diff --git a/lib/internal/url.js b/lib/internal/url.js
index 5855a47ea470b1..b874aceb1413a8 100644
--- a/lib/internal/url.js
+++ b/lib/internal/url.js
@@ -5,6 +5,7 @@ const {
   hexTable,
   isHexTable
 } = require('internal/querystring');
+const { getConstructorOf } = require('internal/util');
 const binding = process.binding('url');
 const context = Symbol('context');
 const cannotBeBase = Symbol('cannot-be-base');
@@ -184,17 +185,6 @@ function onParseHashComplete(flags, protocol, username, password,
   }
 }
 
-function getEligibleConstructor(obj) {
-  while (obj !== null) {
-    if (Object.prototype.hasOwnProperty.call(obj, 'constructor') &&
-        typeof obj.constructor === 'function') {
-      return obj.constructor;
-    }
-    obj = Object.getPrototypeOf(obj);
-  }
-  return null;
-}
-
 class URL {
   constructor(input, base) {
     // toUSVString is not needed.
@@ -225,7 +215,7 @@ class URL {
     if (typeof depth === 'number' && depth < 0)
       return opts.stylize('[Object]', 'special');
 
-    const ctor = getEligibleConstructor(this);
+    const ctor = getConstructorOf(this);
 
     const obj = Object.create({
       constructor: ctor === null ? URL : ctor
diff --git a/lib/internal/util.js b/lib/internal/util.js
index 0a5d4d1f18dac9..60b15b74797bda 100644
--- a/lib/internal/util.js
+++ b/lib/internal/util.js
@@ -187,3 +187,18 @@ exports.convertToValidSignal = function convertToValidSignal(signal) {
 
   throw new Error('Unknown signal: ' + signal);
 };
+
+exports.getConstructorOf = function getConstructorOf(obj) {
+  while (obj) {
+    var descriptor = Object.getOwnPropertyDescriptor(obj, 'constructor');
+    if (descriptor !== undefined &&
+        typeof descriptor.value === 'function' &&
+        descriptor.value.name !== '') {
+      return descriptor.value;
+    }
+
+    obj = Object.getPrototypeOf(obj);
+  }
+
+  return null;
+};
diff --git a/lib/util.js b/lib/util.js
index 2631f0a2c3e1a1..ddf43a760c2cc9 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -278,22 +278,6 @@ function arrayToHash(array) {
 }
 
 
-function getConstructorOf(obj) {
-  while (obj) {
-    var descriptor = Object.getOwnPropertyDescriptor(obj, 'constructor');
-    if (descriptor !== undefined &&
-        typeof descriptor.value === 'function' &&
-        descriptor.value.name !== '') {
-      return descriptor.value;
-    }
-
-    obj = Object.getPrototypeOf(obj);
-  }
-
-  return null;
-}
-
-
 function ensureDebugIsInitialized() {
   if (Debug === undefined) {
     const runInDebugContext = require('vm').runInDebugContext;
@@ -410,7 +394,7 @@ function formatValue(ctx, value, recurseTimes) {
     });
   }
 
-  var constructor = getConstructorOf(value);
+  var constructor = internalUtil.getConstructorOf(value);
 
   // Some type of object without properties can be shortcutted.
   if (keys.length === 0) {