diff --git a/js/js.translator/testData/maps.js b/js/js.translator/testData/maps.js
index cc0fa8a6f43..a87f327fd52 100644
--- a/js/js.translator/testData/maps.js
+++ b/js/js.translator/testData/maps.js
@@ -746,7 +746,7 @@
         /** @constructs */
         function () {
             this.$size = 0;
-            this.map = {};
+            this.map = Object.create(null);
         },
         /** @lends {Kotlin.AbstractPrimitiveHashSet.prototype} */
         {
@@ -796,69 +796,18 @@
             }
     });
 
-    var PROTO_NAME = "__proto__";
-
     lazyInitClasses.DefaultPrimitiveHashSet = Kotlin.createClass(
         function () {
             return [Kotlin.AbstractPrimitiveHashSet];
         },
         /** @constructs */
         function () {
-            var superClass = Kotlin.AbstractPrimitiveHashSet;
-
-            superClass.call(this);
-            this.super = superClass.prototype;
-
-            this.containsProto = false;
+            Kotlin.AbstractPrimitiveHashSet.call(this);
         },
         /** @lends {Kotlin.DefaultPrimitiveHashSet.prototype} */
         {
-            contains_za3rmp$: function (key) {
-                var skey = String(key);
-                if (skey === PROTO_NAME) {
-                    return this.containsProto;
-                }
-
-                return this.super.contains_za3rmp$.call(this, key);
-            },
-            add_za3rmp$: function (element) {
-                var skey = String(element);
-                if (skey === PROTO_NAME) {
-                    var isNewElement = !this.containsProto;
-
-                    if (isNewElement) {
-                        this.containsProto = true;
-                        this.$size++;
-                    }
-
-                    return isNewElement;
-                }
-
-                return this.super.add_za3rmp$.call(this, element);
-            },
-            remove_za3rmp$: function (element) {
-                var skey = String(element);
-                if (skey === PROTO_NAME) {
-                    var contains = this.containsProto;
-
-                    if (contains) {
-                        this.containsProto = false;
-                        this.$size++;
-                    }
-
-                    return contains;
-                }
-
-                return this.super.remove_za3rmp$.call(this, element);
-            },
-            clear: function () {
-                this.$size = 0;
-                this.containsProto = false;
-                this.map = {};
-            },
             toArray: function () {
-                var elements = Object.keys(this.map);
-                return !this.containsProto ? elements : elements.concat(PROTO_NAME);
+                return Object.keys(this.map);
             }
     });