Issue 6388 - Wrap inherited function properties as well

polyfill.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 60 matching lines @@
       object = object[node];
 
       if (!object)
         return;
     }
 
     let func = object[name];
     if (!func)
       return;
 
-    let descriptor = Object.getOwnPropertyDescriptor(object, name);
+    let descriptor;
+    let objectProto = object;
+    do

[Manish Jethani, 2018/02/15 13:17:51]

By the way I find this nicer too:

    let descriptor;
    for (let proto = object;
         !(descriptor = Object.getOwnPropertyDescriptor(proto, name));
         proto = Object.getPrototypeOf(proto));

So the extra variable stays local to the loop, and also we don't check if proto
is non-null, only descriptor.

+    {
+      descriptor = Object.getOwnPropertyDescriptor(objectProto, name);
+    }
+    while (!descriptor && (objectProto = Object.getPrototypeOf(objectProto)));

[Manish Jethani, 2018/02/15 09:59:24]

I think we should have a separate function called getPropertyDescriptor right
above wrapAsyncAPIs that looks like this:

  function getPropertyDescriptor(object, name)
  {
    return Object.getOwnPropertyDescriptor(object, name) ||
           getPropertyDescriptor(Object.getPrototypeOf(object), name);
  }

This is elegant and will not be a performance issue like recursion normally is
since the prototype chain is not very long.

Note that Object.getPrototypeOf here is guaranteed to return non-null (since we
already checked that the object contains the property), we can avoid that check.

 
     delete descriptor["get"];
     delete descriptor["set"];
 
     descriptor.value = function(...args)
     {
       let callStack = new Error().stack;
 
       if (typeof args[args.length - 1] == "function")
         return func.apply(object, args);
@@ skipping 136 matching lines @@
 
   // Workaround since HTMLCollection, NodeList, StyleSheetList, and CSSRuleList
   // didn't have iterator support before Chrome 51.
   // https://bugs.chromium.org/p/chromium/issues/detail?id=401699
   for (let object of [HTMLCollection, NodeList, StyleSheetList, CSSRuleList])
   {
     if (!(Symbol.iterator in object.prototype))
       object.prototype[Symbol.iterator] = Array.prototype[Symbol.iterator];
   }
 }