Auto merge of #11538 - Jarcho:proc_mac, r=dswij

Fix `is_from_proc_macro` patterns

fixes #11533

changelog: none

12 files changed, 192 insertions, 122 deletions

diff --git a/src/tools/clippy/clippy_lints/src/as_conversions.rs b/src/tools/clippy/clippy_lints/src/as_conversions.rs
index b9dda49ca41..2de205d80ef 100644
--- a/src/tools/clippy/clippy_lints/src/as_conversions.rs
+++ b/src/tools/clippy/clippy_lints/src/as_conversions.rs
@@ -48,11 +48,10 @@ declare_lint_pass!(AsConversions => [AS_CONVERSIONS]);
 
 impl<'tcx> LateLintPass<'tcx> for AsConversions {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &Expr<'tcx>) {
-        if in_external_macro(cx.sess(), expr.span) || is_from_proc_macro(cx, expr) {
-            return;
-        }
-
-        if let ExprKind::Cast(_, _) = expr.kind {
+        if let ExprKind::Cast(_, _) = expr.kind
+            && !in_external_macro(cx.sess(), expr.span)
+            && !is_from_proc_macro(cx, expr)
+        {
             span_lint_and_help(
                 cx,
                 AS_CONVERSIONS,
diff --git a/src/tools/clippy/clippy_lints/src/borrow_deref_ref.rs b/src/tools/clippy/clippy_lints/src/borrow_deref_ref.rs
index 739ce8f67c2..a3826908326 100644
--- a/src/tools/clippy/clippy_lints/src/borrow_deref_ref.rs
+++ b/src/tools/clippy/clippy_lints/src/borrow_deref_ref.rs
@@ -49,69 +49,64 @@ declare_lint_pass!(BorrowDerefRef => [BORROW_DEREF_REF]);
 
 impl<'tcx> LateLintPass<'tcx> for BorrowDerefRef {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &rustc_hir::Expr<'tcx>) {
-        if_chain! {
-            if !e.span.from_expansion();
-            if let ExprKind::AddrOf(_, Mutability::Not, addrof_target) = e.kind;
-            if !addrof_target.span.from_expansion();
-            if let ExprKind::Unary(UnOp::Deref, deref_target) = addrof_target.kind;
-            if !deref_target.span.from_expansion();
-            if !matches!(deref_target.kind, ExprKind::Unary(UnOp::Deref, ..) );
-            let ref_ty = cx.typeck_results().expr_ty(deref_target);
-            if let ty::Ref(_, inner_ty, Mutability::Not) = ref_ty.kind();
-            if !is_from_proc_macro(cx, e);
-            then{
-
-                if let Some(parent_expr) = get_parent_expr(cx, e){
-                    if matches!(parent_expr.kind, ExprKind::Unary(UnOp::Deref, ..)) &&
-                       !is_lint_allowed(cx, DEREF_ADDROF, parent_expr.hir_id) {
-                        return;
-                    }
+        if !e.span.from_expansion()
+            && let ExprKind::AddrOf(_, Mutability::Not, addrof_target) = e.kind
+            && !addrof_target.span.from_expansion()
+            && let ExprKind::Unary(UnOp::Deref, deref_target) = addrof_target.kind
+            && !deref_target.span.from_expansion()
+            && !matches!(deref_target.kind, ExprKind::Unary(UnOp::Deref, ..))
+            && let ref_ty = cx.typeck_results().expr_ty(deref_target)
+            && let ty::Ref(_, inner_ty, Mutability::Not) = ref_ty.kind()
+        {
+            if let Some(parent_expr) = get_parent_expr(cx, e) {
+                if matches!(parent_expr.kind, ExprKind::Unary(UnOp::Deref, ..))
+                    && !is_lint_allowed(cx, DEREF_ADDROF, parent_expr.hir_id)
+                {
+                    return;
+                }
 
-                    // modification to `&mut &*x` is different from `&mut x`
-                    if matches!(deref_target.kind, ExprKind::Path(..)
-                                             | ExprKind::Field(..)
-                                             | ExprKind::Index(..)
-                                             | ExprKind::Unary(UnOp::Deref, ..))
-                     && matches!(parent_expr.kind, ExprKind::AddrOf(_, Mutability::Mut, _)) {
-                       return;
-                    }
+                // modification to `&mut &*x` is different from `&mut x`
+                if matches!(
+                    deref_target.kind,
+                    ExprKind::Path(..) | ExprKind::Field(..) | ExprKind::Index(..) | ExprKind::Unary(UnOp::Deref, ..)
+                ) && matches!(parent_expr.kind, ExprKind::AddrOf(_, Mutability::Mut, _))
+                {
+                    return;
                 }
+            }
+            if is_from_proc_macro(cx, e) {
+                return;
+            }
 
-                span_lint_and_then(
-                    cx,
-                    BORROW_DEREF_REF,
-                    e.span,
-                    "deref on an immutable reference",
-                    |diag| {
-                        diag.span_suggestion(
-                            e.span,
-                            "if you would like to reborrow, try removing `&*`",
-                            snippet_opt(cx, deref_target.span).unwrap(),
-                            Applicability::MachineApplicable
-                        );
+            span_lint_and_then(
+                cx,
+                BORROW_DEREF_REF,
+                e.span,
+                "deref on an immutable reference",
+                |diag| {
+                    diag.span_suggestion(
+                        e.span,
+                        "if you would like to reborrow, try removing `&*`",
+                        snippet_opt(cx, deref_target.span).unwrap(),
+                        Applicability::MachineApplicable,
+                    );
 
-                        // has deref trait -> give 2 help
-                        // doesn't have deref trait -> give 1 help
-                        if let Some(deref_trait_id) = cx.tcx.lang_items().deref_trait(){
-                            if !implements_trait(cx, *inner_ty, deref_trait_id, &[]) {
-                                return;
-                            }
+                    // has deref trait -> give 2 help
+                    // doesn't have deref trait -> give 1 help
+                    if let Some(deref_trait_id) = cx.tcx.lang_items().deref_trait() {
+                        if !implements_trait(cx, *inner_ty, deref_trait_id, &[]) {
+                            return;
                         }
-
-                        diag.span_suggestion(
-                            e.span,
-                            "if you would like to deref, try using `&**`",
-                            format!(
-                                "&**{}",
-                                &snippet_opt(cx, deref_target.span).unwrap(),
-                             ),
-                            Applicability::MaybeIncorrect
-                        );
-
                     }
-                );
 
-            }
+                    diag.span_suggestion(
+                        e.span,
+                        "if you would like to deref, try using `&**`",
+                        format!("&**{}", &snippet_opt(cx, deref_target.span).unwrap()),
+                        Applicability::MaybeIncorrect,
+                    );
+                },
+            );
         }
     }
 }
diff --git a/src/tools/clippy/clippy_lints/src/manual_float_methods.rs b/src/tools/clippy/clippy_lints/src/manual_float_methods.rs
index 0c4101ceb6b..f923e0ac820 100644
--- a/src/tools/clippy/clippy_lints/src/manual_float_methods.rs
+++ b/src/tools/clippy/clippy_lints/src/manual_float_methods.rs
@@ -105,7 +105,6 @@ impl<'tcx> LateLintPass<'tcx> for ManualFloatMethods {
             // case somebody does that for some reason
             && (is_infinity(const_1) && is_neg_infinity(const_2)
                 || is_neg_infinity(const_1) && is_infinity(const_2))
-            && !is_from_proc_macro(cx, expr)
             && let Some(local_snippet) = snippet_opt(cx, first.span)
         {
             let variant = match (kind.node, lhs_kind.node, rhs_kind.node) {
@@ -113,6 +112,9 @@ impl<'tcx> LateLintPass<'tcx> for ManualFloatMethods {
                 (BinOpKind::And, BinOpKind::Ne, BinOpKind::Ne) => Variant::ManualIsFinite,
                 _ => return,
             };
+            if is_from_proc_macro(cx, expr) {
+                return;
+            }
 
             span_lint_and_then(cx, variant.lint(), expr.span, variant.msg(), |diag| {
                 match variant {
diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_lazy_eval.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_lazy_eval.rs
index 4a651396f14..4429f032605 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_lazy_eval.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_lazy_eval.rs
@@ -19,10 +19,6 @@ pub(super) fn check<'tcx>(
     arg: &'tcx hir::Expr<'_>,
     simplify_using: &str,
 ) {
-    if is_from_proc_macro(cx, expr) {
-        return;
-    }
-
     let is_option = is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(recv), sym::Option);
     let is_result = is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(recv), sym::Result);
     let is_bool = cx.typeck_results().expr_ty(recv).is_bool();
@@ -32,7 +28,7 @@ pub(super) fn check<'tcx>(
             let body = cx.tcx.hir().body(body);
             let body_expr = &body.value;
 
-            if usage::BindingUsageFinder::are_params_used(cx, body) {
+            if usage::BindingUsageFinder::are_params_used(cx, body) || is_from_proc_macro(cx, expr) {
                 return;
             }
 
diff --git a/src/tools/clippy/clippy_lints/src/needless_if.rs b/src/tools/clippy/clippy_lints/src/needless_if.rs
index 1ed7ea6b325..23aabc548a5 100644
--- a/src/tools/clippy/clippy_lints/src/needless_if.rs
+++ b/src/tools/clippy/clippy_lints/src/needless_if.rs
@@ -44,7 +44,6 @@ impl LateLintPass<'_> for NeedlessIf {
             && block.stmts.is_empty()
             && block.expr.is_none()
             && !in_external_macro(cx.sess(), expr.span)
-            && !is_from_proc_macro(cx, expr)
             && let Some(then_snippet) = snippet_opt(cx, then.span)
             // Ignore
             // - empty macro expansions
@@ -53,6 +52,7 @@ impl LateLintPass<'_> for NeedlessIf {
             // - #[cfg]'d out code
             && then_snippet.chars().all(|ch| matches!(ch, '{' | '}') || ch.is_ascii_whitespace())
             && let Some(cond_snippet) = snippet_opt(cx, cond.span)
+            && !is_from_proc_macro(cx, expr)
         {
             span_lint_and_sugg(
                 cx,
diff --git a/src/tools/clippy/clippy_lints/src/operators/arithmetic_side_effects.rs b/src/tools/clippy/clippy_lints/src/operators/arithmetic_side_effects.rs
index f7d9650b2f8..4c6462b7747 100644
--- a/src/tools/clippy/clippy_lints/src/operators/arithmetic_side_effects.rs
+++ b/src/tools/clippy/clippy_lints/src/operators/arithmetic_side_effects.rs
@@ -132,7 +132,11 @@ impl ArithmeticSideEffects {
     }
 
     // Common entry-point to avoid code duplication.
-    fn issue_lint(&mut self, cx: &LateContext<'_>, expr: &hir::Expr<'_>) {
+    fn issue_lint<'tcx>(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
+        if is_from_proc_macro(cx, expr) {
+            return;
+        }
+
         let msg = "arithmetic operation that can potentially result in unexpected side-effects";
         span_lint(cx, ARITHMETIC_SIDE_EFFECTS, expr.span, msg);
         self.expr_span = Some(expr.span);
@@ -160,10 +164,10 @@ impl ArithmeticSideEffects {
     fn manage_bin_ops<'tcx>(
         &mut self,
         cx: &LateContext<'tcx>,
-        expr: &hir::Expr<'tcx>,
+        expr: &'tcx hir::Expr<'_>,
         op: &Spanned<hir::BinOpKind>,
-        lhs: &hir::Expr<'tcx>,
-        rhs: &hir::Expr<'tcx>,
+        lhs: &'tcx hir::Expr<'_>,
+        rhs: &'tcx hir::Expr<'_>,
     ) {
         if constant_simple(cx, cx.typeck_results(), expr).is_some() {
             return;
@@ -236,10 +240,10 @@ impl ArithmeticSideEffects {
     /// provided input.
     fn manage_method_call<'tcx>(
         &mut self,
-        args: &[hir::Expr<'tcx>],
+        args: &'tcx [hir::Expr<'_>],
         cx: &LateContext<'tcx>,
-        ps: &hir::PathSegment<'tcx>,
-        receiver: &hir::Expr<'tcx>,
+        ps: &'tcx hir::PathSegment<'_>,
+        receiver: &'tcx hir::Expr<'_>,
     ) {
         let Some(arg) = args.first() else {
             return;
@@ -264,8 +268,8 @@ impl ArithmeticSideEffects {
     fn manage_unary_ops<'tcx>(
         &mut self,
         cx: &LateContext<'tcx>,
-        expr: &hir::Expr<'tcx>,
-        un_expr: &hir::Expr<'tcx>,
+        expr: &'tcx hir::Expr<'_>,
+        un_expr: &'tcx hir::Expr<'_>,
         un_op: hir::UnOp,
     ) {
         let hir::UnOp::Neg = un_op else {
@@ -287,14 +291,13 @@ impl ArithmeticSideEffects {
 
     fn should_skip_expr<'tcx>(&mut self, cx: &LateContext<'tcx>, expr: &hir::Expr<'tcx>) -> bool {
         is_lint_allowed(cx, ARITHMETIC_SIDE_EFFECTS, expr.hir_id)
-            || is_from_proc_macro(cx, expr)
             || self.expr_span.is_some()
             || self.const_span.map_or(false, |sp| sp.contains(expr.span))
     }
 }
 
 impl<'tcx> LateLintPass<'tcx> for ArithmeticSideEffects {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &hir::Expr<'tcx>) {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'tcx>) {
         if self.should_skip_expr(cx, expr) {
             return;
         }
diff --git a/src/tools/clippy/clippy_lints/src/single_call_fn.rs b/src/tools/clippy/clippy_lints/src/single_call_fn.rs
index ae81e1198af..0492df68dad 100644
--- a/src/tools/clippy/clippy_lints/src/single_call_fn.rs
+++ b/src/tools/clippy/clippy_lints/src/single_call_fn.rs
@@ -72,8 +72,8 @@ impl<'tcx> LateLintPass<'tcx> for SingleCallFn {
     ) {
         if self.avoid_breaking_exported_api && cx.effective_visibilities.is_exported(def_id)
             || in_external_macro(cx.sess(), span)
-            || is_from_proc_macro(cx, &(&kind, body, cx.tcx.local_def_id_to_hir_id(def_id), span))
             || is_in_test_function(cx.tcx, body.value.hir_id)
+            || is_from_proc_macro(cx, &(&kind, body, cx.tcx.local_def_id_to_hir_id(def_id), span))
         {
             return;
         }
diff --git a/src/tools/clippy/clippy_utils/src/check_proc_macro.rs b/src/tools/clippy/clippy_utils/src/check_proc_macro.rs
index 3bac0626f88..2f619a306fe 100644
--- a/src/tools/clippy/clippy_utils/src/check_proc_macro.rs
+++ b/src/tools/clippy/clippy_utils/src/check_proc_macro.rs
@@ -12,14 +12,14 @@
 //! code was written, and check if the span contains that text. Note this will only work correctly
 //! if the span is not from a `macro_rules` based macro.
 
-use rustc_ast::ast::{AttrKind, Attribute, IntTy, LitIntType, LitKind, StrStyle, UintTy};
+use rustc_ast::ast::{AttrKind, Attribute, IntTy, LitIntType, LitKind, StrStyle, TraitObjectSyntax, UintTy};
 use rustc_ast::token::CommentKind;
 use rustc_ast::AttrStyle;
 use rustc_hir::intravisit::FnKind;
 use rustc_hir::{
-    Block, BlockCheckMode, Body, Closure, Destination, Expr, ExprKind, FieldDef, FnHeader, HirId, Impl, ImplItem,
-    ImplItemKind, IsAuto, Item, ItemKind, LoopSource, MatchSource, MutTy, Node, QPath, TraitItem, TraitItemKind, Ty,
-    TyKind, UnOp, UnsafeSource, Unsafety, Variant, VariantData, YieldSource,
+    Block, BlockCheckMode, Body, Closure, Destination, Expr, ExprKind, FieldDef, FnHeader, FnRetTy, HirId, Impl,
+    ImplItem, ImplItemKind, IsAuto, Item, ItemKind, LoopSource, MatchSource, MutTy, Node, QPath, TraitItem,
+    TraitItemKind, Ty, TyKind, UnOp, UnsafeSource, Unsafety, Variant, VariantData, YieldSource,
 };
 use rustc_lint::{LateContext, LintContext};
 use rustc_middle::ty::TyCtxt;
@@ -33,8 +33,6 @@ use rustc_target::spec::abi::Abi;
 pub enum Pat {
     /// A single string.
     Str(&'static str),
-    /// A single string.
-    OwnedStr(String),
     /// Any of the given strings.
     MultiStr(&'static [&'static str]),
     /// Any of the given strings.
@@ -59,14 +57,12 @@ fn span_matches_pat(sess: &Session, span: Span, start_pat: Pat, end_pat: Pat) ->
         let end_str = s.trim_end_matches(|c: char| c.is_whitespace() || c == ')' || c == ',');
         (match start_pat {
             Pat::Str(text) => start_str.starts_with(text),
-            Pat::OwnedStr(text) => start_str.starts_with(&text),
             Pat::MultiStr(texts) => texts.iter().any(|s| start_str.starts_with(s)),
             Pat::OwnedMultiStr(texts) => texts.iter().any(|s| start_str.starts_with(s)),
             Pat::Sym(sym) => start_str.starts_with(sym.as_str()),
             Pat::Num => start_str.as_bytes().first().map_or(false, u8::is_ascii_digit),
         } && match end_pat {
             Pat::Str(text) => end_str.ends_with(text),
-            Pat::OwnedStr(text) => end_str.starts_with(&text),
             Pat::MultiStr(texts) => texts.iter().any(|s| start_str.ends_with(s)),
             Pat::OwnedMultiStr(texts) => texts.iter().any(|s| start_str.starts_with(s)),
             Pat::Sym(sym) => end_str.ends_with(sym.as_str()),
@@ -125,6 +121,8 @@ fn qpath_search_pat(path: &QPath<'_>) -> (Pat, Pat) {
 fn expr_search_pat(tcx: TyCtxt<'_>, e: &Expr<'_>) -> (Pat, Pat) {
     match e.kind {
         ExprKind::ConstBlock(_) => (Pat::Str("const"), Pat::Str("}")),
+        // Parenthesis are trimmed from the text before the search patterns are matched.
+        // See: `span_matches_pat`
         ExprKind::Tup([]) => (Pat::Str(")"), Pat::Str("(")),
         ExprKind::Unary(UnOp::Deref, e) => (Pat::Str("*"), expr_search_pat(tcx, e).1),
         ExprKind::Unary(UnOp::Not, e) => (Pat::Str("!"), expr_search_pat(tcx, e).1),
@@ -286,23 +284,17 @@ fn fn_kind_pat(tcx: TyCtxt<'_>, kind: &FnKind<'_>, body: &Body<'_>, hir_id: HirI
 fn attr_search_pat(attr: &Attribute) -> (Pat, Pat) {
     match attr.kind {
         AttrKind::Normal(..) => {
-            let mut pat = if matches!(attr.style, AttrStyle::Outer) {
-                (Pat::Str("#["), Pat::Str("]"))
-            } else {
-                (Pat::Str("#!["), Pat::Str("]"))
-            };
-
-            if let Some(ident) = attr.ident()
-                && let Pat::Str(old_pat) = pat.0
-            {
+            if let Some(ident) = attr.ident() {
                 // TODO: I feel like it's likely we can use `Cow` instead but this will require quite a bit of
                 // refactoring
                 // NOTE: This will likely have false positives, like `allow = 1`
-                pat.0 = Pat::OwnedMultiStr(vec![ident.to_string(), old_pat.to_owned()]);
-                pat.1 = Pat::Str("");
+                (
+                    Pat::OwnedMultiStr(vec![ident.to_string(), "#".to_owned()]),
+                    Pat::Str(""),
+                )
+            } else {
+                (Pat::Str("#"), Pat::Str("]"))
             }
-
-            pat
         },
         AttrKind::DocComment(_kind @ CommentKind::Line, ..) => {
             if matches!(attr.style, AttrStyle::Outer) {
@@ -324,32 +316,42 @@ fn attr_search_pat(attr: &Attribute) -> (Pat, Pat) {
 fn ty_search_pat(ty: &Ty<'_>) -> (Pat, Pat) {
     match ty.kind {
         TyKind::Slice(..) | TyKind::Array(..) => (Pat::Str("["), Pat::Str("]")),
-        TyKind::Ptr(MutTy { mutbl, ty }) => (
-            if mutbl.is_mut() {
-                Pat::Str("*const")
-            } else {
-                Pat::Str("*mut")
-            },
-            ty_search_pat(ty).1,
-        ),
+        TyKind::Ptr(MutTy { ty, .. }) => (Pat::Str("*"), ty_search_pat(ty).1),
         TyKind::Ref(_, MutTy { ty, .. }) => (Pat::Str("&"), ty_search_pat(ty).1),
         TyKind::BareFn(bare_fn) => (
-            Pat::OwnedStr(format!("{}{} fn", bare_fn.unsafety.prefix_str(), bare_fn.abi.name())),
-            ty_search_pat(ty).1,
+            if bare_fn.unsafety == Unsafety::Unsafe {
+                Pat::Str("unsafe")
+            } else if bare_fn.abi != Abi::Rust {
+                Pat::Str("extern")
+            } else {
+                Pat::MultiStr(&["fn", "extern"])
+            },
+            match bare_fn.decl.output {
+                FnRetTy::DefaultReturn(_) => {
+                    if let [.., ty] = bare_fn.decl.inputs {
+                        ty_search_pat(ty).1
+                    } else {
+                        Pat::Str("(")
+                    }
+                },
+                FnRetTy::Return(ty) => ty_search_pat(ty).1,
+            },
         ),
-        TyKind::Never => (Pat::Str("!"), Pat::Str("")),
-        TyKind::Tup(..) => (Pat::Str("("), Pat::Str(")")),
+        TyKind::Never => (Pat::Str("!"), Pat::Str("!")),
+        // Parenthesis are trimmed from the text before the search patterns are matched.
+        // See: `span_matches_pat`
+        TyKind::Tup([]) => (Pat::Str(")"), Pat::Str("(")),
+        TyKind::Tup([ty]) => ty_search_pat(ty),
+        TyKind::Tup([head, .., tail]) => (ty_search_pat(head).0, ty_search_pat(tail).1),
         TyKind::OpaqueDef(..) => (Pat::Str("impl"), Pat::Str("")),
         TyKind::Path(qpath) => qpath_search_pat(&qpath),
-        // NOTE: This is missing `TraitObject`. It will always return true then.
+        TyKind::Infer => (Pat::Str("_"), Pat::Str("_")),
+        TyKind::TraitObject(_, _, TraitObjectSyntax::Dyn) => (Pat::Str("dyn"), Pat::Str("")),
+        // NOTE: `TraitObject` is incomplete. It will always return true then.
         _ => (Pat::Str(""), Pat::Str("")),
     }
 }
 
-fn ident_search_pat(ident: Ident) -> (Pat, Pat) {
-    (Pat::OwnedStr(ident.name.as_str().to_owned()), Pat::Str(""))
-}
-
 pub trait WithSearchPat<'cx> {
     type Context: LintContext;
     fn search_pat(&self, cx: &Self::Context) -> (Pat, Pat);
@@ -408,7 +410,7 @@ impl<'cx> WithSearchPat<'cx> for Ident {
     type Context = LateContext<'cx>;
 
     fn search_pat(&self, _cx: &Self::Context) -> (Pat, Pat) {
-        ident_search_pat(*self)
+        (Pat::Sym(self.name), Pat::Sym(self.name))
     }
 
     fn span(&self) -> Span {
diff --git a/src/tools/clippy/tests/ui/doc_unsafe.rs b/src/tools/clippy/tests/ui/doc_unsafe.rs
index 0c8eac5ccff..f7f41c915e3 100644
--- a/src/tools/clippy/tests/ui/doc_unsafe.rs
+++ b/src/tools/clippy/tests/ui/doc_unsafe.rs
@@ -1,6 +1,6 @@
 //@aux-build:proc_macros.rs
 
-#![allow(clippy::let_unit_value)]
+#![allow(clippy::let_unit_value, clippy::needless_pass_by_ref_mut)]
 
 extern crate proc_macros;
 use proc_macros::external;
diff --git a/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.rs b/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.rs
index ea5e74c4c00..bdb6d40d9f6 100644
--- a/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.rs
+++ b/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.rs
@@ -302,6 +302,19 @@ fn filter_copy<T: Copy>(predicate: &mut impl FnMut(T) -> bool) -> impl FnMut(&T)
     move |&item| predicate(item)
 }
 
+// `is_from_proc_macro` stress tests
+fn _empty_tup(x: &mut (())) {}
+fn _single_tup(x: &mut ((i32,))) {}
+fn _multi_tup(x: &mut ((i32, u32))) {}
+fn _fn(x: &mut (fn())) {}
+#[rustfmt::skip]
+fn _extern_rust_fn(x: &mut extern "Rust" fn()) {}
+fn _extern_c_fn(x: &mut extern "C" fn()) {}
+fn _unsafe_fn(x: &mut unsafe fn()) {}
+fn _unsafe_extern_fn(x: &mut unsafe extern "C" fn()) {}
+fn _fn_with_arg(x: &mut unsafe extern "C" fn(i32)) {}
+fn _fn_with_ret(x: &mut unsafe extern "C" fn() -> (i32)) {}
+
 fn main() {
     let mut u = 0;
     let mut v = vec![0];
diff --git a/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.stderr b/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.stderr
index aa937c3f6af..3e1415be08f 100644
--- a/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.stderr
+++ b/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.stderr
@@ -139,5 +139,65 @@ LL | pub async fn closure4(n: &mut usize) {
    |
    = warning: changing this function will impact semver compatibility
 
-error: aborting due to 21 previous errors
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:306:18
+   |
+LL | fn _empty_tup(x: &mut (())) {}
+   |                  ^^^^^^^^^ help: consider changing to: `&()`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:307:19
+   |
+LL | fn _single_tup(x: &mut ((i32,))) {}
+   |                   ^^^^^^^^^^^^^ help: consider changing to: `&(i32,)`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:308:18
+   |
+LL | fn _multi_tup(x: &mut ((i32, u32))) {}
+   |                  ^^^^^^^^^^^^^^^^^ help: consider changing to: `&(i32, u32)`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:309:11
+   |
+LL | fn _fn(x: &mut (fn())) {}
+   |           ^^^^^^^^^^^ help: consider changing to: `&fn()`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:311:23
+   |
+LL | fn _extern_rust_fn(x: &mut extern "Rust" fn()) {}
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^ help: consider changing to: `&extern "Rust" fn()`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:312:20
+   |
+LL | fn _extern_c_fn(x: &mut extern "C" fn()) {}
+   |                    ^^^^^^^^^^^^^^^^^^^^ help: consider changing to: `&extern "C" fn()`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:313:18
+   |
+LL | fn _unsafe_fn(x: &mut unsafe fn()) {}
+   |                  ^^^^^^^^^^^^^^^^ help: consider changing to: `&unsafe fn()`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:314:25
+   |
+LL | fn _unsafe_extern_fn(x: &mut unsafe extern "C" fn()) {}
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider changing to: `&unsafe extern "C" fn()`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:315:20
+   |
+LL | fn _fn_with_arg(x: &mut unsafe extern "C" fn(i32)) {}
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider changing to: `&unsafe extern "C" fn(i32)`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/needless_pass_by_ref_mut.rs:316:20
+   |
+LL | fn _fn_with_ret(x: &mut unsafe extern "C" fn() -> (i32)) {}
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider changing to: `&unsafe extern "C" fn() -> (i32)`
+
+error: aborting due to 31 previous errors
 
diff --git a/src/tools/clippy/tests/ui/unnecessary_unsafety_doc.rs b/src/tools/clippy/tests/ui/unnecessary_unsafety_doc.rs
index 373b18470f6..5ad117eb8db 100644
--- a/src/tools/clippy/tests/ui/unnecessary_unsafety_doc.rs
+++ b/src/tools/clippy/tests/ui/unnecessary_unsafety_doc.rs
@@ -1,6 +1,6 @@
 //@aux-build:proc_macros.rs
 
-#![allow(clippy::let_unit_value)]
+#![allow(clippy::let_unit_value, clippy::needless_pass_by_ref_mut)]
 #![warn(clippy::unnecessary_safety_doc)]
 
 extern crate proc_macros;