Use match ergonomics compatible with editions 2021 and 2024

Author: samueltardieu

clippy_lints/src/checked_conversions.rs

@@ -232,7 +232,7 @@ fn get_types_from_cast<'a>(
     // or `to_type::MAX as from_type`
     let call_from_cast: Option<(&Expr<'_>, &str)> = if let ExprKind::Cast(limit, from_type) = &expr.kind
         // to_type::max_value(), from_type
-        && let TyKind::Path(ref from_type_path) = &from_type.kind
+        && let TyKind::Path(from_type_path) = &from_type.kind
         && let Some(from_sym) = int_ty_to_sym(from_type_path)
     {
         Some((limit, from_sym))
@@ -245,7 +245,7 @@ fn get_types_from_cast<'a>(
         if let ExprKind::Call(from_func, [limit]) = &expr.kind
             // `from_type::from, to_type::max_value()`
             // `from_type::from`
-            && let ExprKind::Path(ref path) = &from_func.kind
+            && let ExprKind::Path(path) = &from_func.kind
             && let Some(from_sym) = get_implementing_type(path, INTS, "from")
         {
             Some((limit, from_sym))

clippy_lints/src/copy_iterator.rs

@@ -37,7 +37,7 @@ declare_lint_pass!(CopyIterator => [COPY_ITERATOR]);
 impl<'tcx> LateLintPass<'tcx> for CopyIterator {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
         if let ItemKind::Impl(Impl {
-            of_trait: Some(ref trait_ref),
+            of_trait: Some(trait_ref),
             ..
         }) = item.kind
             && let ty = cx.tcx.type_of(item.owner_id).instantiate_identity()

clippy_lints/src/derivable_impls.rs

@@ -187,7 +187,7 @@ fn check_enum<'tcx>(cx: &LateContext<'tcx>, item: &'tcx Item<'_>, func_expr: &Ex
 impl<'tcx> LateLintPass<'tcx> for DerivableImpls {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
         if let ItemKind::Impl(Impl {
-            of_trait: Some(ref trait_ref),
+            of_trait: Some(trait_ref),
             items: [child],
             self_ty,
             ..

clippy_lints/src/derive.rs

@@ -202,7 +202,7 @@ declare_lint_pass!(Derive => [
 impl<'tcx> LateLintPass<'tcx> for Derive {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
         if let ItemKind::Impl(Impl {
-            of_trait: Some(ref trait_ref),
+            of_trait: Some(trait_ref),
             ..
         }) = item.kind
         {

clippy_lints/src/disallowed_script_idents.rs

@@ -80,7 +80,7 @@ impl EarlyLintPass for DisallowedScriptIdents {
         let mut symbols: Vec<_> = symbols.iter().collect();
         symbols.sort_unstable_by_key(|k| k.1);
 
-        for (symbol, &span) in &symbols {
+        for &(symbol, &span) in &symbols {
             // Note: `symbol.as_str()` is an expensive operation, thus should not be called
             // more than once for a single symbol.
             let symbol_str = symbol.as_str();

clippy_lints/src/empty_drop.rs

@@ -36,7 +36,7 @@ declare_lint_pass!(EmptyDrop => [EMPTY_DROP]);
 impl LateLintPass<'_> for EmptyDrop {
     fn check_item(&mut self, cx: &LateContext<'_>, item: &Item<'_>) {
         if let ItemKind::Impl(Impl {
-            of_trait: Some(ref trait_ref),
+            of_trait: Some(trait_ref),
             items: [child],
             ..
         }) = item.kind

clippy_lints/src/len_zero.rs

@@ -629,7 +629,7 @@ fn has_is_empty(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
                 .filter_by_name_unhygienic(is_empty)
                 .any(|item| is_is_empty(cx, item))
         }),
-        ty::Alias(ty::Projection, ref proj) => has_is_empty_impl(cx, proj.def_id),
+        ty::Alias(ty::Projection, proj) => has_is_empty_impl(cx, proj.def_id),
         ty::Adt(id, _) => has_is_empty_impl(cx, id.did()),
         ty::Array(..) | ty::Slice(..) | ty::Str => true,
         _ => false,

clippy_lints/src/lifetimes.rs

@@ -425,7 +425,7 @@ impl<'tcx> Visitor<'tcx> for RefVisitor<'_, 'tcx> {
                 self.visit_opaque_ty(opaque);
                 self.lts.truncate(len);
                 self.lts.extend(bounds.iter().filter_map(|bound| match bound {
-                    GenericArg::Lifetime(&l) => Some(l),
+                    &GenericArg::Lifetime(l) => Some(l),
                     _ => None,
                 }));
             },

clippy_lints/src/manual_async_fn.rs

@@ -169,7 +169,7 @@ fn captures_all_lifetimes(inputs: &[Ty<'_>], output_lifetimes: &[LifetimeName])
 }
 
 fn desugared_async_block<'tcx>(cx: &LateContext<'tcx>, block: &'tcx Block<'tcx>) -> Option<&'tcx Body<'tcx>> {
-    if let Some(Expr {
+    if let Some(&Expr {
         kind: ExprKind::Closure(&Closure { kind, body, .. }),
         ..
     }) = block.expr

clippy_lints/src/matches/match_like_matches.rs

@@ -148,7 +148,7 @@ fn find_bool_lit(ex: &ExprKind<'_>) -> Option<bool> {
         }) => Some(*b),
         ExprKind::Block(
             rustc_hir::Block {
-                stmts: &[],
+                stmts: [],
                 expr: Some(exp),
                 ..
             },