From e6570d67085125509347bbc3a5adfc2dae1462ba Mon Sep 17 00:00:00 2001
From: Kris Maglione <maglione.k@gmail.com>
Date: Sun, 6 Nov 2016 18:08:46 -0800
Subject: [PATCH] Bug 1303798: Correctly propagate addListener errors from
 WebRequest.jsm to extension. r=mixedpuppy

MozReview-Commit-ID: BTTNaaAdBs5

--HG--
extra : rebase_source : 585e886fd44d689fea68e49b92e6bb1d29868924
---
 toolkit/components/extensions/ExtensionUtils.jsm | 15 +++++++++++++--
 .../mochitest/test_ext_webrequest_upload.html    | 16 ++++++++++++----
 toolkit/modules/addons/WebRequest.jsm            |  6 +++++-
 3 files changed, 30 insertions(+), 7 deletions(-)

diff --git a/toolkit/components/extensions/ExtensionUtils.jsm b/toolkit/components/extensions/ExtensionUtils.jsm
index ff377cb16435..4f1b7e229ac4 100644
--- a/toolkit/components/extensions/ExtensionUtils.jsm
+++ b/toolkit/components/extensions/ExtensionUtils.jsm
@@ -50,6 +50,12 @@ function getConsole() {
 
 XPCOMUtils.defineLazyGetter(this, "console", getConsole);
 
+/**
+ * An Error subclass for which complete error messages are always passed
+ * to extensions, rather than being interpreted as an unknown error.
+ */
+class ExtensionError extends Error {}
+
 function filterStack(error) {
   return String(error.stack).replace(/(^.*(Task\.jsm|Promise-backend\.js).*\n)+/gm, "<Promise Chain>\n");
 }
@@ -368,7 +374,7 @@ class BaseContext {
       return error;
     }
     let message;
-    if (instanceOf(error, "Object")) {
+    if (instanceOf(error, "Object") || error instanceof ExtensionError) {
       message = error.message;
     } else if (typeof error == "object" &&
         this.principal.subsumes(Cu.getObjectPrincipal(error))) {
@@ -1748,7 +1754,11 @@ class LocalAPIImplementation extends SchemaAPIInterface {
   }
 
   addListener(listener, args) {
-    this.pathObj[this.name].addListener.call(null, listener, ...args);
+    try {
+      this.pathObj[this.name].addListener.call(null, listener, ...args);
+    } catch (e) {
+      throw this.context.normalizeError(e);
+    }
   }
 
   hasListener(listener) {
@@ -2236,6 +2246,7 @@ this.ExtensionUtils = {
   DefaultWeakMap,
   EventEmitter,
   EventManager,
+  ExtensionError,
   IconDetails,
   LocalAPIImplementation,
   LocaleData,
diff --git a/toolkit/components/extensions/test/mochitest/test_ext_webrequest_upload.html b/toolkit/components/extensions/test/mochitest/test_ext_webrequest_upload.html
index 669f1cb6819a..045a4fd8b9ff 100644
--- a/toolkit/components/extensions/test/mochitest/test_ext_webrequest_upload.html
+++ b/toolkit/components/extensions/test/mochitest/test_ext_webrequest_upload.html
@@ -72,10 +72,12 @@ function background() {
     "onCompleted":      [{urls: ["<all_urls>"]}, ["responseHeaders"]],
   };
 
+  let requestBodySupported = true;
+
   function onUpload(details) {
     let url = new URL(details.url);
     let upload = url.searchParams.get("upload");
-    if (!upload) {
+    if (!upload || !requestBodySupported) {
       return;
     }
     let requestBody = details.requestBody;
@@ -113,12 +115,18 @@ function background() {
       browser.webRequest[name].addListener(
         listener.bind(null, name), ...args);
     } catch (e) {
+      browser.test.assertTrue(/\brequestBody\b/.test(e.message),
+                              "Request body is unsupported");
+
       // requestBody is disabled in release builds
       if (!/\brequestBody\b/.test(e.message)) {
-        args.pop();
-        browser.webRequest[name].addListener(
-          listener.bind(null, name), ...args);
+        throw e;
       }
+
+      requestBodySupported = false;
+      args.pop();
+      browser.webRequest[name].addListener(
+        listener.bind(null, name), ...args);
     }
   }
 }
diff --git a/toolkit/modules/addons/WebRequest.jsm b/toolkit/modules/addons/WebRequest.jsm
index 89deefbae8c0..f2afdb3d542c 100644
--- a/toolkit/modules/addons/WebRequest.jsm
+++ b/toolkit/modules/addons/WebRequest.jsm
@@ -22,11 +22,15 @@ XPCOMUtils.defineLazyModuleGetter(this, "AppConstants",
                                   "resource://gre/modules/AppConstants.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "BrowserUtils",
                                   "resource://gre/modules/BrowserUtils.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "ExtensionUtils",
+                                  "resource://gre/modules/ExtensionUtils.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "WebRequestCommon",
                                   "resource://gre/modules/WebRequestCommon.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "WebRequestUpload",
                                   "resource://gre/modules/WebRequestUpload.jsm");
 
+XPCOMUtils.defineLazyGetter(this, "ExtensionError", () => ExtensionUtils.ExtensionError);
+
 function attachToChannel(channel, key, data) {
   if (channel instanceof Ci.nsIWritablePropertyBag2) {
     let wrapper = {wrappedJSObject: data};
@@ -80,7 +84,7 @@ function parseExtra(extra, allowed = []) {
   if (extra) {
     for (let ex of extra) {
       if (allowed.indexOf(ex) == -1) {
-        throw new Error(`Invalid option ${ex}`);
+        throw new ExtensionError(`Invalid option ${ex}`);
       }
     }
   }