Remove functor from autofix title (#4245)

crates/ruff/src/rules/flake8_bugbear/rules/unused_loop_control_variable.rs

@@ -65,18 +65,12 @@ impl Violation for UnusedLoopControlVariable {
         }
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        let UnusedLoopControlVariable {
+        let UnusedLoopControlVariable { rename, name, .. } = self;
-            certainty, rename, ..
+
-        } = self;
+        rename
-        if certainty.to_bool() && rename.is_some() {
+            .as_ref()
-            Some(|UnusedLoopControlVariable { name, rename, .. }| {
+            .map(|rename| format!("Rename unused `{name}` to `{rename}`"))
-                let rename = rename.as_ref().unwrap();
-                format!("Rename unused `{name}` to `{rename}`")
-            })
-        } else {
-            None
-        }
     }
 }
 

crates/ruff/src/rules/flake8_bugbear/snapshots/ruff__rules__flake8_bugbear__tests__B007_B007.py.snap

@@ -65,6 +65,7 @@ B007.py:34:10: B007 Loop control variable `bar` may not be used within loop body
 36 |     if foo:
 37 |         print(FMT.format(**locals()))
    |
+   = help: Rename unused `bar` to `_bar`
 
 B007.py:38:10: B007 Loop control variable `bar` may not be used within loop body
    |
@@ -75,6 +76,7 @@ B007.py:38:10: B007 Loop control variable `bar` may not be used within loop body
 41 |     if foo:
 42 |         print(FMT.format(**globals()))
    |
+   = help: Rename unused `bar` to `_bar`
 
 B007.py:42:10: B007 Loop control variable `bar` may not be used within loop body
    |
@@ -85,6 +87,7 @@ B007.py:42:10: B007 Loop control variable `bar` may not be used within loop body
 45 |     if foo:
 46 |         print(FMT.format(**vars()))
    |
+   = help: Rename unused `bar` to `_bar`
 
 B007.py:46:10: B007 Loop control variable `bar` may not be used within loop body
    |
@@ -94,6 +97,7 @@ B007.py:46:10: B007 Loop control variable `bar` may not be used within loop body
    |          ^^^ B007
 49 |     print(FMT.format(foo=foo, bar=eval("bar")))
    |
+   = help: Rename unused `bar` to `_bar`
 
 B007.py:52:14: B007 [*] Loop control variable `bar` not used within loop body
    |

crates/ruff/src/rules/flake8_comprehensions/rules/unnecessary_comprehension_any_all.rs

@@ -50,8 +50,8 @@ impl Violation for UnnecessaryComprehensionAnyAll {
         format!("Unnecessary list comprehension.")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|_| "Remove unnecessary list comprehension".to_string())
+        Some("Remove unnecessary list comprehension".to_string())
     }
 }
 

crates/ruff/src/rules/flake8_comprehensions/rules/unnecessary_map.rs

@@ -56,13 +56,12 @@ impl Violation for UnnecessaryMap {
         }
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|UnnecessaryMap { obj_type }| {
+        let UnnecessaryMap { obj_type } = self;
-            if obj_type == "generator" {
+        Some(if obj_type == "generator" {
-                format!("Replace `map` using a generator expression")
+            format!("Replace `map` using a generator expression")
-            } else {
+        } else {
-                format!("Replace `map` using a `{obj_type}` comprehension")
+            format!("Replace `map` using a `{obj_type}` comprehension")
-            }
         })
     }
 }

crates/ruff/src/rules/flake8_errmsg/rules.rs

@@ -47,9 +47,7 @@ use crate::registry::{AsRule, Rule};
 /// RuntimeError: 'Some value' is incorrect
 /// ```
 #[violation]
-pub struct RawStringInException {
+pub struct RawStringInException;
-    fixable: bool,
-}
 
 impl Violation for RawStringInException {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
@@ -59,9 +57,8 @@ impl Violation for RawStringInException {
         format!("Exception must not use a string literal, assign to variable first")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        Some("Assign to variable; remove string literal".to_string())
-            .then_some(|_| format!("Assign to variable; remove string literal"))
     }
 }
 
@@ -104,9 +101,7 @@ impl Violation for RawStringInException {
 /// RuntimeError: 'Some value' is incorrect
 /// ```
 #[violation]
-pub struct FStringInException {
+pub struct FStringInException;
-    fixable: bool,
-}
 
 impl Violation for FStringInException {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
@@ -116,9 +111,8 @@ impl Violation for FStringInException {
         format!("Exception must not use an f-string literal, assign to variable first")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        Some("Assign to variable; remove f-string literal".to_string())
-            .then_some(|_| format!("Assign to variable; remove f-string literal"))
     }
 }
 
@@ -163,9 +157,7 @@ impl Violation for FStringInException {
 /// RuntimeError: 'Some value' is incorrect
 /// ```
 #[violation]
-pub struct DotFormatInException {
+pub struct DotFormatInException;
-    fixable: bool,
-}
 
 impl Violation for DotFormatInException {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
@@ -175,9 +167,8 @@ impl Violation for DotFormatInException {
         format!("Exception must not use a `.format()` string directly, assign to variable first")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        Some("Assign to variable; remove `.format()` string".to_string())
-            .then_some(|_| format!("Assign to variable; remove `.format()` string"))
     }
 }
 
@@ -241,12 +232,8 @@ pub fn string_in_exception(checker: &mut Checker, stmt: &Stmt, exc: &Expr) {
                                         None
                                     }
                                 });
-                            let mut diagnostic = Diagnostic::new(
+                            let mut diagnostic =
-                                RawStringInException {
+                                Diagnostic::new(RawStringInException, first.range());
-                                    fixable: indentation.is_some(),
-                                },
-                                first.range(),
-                            );
                             if let Some(indentation) = indentation {
                                 if checker.patch(diagnostic.kind.rule()) {
                                     diagnostic.set_fix(generate_fix(
@@ -273,12 +260,7 @@ pub fn string_in_exception(checker: &mut Checker, stmt: &Stmt, exc: &Expr) {
                                 }
                             },
                         );
-                        let mut diagnostic = Diagnostic::new(
+                        let mut diagnostic = Diagnostic::new(FStringInException, first.range());
-                            FStringInException {
-                                fixable: indentation.is_some(),
-                            },
-                            first.range(),
-                        );
                         if let Some(indentation) = indentation {
                             if checker.patch(diagnostic.kind.rule()) {
                                 diagnostic.set_fix(generate_fix(
@@ -305,12 +287,8 @@ pub fn string_in_exception(checker: &mut Checker, stmt: &Stmt, exc: &Expr) {
                                             None
                                         }
                                     });
-                                let mut diagnostic = Diagnostic::new(
+                                let mut diagnostic =
-                                    DotFormatInException {
+                                    Diagnostic::new(DotFormatInException, first.range());
-                                        fixable: indentation.is_some(),
-                                    },
-                                    first.range(),
-                                );
                                 if let Some(indentation) = indentation {
                                     if checker.patch(diagnostic.kind.rule()) {
                                         diagnostic.set_fix(generate_fix(

crates/ruff/src/rules/flake8_errmsg/snapshots/ruff__rules__flake8_errmsg__tests__custom.snap

@@ -66,6 +66,7 @@ EM.py:28:24: EM101 Exception must not use a string literal, assign to variable f
 30 |     raise RuntimeError("This is an example exception")
    |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ EM101
    |
+   = help: Assign to variable; remove string literal
 
 EM.py:35:24: EM101 [*] Exception must not use a string literal, assign to variable first
    |
@@ -93,6 +94,7 @@ EM.py:42:28: EM101 Exception must not use a string literal, assign to variable f
 43 |         raise RuntimeError("This is an example exception")
    |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ EM101
    |
+   = help: Assign to variable; remove string literal
 
 EM.py:47:28: EM101 [*] Exception must not use a string literal, assign to variable first
    |
@@ -164,6 +166,7 @@ EM.py:55:28: EM101 Exception must not use a string literal, assign to variable f
    |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ EM101
 57 | if foo: x = 1; raise RuntimeError("This is an example exception")
    |
+   = help: Assign to variable; remove string literal
 
 EM.py:56:35: EM101 Exception must not use a string literal, assign to variable first
    |
@@ -172,5 +175,6 @@ EM.py:56:35: EM101 Exception must not use a string literal, assign to variable f
 58 | if foo: x = 1; raise RuntimeError("This is an example exception")
    |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ EM101
    |
+   = help: Assign to variable; remove string literal
 
 

crates/ruff/src/rules/flake8_errmsg/snapshots/ruff__rules__flake8_errmsg__tests__defaults.snap

@@ -85,6 +85,7 @@ EM.py:28:24: EM101 Exception must not use a string literal, assign to variable f
 30 |     raise RuntimeError("This is an example exception")
    |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ EM101
    |
+   = help: Assign to variable; remove string literal
 
 EM.py:35:24: EM101 [*] Exception must not use a string literal, assign to variable first
    |
@@ -112,6 +113,7 @@ EM.py:42:28: EM101 Exception must not use a string literal, assign to variable f
 43 |         raise RuntimeError("This is an example exception")
    |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ EM101
    |
+   = help: Assign to variable; remove string literal
 
 EM.py:47:28: EM101 [*] Exception must not use a string literal, assign to variable first
    |
@@ -183,6 +185,7 @@ EM.py:55:28: EM101 Exception must not use a string literal, assign to variable f
    |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ EM101
 57 | if foo: x = 1; raise RuntimeError("This is an example exception")
    |
+   = help: Assign to variable; remove string literal
 
 EM.py:56:35: EM101 Exception must not use a string literal, assign to variable first
    |
@@ -191,5 +194,6 @@ EM.py:56:35: EM101 Exception must not use a string literal, assign to variable f
 58 | if foo: x = 1; raise RuntimeError("This is an example exception")
    |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ EM101
    |
+   = help: Assign to variable; remove string literal
 
 

crates/ruff/src/rules/flake8_pytest_style/rules/assertion.rs

@@ -51,9 +51,7 @@ use super::unittest_assert::UnittestAssert;
 ///     assert not something_else
 /// ```
 #[violation]
-pub struct PytestCompositeAssertion {
+pub struct PytestCompositeAssertion;
-    fixable: bool,
-}
 
 impl Violation for PytestCompositeAssertion {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
@@ -63,9 +61,8 @@ impl Violation for PytestCompositeAssertion {
         format!("Assertion should be broken down into multiple parts")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        Some("Break down assertion into multiple parts".to_string())
-            .then_some(|_| format!("Break down assertion into multiple parts"))
     }
 }
 
@@ -97,7 +94,6 @@ impl Violation for PytestAssertAlwaysFalse {
 #[violation]
 pub struct PytestUnittestAssertion {
     assertion: String,
-    fixable: bool,
 }
 
 impl Violation for PytestUnittestAssertion {
@@ -105,15 +101,13 @@ impl Violation for PytestUnittestAssertion {
 
     #[derive_message_formats]
     fn message(&self) -> String {
-        let PytestUnittestAssertion { assertion, .. } = self;
+        let PytestUnittestAssertion { assertion } = self;
         format!("Use a regular `assert` instead of unittest-style `{assertion}`")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let PytestUnittestAssertion { assertion } = self;
-            .then_some(|PytestUnittestAssertion { assertion, .. }| {
+        Some(format!("Replace `{assertion}(...)` with `assert ...`"))
-                format!("Replace `{assertion}(...)` with `assert ...`")
-            })
     }
 }
 
@@ -198,7 +192,6 @@ pub fn unittest_assertion(
                 let mut diagnostic = Diagnostic::new(
                     PytestUnittestAssertion {
                         assertion: unittest_assert.to_string(),
-                        fixable,
                     },
                     func.range(),
                 );
@@ -426,7 +419,7 @@ pub fn composite_condition(checker: &mut Checker, stmt: &Stmt, test: &Expr, msg:
         let fixable = matches!(composite, CompositionKind::Simple)
             && msg.is_none()
             && !has_comments_in(stmt.range(), checker.locator);
-        let mut diagnostic = Diagnostic::new(PytestCompositeAssertion { fixable }, stmt.range());
+        let mut diagnostic = Diagnostic::new(PytestCompositeAssertion, stmt.range());
         if fixable && checker.patch(diagnostic.kind.rule()) {
             #[allow(deprecated)]
             diagnostic.try_set_fix_from_edit(|| {

crates/ruff/src/rules/flake8_pytest_style/rules/parametrize.rs

@@ -26,11 +26,9 @@ impl Violation for PytestParametrizeNamesWrongType {
         format!("Wrong name(s) type in `@pytest.mark.parametrize`, expected `{expected}`")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|violation| {
+        let PytestParametrizeNamesWrongType { expected } = self;
-            let PytestParametrizeNamesWrongType { expected } = violation;
+        Some(format!("Use a `{expected}` for parameter names"))
-            format!("Use a `{expected}` for parameter names")
-        })
     }
 }
 

crates/ruff/src/rules/flake8_pytest_style/snapshots/ruff__rules__flake8_pytest_style__tests__PT009.snap

@@ -159,6 +159,7 @@ PT009.py:21:13: PT009 Use a regular `assert` instead of unittest-style `assertIs
 24 |             if expect_condition
 25 |             else self.assertIsNone(value)  # Error, unfixable
    |
+   = help: Replace `assertIsNotNone(...)` with `assert ...`
 
 PT009.py:23:18: PT009 Use a regular `assert` instead of unittest-style `assertIsNone`
    |
@@ -169,6 +170,7 @@ PT009.py:23:18: PT009 Use a regular `assert` instead of unittest-style `assertIs
 26 |         )
 27 |         return self.assertEqual(True,  False)  # Error, unfixable
    |
+   = help: Replace `assertIsNone(...)` with `assert ...`
 
 PT009.py:25:16: PT009 Use a regular `assert` instead of unittest-style `assertEqual`
    |
@@ -179,6 +181,7 @@ PT009.py:25:16: PT009 Use a regular `assert` instead of unittest-style `assertEq
 28 | 
 29 |     def test_assert_false(self):
    |
+   = help: Replace `assertEqual(...)` with `assert ...`
 
 PT009.py:28:9: PT009 [*] Use a regular `assert` instead of unittest-style `assertFalse`
    |

crates/ruff/src/rules/flake8_pytest_style/snapshots/ruff__rules__flake8_pytest_style__tests__PT018.snap

@@ -229,6 +229,7 @@ PT018.py:30:5: PT018 Assertion should be broken down into multiple parts
 32 |     assert not (something or something_else and something_third), "with message"
 33 |     # detected, but no autofix for mixed conditions (e.g. `a or b and c`)
    |
+   = help: Break down assertion into multiple parts
 
 PT018.py:31:5: PT018 Assertion should be broken down into multiple parts
    |
@@ -239,6 +240,7 @@ PT018.py:31:5: PT018 Assertion should be broken down into multiple parts
 34 |     # detected, but no autofix for mixed conditions (e.g. `a or b and c`)
 35 |     assert not (something or something_else and something_third)
    |
+   = help: Break down assertion into multiple parts
 
 PT018.py:33:5: PT018 Assertion should be broken down into multiple parts
    |
@@ -249,6 +251,7 @@ PT018.py:33:5: PT018 Assertion should be broken down into multiple parts
 36 |     # detected, but no autofix for parenthesized conditions
 37 |     assert (
    |
+   = help: Break down assertion into multiple parts
 
 PT018.py:35:5: PT018 Assertion should be broken down into multiple parts
    |

crates/ruff/src/rules/flake8_simplify/rules/ast_bool_op.rs

@@ -47,8 +47,7 @@ use crate::registry::AsRule;
 /// - [Python: "isinstance"](https://docs.python.org/3/library/functions.html#isinstance)
 #[violation]
 pub struct DuplicateIsinstanceCall {
-    pub name: Option<String>,
+    name: Option<String>,
-    fixable: bool,
 }
 
 impl Violation for DuplicateIsinstanceCall {
@@ -56,7 +55,7 @@ impl Violation for DuplicateIsinstanceCall {
 
     #[derive_message_formats]
     fn message(&self) -> String {
-        let DuplicateIsinstanceCall { name, .. } = self;
+        let DuplicateIsinstanceCall { name } = self;
         if let Some(name) = name {
             format!("Multiple `isinstance` calls for `{name}`, merge into a single call")
         } else {
@@ -64,15 +63,14 @@ impl Violation for DuplicateIsinstanceCall {
         }
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let DuplicateIsinstanceCall { name } = self;
-            .then_some(|DuplicateIsinstanceCall { name, .. }| {
+
-                if let Some(name) = name {
+        Some(if let Some(name) = name {
-                    format!("Merge `isinstance` calls for `{name}`")
+            format!("Merge `isinstance` calls for `{name}`")
-                } else {
+        } else {
-                    format!("Merge `isinstance` calls")
+            "Merge `isinstance` calls".to_string()
-                }
+        })
-            })
     }
 }
 
@@ -305,7 +303,6 @@ pub fn duplicate_isinstance_call(checker: &mut Checker, expr: &Expr) {
                     } else {
                         None
                     },
-                    fixable,
                 },
                 expr.range(),
             );

crates/ruff/src/rules/flake8_simplify/rules/ast_expr.rs

@@ -22,11 +22,9 @@ impl Violation for UncapitalizedEnvironmentVariables {
         format!("Use capitalized environment variable `{expected}` instead of `{original}`")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|violation| {
+        let UncapitalizedEnvironmentVariables { expected, original } = self;
-            let UncapitalizedEnvironmentVariables { expected, original } = violation;
+        Some(format!("Replace `{original}` with `{expected}`"))
-            format!("Replace `{original}` with `{expected}`")
-        })
     }
 }
 

crates/ruff/src/rules/flake8_simplify/rules/ast_if.rs

@@ -37,9 +37,7 @@ fn compare_body(body1: &[Stmt], body2: &[Stmt]) -> bool {
 }
 
 #[violation]
-pub struct CollapsibleIf {
+pub struct CollapsibleIf;
-    fixable: bool,
-}
 
 impl Violation for CollapsibleIf {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
@@ -49,16 +47,14 @@ impl Violation for CollapsibleIf {
         format!("Use a single `if` statement instead of nested `if` statements")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        Some("Combine `if` statements using `and`".to_string())
-            .then_some(|_| format!("Combine `if` statements using `and`"))
     }
 }
 
 #[violation]
 pub struct NeedlessBool {
     condition: String,
-    fixable: bool,
 }
 
 impl Violation for NeedlessBool {
@@ -66,14 +62,13 @@ impl Violation for NeedlessBool {
 
     #[derive_message_formats]
     fn message(&self) -> String {
-        let NeedlessBool { condition, .. } = self;
+        let NeedlessBool { condition } = self;
         format!("Return the condition `{condition}` directly")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable.then_some(|NeedlessBool { condition, .. }| {
+        let NeedlessBool { condition } = self;
-            format!("Replace with `return {condition}`")
+        Some(format!("Replace with `return {condition}`"))
-        })
     }
 }
 
@@ -110,7 +105,6 @@ impl Violation for IfElseBlockInsteadOfDictLookup {
 #[violation]
 pub struct IfElseBlockInsteadOfIfExp {
     contents: String,
-    fixable: bool,
 }
 
 impl Violation for IfElseBlockInsteadOfIfExp {
@@ -118,15 +112,13 @@ impl Violation for IfElseBlockInsteadOfIfExp {
 
     #[derive_message_formats]
     fn message(&self) -> String {
-        let IfElseBlockInsteadOfIfExp { contents, .. } = self;
+        let IfElseBlockInsteadOfIfExp { contents } = self;
         format!("Use ternary operator `{contents}` instead of `if`-`else`-block")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let IfElseBlockInsteadOfIfExp { contents } = self;
-            .then_some(|IfElseBlockInsteadOfIfExp { contents, .. }| {
+        Some(format!("Replace `if`-`else`-block with `{contents}`"))
-                format!("Replace `if`-`else`-block with `{contents}`")
-            })
     }
 }
 
@@ -163,7 +155,6 @@ impl Violation for IfWithSameArms {
 #[violation]
 pub struct IfElseBlockInsteadOfDictGet {
     contents: String,
-    fixable: bool,
 }
 
 impl Violation for IfElseBlockInsteadOfDictGet {
@@ -171,15 +162,13 @@ impl Violation for IfElseBlockInsteadOfDictGet {
 
     #[derive_message_formats]
     fn message(&self) -> String {
-        let IfElseBlockInsteadOfDictGet { contents, .. } = self;
+        let IfElseBlockInsteadOfDictGet { contents } = self;
         format!("Use `{contents}` instead of an `if` block")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let IfElseBlockInsteadOfDictGet { contents } = self;
-            .then_some(|IfElseBlockInsteadOfDictGet { contents, .. }| {
+        Some(format!("Replace with `{contents}`"))
-                format!("Replace with `{contents}`")
-            })
     }
 }
 
@@ -289,7 +278,7 @@ pub fn nested_if_statements(
     );
 
     let mut diagnostic = Diagnostic::new(
-        CollapsibleIf { fixable },
+        CollapsibleIf,
         colon.map_or_else(
             || stmt.range(),
             |colon| TextRange::new(stmt.start(), colon.end()),
@@ -367,7 +356,7 @@ pub fn needless_bool(checker: &mut Checker, stmt: &Stmt) {
         && !has_comments(stmt, checker.locator)
         && (matches!(test.node, ExprKind::Compare { .. }) || checker.ctx.is_builtin("bool"));
 
-    let mut diagnostic = Diagnostic::new(NeedlessBool { condition, fixable }, stmt.range());
+    let mut diagnostic = Diagnostic::new(NeedlessBool { condition }, stmt.range());
     if fixable && checker.patch(diagnostic.kind.rule()) {
         if matches!(test.node, ExprKind::Compare { .. }) {
             // If the condition is a comparison, we can replace it with the condition.
@@ -526,7 +515,6 @@ pub fn use_ternary_operator(checker: &mut Checker, stmt: &Stmt, parent: Option<&
     let mut diagnostic = Diagnostic::new(
         IfElseBlockInsteadOfIfExp {
             contents: contents.clone(),
-            fixable,
         },
         stmt.range(),
     );
@@ -877,7 +865,6 @@ pub fn use_dict_get_with_default(
     let mut diagnostic = Diagnostic::new(
         IfElseBlockInsteadOfDictGet {
             contents: contents.clone(),
-            fixable,
         },
         stmt.range(),
     );

crates/ruff/src/rules/flake8_simplify/rules/ast_ifexp.rs

@@ -21,11 +21,9 @@ impl Violation for IfExprWithTrueFalse {
         format!("Use `bool({expr})` instead of `True if {expr} else False`")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|violation| {
+        let IfExprWithTrueFalse { expr } = self;
-            let IfExprWithTrueFalse { expr } = violation;
+        Some(format!("Replace with `not {expr}"))
-            format!("Replace with `not {expr}")
-        })
     }
 }
 

crates/ruff/src/rules/flake8_simplify/rules/ast_with.rs

@@ -42,9 +42,7 @@ use super::fix_with;
 /// ## References
 /// - [Python: "The with statement"](https://docs.python.org/3/reference/compound_stmts.html#the-with-statement)
 #[violation]
-pub struct MultipleWithStatements {
+pub struct MultipleWithStatements;
-    fixable: bool,
-}
 
 impl Violation for MultipleWithStatements {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
@@ -57,9 +55,8 @@ impl Violation for MultipleWithStatements {
         )
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        Some("Combine `with` statements".to_string())
-            .then_some(|_| format!("Combine `with` statements"))
     }
 }
 
@@ -99,7 +96,7 @@ pub fn multiple_with_statements(
             checker.locator,
         );
         let mut diagnostic = Diagnostic::new(
-            MultipleWithStatements { fixable },
+            MultipleWithStatements,
             colon.map_or_else(
                 || with_stmt.range(),
                 |colon| TextRange::new(with_stmt.start(), colon.end()),

crates/ruff/src/rules/flake8_simplify/rules/reimplemented_builtin.rs

@@ -26,11 +26,9 @@ impl Violation for ReimplementedBuiltin {
         format!("Use `{repl}` instead of `for` loop")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|violation| {
+        let ReimplementedBuiltin { repl } = self;
-            let ReimplementedBuiltin { repl } = violation;
+        Some(format!("Replace with `{repl}`"))
-            format!("Replace with `{repl}`")
-        })
     }
 }
 

crates/ruff/src/rules/flake8_simplify/rules/suppressible_exception.rs

@@ -28,11 +28,9 @@ impl Violation for SuppressibleException {
         format!("Use `contextlib.suppress({exception})` instead of `try`-`except`-`pass`")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let SuppressibleException { exception, .. } = self;
-            .then_some(|SuppressibleException { exception, .. }| {
+        Some(format!("Replace with `contextlib.suppress({exception})`"))
-                format!("Replace with `contextlib.suppress({exception})`")
-            })
     }
 }
 

crates/ruff/src/rules/flake8_simplify/rules/yoda_conditions.rs

@@ -29,16 +29,11 @@ impl Violation for YodaConditions {
         }
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
         let YodaConditions { suggestion } = self;
-        if suggestion.is_some() {
+        suggestion
-            Some(|YodaConditions { suggestion }| {
+            .as_ref()
-                let suggestion = suggestion.as_ref().unwrap();
+            .map(|suggestion| format!("Replace Yoda condition with `{suggestion}`"))
-                format!("Replace Yoda condition with `{suggestion}`")
-            })
-        } else {
-            None
-        }
     }
 }
 

crates/ruff/src/rules/flake8_simplify/snapshots/ruff__rules__flake8_simplify__tests__SIM101_SIM101.py.snap

@@ -144,5 +144,6 @@ SIM101.py:22:4: SIM101 Multiple `isinstance` calls for expression, merge into a
    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ SIM101
 25 |     pass
    |
+   = help: Merge `isinstance` calls
 
 

crates/ruff/src/rules/flake8_simplify/snapshots/ruff__rules__flake8_simplify__tests__SIM102_SIM102.py.snap

@@ -81,6 +81,7 @@ SIM102.py:20:1: SIM102 Use a single `if` statement instead of nested `if` statem
    | |_________^ SIM102
 24 |           c
    |
+   = help: Combine `if` statements using `and`
 
 SIM102.py:26:1: SIM102 [*] Use a single `if` statement instead of nested `if` statements
    |

crates/ruff/src/rules/flake8_simplify/snapshots/ruff__rules__flake8_simplify__tests__SIM103_SIM103.py.snap

@@ -115,6 +115,7 @@ SIM103.py:57:5: SIM103 Return the condition `a` directly
 62 | |         return True
    | |___________________^ SIM103
    |
+   = help: Replace with `return a`
 
 SIM103.py:83:5: SIM103 Return the condition `a` directly
    |
@@ -127,5 +128,6 @@ SIM103.py:83:5: SIM103 Return the condition `a` directly
 88 | |         return False
    | |____________________^ SIM103
    |
+   = help: Replace with `return a`
 
 

crates/ruff/src/rules/flake8_simplify/snapshots/ruff__rules__flake8_simplify__tests__SIM105_SIM105_0.py.snap

@@ -175,5 +175,6 @@ SIM105_0.py:93:5: SIM105 Use `contextlib.suppress(ValueError, OSError)` instead
 97 | |         pass  # Trailing comment.
    | |____________^ SIM105
    |
+   = help: Replace with `contextlib.suppress(ValueError, OSError)`
 
 

crates/ruff/src/rules/flake8_simplify/snapshots/ruff__rules__flake8_simplify__tests__SIM108_SIM108.py.snap

@@ -36,6 +36,7 @@ SIM108.py:58:1: SIM108 Use ternary operator `abc = x if x > 0 else -x` instead o
 64 | |     abc = -x
    | |____________^ SIM108
    |
+   = help: Replace `if`-`else`-block with `abc = x if x > 0 else -x`
 
 SIM108.py:82:1: SIM108 [*] Use ternary operator `b = cccccccccccccccccccccccccccccccccccc if a else ddddddddddddddddddddddddddddddddddddd` instead of `if`-`else`-block
    |
@@ -70,6 +71,7 @@ SIM108.py:97:1: SIM108 Use ternary operator `exitcode = 0 if True else 1` instea
 101 | |     exitcode = 1  # Trailing comment
     | |________________^ SIM108
     |
+    = help: Replace `if`-`else`-block with `exitcode = 0 if True else 1`
 
 SIM108.py:104:1: SIM108 Use ternary operator `x = 3 if True else 5` instead of `if`-`else`-block
     |
@@ -78,6 +80,7 @@ SIM108.py:104:1: SIM108 Use ternary operator `x = 3 if True else 5` instead of `
 106 | | else: x = 5
     | |___________^ SIM108
     |
+    = help: Replace `if`-`else`-block with `x = 3 if True else 5`
 
 SIM108.py:109:1: SIM108 Use ternary operator `x = 3 if True else 5` instead of `if`-`else`-block
     |
@@ -88,5 +91,6 @@ SIM108.py:109:1: SIM108 Use ternary operator `x = 3 if True else 5` instead of `
 113 | |     x = 5
     | |_________^ SIM108
     |
+    = help: Replace `if`-`else`-block with `x = 3 if True else 5`
 
 

crates/ruff/src/rules/flake8_simplify/snapshots/ruff__rules__flake8_simplify__tests__SIM117_SIM117.py.snap

@@ -57,6 +57,7 @@ SIM117.py:13:1: SIM117 Use a single `with` statement with multiple contexts inst
    | |__________________^ SIM117
 17 |           print("hello")
    |
+   = help: Combine `with` statements
 
 SIM117.py:19:1: SIM117 [*] Use a single `with` statement with multiple contexts instead of nested `with` statements
    |

crates/ruff/src/rules/flake8_tidy_imports/relative_imports.rs

@@ -73,12 +73,13 @@ impl Violation for RelativeImports {
         }
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|RelativeImports { strictness }| match strictness {
+        let RelativeImports { strictness } = self;
+        Some(match strictness {
             Strictness::Parents => {
-                format!("Replace relative imports from parent modules with absolute imports")
+                "Replace relative imports from parent modules with absolute imports".to_string()
             }
-            Strictness::All => format!("Replace relative imports with absolute imports"),
+            Strictness::All => "Replace relative imports with absolute imports".to_string(),
         })
     }
 }

crates/ruff/src/rules/isort/rules/organize_imports.rs

@@ -48,8 +48,8 @@ impl Violation for UnsortedImports {
         format!("Import block is un-sorted or un-formatted")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|_| "Organize imports".to_string())
+        Some("Organize imports".to_string())
     }
 }
 

crates/ruff/src/rules/pandas_vet/rules/inplace_argument.rs

@@ -32,9 +32,7 @@ use crate::rules::pandas_vet::fixes::convert_inplace_argument_to_assignment;
 /// ## References
 /// - [_Why You Should Probably Never Use pandas inplace=True_](https://towardsdatascience.com/why-you-should-probably-never-use-pandas-inplace-true-9f9f211849e4)
 #[violation]
-pub struct PandasUseOfInplaceArgument {
+pub struct PandasUseOfInplaceArgument;
-    fixable: bool,
-}
 
 impl Violation for PandasUseOfInplaceArgument {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
@@ -44,9 +42,8 @@ impl Violation for PandasUseOfInplaceArgument {
         format!("`inplace=True` should be avoided; it has inconsistent behavior")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        Some("Assign to variable; remove `inplace` arg".to_string())
-            .then_some(|_| format!("Assign to variable; remove `inplace` arg"))
     }
 }
 
@@ -85,8 +82,7 @@ pub fn inplace_argument(
                     && matches!(checker.ctx.stmt().node, StmtKind::Expr { .. })
                     && checker.ctx.expr_parent().is_none()
                     && !checker.ctx.scope().kind.is_lambda();
-                let mut diagnostic =
+                let mut diagnostic = Diagnostic::new(PandasUseOfInplaceArgument, keyword.range());
-                    Diagnostic::new(PandasUseOfInplaceArgument { fixable }, keyword.range());
                 if fixable && checker.patch(diagnostic.kind.rule()) {
                     if let Some(fix) = convert_inplace_argument_to_assignment(
                         checker.locator,

crates/ruff/src/rules/pandas_vet/snapshots/ruff__rules__pandas_vet__tests__PD002_PD002.py.snap

@@ -114,6 +114,7 @@ PD002.py:23:23: PD002 `inplace=True` should be avoided; it has inconsistent beha
    |                       ^^^^^^^^^^^^ PD002
 25 | f(x.drop(["a"], axis=1, inplace=True))
    |
+   = help: Assign to variable; remove `inplace` arg
 
 PD002.py:24:25: PD002 `inplace=True` should be avoided; it has inconsistent behavior
    |
@@ -124,6 +125,7 @@ PD002.py:24:25: PD002 `inplace=True` should be avoided; it has inconsistent beha
 27 | 
 28 | x.apply(lambda x: x.sort_values('a', inplace=True))
    |
+   = help: Assign to variable; remove `inplace` arg
 
 PD002.py:26:38: PD002 `inplace=True` should be avoided; it has inconsistent behavior
    |
@@ -132,5 +134,6 @@ PD002.py:26:38: PD002 `inplace=True` should be avoided; it has inconsistent beha
 28 | x.apply(lambda x: x.sort_values('a', inplace=True))
    |                                      ^^^^^^^^^^^^ PD002
    |
+   = help: Assign to variable; remove `inplace` arg
 
 

crates/ruff/src/rules/pycodestyle/rules/lambda_assignment.rs

@@ -39,7 +39,6 @@ use crate::registry::AsRule;
 #[violation]
 pub struct LambdaAssignment {
     name: String,
-    fixable: bool,
 }
 
 impl Violation for LambdaAssignment {
@@ -50,9 +49,9 @@ impl Violation for LambdaAssignment {
         format!("Do not assign a `lambda` expression, use a `def`")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let LambdaAssignment { name } = self;
-            .then_some(|LambdaAssignment { name, .. }| format!("Rewrite `{name}` as a `def`"))
+        Some(format!("Rewrite `{name}` as a `def`"))
     }
 }
 
@@ -77,7 +76,6 @@ pub fn lambda_assignment(
             let mut diagnostic = Diagnostic::new(
                 LambdaAssignment {
                     name: id.to_string(),
-                    fixable,
                 },
                 stmt.range(),
             );

crates/ruff/src/rules/pycodestyle/snapshots/ruff__rules__pycodestyle__tests__E731_E731.py.snap

@@ -115,6 +115,7 @@ E731.py:14:5: E731 Do not assign a `lambda` expression, use a `def`
 16 |     f = lambda x: 2 * x
    |     ^^^^^^^^^^^^^^^^^^^ E731
    |
+   = help: Rewrite `f` as a `def`
 
 E731.py:32:1: E731 [*] Do not assign a `lambda` expression, use a `def`
    |

crates/ruff/src/rules/pydocstyle/rules/blank_after_summary.rs

@@ -11,9 +11,6 @@ pub struct BlankLineAfterSummary {
     num_lines: usize,
 }
 
-fn fmt_blank_line_after_summary_autofix_msg(_: &BlankLineAfterSummary) -> String {
-    "Insert single blank line".to_string()
-}
 impl Violation for BlankLineAfterSummary {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
 
@@ -29,12 +26,8 @@ impl Violation for BlankLineAfterSummary {
         }
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        let BlankLineAfterSummary { num_lines } = self;
+        Some("Insert single blank line".to_string())
-        if *num_lines > 0 {
-            return Some(fmt_blank_line_after_summary_autofix_msg);
-        }
-        None
     }
 }
 

crates/ruff/src/rules/pydocstyle/rules/no_surrounding_whitespace.rs

@@ -19,8 +19,8 @@ impl Violation for SurroundingWhitespace {
         format!("No whitespaces allowed surrounding docstring text")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|_| "Trim surrounding whitespace".to_string())
+        Some("Trim surrounding whitespace".to_string())
     }
 }
 

crates/ruff/src/rules/pydocstyle/rules/one_liner.rs

@@ -18,8 +18,8 @@ impl Violation for FitsOnOneLine {
         format!("One-line docstring should fit on one line")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|_| "Reformat to one line".to_string())
+        Some("Reformat to one line".to_string())
     }
 }
 

crates/ruff/src/rules/pydocstyle/snapshots/ruff__rules__pydocstyle__tests__D205_D.py.snap

@@ -12,6 +12,7 @@ D.py:200:5: D205 1 blank line required between summary line and description
 205 | |     """
     | |_______^ D205
     |
+    = help: Insert single blank line
 
 D.py:210:5: D205 [*] 1 blank line required between summary line and description (found 2)
     |

crates/ruff/src/rules/pyflakes/rules/imports.rs

@@ -44,17 +44,14 @@ impl Violation for UnusedImport {
         }
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        let UnusedImport { context, .. } = self;
+        let UnusedImport { name, multiple, .. } = self;
-        context
+
-            .is_none()
+        Some(if *multiple {
-            .then_some(|UnusedImport { name, multiple, .. }| {
+            "Remove unused import".to_string()
-                if *multiple {
+        } else {
-                    "Remove unused import".to_string()
+            format!("Remove unused import: `{name}`")
-                } else {
+        })
-                    format!("Remove unused import: `{name}`")
-                }
-            })
     }
 }
 #[violation]

crates/ruff/src/rules/pyflakes/rules/repeated_keys.rs

@@ -26,12 +26,13 @@ impl Violation for MultiValueRepeatedKeyLiteral {
         format!("Dictionary key literal `{name}` repeated")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        let MultiValueRepeatedKeyLiteral { repeated_value, .. } = self;
+        let MultiValueRepeatedKeyLiteral {
+            repeated_value,
+            name,
+        } = self;
         if *repeated_value {
-            Some(|MultiValueRepeatedKeyLiteral { name, .. }| {
+            Some(format!("Remove repeated key literal `{name}`"))
-                format!("Remove repeated key literal `{name}`")
-            })
         } else {
             None
         }
@@ -52,12 +53,13 @@ impl Violation for MultiValueRepeatedKeyVariable {
         format!("Dictionary key `{name}` repeated")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        let MultiValueRepeatedKeyVariable { repeated_value, .. } = self;
+        let MultiValueRepeatedKeyVariable {
+            repeated_value,
+            name,
+        } = self;
         if *repeated_value {
-            Some(|MultiValueRepeatedKeyVariable { name, .. }| {
+            Some(format!("Remove repeated key `{name}`"))
-                format!("Remove repeated key `{name}`")
-            })
         } else {
             None
         }

crates/ruff/src/rules/pyflakes/rules/unused_variable.rs

@@ -57,11 +57,9 @@ impl Violation for UnusedVariable {
         format!("Local variable `{name}` is assigned to but never used")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|violation| {
+        let UnusedVariable { name } = self;
-            let UnusedVariable { name } = violation;
+        Some(format!("Remove assignment to unused variable `{name}`"))
-            format!("Remove assignment to unused variable `{name}`")
-        })
     }
 }
 

crates/ruff/src/rules/pyflakes/snapshots/ruff__rules__pyflakes__tests__F401_F401_10.py.snap

@@ -10,6 +10,7 @@ F401_10.py:6:16: F401 `orjson` imported but unused; consider using `importlib.ut
  9 | 
 10 |         return True
    |
+   = help: Remove unused import: `orjson`
 
 F401_10.py:15:16: F401 [*] `orjson` imported but unused
    |

crates/ruff/src/rules/pylint/rules/manual_import_from.rs

@@ -11,7 +11,6 @@ use crate::registry::AsRule;
 pub struct ManualFromImport {
     module: String,
     name: String,
-    fixable: bool,
 }
 
 impl Violation for ManualFromImport {
@@ -19,15 +18,13 @@ impl Violation for ManualFromImport {
 
     #[derive_message_formats]
     fn message(&self) -> String {
-        let ManualFromImport { module, name, .. } = self;
+        let ManualFromImport { module, name } = self;
         format!("Use `from {module} import {name}` in lieu of alias")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let ManualFromImport { module, name } = self;
-            .then_some(|ManualFromImport { module, name, .. }| {
+        Some(format!("Replace with `from {module} import {name}`"))
-                format!("Replace with `from {module} import {name}`")
-            })
     }
 }
 
@@ -48,7 +45,6 @@ pub fn manual_from_import(checker: &mut Checker, stmt: &Stmt, alias: &Alias, nam
         ManualFromImport {
             module: module.to_string(),
             name: name.to_string(),
-            fixable,
         },
         alias.range(),
     );

crates/ruff/src/rules/pylint/rules/nested_min_max.rs

@@ -1,4 +1,4 @@
-use ruff_text_size::TextSize;
+use ruff_text_size::TextRange;
 use rustpython_parser::ast::{Expr, ExprKind, Keyword};
 
 use ruff_diagnostics::{AutofixKind, Diagnostic, Edit, Fix, Violation};
@@ -17,7 +17,6 @@ pub enum MinMax {
 #[violation]
 pub struct NestedMinMax {
     func: MinMax,
-    fixable: bool,
 }
 
 impl Violation for NestedMinMax {
@@ -28,9 +27,9 @@ impl Violation for NestedMinMax {
         format!("Nested `{}` calls can be flattened", self.func)
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let NestedMinMax { func } = self;
-            .then_some(|NestedMinMax { func, .. }| format!("Flatten nested `{func}` calls"))
+        Some(format!("Flatten nested `{func}` calls"))
     }
 }
 
@@ -106,22 +105,15 @@ pub fn nested_min_max(
         MinMax::try_from_call(func, keywords, &checker.ctx) == Some(min_max)
     }) {
         let fixable = !has_comments(expr, checker.locator);
-        let mut diagnostic = Diagnostic::new(
+        let mut diagnostic = Diagnostic::new(NestedMinMax { func: min_max }, expr.range());
-            NestedMinMax {
-                func: min_max,
-                fixable,
-            },
-            expr.range(),
-        );
         if fixable && checker.patch(diagnostic.kind.rule()) {
-            let flattened_expr = Expr::new(
+            let flattened_expr = Expr::with_range(
-                TextSize::default(),
-                TextSize::default(),
                 ExprKind::Call {
                     func: Box::new(func.clone()),
                     args: collect_nested_args(&checker.ctx, min_max, args),
                     keywords: keywords.to_owned(),
                 },
+                TextRange::default(),
             );
             #[allow(deprecated)]
             diagnostic.set_fix(Fix::unspecified(Edit::range_replacement(

crates/ruff/src/rules/pylint/rules/sys_exit_alias.rs

@@ -21,8 +21,9 @@ impl Violation for SysExitAlias {
         format!("Use `sys.exit()` instead of `{name}`")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|SysExitAlias { name }| format!("Replace `{name}` with `sys.exit()`"))
+        let SysExitAlias { name } = self;
+        Some(format!("Replace `{name}` with `sys.exit()`"))
     }
 }
 

crates/ruff/src/rules/pylint/snapshots/ruff__rules__pylint__tests__PLR0402_import_aliasing.py.snap

@@ -52,5 +52,6 @@ import_aliasing.py:12:8: PLR0402 Use `from foo.bar import foobar` in lieu of ali
 15 | import os
 16 | import os as OS
    |
+   = help: Replace with `from foo.bar import foobar`
 
 

crates/ruff/src/rules/pylint/snapshots/ruff__rules__pylint__tests__PLW3301_nested_min_max.py.snap

@@ -192,5 +192,6 @@ nested_min_max.py:18:1: PLW3301 Nested `min` calls can be flattened
 22 | | )
    | |_^ PLW3301
    |
+   = help: Flatten nested `min` calls
 
 

crates/ruff/src/rules/pyupgrade/rules/convert_named_tuple_functional_to_class.rs

@@ -14,7 +14,6 @@ use crate::registry::AsRule;
 #[violation]
 pub struct ConvertNamedTupleFunctionalToClass {
     name: String,
-    fixable: bool,
 }
 
 impl Violation for ConvertNamedTupleFunctionalToClass {
@@ -22,15 +21,14 @@ impl Violation for ConvertNamedTupleFunctionalToClass {
 
     #[derive_message_formats]
     fn message(&self) -> String {
-        let ConvertNamedTupleFunctionalToClass { name, .. } = self;
+        let ConvertNamedTupleFunctionalToClass { name } = self;
         format!("Convert `{name}` from `NamedTuple` functional to class syntax")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let ConvertNamedTupleFunctionalToClass { name } = self;
-            .then_some(|ConvertNamedTupleFunctionalToClass { name, .. }| {
+
-                format!("Convert `{name}` to class syntax")
+        Some(format!("Convert `{name}` to class syntax"))
-            })
     }
 }
 
@@ -197,7 +195,6 @@ pub fn convert_named_tuple_functional_to_class(
     let mut diagnostic = Diagnostic::new(
         ConvertNamedTupleFunctionalToClass {
             name: typename.to_string(),
-            fixable,
         },
         stmt.range(),
     );

crates/ruff/src/rules/pyupgrade/rules/convert_typed_dict_functional_to_class.rs

@@ -26,11 +26,9 @@ impl Violation for ConvertTypedDictFunctionalToClass {
         format!("Convert `{name}` from `TypedDict` functional to class syntax")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let ConvertTypedDictFunctionalToClass { name, .. } = self;
-            .then_some(|ConvertTypedDictFunctionalToClass { name, .. }| {
+        Some(format!("Convert `{name}` to class syntax"))
-                format!("Convert `{name}` to class syntax")
-            })
     }
 }
 

crates/ruff/src/rules/pyupgrade/rules/datetime_utc_alias.rs

@@ -20,12 +20,8 @@ impl Violation for DatetimeTimezoneUTC {
         format!("Use `datetime.UTC` alias")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        if self.straight_import {
+        Some("Convert to `datetime.UTC` alias".to_string())
-            Some(|_| "Convert to `datetime.UTC` alias".to_string())
-        } else {
-            None
-        }
     }
 }
 

crates/ruff/src/rules/pyupgrade/rules/deprecated_import.rs

@@ -62,14 +62,9 @@ impl Violation for DeprecatedImport {
         }
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        if let Deprecation::WithoutRename(WithoutRename { fixable, .. }) = self.deprecation {
+        if let Deprecation::WithoutRename(WithoutRename { target, .. }) = &self.deprecation {
-            fixable.then_some(|DeprecatedImport { deprecation }| {
+            Some(format!("Import from `{target}`"))
-                let Deprecation::WithoutRename(WithoutRename { target, .. }) = deprecation else {
-                    unreachable!();
-                };
-                format!("Import from `{target}`")
-            })
         } else {
             None
         }

crates/ruff/src/rules/pyupgrade/rules/format_literals.rs

@@ -24,8 +24,8 @@ impl Violation for FormatLiterals {
         format!("Use implicit references for positional format fields")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(|_| "Remove explicit positional indices".to_string())
+        Some("Remove explicit positional indices".to_string())
     }
 }
 

crates/ruff/src/rules/pyupgrade/rules/open_alias.rs

@@ -7,9 +7,7 @@ use crate::checkers::ast::Checker;
 use crate::registry::AsRule;
 
 #[violation]
-pub struct OpenAlias {
+pub struct OpenAlias;
-    fixable: bool,
-}
 
 impl Violation for OpenAlias {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
@@ -19,9 +17,8 @@ impl Violation for OpenAlias {
         format!("Use builtin `open`")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        Some("Replace with builtin `open`".to_string())
-            .then_some(|_| format!("Replace with builtin `open`"))
     }
 }
 
@@ -36,7 +33,7 @@ pub fn open_alias(checker: &mut Checker, expr: &Expr, func: &Expr) {
             .ctx
             .find_binding("open")
             .map_or(true, |binding| binding.kind.is_builtin());
-        let mut diagnostic = Diagnostic::new(OpenAlias { fixable }, expr.range());
+        let mut diagnostic = Diagnostic::new(OpenAlias, expr.range());
         if fixable && checker.patch(diagnostic.kind.rule()) {
             #[allow(deprecated)]
             diagnostic.set_fix(Fix::unspecified(Edit::range_replacement(

crates/ruff/src/rules/pyupgrade/rules/use_pep585_annotation.rs

@@ -10,7 +10,6 @@ use crate::registry::AsRule;
 #[violation]
 pub struct NonPEP585Annotation {
     name: String,
-    fixable: bool,
 }
 
 impl Violation for NonPEP585Annotation {
@@ -18,7 +17,7 @@ impl Violation for NonPEP585Annotation {
 
     #[derive_message_formats]
     fn message(&self) -> String {
-        let NonPEP585Annotation { name, .. } = self;
+        let NonPEP585Annotation { name } = self;
         format!(
             "Use `{}` instead of `{}` for type annotations",
             name.to_lowercase(),
@@ -26,10 +25,9 @@ impl Violation for NonPEP585Annotation {
         )
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable.then_some(|NonPEP585Annotation { name, .. }| {
+        let NonPEP585Annotation { name } = self;
-            format!("Replace `{name}` with `{}`", name.to_lowercase())
+        Some(format!("Replace `{name}` with `{}`", name.to_lowercase()))
-        })
     }
 }
 
@@ -48,7 +46,6 @@ pub fn use_pep585_annotation(checker: &mut Checker, expr: &Expr) {
         let mut diagnostic = Diagnostic::new(
             NonPEP585Annotation {
                 name: binding.to_string(),
-                fixable,
             },
             expr.range(),
         );

crates/ruff/src/rules/pyupgrade/rules/use_pep604_annotation.rs

@@ -10,9 +10,7 @@ use crate::checkers::ast::Checker;
 use crate::registry::AsRule;
 
 #[violation]
-pub struct NonPEP604Annotation {
+pub struct NonPEP604Annotation;
-    fixable: bool,
-}
 
 impl Violation for NonPEP604Annotation {
     const AUTOFIX: AutofixKind = AutofixKind::Sometimes;
@@ -22,8 +20,8 @@ impl Violation for NonPEP604Annotation {
         format!("Use `X | Y` for type annotations")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable.then_some(|_| format!("Convert to `X | Y`"))
+        Some("Convert to `X | Y`".to_string())
     }
 }
 
@@ -110,7 +108,7 @@ pub fn use_pep604_annotation(checker: &mut Checker, expr: &Expr, value: &Expr, s
 
     match typing_member {
         TypingMember::Optional => {
-            let mut diagnostic = Diagnostic::new(NonPEP604Annotation { fixable }, expr.range());
+            let mut diagnostic = Diagnostic::new(NonPEP604Annotation, expr.range());
             if fixable && checker.patch(diagnostic.kind.rule()) {
                 #[allow(deprecated)]
                 diagnostic.set_fix(Fix::unspecified(Edit::range_replacement(
@@ -121,7 +119,7 @@ pub fn use_pep604_annotation(checker: &mut Checker, expr: &Expr, value: &Expr, s
             checker.diagnostics.push(diagnostic);
         }
         TypingMember::Union => {
-            let mut diagnostic = Diagnostic::new(NonPEP604Annotation { fixable }, expr.range());
+            let mut diagnostic = Diagnostic::new(NonPEP604Annotation, expr.range());
             if fixable && checker.patch(diagnostic.kind.rule()) {
                 match &slice.node {
                     ExprKind::Slice { .. } => {

crates/ruff/src/rules/pyupgrade/snapshots/ruff__rules__pyupgrade__tests__UP006.py.snap

@@ -151,6 +151,7 @@ UP006.py:45:10: UP006 Use `list` instead of `List` for type annotations
    |          ^^^^^^^^^^^^^^ UP006
 46 |     ...
    |
+   = help: Replace `List` with `list`
 
 UP006.py:49:11: UP006 [*] Use `list` instead of `List` for type annotations
    |
@@ -212,6 +213,7 @@ UP006.py:53:16: UP006 Use `list` instead of `List` for type annotations
    |                ^^^^^^^^^^^^^^ UP006
 54 |     ...
    |
+   = help: Replace `List` with `list`
 
 UP006.py:57:10: UP006 Use `list` instead of `List` for type annotations
    |
@@ -219,6 +221,7 @@ UP006.py:57:10: UP006 Use `list` instead of `List` for type annotations
    |          ^^^^^^^^^^^^^^^^^^^^^^ UP006
 58 |     ...
    |
+   = help: Replace `List` with `list`
 
 UP006.py:57:10: UP006 Use `list` instead of `List` for type annotations
    |
@@ -226,5 +229,6 @@ UP006.py:57:10: UP006 Use `list` instead of `List` for type annotations
    |          ^^^^^^^^^^^^^^^^^^^^^^ UP006
 58 |     ...
    |
+   = help: Replace `List` with `list`
 
 

crates/ruff/src/rules/pyupgrade/snapshots/ruff__rules__pyupgrade__tests__UP007.py.snap

@@ -209,6 +209,7 @@ UP007.py:48:9: UP007 Use `X | Y` for type annotations
 51 | 
 52 |     x = Union[str, int]
    |
+   = help: Convert to `X | Y`
 
 UP007.py:50:9: UP007 Use `X | Y` for type annotations
    |
@@ -219,6 +220,7 @@ UP007.py:50:9: UP007 Use `X | Y` for type annotations
 53 |     x = Union["str", "int"]
 54 |     x: Union[str, int]
    |
+   = help: Convert to `X | Y`
 
 UP007.py:52:8: UP007 [*] Use `X | Y` for type annotations
    |

crates/ruff/src/rules/pyupgrade/snapshots/ruff__rules__pyupgrade__tests__UP020.py.snap

@@ -28,5 +28,6 @@ UP020.py:8:6: UP020 Use builtin `open`
    |      ^^^^^^^^^^^^^ UP020
 11 |     print(f.read())
    |
+   = help: Replace with builtin `open`
 
 

crates/ruff/src/rules/pyupgrade/snapshots/ruff__rules__pyupgrade__tests__UP035.py.snap

@@ -418,5 +418,6 @@ UP035.py:46:10: UP035 Import from `collections.abc` instead: `Mapping`
 50 |   
 51 |   # OK
    |
+   = help: Import from `collections.abc`
 
 

crates/ruff/src/rules/pyupgrade/snapshots/ruff__rules__pyupgrade__tests__datetime_utc_alias_py311.snap

@@ -8,6 +8,7 @@ UP017.py:7:7: UP017 Use `datetime.UTC` alias
   |       ^^^^^^^^^^^^ UP017
 9 | print(tz.utc)
   |
+  = help: Convert to `datetime.UTC` alias
 
 UP017.py:8:7: UP017 Use `datetime.UTC` alias
    |
@@ -18,6 +19,7 @@ UP017.py:8:7: UP017 Use `datetime.UTC` alias
 11 | 
 12 | print(datetime.timezone.utc)
    |
+   = help: Convert to `datetime.UTC` alias
 
 UP017.py:10:7: UP017 [*] Use `datetime.UTC` alias
    |
@@ -43,5 +45,6 @@ UP017.py:11:7: UP017 Use `datetime.UTC` alias
 12 | print(dt.timezone.utc)
    |       ^^^^^^^^^^^^^^^ UP017
    |
+   = help: Convert to `datetime.UTC` alias
 
 

crates/ruff/src/rules/ruff/rules/collection_literal_concatenation.rs

@@ -10,7 +10,6 @@ use crate::registry::AsRule;
 #[violation]
 pub struct CollectionLiteralConcatenation {
     expr: String,
-    fixable: bool,
 }
 
 impl Violation for CollectionLiteralConcatenation {
@@ -18,15 +17,13 @@ impl Violation for CollectionLiteralConcatenation {
 
     #[derive_message_formats]
     fn message(&self) -> String {
-        let CollectionLiteralConcatenation { expr, .. } = self;
+        let CollectionLiteralConcatenation { expr } = self;
         format!("Consider `{expr}` instead of concatenation")
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        self.fixable
+        let CollectionLiteralConcatenation { expr } = self;
-            .then_some(|CollectionLiteralConcatenation { expr, .. }| {
+        Some(format!("Replace with `{expr}`"))
-                format!("Replace with `{expr}`")
-            })
     }
 }
 
@@ -102,7 +99,6 @@ pub fn collection_literal_concatenation(checker: &mut Checker, expr: &Expr) {
     let mut diagnostic = Diagnostic::new(
         CollectionLiteralConcatenation {
             expr: contents.clone(),
-            fixable,
         },
         expr.range(),
     );

crates/ruff/src/rules/ruff/snapshots/ruff__rules__ruff__tests__RUF005_RUF005.py.snap

@@ -226,6 +226,7 @@ RUF005.py:32:10: RUF005 Consider `[*first, 4, 5, 6]` instead of concatenation
 42 |   
 43 |   [] + foo + [
    |
+   = help: Replace with `[*first, 4, 5, 6]`
 
 RUF005.py:41:1: RUF005 [*] Consider `[*foo]` instead of concatenation
    |

crates/ruff_diagnostics/src/violation.rs

@@ -30,10 +30,13 @@ pub trait Violation: Debug + PartialEq + Eq {
         None
     }
 
-    /// If autofix is (potentially) available for this violation returns another
+    // TODO micha: Move `autofix_title` to `Fix`, add new `advice` method that is shown as an advice.
-    /// function that in turn can be used to obtain a string describing the
+    // Change the `Diagnostic` renderer to show the advice, and render the fix message after the `Suggested fix: <here>`
-    /// autofix.
+
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    /// Returns the title for the autofix. The message is also shown as an advice as part of the diagnostics.
+    ///
+    /// Required for rules that have autofixes.
+    fn autofix_title(&self) -> Option<String> {
         None
     }
 
@@ -72,8 +75,8 @@ impl<VA: AlwaysAutofixableViolation> Violation for VA {
         <Self as AlwaysAutofixableViolation>::explanation()
     }
 
-    fn autofix_title_formatter(&self) -> Option<fn(&Self) -> String> {
+    fn autofix_title(&self) -> Option<String> {
-        Some(Self::autofix_title)
+        Some(<Self as AlwaysAutofixableViolation>::autofix_title(self))
     }
 
     fn message_formats() -> &'static [&'static str] {

crates/ruff_macros/src/violation.rs

@@ -59,7 +59,7 @@ pub fn violation(violation: &ItemStruct) -> Result<TokenStream> {
 
                     Self {
                         body: Violation::message(&value),
-                        suggestion: value.autofix_title_formatter().map(|f| f(&value)),
+                        suggestion: Violation::autofix_title(&value),
                         name: stringify!(#ident).to_string(),
                     }
                 }
@@ -82,7 +82,7 @@ pub fn violation(violation: &ItemStruct) -> Result<TokenStream> {
 
                     Self {
                         body: Violation::message(&value),
-                        suggestion: value.autofix_title_formatter().map(|f| f(&value)),
+                        suggestion: Violation::autofix_title(&value),
                         name: stringify!(#ident).to_string(),
                     }
                 }