+48 | "o p: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^^^ B018
+49 | 
+50 | [q, r] = [1, 2]
+   |
+
+B018_attribute_docstring.py:51:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+50 | [q, r] = [1, 2]
+51 | "q r: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^^^ B018
+52 | 
+53 | *s = 1
+   |
+
+B018_attribute_docstring.py:54:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+53 | *s = 1
+54 | "s: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^ B018
+   |
+
+B018_attribute_docstring.py:63:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+61 |     b: int
+62 |     "Foo.b: docstring"
+63 |     "Foo.b: not a docstring"
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^ B018
+64 | 
+65 |     c: int = 1
+   |
+
+B018_attribute_docstring.py:71:9: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+69 |         # This is actually a docstring but we currently don't detect it.
+70 |         self.x = 1
+71 |         "self.x: not a docstring"
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^ B018
+72 | 
+73 |         t = 2
+   |
+
+B018_attribute_docstring.py:74:9: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+73 |         t = 2
+74 |         "t: not a docstring"
+   |         ^^^^^^^^^^^^^^^^^^^^ B018
+75 | 
+76 |     def random(self):
+   |
+
+B018_attribute_docstring.py:78:9: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+76 |     def random(self):
+77 |         self.y = 2
+78 |         "self.y: not a docstring"
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^ B018
+79 | 
+80 |         u = 2
+   |
+
+B018_attribute_docstring.py:81:9: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+80 |         u = 2
+81 |         "u: not a docstring"
+   |         ^^^^^^^^^^^^^^^^^^^^ B018
+82 | 
+83 |     def add(self, y: int):
+   |
+
+B018_attribute_docstring.py:89:5: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+87 | def function():
+88 |     v = 2
+89 |     "v: not a docstring"
+   |     ^^^^^^^^^^^^^^^^^^^^ B018
+   |
+
+B018_attribute_docstring.py:93:1: B018 Found useless expression. Either assign it to a variable or remove it.
+   |
+92 | function.a = 1
+93 | "function.a: not a docstring"
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ B018
+   |

crates/ruff_linter/src/rules/pycodestyle/rules/invalid_escape_sequence.rs

@@ -181,6 +181,7 @@ fn check(
 
         // If we're at the end of line, skip.
         if matches!(next_char, '\n' | '\r') {
+            contains_valid_escape_sequence = true;
             continue;
         }
 

crates/ruff_linter/src/rules/pycodestyle/rules/logical_lines/missing_whitespace_after_keyword.rs

@@ -52,7 +52,7 @@ pub(crate) fn missing_whitespace_after_keyword(
         let tok0_kind = tok0.kind();
         let tok1_kind = tok1.kind();
 
-        if tok0_kind.is_non_soft_keyword()
+        if tok0_kind.is_keyword()
             && !(tok0_kind.is_singleton()
                 || matches!(tok0_kind, TokenKind::Async | TokenKind::Await)
                 || tok0_kind == TokenKind::Except && tok1_kind == TokenKind::Star

crates/ruff_linter/src/rules/pycodestyle/rules/logical_lines/mod.rs

@@ -445,7 +445,7 @@ impl LogicalLinesBuilder {
 
         if matches!(kind, TokenKind::Comma | TokenKind::Semi | TokenKind::Colon) {
             line.flags.insert(TokenFlags::PUNCTUATION);
-        } else if kind.is_non_soft_keyword() {
+        } else if kind.is_keyword() {
             line.flags.insert(TokenFlags::KEYWORD);
         }
 

crates/ruff_linter/src/rules/pycodestyle/rules/logical_lines/whitespace_around_keywords.rs

@@ -127,8 +127,8 @@ pub(crate) fn whitespace_around_keywords(line: &LogicalLine, context: &mut Logic
     let mut after_keyword = false;
 
     for token in line.tokens() {
-        let is_non_soft_keyword = token.kind().is_non_soft_keyword();
-        if is_non_soft_keyword {
+        let is_keyword = token.kind().is_keyword();
+        if is_keyword {
             if !after_keyword {
                 match line.leading_whitespace(token) {
                     (Whitespace::Tab, offset) => {
@@ -184,6 +184,6 @@ pub(crate) fn whitespace_around_keywords(line: &LogicalLine, context: &mut Logic
             }
         }
 
-        after_keyword = is_non_soft_keyword;
+        after_keyword = is_keyword;
     }
 }

crates/ruff_linter/src/rules/pycodestyle/rules/tab_indentation.rs

@@ -11,18 +11,6 @@ use ruff_text_size::{TextRange, TextSize};
 /// According to [PEP 8], spaces are preferred over tabs (unless used to remain
 /// consistent with code that is already indented with tabs).
 ///
-/// ## Example
-/// ```python
-/// if True:
-/// 	a = 1
-/// ```
-///
-/// Use instead:
-/// ```python
-/// if True:
-///     a = 1
-/// ```
-///
 /// ## Formatter compatibility
 /// We recommend against using this rule alongside the [formatter]. The
 /// formatter enforces consistent indentation, making the rule redundant.

crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__E271_E27.py.snap

@@ -190,4 +190,22 @@ E27.py:35:14: E271 [*] Multiple spaces after keyword
 37 37 | from w import(e, f)
 38 38 | #: E275
 
+E27.py:70:5: E271 [*] Multiple spaces after keyword
+   |
+69 | #: E271
+70 | type  Number = int
+   |     ^^ E271
+71 | 
+72 | #: E273
+   |
+   = help: Replace with single space
 
+ℹ Safe fix
+67 67 | # Soft keywords
+68 68 | 
+69 69 | #: E271
+70    |-type  Number = int
+   70 |+type Number = int
+71 71 | 
+72 72 | #: E273
+73 73 | type	Number = int

crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__E273_E27.py.snap

@@ -106,4 +106,22 @@ E27.py:30:10: E273 [*] Tab after keyword
 32 32 | from u import (a, b)
 33 33 | from v import c, d
 
+E27.py:73:5: E273 [*] Tab after keyword
+   |
+72 | #: E273
+73 | type    Number = int
+   |     ^^^^ E273
+74 | 
+75 | #: E275
+   |
+   = help: Replace with single space
 
+ℹ Safe fix
+70 70 | type  Number = int
+71 71 | 
+72 72 | #: E273
+73    |-type	Number = int
+   73 |+type Number = int
+74 74 | 
+75 75 | #: E275
+76 76 | match(foo):

crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__E275_E27.py.snap

@@ -106,4 +106,39 @@ E27.py:54:5: E275 [*] Missing whitespace after keyword
 56 56 | def f():
 57 57 |     print((yield))
 
+E27.py:76:1: E275 [*] Missing whitespace after keyword
+   |
+75 | #: E275
+76 | match(foo):
+   | ^^^^^ E275
+77 |     case(1):
+78 |         pass
+   |
+   = help: Added missing whitespace after keyword
 
+ℹ Safe fix
+73 73 | type	Number = int
+74 74 | 
+75 75 | #: E275
+76    |-match(foo):
+   76 |+match (foo):
+77 77 |     case(1):
+78 78 |         pass
+
+E27.py:77:5: E275 [*] Missing whitespace after keyword
+   |
+75 | #: E275
+76 | match(foo):
+77 |     case(1):
+   |     ^^^^ E275
+78 |         pass
+   |
+   = help: Added missing whitespace after keyword
+
+ℹ Safe fix
+74 74 | 
+75 75 | #: E275
+76 76 | match(foo):
+77    |-    case(1):
+   77 |+    case (1):
+78 78 |         pass

crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__W605_W605_0.py.snap

@@ -145,6 +145,8 @@ W605_0.py:48:6: W605 [*] Invalid escape sequence: `\ `
 47 | #: W605:1:7
 48 | u'foo\ bar'
    |      ^^ W605
+49 | 
+50 | #: W605:1:13
    |
    = help: Use a raw string literal
 
@@ -154,5 +156,61 @@ W605_0.py:48:6: W605 [*] Invalid escape sequence: `\ `
 47 47 | #: W605:1:7
 48    |-u'foo\ bar'
    48 |+r'foo\ bar'
+49 49 | 
+50 50 | #: W605:1:13
+51 51 | (
 
+W605_0.py:53:9: W605 [*] Invalid escape sequence: `\.`
+   |
+51 | (
+52 |     "foo \
+53 |     bar \. baz"
+   |         ^^ W605
+54 | )
+   |
+   = help: Add backslash to escape sequence
 
+ℹ Safe fix
+50 50 | #: W605:1:13
+51 51 | (
+52 52 |     "foo \
+53    |-    bar \. baz"
+   53 |+    bar \\. baz"
+54 54 | )
+55 55 | 
+56 56 | #: W605:1:6
+
+W605_0.py:57:6: W605 [*] Invalid escape sequence: `\.`
+   |
+56 | #: W605:1:6
+57 | "foo \. bar \t"
+   |      ^^ W605
+58 | 
+59 | #: W605:1:13
+   |
+   = help: Add backslash to escape sequence
+
+ℹ Safe fix
+54 54 | )
+55 55 | 
+56 56 | #: W605:1:6
+57    |-"foo \. bar \t"
+   57 |+"foo \\. bar \t"
+58 58 | 
+59 59 | #: W605:1:13
+60 60 | "foo \t bar \."
+
+W605_0.py:60:13: W605 [*] Invalid escape sequence: `\.`
+   |
+59 | #: W605:1:13
+60 | "foo \t bar \."
+   |             ^^ W605
+   |
+   = help: Add backslash to escape sequence
+
+ℹ Safe fix
+57 57 | "foo \. bar \t"
+58 58 | 
+59 59 | #: W605:1:13
+60    |-"foo \t bar \."
+   60 |+"foo \t bar \\."

crates/ruff_linter/src/rules/refurb/rules/if_exp_instead_of_or_operator.rs

@@ -1,9 +1,14 @@
+use std::borrow::Cow;
+
 use ruff_diagnostics::{Applicability, Diagnostic, Edit, Fix, FixAvailability, Violation};
 use ruff_macros::{derive_message_formats, violation};
 use ruff_python_ast as ast;
 use ruff_python_ast::comparable::ComparableExpr;
 use ruff_python_ast::helpers::contains_effect;
 use ruff_python_ast::parenthesize::parenthesized_range;
+use ruff_python_ast::Expr;
+use ruff_python_index::Indexer;
+use ruff_source_file::Locator;
 use ruff_text_size::Ranged;
 
 use crate::checkers::ast::Checker;
@@ -64,29 +69,13 @@ pub(crate) fn if_exp_instead_of_or_operator(checker: &mut Checker, if_expr: &ast
 
     let mut diagnostic = Diagnostic::new(IfExpInsteadOfOrOperator, *range);
 
-    // Grab the range of the `test` and `orelse` expressions.
-    let left = parenthesized_range(
-        test.into(),
-        if_expr.into(),
-        checker.indexer().comment_ranges(),
-        checker.locator().contents(),
-    )
-    .unwrap_or(test.range());
-    let right = parenthesized_range(
-        orelse.into(),
-        if_expr.into(),
-        checker.indexer().comment_ranges(),
-        checker.locator().contents(),
-    )
-    .unwrap_or(orelse.range());
-
     // Replace with `{test} or {orelse}`.
     diagnostic.set_fix(Fix::applicable_edit(
         Edit::range_replacement(
             format!(
                 "{} or {}",
-                checker.locator().slice(left),
-                checker.locator().slice(right),
+                parenthesize_test(test, if_expr, checker.indexer(), checker.locator()),
+                parenthesize_test(orelse, if_expr, checker.indexer(), checker.locator()),
             ),
             if_expr.range(),
         ),
@@ -99,3 +88,30 @@ pub(crate) fn if_exp_instead_of_or_operator(checker: &mut Checker, if_expr: &ast
 
     checker.diagnostics.push(diagnostic);
 }
+
+/// Parenthesize an expression for use in an `or` operator (e.g., parenthesize `x` in `x or y`),
+/// if it's required to maintain the correct order of operations.
+///
+/// If the expression is already parenthesized, it will be returned as-is regardless of whether
+/// the parentheses are required.
+///
+/// See: <https://docs.python.org/3/reference/expressions.html#operator-precedence>
+fn parenthesize_test<'a>(
+    expr: &Expr,
+    if_expr: &ast::ExprIf,
+    indexer: &Indexer,
+    locator: &Locator<'a>,
+) -> Cow<'a, str> {
+    if let Some(range) = parenthesized_range(
+        expr.into(),
+        if_expr.into(),
+        indexer.comment_ranges(),
+        locator.contents(),
+    ) {
+        Cow::Borrowed(locator.slice(range))
+    } else if matches!(expr, Expr::If(_) | Expr::Lambda(_) | Expr::Named(_)) {
+        Cow::Owned(format!("({})", locator.slice(expr.range())))
+    } else {
+        Cow::Borrowed(locator.slice(expr.range()))
+    }
+}

crates/ruff_linter/src/rules/refurb/snapshots/ruff_linter__rules__refurb__tests__FURB110_FURB110.py.snap

@@ -177,3 +177,33 @@ FURB110.py:34:5: FURB110 [*] Replace ternary `if` expression with `or` operator
 39    |-    y
    34 |+    x or y
 40 35 | )
+41 36 | 
+42 37 | # FURB110
+
+FURB110.py:44:5: FURB110 [*] Replace ternary `if` expression with `or` operator
+   |
+42 |   # FURB110
+43 |   z = (
+44 |       x
+   |  _____^
+45 | |     if x
+46 | |     else y
+47 | |     if y > 0
+48 | |     else None
+   | |_____________^ FURB110
+49 |   )
+   |
+   = help: Replace with `or` operator
+
+ℹ Safe fix
+41 41 | 
+42 42 | # FURB110
+43 43 | z = (
+44    |-    x
+45    |-    if x
+46    |-    else y
+   44 |+    x or (y
+47 45 |     if y > 0
+48    |-    else None
+   46 |+    else None)
+49 47 | )

python/ruff-ecosystem/ruff_ecosystem/check.py

@@ -145,7 +145,20 @@ def markdown_check_result(result: Result) -> str:
 
         # Limit the number of items displayed per project to between 10 and 50
         # based on the proportion of total changes present in this project
-        max_display_per_project = max(10, int((project_changes / total_changes) * 50))
+        max_display_per_project = max(
+            10,
+            int(
+                (
+                    # TODO(zanieb): We take the `max` here to avoid division by zero errors where
+                    # `total_changes` is zero but `total_affected_rules` is non-zero so we did not
+                    # skip display. This shouldn't really happen and indicates a problem in the
+                    # calculation of these values. Instead of skipping entirely when `total_changes`
+                    # is zero, we'll attempt to report the results to help diagnose the problem.
+                    project_changes / max(total_changes, 1)
+                )
+                * 50
+            ),
+        )
 
         # Limit the number of items displayed per rule to between 5 and the max for
         # the project based on the number of rules affected (less rules, more per rule)

python/ruff-ecosystem/ruff_ecosystem/defaults.py

@@ -30,7 +30,6 @@ DEFAULT_TARGETS = [
         repo=Repository(owner="bokeh", name="bokeh", ref="branch-3.3"),
         check_options=CheckOptions(select="ALL"),
     ),
-    Project(repo=Repository(owner="commaai", name="openpilot", ref="master")),
     Project(
         repo=Repository(owner="demisto", name="content", ref="master"),
         format_options=FormatOptions(
@@ -117,4 +116,11 @@ DEFAULT_TARGETS = [
             ],
         },
     ),
+    Project(repo=Repository(owner="agronholm", name="anyio", ref="master")),
+    Project(repo=Repository(owner="python-trio", name="trio", ref="master")),
+    Project(repo=Repository(owner="wntrblm", name="nox", ref="main")),
+    Project(repo=Repository(owner="pytest-dev", name="pytest", ref="main")),
+    Project(repo=Repository(owner="encode", name="httpx", ref="master")),
+    Project(repo=Repository(owner="mesonbuild", name="meson-python", ref="main")),
+    Project(repo=Repository(owner="pdm-project", name="pdm", ref="main")),
 ]

scripts/check_docs_formatted.py

@@ -74,7 +74,6 @@ KNOWN_FORMATTING_VIOLATIONS = [
     "redundant-backslash",
     "shebang-leading-whitespace",
     "surrounding-whitespace",
-    "tab-indentation",
     "too-few-spaces-before-inline-comment",
     "too-many-blank-lines",
     "too-many-boolean-expressions",

scripts/check_ecosystem.py

@@ -124,7 +124,6 @@ REPOSITORIES: list[Repository] = [
     Repository("aws", "aws-sam-cli", "develop"),
     Repository("bloomberg", "pytest-memray", "main"),
     Repository("bokeh", "bokeh", "branch-3.3", select="ALL"),
-    Repository("commaai", "openpilot", "master"),
     Repository("demisto", "content", "master"),
     Repository("docker", "docker-py", "main"),
     Repository("freedomofpress", "securedrop", "develop"),