get_parent_expr

Author: lengyijun

clippy_lints/src/borrow_deref_ref.rs

@@ -1,8 +1,8 @@
 use crate::reference::DEREF_ADDROF;
 use clippy_utils::diagnostics::span_lint_and_then;
-use clippy_utils::is_lint_allowed;
 use clippy_utils::source::snippet_opt;
 use clippy_utils::ty::implements_trait;
+use clippy_utils::{get_parent_expr, is_lint_allowed};
 use rustc_hir::{ExprKind, UnOp};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::mir::Mutability;
@@ -62,21 +62,19 @@ impl LateLintPass<'_> for BorrowDerefRef {
             if let ty::Ref(_, inner_ty, Mutability::Not) = ref_ty.kind();
             then{
 
-                let map = cx.tcx.hir();
-                if let Some(parent_hir_id) = map.find_parent_node(e.hir_id){
-                    let span = map.span(parent_hir_id);
+                if let Some(parent_expr) = get_parent_expr(cx, e){
+                    let map = cx.tcx.hir();
+                    let span = map.span(parent_expr.hir_id);
                     if span.from_expansion() {
                         return;
                     }
                     if matches!(deref_target.kind, ExprKind::Path(..) | ExprKind::Field(..)) {
-                        if let Some(rustc_hir::Node::Expr(parent_expr)) = map.find(parent_hir_id) {
-                            if matches!(parent_expr.kind, ExprKind::AddrOf(_, Mutability::Mut, _)) {
-                                return;
-                            }
-                            if matches!(parent_expr.kind, ExprKind::Unary(UnOp::Deref, ..)) &&
-                               !is_lint_allowed(cx, DEREF_ADDROF, parent_expr.hir_id) {
-                                return;
-                            }
+                        if matches!(parent_expr.kind, ExprKind::AddrOf(_, Mutability::Mut, _)) {
+                            return;
+                        }
+                        if matches!(parent_expr.kind, ExprKind::Unary(UnOp::Deref, ..)) &&
+                           !is_lint_allowed(cx, DEREF_ADDROF, parent_expr.hir_id) {
+                            return;
                         }
                     }
                 }