Issue 4579 - Ignore runtime.lastError caused by wrapper

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 25 matching lines @@
     "tabs.query",
     "tabs.reload",
     "tabs.sendMessage",
     "tabs.update",
     "webNavigation.getAllFrames",
     "webRequest.handlerBehaviorChanged",
     "windows.create",
     "windows.update"
   ];
 
-  // Errors that occur only when we show an interest in the response from an
-  // API call.
-  const noFulfillmentErrors = new Set([
-    "The message port closed before a response was received.",
+  // Since we add a callback for all messaging API calls in our wrappers,
+  // Chrome assumes we're interested in the response; when there's no response,
+  // it sets runtime.lastError
+  const portClosedBeforeResponseError =
     // Older versions of Chrome have a typo:
     // https://crrev.com/c33f51726eacdcc1a487b21a13611f7eab580d6d
-    "The message port closed before a reponse was received."
-  ]);

[Sebastian Noack, 2017/10/20 01:26:30]

Perhaps, we can just use a regexp to account for this typo? Also, do you happen
to know which Chrome versions had that typo? So that we can document these
versions here, and simplify the logic once we drop support for these versions.

[Manish Jethani, 2017/10/20 01:45:32]

Yes, using a regex now.

The commit was on June 30, 2017, this means it was probably fixed in Chrome 60.
I'll just link to the commit so that way when the lowest supported version is
closer to that date we can figure it out.

+    /^The message port closed before a res?ponse was received\.$/;
 
   function wrapAPI(api)
   {
     let object = browser;
     let path = api.split(".");
     let name = path.pop();
 
     for (let node of path)
     {
       object = object[node];
 
       if (!object)
         return;
     }
 
     let func = object[name];
     object[name] = function(...args)
     {
+      let callStack = new Error().stack;
+
       if (typeof args[args.length - 1] == "function")
         return func.apply(object, args);
 
       // If the last argument is undefined, we drop it from the list assuming
       // it stands for the optional callback. We must do this, because we have
       // to replace it with our own callback. If we simply append our own
       // callback to the list, it won't match the signature of the function and
       // will cause an exception.
       if (typeof args[args.length - 1] == "undefined")
         args.pop();
 
       return new Promise((resolve, reject) =>
       {
         func.call(object, ...args, result =>
         {
           let error = browser.runtime.lastError;
-          if (error && !noFulfillmentErrors.has(error.message))
+          if (error && !portClosedBeforeResponseError.test(error.message))
+          {
+            // runtime.lastError is already an Error instance on Edge, while on
+            // Chrome it is a plain object with only a message property.
+            if (!(error instanceof Error))
+            {
+              error = new Error(error.message);
+
+              // Add a more helpful stack trace.
+              error.stack = callStack;
+            }
+
             reject(error);
+          }
           else
+          {
             resolve(result);
+          }
         });
       });
     };
   }
 
   function shouldWrapAPIs()
   {
     try
     {
       return !(browser.storage.local.get([]) instanceof Promise);
@@ skipping 19 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];
   }
 }