doc: add internal functionality details of util.inherits

BridgeAR · refack · commit 760b9d64b062 · 2019-01-10T10:03:54.000-05:00
PR-URL: nodejs#24755 Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com> Reviewed-By: Luigi Pinca <luigipinca@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
diff --git a/doc/api/util.md b/doc/api/util.md
@@ -332,6 +332,8 @@ Inherit the prototype methods from one [constructor][] into another. The
 prototype of `constructor` will be set to a new object created from
 `superConstructor`.
 
+This mainly adds some input validation on top of
+`Object.setPrototypeOf(constructor.prototype, superConstructor.prototype)`.
 As an additional convenience, `superConstructor` will be accessible
 through the `constructor.super_` property.
 
