diff --git a/lib/_debugger.js b/lib/_debugger.js
index f8b69bf4805..9275fb5ebf0 100644
--- a/lib/_debugger.js
+++ b/lib/_debugger.js
@@ -768,7 +768,8 @@ function Interface(stdin, stdout, args) {
   // Copy all prototype methods in repl context
   // Setup them as getters if possible
   for (var i in proto) {
-    if (proto.hasOwnProperty(i) && ignored.indexOf(i) === -1) {
+    if (Object.prototype.hasOwnProperty.call(proto, i) &&
+        ignored.indexOf(i) === -1) {
       defineProperty(i, i);
       if (shortcut[i]) defineProperty(shortcut[i], i);
     }