diff -r 000000000000 -r 6474c204b198 addon-sdk/source/test/pagemod-test-helpers.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/addon-sdk/source/test/pagemod-test-helpers.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,90 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const {Cc,Ci} = require("chrome");
+const timer = require("sdk/timers");
+const xulApp = require("sdk/system/xul-app");
+const { Loader } = require("sdk/test/loader");
+const { openTab, getBrowserForTab, closeTab } = require("sdk/tabs/utils");
+
+/**
+ * A helper function that creates a PageMod, then opens the specified URL
+ * and checks the effect of the page mod on 'onload' event via testCallback.
+ */
+exports.testPageMod = function testPageMod(assert, done, testURL, pageModOptions,
+                                           testCallback, timeout) {
+  if (!xulApp.versionInRange(xulApp.platformVersion, "1.9.3a3", "*") &&
+      !xulApp.versionInRange(xulApp.platformVersion, "1.9.2.7", "1.9.2.*")) {
+    assert.pass("Note: not testing PageMod, as it doesn't work on this platform version");
+    return null;
+  }
+
+  var wm = Cc['@mozilla.org/appshell/window-mediator;1']
+           .getService(Ci.nsIWindowMediator);
+  var browserWindow = wm.getMostRecentWindow("navigator:browser");
+  if (!browserWindow) {
+    assert.pass("page-mod tests: could not find the browser window, so " +
+              "will not run. Use -a firefox to run the pagemod tests.")
+    return null;
+  }
+
+  let loader = Loader(module);
+  let pageMod = loader.require("sdk/page-mod");
+
+  var pageMods = [new pageMod.PageMod(opts) for each(opts in pageModOptions)];
+
+  let newTab = openTab(browserWindow, testURL, {
+    inBackground: false
+  });
+  var b = getBrowserForTab(newTab);
+
+  function onPageLoad() {
+    b.removeEventListener("load", onPageLoad, true);
+    // Delay callback execute as page-mod content scripts may be executed on
+    // load event. So page-mod actions may not be already done.
+    // If we delay even more contentScriptWhen:'end', we may want to modify
+    // this code again.
+    timer.setTimeout(testCallback, 0,
+      b.contentWindow.wrappedJSObject, 
+      function () {
+        pageMods.forEach(function(mod) mod.destroy());
+        // XXX leaks reported if we don't close the tab?
+        closeTab(newTab);
+        loader.unload();
+        done();
+      }
+    );
+  }
+  b.addEventListener("load", onPageLoad, true);
+
+  return pageMods;
+}
+
+/**
+ * helper function that creates a PageMod and calls back the appropriate handler
+ * based on the value of document.readyState at the time contentScript is attached
+ */
+exports.handleReadyState = function(url, contentScriptWhen, callbacks) {
+  const { PageMod } = Loader(module).require('sdk/page-mod');
+
+  let pagemod = PageMod({
+    include: url,
+    attachTo: ['existing', 'top'],
+    contentScriptWhen: contentScriptWhen,
+    contentScript: "self.postMessage(document.readyState)",
+    onAttach: worker => {
+      let { tab } = worker;
+      worker.on('message', readyState => {
+        pagemod.destroy();
+        // generate event name from `readyState`, e.g. `"loading"` becomes `onLoading`.
+        let type = 'on' + readyState[0].toUpperCase() + readyState.substr(1);
+
+        if (type in callbacks)
+          callbacks[type](tab); 
+      })
+    }
+  });
+}