Auto merge of #13136 - xFrednet:07797-restriction-and-then, r=blyxyas

Make restriction lint's use `span_lint_and_then` (a -> e)

This migrates a few restriction lints to use `span_lint_and_then`. This change is motivated by #7797.

I'm also interested if it will have an impact on performance. With some of these lints, like [`clippy::implicit_return`](https://rust-lang.github.io/rust-clippy/master/index.html#/implicit_return) I expect an impact, as it was previously creating a suggestion **for every implicit return** which is just wild.

I've also cleaned up some lint message. Mostly minor stuff. For example: suggestions with a longer message than `"try"` now use `SuggestionStyle::ShowAlways`

---

`@blyxyas` Could you benchmark this PR? I want to get all the numbers :3

---

This also crashed our new lintcheck CI with the following message:

> Error: $GITHUB_STEP_SUMMARY upload aborted, supports content up to a size of 1024k, got 46731k. For more information see: https://docs.github.com/actions/using-workflows/workflow-commands-for-github-actions#adding-a-markdown-summary

Which is just wild. Like, I've [tested the first 20 lints](https://github.com/xFrednet/rust-clippy/actions/runs/10027528172) and got like four changes and then this. 50 MB of changed lint messages o.O. Looks like I'll create a separate PR to fix that step ^^

---

cc: #7797

changelog: none

r? `@blyxyas`

clippy_lints/src/as_conversions.rs

@@ -1,4 +1,4 @@
-use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::is_from_proc_macro;
 use rustc_hir::{Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
@@ -52,13 +52,15 @@ impl<'tcx> LateLintPass<'tcx> for AsConversions {
             && !in_external_macro(cx.sess(), expr.span)
             && !is_from_proc_macro(cx, expr)
         {
-            span_lint_and_help(
+            #[expect(clippy::collapsible_span_lint_calls, reason = "rust-clippy#7797")]
+            span_lint_and_then(
                 cx,
                 AS_CONVERSIONS,
                 expr.span,
                 "using a potentially dangerous silent `as` conversion",
-                None,
-                "consider using a safe wrapper for this conversion",
+                |diag| {
+                    diag.help("consider using a safe wrapper for this conversion");
+                },
             );
         }
     }

clippy_lints/src/assertions_on_result_states.rs

@@ -1,4 +1,4 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::macros::{find_assert_args, root_macro_call_first_node, PanicExpn};
 use clippy_utils::source::snippet_with_context;
 use clippy_utils::ty::{has_debug_impl, is_copy, is_type_diagnostic_item};
@@ -68,39 +68,28 @@ impl<'tcx> LateLintPass<'tcx> for AssertionsOnResultStates {
                     return;
                 }
             }
-            let semicolon = if is_expr_final_block_expr(cx.tcx, e) { ";" } else { "" };
-            let mut app = Applicability::MachineApplicable;
-            match method_segment.ident.as_str() {
+            let (message, replacement) = match method_segment.ident.as_str() {
                 "is_ok" if type_suitable_to_unwrap(cx, args.type_at(1)) => {
-                    span_lint_and_sugg(
-                        cx,
-                        ASSERTIONS_ON_RESULT_STATES,
-                        macro_call.span,
-                        "called `assert!` with `Result::is_ok`",
-                        "replace with",
-                        format!(
-                            "{}.unwrap(){semicolon}",
-                            snippet_with_context(cx, recv.span, condition.span.ctxt(), "..", &mut app).0
-                        ),
-                        app,
-                    );
+                    ("called `assert!` with `Result::is_ok`", "unwrap")
                 },
                 "is_err" if type_suitable_to_unwrap(cx, args.type_at(0)) => {
-                    span_lint_and_sugg(
-                        cx,
-                        ASSERTIONS_ON_RESULT_STATES,
-                        macro_call.span,
-                        "called `assert!` with `Result::is_err`",
-                        "replace with",
-                        format!(
-                            "{}.unwrap_err(){semicolon}",
-                            snippet_with_context(cx, recv.span, condition.span.ctxt(), "..", &mut app).0
-                        ),
-                        app,
-                    );
+                    ("called `assert!` with `Result::is_err`", "unwrap_err")
                 },
-                _ => (),
+                _ => return,
             };
+            span_lint_and_then(cx, ASSERTIONS_ON_RESULT_STATES, macro_call.span, message, |diag| {
+                let semicolon = if is_expr_final_block_expr(cx.tcx, e) { ";" } else { "" };
+                let mut app = Applicability::MachineApplicable;
+                diag.span_suggestion(
+                    macro_call.span,
+                    "replace with",
+                    format!(
+                        "{}.{replacement}(){semicolon}",
+                        snippet_with_context(cx, recv.span, condition.span.ctxt(), "..", &mut app).0
+                    ),
+                    app,
+                );
+            });
         }
     }
 }

clippy_lints/src/attrs/allow_attributes.rs

@@ -1,5 +1,5 @@
 use super::ALLOW_ATTRIBUTES;
-use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::is_from_proc_macro;
 use rustc_ast::{AttrStyle, Attribute};
 use rustc_errors::Applicability;
@@ -13,14 +13,14 @@ pub fn check<'cx>(cx: &LateContext<'cx>, attr: &'cx Attribute) {
         && let Some(ident) = attr.ident()
         && !is_from_proc_macro(cx, attr)
     {
-        span_lint_and_sugg(
-            cx,
-            ALLOW_ATTRIBUTES,
-            ident.span,
-            "#[allow] attribute found",
-            "replace it with",
-            "expect".into(),
-            Applicability::MachineApplicable,
-        );
+        #[expect(clippy::collapsible_span_lint_calls, reason = "rust-clippy#7797")]
+        span_lint_and_then(cx, ALLOW_ATTRIBUTES, ident.span, "#[allow] attribute found", |diag| {
+            diag.span_suggestion(
+                ident.span,
+                "replace it with",
+                "expect",
+                Applicability::MachineApplicable,
+            );
+        });
     }
 }

clippy_lints/src/attrs/allow_attributes_without_reason.rs

@@ -1,5 +1,5 @@
 use super::{Attribute, ALLOW_ATTRIBUTES_WITHOUT_REASON};
-use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::is_from_proc_macro;
 use rustc_ast::{MetaItemKind, NestedMetaItem};
 use rustc_lint::{LateContext, LintContext};
@@ -21,12 +21,14 @@ pub(super) fn check<'cx>(cx: &LateContext<'cx>, name: Symbol, items: &[NestedMet
         return;
     }
 
-    span_lint_and_help(
+    #[expect(clippy::collapsible_span_lint_calls, reason = "rust-clippy#7797")]
+    span_lint_and_then(
         cx,
         ALLOW_ATTRIBUTES_WITHOUT_REASON,
         attr.span,
         format!("`{}` attribute without specifying a reason", name.as_str()),
-        None,
-        "try adding a reason at the end with `, reason = \"..\"`",
+        |diag| {
+            diag.help("try adding a reason at the end with `, reason = \"..\"`");
+        },
     );
 }

clippy_lints/src/casts/fn_to_numeric_cast_any.rs

@@ -1,6 +1,6 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::source::snippet_with_applicability;
-use rustc_errors::Applicability;
+use rustc_errors::{Applicability, SuggestionStyle};
 use rustc_hir::Expr;
 use rustc_lint::LateContext;
 use rustc_middle::ty::{self, Ty};
@@ -14,21 +14,24 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>,
         _ => { /* continue to checks */ },
     }
 
-    match cast_from.kind() {
-        ty::FnDef(..) | ty::FnPtr(_) => {
-            let mut applicability = Applicability::MaybeIncorrect;
-            let from_snippet = snippet_with_applicability(cx, cast_expr.span, "..", &mut applicability);
+    if let ty::FnDef(..) | ty::FnPtr(_) = cast_from.kind() {
+        let mut applicability = Applicability::MaybeIncorrect;
+        let from_snippet = snippet_with_applicability(cx, cast_expr.span, "..", &mut applicability);
 
-            span_lint_and_sugg(
-                cx,
-                FN_TO_NUMERIC_CAST_ANY,
-                expr.span,
-                format!("casting function pointer `{from_snippet}` to `{cast_to}`"),
-                "did you mean to invoke the function?",
-                format!("{from_snippet}() as {cast_to}"),
-                applicability,
-            );
-        },
-        _ => {},
+        span_lint_and_then(
+            cx,
+            FN_TO_NUMERIC_CAST_ANY,
+            expr.span,
+            format!("casting function pointer `{from_snippet}` to `{cast_to}`"),
+            |diag| {
+                diag.span_suggestion_with_style(
+                    expr.span,
+                    "did you mean to invoke the function?",
+                    format!("{from_snippet}() as {cast_to}"),
+                    applicability,
+                    SuggestionStyle::ShowAlways,
+                );
+            },
+        );
     }
 }

clippy_lints/src/create_dir.rs

@@ -1,6 +1,6 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet;
-use rustc_errors::Applicability;
+use clippy_utils::diagnostics::span_lint_and_then;
+use clippy_utils::source::snippet_with_applicability;
+use rustc_errors::{Applicability, SuggestionStyle};
 use rustc_hir::{Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::declare_lint_pass;
@@ -39,14 +39,24 @@ impl LateLintPass<'_> for CreateDir {
             && let Some(def_id) = cx.qpath_res(path, func.hir_id).opt_def_id()
             && cx.tcx.is_diagnostic_item(sym::fs_create_dir, def_id)
         {
-            span_lint_and_sugg(
+            span_lint_and_then(
                 cx,
                 CREATE_DIR,
                 expr.span,
                 "calling `std::fs::create_dir` where there may be a better way",
-                "consider calling `std::fs::create_dir_all` instead",
-                format!("create_dir_all({})", snippet(cx, arg.span, "..")),
-                Applicability::MaybeIncorrect,
+                |diag| {
+                    let mut app = Applicability::MaybeIncorrect;
+                    diag.span_suggestion_with_style(
+                        expr.span,
+                        "consider calling `std::fs::create_dir_all` instead",
+                        format!(
+                            "create_dir_all({})",
+                            snippet_with_applicability(cx, arg.span, "..", &mut app)
+                        ),
+                        app,
+                        SuggestionStyle::ShowAlways,
+                    );
+                },
             );
         }
     }

clippy_lints/src/dbg_macro.rs

@@ -1,5 +1,5 @@
 use clippy_config::Conf;
-use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::is_in_test;
 use clippy_utils::macros::{macro_backtrace, MacroCall};
 use clippy_utils::source::snippet_with_applicability;
@@ -65,61 +65,67 @@ impl LateLintPass<'_> for DbgMacro {
             // allows `dbg!` in test code if allow-dbg-in-test is set to true in clippy.toml
             !(self.allow_dbg_in_tests && is_in_test(cx.tcx, expr.hir_id))
         {
-            let mut applicability = Applicability::MachineApplicable;
-
-            let (sugg_span, suggestion) = match expr.peel_drop_temps().kind {
-                // dbg!()
-                ExprKind::Block(..) => {
-                    // If the `dbg!` macro is a "free" statement and not contained within other expressions,
-                    // remove the whole statement.
-                    if let Node::Stmt(_) = cx.tcx.parent_hir_node(expr.hir_id)
-                        && let Some(semi_span) = cx.sess().source_map().mac_call_stmt_semi_span(macro_call.span)
-                    {
-                        (macro_call.span.to(semi_span), String::new())
-                    } else {
-                        (macro_call.span, String::from("()"))
-                    }
-                },
-                // dbg!(1)
-                ExprKind::Match(val, ..) => (
-                    macro_call.span,
-                    snippet_with_applicability(cx, val.span.source_callsite(), "..", &mut applicability).to_string(),
-                ),
-                // dbg!(2, 3)
-                ExprKind::Tup(
-                    [
-                        Expr {
-                            kind: ExprKind::Match(first, ..),
-                            ..
-                        },
-                        ..,
-                        Expr {
-                            kind: ExprKind::Match(last, ..),
-                            ..
-                        },
-                    ],
-                ) => {
-                    let snippet = snippet_with_applicability(
-                        cx,
-                        first.span.source_callsite().to(last.span.source_callsite()),
-                        "..",
-                        &mut applicability,
-                    );
-                    (macro_call.span, format!("({snippet})"))
-                },
-                _ => return,
-            };
-
             self.prev_ctxt = cur_syntax_ctxt;
 
-            span_lint_and_sugg(
+            span_lint_and_then(
                 cx,
                 DBG_MACRO,
-                sugg_span,
+                macro_call.span,
                 "the `dbg!` macro is intended as a debugging tool",
-                "remove the invocation before committing it to a version control system",
-                suggestion,
-                applicability,
+                |diag| {
+                    let mut applicability = Applicability::MachineApplicable;
+
+                    let (sugg_span, suggestion) = match expr.peel_drop_temps().kind {
+                        // dbg!()
+                        ExprKind::Block(..) => {
+                            // If the `dbg!` macro is a "free" statement and not contained within other expressions,
+                            // remove the whole statement.
+                            if let Node::Stmt(_) = cx.tcx.parent_hir_node(expr.hir_id)
+                                && let Some(semi_span) = cx.sess().source_map().mac_call_stmt_semi_span(macro_call.span)
+                            {
+                                (macro_call.span.to(semi_span), String::new())
+                            } else {
+                                (macro_call.span, String::from("()"))
+                            }
+                        },
+                        // dbg!(1)
+                        ExprKind::Match(val, ..) => (
+                            macro_call.span,
+                            snippet_with_applicability(cx, val.span.source_callsite(), "..", &mut applicability)
+                                .to_string(),
+                        ),
+                        // dbg!(2, 3)
+                        ExprKind::Tup(
+                            [
+                                Expr {
+                                    kind: ExprKind::Match(first, ..),
+                                    ..
+                                },
+                                ..,
+                                Expr {
+                                    kind: ExprKind::Match(last, ..),
+                                    ..
+                                },
+                            ],
+                        ) => {
+                            let snippet = snippet_with_applicability(
+                                cx,
+                                first.span.source_callsite().to(last.span.source_callsite()),
+                                "..",
+                                &mut applicability,
+                            );
+                            (macro_call.span, format!("({snippet})"))
+                        },
+                        _ => unreachable!(),
+                    };
+
+                    diag.span_suggestion(
+                        sugg_span,
+                        "remove the invocation before committing it to a version control system",
+                        suggestion,
+                        applicability,
+                    );
+                },
             );
         }
     }

clippy_lints/src/default_numeric_fallback.rs

@@ -92,27 +92,26 @@ impl<'a, 'tcx> NumericFallbackVisitor<'a, 'tcx> {
             let (suffix, is_float) = match lit_ty.kind() {
                 ty::Int(IntTy::I32) => ("i32", false),
                 ty::Float(FloatTy::F64) => ("f64", true),
-                // Default numeric fallback never results in other types.
                 _ => return,
             };
-
-            let src = if let Some(src) = snippet_opt(self.cx, lit.span) {
-                src
-            } else {
-                match lit.node {
-                    LitKind::Int(src, _) => format!("{src}"),
-                    LitKind::Float(src, _) => format!("{src}"),
-                    _ => return,
-                }
-            };
-            let sugg = numeric_literal::format(&src, Some(suffix), is_float);
             span_lint_hir_and_then(
                 self.cx,
                 DEFAULT_NUMERIC_FALLBACK,
                 emit_hir_id,
                 lit.span,
                 "default numeric fallback might occur",
                 |diag| {
+                    let src = if let Some(src) = snippet_opt(self.cx, lit.span) {
+                        src
+                    } else {
+                        match lit.node {
+                            LitKind::Int(src, _) => format!("{src}"),
+                            LitKind::Float(src, _) => format!("{src}"),
+                            _ => unreachable!("Default numeric fallback never results in other types"),
+                        }
+                    };
+
+                    let sugg = numeric_literal::format(&src, Some(suffix), is_float);
                     diag.span_suggestion(lit.span, "consider adding suffix", sugg, Applicability::MaybeIncorrect);
                 },
             );