Rollup merge of #106410 - clubby789:borrow-mut-self-mut-self-diag, r=compiler-errors

[rust.git] / src / tools / clippy / clippy_lints / src / swap.rs

diff --git a/src/tools/clippy/clippy_lints/src/swap.rs b/src/tools/clippy/clippy_lints/src/swap.rs
index f46c21e126552f1681438ac10ae6399a2776a963..17e9cc5f6b7c7a7d72a5fd73fed5f043c366708d 100644 (file)
--- a/src/tools/clippy/clippy_lints/src/swap.rs
+++ b/src/tools/clippy/clippy_lints/src/swap.rs
@@ -2,7 +2,7 @@
 use clippy_utils::source::snippet_with_applicability;
 use clippy_utils::sugg::Sugg;
 use clippy_utils::ty::is_type_diagnostic_item;
-use clippy_utils::{can_mut_borrow_both, eq_expr_value, std_or_core};
+use clippy_utils::{can_mut_borrow_both, eq_expr_value, in_constant, std_or_core};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir::{BinOpKind, Block, Expr, ExprKind, PatKind, QPath, Stmt, StmtKind};
@@ -16,6 +16,8 @@
     /// ### What it does
     /// Checks for manual swapping.
     ///
+    /// Note that the lint will not be emitted in const blocks, as the suggestion would not be applicable.
+    ///
     /// ### Why is this bad?
     /// The `std::mem::swap` function exposes the intent better
     /// without deinitializing or copying either variable.
@@ -130,7 +132,7 @@ fn generate_swap_warning(cx: &LateContext<'_>, e1: &Expr<'_>, e2: &Expr<'_>, spa
                 applicability,
             );
             if !is_xor_based {
-                diag.note(&format!("or maybe you should use `{sugg}::mem::replace`?"));
+                diag.note(format!("or maybe you should use `{sugg}::mem::replace`?"));
             }
         },
     );
@@ -138,6 +140,10 @@ fn generate_swap_warning(cx: &LateContext<'_>, e1: &Expr<'_>, e2: &Expr<'_>, spa
 
 /// Implementation of the `MANUAL_SWAP` lint.
 fn check_manual_swap(cx: &LateContext<'_>, block: &Block<'_>) {
+    if in_constant(cx, block.hir_id) {
+        return;
+    }
+
     for w in block.stmts.windows(3) {
         if_chain! {
             // let t = foo();
@@ -208,7 +214,7 @@ fn check_suspicious_swap(cx: &LateContext<'_>, block: &Block<'_>) {
                                 Applicability::MaybeIncorrect,
                             );
                             diag.note(
-                                &format!("or maybe you should use `{sugg}::mem::replace`?")
+                                format!("or maybe you should use `{sugg}::mem::replace`?")
                             );
                         }
                     });