From 0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d Mon Sep 17 00:00:00 2001
From: Daniel Baumann <daniel.baumann@progress-linux.org>
Date: Fri, 19 Apr 2024 03:47:29 +0200
Subject: Adding upstream version 115.8.0esr.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
---
 .../mochitest/tests/Harness_sanity/.eslintrc.js    |  12 +
 .../tests/Harness_sanity/ImportTesting.jsm         |   3 +
 .../SpecialPowersLoadChromeScript.js               |  17 +
 testing/mochitest/tests/Harness_sanity/empty.js    |   0
 .../Harness_sanity/file_SpecialPowersFrame1.html   |  14 +
 .../mochitest/tests/Harness_sanity/file_spawn.html |  10 +
 .../Harness_sanity/importtesting_chromescript.js   |   5 +
 .../mochitest/tests/Harness_sanity/mochitest.ini   |  47 ++
 .../Harness_sanity/specialPowers_framescript.js    |  13 +
 .../test_SimpletestGetTestFileURL.html             |  20 +
 .../test_SpecialPowersExtension.html               | 198 ++++++
 .../test_SpecialPowersExtension2.html              |  21 +
 .../test_SpecialPowersLoadChromeScript.html        |  65 ++
 ...est_SpecialPowersLoadChromeScript_function.html |  62 ++
 .../test_SpecialPowersLoadPrivilegedScript.html    |  36 ++
 .../test_SpecialPowersPushPermissions.html         | 232 +++++++
 .../test_SpecialPowersPushPrefEnv.html             | 232 +++++++
 .../Harness_sanity/test_SpecialPowersSandbox.html  | 125 ++++
 .../Harness_sanity/test_SpecialPowersSandbox.js    | 139 +++++
 .../Harness_sanity/test_SpecialPowersSpawn.html    |  69 ++
 .../Harness_sanity/test_SpecialPowersSpawn.js      |  68 ++
 .../test_SpecialPowersSpawnChrome.html             |  32 +
 .../test_TestsRunningAfterSimpleTestFinish.html    |  23 +
 .../tests/Harness_sanity/test_bug649012.html       |  37 ++
 .../tests/Harness_sanity/test_createFiles.html     |  91 +++
 .../tests/Harness_sanity/test_getweakmapkeys.html  |  26 +
 .../Harness_sanity/test_importInMainProcess.html   |  56 ++
 .../tests/Harness_sanity/test_sanity.html          |  62 ++
 .../Harness_sanity/test_sanityEventUtils.html      | 692 +++++++++++++++++++++
 .../tests/Harness_sanity/test_sanityException.html |  16 +
 .../Harness_sanity/test_sanityException2.html      |  22 +
 .../tests/Harness_sanity/test_sanityParams.html    |  13 +
 .../test_sanityRegisteredServiceWorker.html        |  24 +
 .../test_sanityRegisteredServiceWorker2.html       |  25 +
 .../Harness_sanity/test_sanitySimpletest.html      | 103 +++
 .../Harness_sanity/test_sanityWindowSnapshot.html  |  35 ++
 .../tests/Harness_sanity/test_sanity_cleanup.html  |  30 +
 .../tests/Harness_sanity/test_sanity_cleanup2.html |  24 +
 .../tests/Harness_sanity/test_sanity_manifest.html |  16 +
 .../Harness_sanity/test_sanity_manifest_pf.html    |  17 +
 .../test_sanity_waitForCondition.html              |  51 ++
 .../mochitest/tests/Harness_sanity/xpcshell.ini    |   2 +
 42 files changed, 2785 insertions(+)
 create mode 100644 testing/mochitest/tests/Harness_sanity/.eslintrc.js
 create mode 100644 testing/mochitest/tests/Harness_sanity/ImportTesting.jsm
 create mode 100644 testing/mochitest/tests/Harness_sanity/SpecialPowersLoadChromeScript.js
 create mode 100644 testing/mochitest/tests/Harness_sanity/empty.js
 create mode 100644 testing/mochitest/tests/Harness_sanity/file_SpecialPowersFrame1.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/file_spawn.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/importtesting_chromescript.js
 create mode 100644 testing/mochitest/tests/Harness_sanity/mochitest.ini
 create mode 100644 testing/mochitest/tests/Harness_sanity/specialPowers_framescript.js
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SimpletestGetTestFileURL.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersExtension.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersExtension2.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadChromeScript.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadChromeScript_function.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadPrivilegedScript.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersPushPermissions.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersPushPrefEnv.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersSandbox.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersSandbox.js
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.js
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawnChrome.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_TestsRunningAfterSimpleTestFinish.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_bug649012.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_createFiles.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_getweakmapkeys.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_importInMainProcess.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanity.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanityEventUtils.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanityException.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanityException2.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanityParams.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanityRegisteredServiceWorker.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanityRegisteredServiceWorker2.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanitySimpletest.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanityWindowSnapshot.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanity_cleanup.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanity_cleanup2.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanity_manifest.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanity_manifest_pf.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/test_sanity_waitForCondition.html
 create mode 100644 testing/mochitest/tests/Harness_sanity/xpcshell.ini

(limited to 'testing/mochitest/tests/Harness_sanity')

diff --git a/testing/mochitest/tests/Harness_sanity/.eslintrc.js b/testing/mochitest/tests/Harness_sanity/.eslintrc.js
new file mode 100644
index 0000000000..a858d9de4c
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/.eslintrc.js
@@ -0,0 +1,12 @@
+"use strict";
+
+module.exports = {
+  extends: ["plugin:mozilla/xpcshell-test"],
+
+  overrides: [
+    {
+      files: "*.html",
+      env: { browser: true },
+    },
+  ],
+};
diff --git a/testing/mochitest/tests/Harness_sanity/ImportTesting.jsm b/testing/mochitest/tests/Harness_sanity/ImportTesting.jsm
new file mode 100644
index 0000000000..34c9652256
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/ImportTesting.jsm
@@ -0,0 +1,3 @@
+var EXPORTED_SYMBOLS = [];
+
+// Empty module for testing via SpecialPowers.importInMainProcess.
diff --git a/testing/mochitest/tests/Harness_sanity/SpecialPowersLoadChromeScript.js b/testing/mochitest/tests/Harness_sanity/SpecialPowersLoadChromeScript.js
new file mode 100644
index 0000000000..9591f3bca4
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/SpecialPowersLoadChromeScript.js
@@ -0,0 +1,17 @@
+/* eslint-env mozilla/chrome-script */
+
+// Just receive 'foo' message and forward it back
+// as 'bar' message
+addMessageListener("foo", function (message) {
+  sendAsyncMessage("bar", message);
+});
+
+addMessageListener("valid-assert", function (message) {
+  assert.ok(true, "valid assertion");
+  assert.equal(1, 1, "another valid assertion");
+  sendAsyncMessage("valid-assert-done");
+});
+
+addMessageListener("sync-message", () => {
+  return "Received a synchronous message.";
+});
diff --git a/testing/mochitest/tests/Harness_sanity/empty.js b/testing/mochitest/tests/Harness_sanity/empty.js
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/testing/mochitest/tests/Harness_sanity/file_SpecialPowersFrame1.html b/testing/mochitest/tests/Harness_sanity/file_SpecialPowersFrame1.html
new file mode 100644
index 0000000000..f6d7046e9a
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/file_SpecialPowersFrame1.html
@@ -0,0 +1,14 @@
+<html>
+  <head>
+    <script src="/tests/SimpleTest/SimpleTest.js"></script>
+    <script src="/tests/SimpleTest/EventUtils.js"></script>
+    <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+  </head>
+  <body>
+    <div id="content" style="display: none">
+      <script type="text/javascript">
+        is(SpecialPowers.sanityCheck(), "foo", "Check Special Powers in iframe");
+      </script>
+    </div>
+  </body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/file_spawn.html b/testing/mochitest/tests/Harness_sanity/file_spawn.html
new file mode 100644
index 0000000000..b34317b024
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/file_spawn.html
@@ -0,0 +1,10 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title></title>
+</head>
+<body>
+  <span id="span">Hello there.</span>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/importtesting_chromescript.js b/testing/mochitest/tests/Harness_sanity/importtesting_chromescript.js
new file mode 100644
index 0000000000..d89dd8b47d
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/importtesting_chromescript.js
@@ -0,0 +1,5 @@
+/* eslint-env mozilla/chrome-script */
+
+addMessageListener("ImportTesting:IsModuleLoaded", function (msg) {
+  sendAsyncMessage("ImportTesting:IsModuleLoadedReply", Cu.isModuleLoaded(msg));
+});
diff --git a/testing/mochitest/tests/Harness_sanity/mochitest.ini b/testing/mochitest/tests/Harness_sanity/mochitest.ini
new file mode 100644
index 0000000000..710c4ccf64
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/mochitest.ini
@@ -0,0 +1,47 @@
+[DEFAULT]
+[test_TestsRunningAfterSimpleTestFinish.html]
+skip-if = true #depends on fix for bug 1048446
+[test_createFiles.html]
+[test_importInMainProcess.html]
+skip-if = verify
+support-files = importtesting_chromescript.js
+[test_sanity.html]
+[test_sanityException.html]
+[test_sanityException2.html]
+[test_sanityParams.html]
+[test_sanityRegisteredServiceWorker.html]
+support-files = empty.js
+[test_sanityRegisteredServiceWorker2.html]
+skip-if = verify
+support-files = empty.js
+[test_sanityWindowSnapshot.html]
+[test_SpecialPowersExtension.html]
+[test_SpecialPowersExtension2.html]
+support-files = file_SpecialPowersFrame1.html
+[test_SpecialPowersPushPermissions.html]
+support-files =
+    specialPowers_framescript.js
+[test_SpecialPowersPushPrefEnv.html]
+[test_SpecialPowersSandbox.html]
+[test_SpecialPowersSpawn.html]
+support-files = file_spawn.html
+[test_SpecialPowersSpawnChrome.html]
+[test_SimpletestGetTestFileURL.html]
+[test_SpecialPowersLoadChromeScript.html]
+support-files = SpecialPowersLoadChromeScript.js
+[test_SpecialPowersLoadChromeScript_function.html]
+[test_SpecialPowersLoadPrivilegedScript.html]
+[test_bug649012.html]
+[test_sanity_cleanup.html]
+[test_sanity_cleanup2.html]
+[test_sanityEventUtils.html]
+skip-if =
+  verify && (os == 'win')  # bug 688052
+  fission && xorigin  # Bug 1716411 - New fission platform triage
+[test_sanitySimpletest.html]
+[test_sanity_manifest.html]
+fail-if = true
+[test_sanity_manifest_pf.html]
+fail-if = true
+[test_sanity_waitForCondition.html]
+[test_getweakmapkeys.html]
diff --git a/testing/mochitest/tests/Harness_sanity/specialPowers_framescript.js b/testing/mochitest/tests/Harness_sanity/specialPowers_framescript.js
new file mode 100644
index 0000000000..efc017099b
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/specialPowers_framescript.js
@@ -0,0 +1,13 @@
+/* eslint-env mozilla/chrome-script */
+
+var permChangedObs = {
+  observe(subject, topic, data) {
+    if (topic == "perm-changed") {
+      var permission = subject.QueryInterface(Ci.nsIPermission);
+      var msg = { op: data, type: permission.type };
+      sendAsyncMessage("perm-changed", msg);
+    }
+  },
+};
+
+Services.obs.addObserver(permChangedObs, "perm-changed");
diff --git a/testing/mochitest/tests/Harness_sanity/test_SimpletestGetTestFileURL.html b/testing/mochitest/tests/Harness_sanity/test_SimpletestGetTestFileURL.html
new file mode 100644
index 0000000000..ef368c0ab5
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SimpletestGetTestFileURL.html
@@ -0,0 +1,20 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers extension</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+var filename = "MyTestDataFile.txt";
+var url = SimpleTest.getTestFileURL(filename);
+is(url, document.location.href.replace(/test_SimpletestGetTestFileURL\.html.*/, filename));
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersExtension.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersExtension.html
new file mode 100644
index 0000000000..34b75933a0
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersExtension.html
@@ -0,0 +1,198 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers extension</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body onload="starttest();">
+
+<div id="content" style="display: none">
+  <canvas id="testcanvas" width="200" height="200">
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+var eventCount = 0;
+function testEventListener(e) {
+  ++eventCount;
+}
+
+function testEventListener2(e) {
+  ++eventCount;
+}
+
+function dispatchTestEvent() {
+  var e = document.createEvent("Event");
+  e.initEvent("TestEvent", true, true);
+  window.dispatchEvent(e);
+}
+
+dump("\nSPECIALPTEST:::Test script loaded " + (new Date).getTime() + "\n");
+SimpleTest.waitForExplicitFinish();
+var startTime = new Date();
+async function starttest(){
+  dump("\nSPECIALPTEST:::Test script running after load " + (new Date).getTime() + "\n");
+
+  /** Test for SpecialPowers extension **/
+  is(SpecialPowers.sanityCheck(), "foo", "check to see whether the Special Powers extension is installed.");
+
+  // Test a sync call into chrome
+  await SpecialPowers.setBoolPref('extensions.checkCompatibility', true);
+  is(SpecialPowers.getBoolPref('extensions.checkCompatibility'), true, "Check to see if we can set a preference properly");
+  await SpecialPowers.clearUserPref('extensions.checkCompatibility');
+
+  // Test a int pref
+  await SpecialPowers.setIntPref('extensions.foobar', 42);
+  is(SpecialPowers.getIntPref('extensions.foobar'), 42, "Check int pref");
+  await SpecialPowers.clearUserPref('extensions.foobar');
+
+  // Test a string pref
+  await SpecialPowers.setCharPref("extensions.foobaz", "hi there");
+  is(SpecialPowers.getCharPref("extensions.foobaz"), "hi there", "Check string pref");
+  await SpecialPowers.clearUserPref("extensions.foobaz");
+
+  // Test an invalid pref
+  var retVal = null;
+  // eslint-disable-next-line mozilla/use-default-preference-values
+  try {
+    retVal = SpecialPowers.getBoolPref('extensions.checkCompat0123456789');
+  } catch (ex) {
+    retVal = ex;
+  }
+  is(retVal.result, SpecialPowers.Cr.NS_ERROR_UNEXPECTED,
+     "received an exception trying to get an unset preference value");
+
+  SpecialPowers.addChromeEventListener("TestEvent", testEventListener, true, true);
+  SpecialPowers.addChromeEventListener("TestEvent", testEventListener2, true, false);
+  dispatchTestEvent();
+  is(eventCount, 1, "Should have got an event!");
+
+  SpecialPowers.removeChromeEventListener("TestEvent", testEventListener, true);
+  SpecialPowers.removeChromeEventListener("TestEvent", testEventListener2, true);
+  dispatchTestEvent();
+  is(eventCount, 1, "Shouldn't have got an event!");
+
+  // Test Complex Pref - TODO: Without chrome access, I don't know how you'd actually
+  // set this preference since you have to create an XPCOM object.
+  // Leaving untested for now.
+
+  // Test a DOMWindowUtils method and property
+  is(SpecialPowers.DOMWindowUtils.getClassName(window), "Proxy");
+  is(SpecialPowers.DOMWindowUtils.docCharsetIsForced, false);
+
+  // QueryInterface and getPrivilegedProps tests
+  is(SpecialPowers.can_QI(SpecialPowers), false);
+  let doc = SpecialPowers.wrap(document);
+  is(SpecialPowers.getPrivilegedProps(doc, "baseURIObject.fileName"), null,
+     "Should not have a fileName property yet");
+  let uri = SpecialPowers.getPrivilegedProps(doc, "baseURIObject");
+  ok(SpecialPowers.can_QI(uri));
+  ok(SpecialPowers.do_QueryInterface(uri, "nsIURL"));
+  is(SpecialPowers.getPrivilegedProps(doc, "baseURIObject.fileName"),
+     "test_SpecialPowersExtension.html",
+     "Should have a fileName property now");
+
+  //try to run garbage collection
+  SpecialPowers.gc();
+
+  //
+  // Test the SpecialPowers wrapper.
+  //
+
+  let fp = SpecialPowers.Cc["@mozilla.org/filepicker;1"].createInstance(SpecialPowers.Ci.nsIFilePicker);
+  is(fp.mode, SpecialPowers.Ci.nsIFilePicker.modeOpen, "Should be able to get props off privileged objects");
+  var testURI = SpecialPowers.Cc['@mozilla.org/network/standard-url-mutator;1']
+                             .createInstance(SpecialPowers.Ci.nsIURIMutator)
+                             .setSpec("http://www.foobar.org/")
+                             .finalize();
+  is(testURI.spec, "http://www.foobar.org/", "Getters/Setters should work correctly");
+  is(SpecialPowers.wrap(document).getElementsByTagName('details').length, 0, "Should work with proxy-based DOM bindings.");
+
+  // Play with the window object.
+  var docShell = SpecialPowers.wrap(window).docShell;
+  ok(docShell.browsingContext, "Able to pull properties off of docshell!");
+
+  // Make sure Xray-wrapped functions work.
+  try {
+    SpecialPowers.wrap(SpecialPowers.Components).ID('{00000000-0000-0000-0000-000000000000}');
+    ok(true, "Didn't throw");
+  }
+  catch (e) {
+    ok(false, "Threw while trying to call Xray-wrapped function.");
+  }
+
+  // Check constructors.
+  var BinaryInputStream = SpecialPowers.wrap(SpecialPowers.Components).Constructor("@mozilla.org/binaryinputstream;1");
+  var bis = new BinaryInputStream();
+  ok(/nsISupports/.exec(bis.toString()), "Should get the proper object out of the constructor");
+  function TestConstructor() {
+    SpecialPowers.wrap(this).foo = 2;
+  }
+  var WrappedConstructor = SpecialPowers.wrap(TestConstructor);
+  is((new WrappedConstructor()).foo, 2, "JS constructors work properly when wrapped");
+
+  // Try messing around with QuickStubbed getters/setters and make sure the wrapper deals.
+  var ctx = SpecialPowers.wrap(document).getElementById('testcanvas').getContext('2d');
+  var pixels = ctx.getImageData(0,0,1,1);
+  try {
+    pixels.data;
+    ok(true, "Didn't throw getting quickstubbed accessor prop from proto");
+  }
+  catch (e) {
+    ok(false, "Threw while getting quickstubbed accessor prop from proto");
+  }
+
+  // Check functions that return null.
+  var returnsNull = function() { return null; }
+  is(SpecialPowers.wrap(returnsNull)(), null, "Should be able to handle functions that return null.");
+
+  // Check a function that throws.
+  var thrower = function() { throw new Error('hah'); }
+  try {
+    SpecialPowers.wrap(thrower)();
+    ok(false, "Should have thrown");
+  } catch (e) {
+    ok(SpecialPowers.isWrapper(e), "Exceptions should be wrapped for call");
+    is(e.message, 'hah', "Correct message");
+  }
+  try {
+    var ctor = SpecialPowers.wrap(thrower);
+    new ctor();
+    ok(false, "Should have thrown");
+  } catch (e) {
+    ok(SpecialPowers.isWrapper(e), "Exceptions should be wrapped for construct");
+    is(e.message, 'hah', "Correct message");
+  }
+
+  // Play around with a JS object to check the non-xray path.
+  var noxray_proto = {a: 3, b: 12};
+  var noxray = {a: 5, c: 32};
+  noxray.__proto__ = noxray_proto;
+  var noxray_wrapper = SpecialPowers.wrap(noxray);
+  is(noxray_wrapper.c, 32, "Regular properties should work.");
+  is(noxray_wrapper.a, 5, "Shadow properties should work.");
+  is(noxray_wrapper.b, 12, "Proto properties should work.");
+  noxray.b = 122;
+  is(noxray_wrapper.b, 122, "Should be able to shadow.");
+
+  // Try setting file input values via an Xray wrapper.
+  SpecialPowers.wrap(document).title = "foo";
+  is(document.title, "foo", "Set property correctly on Xray-wrapped DOM object");
+  is(SpecialPowers.wrap(document).URI, document.URI, "Got property correctly on Xray-wrapped DOM object");
+
+  info("\nProfile::SpecialPowersRunTime: " + (new Date() - startTime) + "\n");
+
+  // bug 855192
+  ok(SpecialPowers.MockPermissionPrompt, "check mock permission prompt");
+
+  // Set a pref using pushPrefEnv to make sure that flushPrefEnv is
+  // automatically called before we invoke
+  // test_SpecialPowersExtension2.html.
+  SpecialPowers.pushPrefEnv({set: [['testing.some_arbitrary_pref', true]]},
+                            function() { SimpleTest.finish(); });
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersExtension2.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersExtension2.html
new file mode 100644
index 0000000000..1adee718f1
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersExtension2.html
@@ -0,0 +1,21 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers extension</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<div id="content" class="testbody">
+  <script type="text/javascript">
+    dump("\nSPECIALPTEST2:::Loading test2 file now " + (new Date).getTime() + "\n");
+    is(SpecialPowers.sanityCheck(), "foo", "Special Powers top level");
+    ok(!SpecialPowers.Services.prefs.prefHasUserValue('testing.some_arbitrary_pref'),
+       "should not retain pref from previous test");
+  </script>
+  <iframe id="frame1" src="file_SpecialPowersFrame1.html">
+  </iframe>
+</div>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadChromeScript.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadChromeScript.html
new file mode 100644
index 0000000000..7242bd19f5
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadChromeScript.html
@@ -0,0 +1,65 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers.loadChromeScript</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+SimpleTest.waitForExplicitFinish();
+
+var url = SimpleTest.getTestFileURL("SpecialPowersLoadChromeScript.js");
+var script = SpecialPowers.loadChromeScript(url);
+
+var MESSAGE = { bar: true };
+script.addMessageListener("bar", function (message) {
+  is(JSON.stringify(message), JSON.stringify(MESSAGE),
+     "received back message from the chrome script");
+
+  checkAssert();
+});
+
+function checkAssert() {
+  script.sendAsyncMessage("valid-assert");
+  script.addMessageListener("valid-assert-done", endOfFirstTest);
+}
+
+var script2;
+
+function endOfFirstTest() {
+  script.destroy();
+
+  // wantGlobalProperties should add the specified properties to the sandbox
+  // that is used to run the chrome script.
+  script2 = SpecialPowers.loadChromeScript(_ => {
+    /* eslint-env mozilla/chrome-script */
+    addMessageListener("valid-assert", function (message) {
+      assert.equal(typeof XMLHttpRequest, "function", "XMLHttpRequest is defined");
+      assert.equal(typeof CSS, "undefined", "CSS is not defined");
+      sendAsyncMessage("valid-assert-done");
+    });
+  }, { wantGlobalProperties: ["ChromeUtils", "XMLHttpRequest"] });
+
+  script2.sendAsyncMessage("valid-assert");
+  script2.addMessageListener("valid-assert-done", endOfTest);
+
+}
+
+async function endOfTest() {
+  is(await script.sendQuery("sync-message"), "Received a synchronous message.",
+     "Check sync return value");
+
+  script2.destroy();
+  SimpleTest.finish();
+}
+
+script.sendAsyncMessage("foo", MESSAGE);
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadChromeScript_function.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadChromeScript_function.html
new file mode 100644
index 0000000000..af31d7b25a
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadChromeScript_function.html
@@ -0,0 +1,62 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers.loadChromeScript</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+SimpleTest.waitForExplicitFinish();
+
+
+var script = SpecialPowers.loadChromeScript(function loadChromeScriptTest() {
+  /* eslint-env mozilla/chrome-script */
+  // Copied from SpecialPowersLoadChromeScript.js
+
+  // Just receive 'foo' message and forward it back
+  // as 'bar' message
+  addMessageListener("foo", function (message) {
+    sendAsyncMessage("bar", message);
+  });
+
+  addMessageListener("valid-assert", function (message) {
+    assert.ok(true, "valid assertion");
+    assert.equal(1, 1, "another valid assertion");
+    sendAsyncMessage("valid-assert-done");
+  });
+
+  addMessageListener("sync-message", () => {
+    return "Received a synchronous message.";
+  });
+});
+
+var MESSAGE = { bar: true };
+script.addMessageListener("bar", function (message) {
+  is(JSON.stringify(message), JSON.stringify(MESSAGE),
+     "received back message from the chrome script");
+
+  checkAssert();
+});
+
+function checkAssert() {
+  script.sendAsyncMessage("valid-assert");
+  script.addMessageListener("valid-assert-done", endOfTest);
+}
+
+async function endOfTest() {
+  is(await script.sendQuery("sync-message"), "Received a synchronous message.",
+     "Check sync return value");
+
+  script.destroy();
+  SimpleTest.finish();
+}
+
+script.sendAsyncMessage("foo", MESSAGE);
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadPrivilegedScript.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadPrivilegedScript.html
new file mode 100644
index 0000000000..6294c44dfe
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersLoadPrivilegedScript.html
@@ -0,0 +1,36 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers.loadChromeScript</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+SimpleTest.waitForExplicitFinish();
+
+/* eslint-disable mozilla/use-services */
+function loadPrivilegedScriptTest() {
+  function isMainProcess() {
+    return Cc["@mozilla.org/xre/app-info;1"].
+             getService(Ci.nsIXULRuntime).
+             processType == Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT;
+  }
+  port.postMessage({'isMainProcess': isMainProcess()});
+}
+
+var contentProcessType = SpecialPowers.isMainProcess();
+var port;
+try {
+  port = SpecialPowers.loadPrivilegedScript(loadPrivilegedScriptTest.toString());
+} catch (e) {
+  ok(false, "loadPrivilegedScript shoulde not throw");
+}
+port.onmessage = (e) => {
+  is(contentProcessType, e.data.isMainProcess, "content and the script should be in the same process");
+  SimpleTest.finish();
+};
+</script>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersPushPermissions.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersPushPermissions.html
new file mode 100644
index 0000000000..3aeebb22ff
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersPushPermissions.html
@@ -0,0 +1,232 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers extension</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body onload="starttest();">
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+const ALLOW_ACTION = SpecialPowers.Ci.nsIPermissionManager.ALLOW_ACTION;
+const DENY_ACTION = SpecialPowers.Ci.nsIPermissionManager.DENY_ACTION;
+const UNKNOWN_ACTION = SpecialPowers.Ci.nsIPermissionManager.UNKNOWN_ACTION;
+const PROMPT_ACTION = SpecialPowers.Ci.nsIPermissionManager.PROMPT_ACTION;
+const ACCESS_SESSION = SpecialPowers.Ci.nsICookiePermission.ACCESS_SESSION;
+
+const EXPIRE_TIME = SpecialPowers.Ci.nsIPermissionManager.EXPIRE_TIME;
+// expire Setting:
+//     start                 expire time point
+//   ----|------------------------|-----------
+//       <------------------------>
+//                 PERIOD
+var start;
+// PR_Now() that called in PermissionManager to get the system time
+// is sometimes 100ms~600s more than Date.now() on Android 4.3 API11.
+// Thus, the PERIOD should be larger than 600ms in this test.
+const PERIOD = 900;
+var gScript = SpecialPowers.loadChromeScript(SimpleTest.getTestFileURL('specialPowers_framescript.js'));
+SimpleTest.requestFlakyTimeout("untriaged");
+
+function starttest(){
+  SpecialPowers.addPermission("pPROMPT", PROMPT_ACTION, document);
+  SpecialPowers.addPermission("pALLOW", ALLOW_ACTION, document);
+  SpecialPowers.addPermission("pDENY", DENY_ACTION, document);
+  SpecialPowers.addPermission("pREMOVE", ALLOW_ACTION, document);
+  SpecialPowers.addPermission("pSESSION", ACCESS_SESSION, document);
+
+  setTimeout(test1, 0);
+}
+
+SimpleTest.waitForExplicitFinish();
+
+async function test1() {
+  if (!await SpecialPowers.testPermission('pALLOW', ALLOW_ACTION, document)) {
+    dump('/**** allow not set ****/\n');
+    setTimeout(test1, 0);
+  } else if (!await SpecialPowers.testPermission('pDENY', DENY_ACTION, document)) {
+    dump('/**** deny not set ****/\n');
+    setTimeout(test1, 0);
+  } else if (!await SpecialPowers.testPermission('pPROMPT', PROMPT_ACTION, document)) {
+    dump('/**** prompt not set ****/\n');
+    setTimeout(test1, 0);
+  } else if (!await SpecialPowers.testPermission('pREMOVE', ALLOW_ACTION, document)) {
+    dump('/**** remove not set ****/\n');
+    setTimeout(test1, 0);
+  } else if (!await SpecialPowers.testPermission('pSESSION', ACCESS_SESSION, document)) {
+    dump('/**** ACCESS_SESSION not set ****/\n');
+    setTimeout(test1, 0);
+  } else {
+    test2();
+  }
+}
+
+async function test2() {
+  ok(await SpecialPowers.testPermission('pUNKNOWN', UNKNOWN_ACTION, document), 'pUNKNOWN value should have UNKOWN permission');
+  SpecialPowers.pushPermissions([
+    {'type': 'pUNKNOWN', 'allow': true, 'context': document},
+    {'type': 'pALLOW', 'allow': false, 'context': document},
+    {'type': 'pDENY', 'allow': true, 'context': document},
+    {'type': 'pPROMPT', 'allow': true, 'context': document},
+    {'type': 'pSESSION', 'allow': true, 'context': document},
+    {'type': 'pREMOVE', 'remove': true, 'context': document},
+  ], test3);
+}
+
+async function test3() {
+  ok(await SpecialPowers.testPermission('pUNKNOWN', ALLOW_ACTION, document), 'pUNKNOWN value should have ALLOW permission');
+  ok(await SpecialPowers.testPermission('pPROMPT', ALLOW_ACTION, document), 'pPROMPT value should have ALLOW permission');
+  ok(await SpecialPowers.testPermission('pALLOW', DENY_ACTION, document), 'pALLOW should have DENY permission');
+  ok(await SpecialPowers.testPermission('pDENY', ALLOW_ACTION, document), 'pDENY should have ALLOW permission');
+  ok(await SpecialPowers.testPermission('pREMOVE', UNKNOWN_ACTION, document), 'pREMOVE should have REMOVE permission');
+  ok(await SpecialPowers.testPermission('pSESSION', ALLOW_ACTION, document), 'pSESSION should have ALLOW permission');
+
+  // only pPROMPT (last one) is different, the other stuff is just to see if it doesn't cause test failures
+  SpecialPowers.pushPermissions([
+    {'type': 'pUNKNOWN', 'allow': true, 'context': document},
+    {'type': 'pALLOW', 'allow': false, 'context': document},
+    {'type': 'pDENY', 'allow': true, 'context': document},
+    {'type': 'pPROMPT', 'allow': false, 'context': document},
+    {'type': 'pREMOVE', 'remove': true, 'context': document},
+  ], test3b);
+}
+
+async function test3b() {
+  ok(await SpecialPowers.testPermission('pPROMPT', DENY_ACTION, document), 'pPROMPT value should have DENY permission');
+  SpecialPowers.pushPermissions([
+    {'type': 'pUNKNOWN', 'allow': DENY_ACTION, 'context': document},
+    {'type': 'pALLOW', 'allow': PROMPT_ACTION, 'context': document},
+    {'type': 'pDENY', 'allow': PROMPT_ACTION, 'context': document},
+    {'type': 'pPROMPT', 'allow': ALLOW_ACTION, 'context': document},
+  ], test4);
+}
+
+async function test4() {
+  ok(await SpecialPowers.testPermission('pUNKNOWN', DENY_ACTION, document), 'pUNKNOWN value should have DENY permission');
+  ok(await SpecialPowers.testPermission('pPROMPT', ALLOW_ACTION, document), 'pPROMPT value should have ALLOW permission');
+  ok(await SpecialPowers.testPermission('pALLOW', PROMPT_ACTION, document), 'pALLOW should have PROMPT permission');
+  ok(await SpecialPowers.testPermission('pDENY', PROMPT_ACTION, document), 'pDENY should have PROMPT permission');
+  //this should reset all the permissions to before all the pushPermissions calls
+  SpecialPowers.flushPermissions(test5);
+}
+
+async function test5() {
+  ok(await SpecialPowers.testPermission('pUNKNOWN', UNKNOWN_ACTION, document), 'pUNKNOWN should have UNKNOWN permission');
+  ok(await SpecialPowers.testPermission('pALLOW', ALLOW_ACTION, document), 'pALLOW should have ALLOW permission');
+  ok(await SpecialPowers.testPermission('pDENY', DENY_ACTION, document), 'pDENY should have DENY permission');
+  ok(await SpecialPowers.testPermission('pPROMPT', PROMPT_ACTION, document), 'pPROMPT should have PROMPT permission');
+  ok(await SpecialPowers.testPermission('pREMOVE', ALLOW_ACTION, document), 'pREMOVE should have ALLOW permission');
+  ok(await SpecialPowers.testPermission('pSESSION', ACCESS_SESSION, document), 'pSESSION should have ACCESS_SESSION permission');
+
+  SpecialPowers.removePermission("pPROMPT", document);
+  SpecialPowers.removePermission("pALLOW", document);
+  SpecialPowers.removePermission("pDENY", document);
+  SpecialPowers.removePermission("pREMOVE", document);
+  SpecialPowers.removePermission("pSESSION", document);
+
+  setTimeout(test6, 0);
+}
+
+async function test6() {
+  if (!await SpecialPowers.testPermission('pALLOW', UNKNOWN_ACTION, document)) {
+    dump('/**** allow still set ****/\n');
+    setTimeout(test6, 0);
+  } else if (!await SpecialPowers.testPermission('pDENY', UNKNOWN_ACTION, document)) {
+    dump('/**** deny still set ****/\n');
+    setTimeout(test6, 0);
+  } else if (!await SpecialPowers.testPermission('pPROMPT', UNKNOWN_ACTION, document)) {
+    dump('/**** prompt still set ****/\n');
+    setTimeout(test6, 0);
+  } else if (!await SpecialPowers.testPermission('pREMOVE', UNKNOWN_ACTION, document)) {
+    dump('/**** remove still set ****/\n');
+    setTimeout(test6, 0);
+  } else if (!await SpecialPowers.testPermission('pSESSION', UNKNOWN_ACTION, document)) {
+    dump('/**** pSESSION still set ****/\n');
+    setTimeout(test6, 0);
+  } else {
+    test7();
+  }
+}
+
+function test7() {
+  afterPermissionChanged('pEXPIRE', 'deleted', test8);
+  afterPermissionChanged('pEXPIRE', 'added', permissionPollingCheck);
+  start = Number(Date.now());
+  SpecialPowers.addPermission('pEXPIRE',
+                              true,
+                              document,
+                              EXPIRE_TIME,
+                              (start + PERIOD + getPlatformInfo().timeCompensation));
+}
+
+function test8() {
+  afterPermissionChanged('pEXPIRE', 'deleted', SimpleTest.finish);
+  afterPermissionChanged('pEXPIRE', 'added', permissionPollingCheck);
+  start = Number(Date.now());
+  SpecialPowers.pushPermissions([
+    { 'type': 'pEXPIRE',
+      'allow': true,
+      'expireType': EXPIRE_TIME,
+      'expireTime': (start + PERIOD + getPlatformInfo().timeCompensation),
+      'context': document
+    }], function() {
+      info("Wait for permission-changed signal!");
+    }
+  );
+}
+
+function afterPermissionChanged(type, op, callback) {
+  // handle the message from specialPowers_framescript.js
+  gScript.addMessageListener('perm-changed', function onChange(msg) {
+    if (msg.type == type && msg.op == op) {
+      gScript.removeMessageListener('perm-changed', onChange);
+      callback();
+    }
+  });
+}
+
+async function permissionPollingCheck() {
+  var now = Number(Date.now());
+  if (now < (start + PERIOD)) {
+    if (await SpecialPowers.testPermission('pEXPIRE', ALLOW_ACTION, document)) {
+      // To make sure that permission will be expired in next round,
+      // the next permissionPollingCheck calling will be fired 100ms later after
+      // permission is out-of-period.
+      setTimeout(permissionPollingCheck, PERIOD + 100);
+      return;
+    }
+
+    errorHandler('unexpired permission should be allowed!');
+  }
+
+  // The permission is already expired!
+  if (await SpecialPowers.testPermission('pEXPIRE', ALLOW_ACTION, document)) {
+    errorHandler('expired permission should be removed!');
+  }
+}
+
+function getPlatformInfo() {
+  var version = SpecialPowers.Services.sysinfo.getProperty('version');
+  version = parseFloat(version);
+
+  // PR_Now() that called in PermissionManager to get the system time and
+  // Date.now() are out of sync on win32 platform(XP/win7). The PR_Now() is
+  // 15~20ms less than Date.now(). Unfortunately, this time skew can't be
+  // avoided, so it needs to add a time buffer to compensate.
+  // Version 5.1 is win XP, 6.1 is win7
+  if (navigator.platform.startsWith('Win32') && (version <= 6.1)) {
+    return { platform: "Win32", timeCompensation: -100 };
+  }
+
+  return { platform: "NoMatter", timeCompensation: 0 };
+}
+
+function errorHandler(msg) {
+  ok(false, msg);
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersPushPrefEnv.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersPushPrefEnv.html
new file mode 100644
index 0000000000..727f17349b
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersPushPrefEnv.html
@@ -0,0 +1,232 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers extension</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body onload="starttest();">
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+async function starttest() {
+  try {
+    await SpecialPowers.setBoolPref("test.bool", 1);
+  } catch(e) {
+    await SpecialPowers.setBoolPref("test.bool", true);
+  }
+  try {
+    await SpecialPowers.setIntPref("test.int", true);
+  } catch(e) {
+    await SpecialPowers.setIntPref("test.int", 1);
+  }
+  await SpecialPowers.setCharPref("test.char", 'test');
+  await SpecialPowers.setBoolPref("test.cleanup", false);
+
+  setTimeout(test1, 0, 0);
+}
+
+SimpleTest.waitForExplicitFinish();
+
+function test1(aCount) {
+  if (aCount >= 20) {
+    ok(false, "Too many times attempting to set pref, aborting");
+    SimpleTest.finish();
+    return;
+  }
+
+  try {
+    is(SpecialPowers.getBoolPref('test.bool'), true, 'test.bool should be true');
+  } catch(e) {
+    setTimeout(test1, 0, ++aCount);
+    return;
+  }
+
+  try {
+    is(SpecialPowers.getIntPref('test.int'), 1, 'test.int should be 1');
+  } catch(e) {
+    setTimeout(test1, 0, ++aCount);
+    return;
+  }
+
+  try {
+    is(SpecialPowers.getCharPref('test.char'), 'test', 'test.char should be test');
+  } catch(e) {
+    setTimeout(test1, 0, ++aCount);
+    return;
+  }
+
+  test2();
+}
+
+function test2() {
+  // test non-changing values
+  SpecialPowers.pushPrefEnv({"set": [["test.bool", true], ["test.int", 1], ["test.char", "test"]]}, test3);
+}
+
+function test3() {
+  // test changing char pref using the Promise
+  is(SpecialPowers.getBoolPref('test.bool'), true, 'test.bool should be true');
+  is(SpecialPowers.getIntPref('test.int'), 1, 'test.int should be 1');
+  is(SpecialPowers.getCharPref('test.char'), 'test', 'test.char should be test');
+  SpecialPowers.pushPrefEnv({"set": [["test.bool", true], ["test.int", 1], ["test.char", "test2"]]}).then(test4);
+}
+
+function test4() {
+  // test changing all values and adding test.char2 pref
+  is(SpecialPowers.getCharPref('test.char'), 'test2', 'test.char should be test2');
+  SpecialPowers.pushPrefEnv({"set": [["test.bool", false], ["test.int", 10], ["test.char", "test2"], ["test.char2", "test"]]}, test5);
+}
+
+function test5() {
+  // test flushPrefEnv
+  is(SpecialPowers.getBoolPref('test.bool'), false, 'test.bool should be false');
+  is(SpecialPowers.getIntPref('test.int'), 10, 'test.int should be 10');
+  is(SpecialPowers.getCharPref('test.char'), 'test2', 'test.char should be test2');
+  is(SpecialPowers.getCharPref('test.char2'), 'test', 'test.char2 should be test');
+  SpecialPowers.flushPrefEnv(test6);
+}
+
+function test6() {
+  // test clearing prefs
+  is(SpecialPowers.getBoolPref('test.bool'), true, 'test.bool should be true');
+  is(typeof SpecialPowers.getBoolPref('test.bool'), typeof true, 'test.bool should be boolean');
+  is(SpecialPowers.getIntPref('test.int'), 1, 'test.int should be 1');
+  is(typeof SpecialPowers.getIntPref('test.int'), typeof 1, 'test.int should be integer');
+  is(SpecialPowers.getCharPref('test.char'), 'test', 'test.char should be test');
+  is(typeof SpecialPowers.getCharPref('test.char'), typeof 'test', 'test.char should be String');
+  try {
+    SpecialPowers.getCharPref('test.char2');
+    ok(false, 'This ok should not be reached!');
+  } catch(e) {
+    ok(true, 'getCharPref("test.char2") should throw');
+  }
+  SpecialPowers.pushPrefEnv({"clear": [["test.bool"], ["test.int"], ["test.char"], ["test.char2"]]}, test6b);
+}
+
+function test6b() {
+  // test if clearing another time doesn't cause issues
+  SpecialPowers.pushPrefEnv({"clear": [["test.bool"], ["test.int"], ["test.char"], ["test.char2"]]}, test7);
+}
+
+function test7() {
+  try {
+    SpecialPowers.getBoolPref('test.bool');
+    ok(false, 'This ok should not be reached!');
+  } catch(e) {
+    ok(true, 'getBoolPref("test.bool") should throw');
+  }
+
+  try {
+    SpecialPowers.getIntPref('test.int');
+    ok(false, 'This ok should not be reached!');
+  } catch(e) {
+    ok(true, 'getIntPref("test.int") should throw');
+  }
+
+  try {
+    SpecialPowers.getCharPref('test.char');
+    ok(false, 'This ok should not be reached!');
+  } catch(e) {
+    ok(true, 'getCharPref("test.char") should throw');
+  }
+
+  try {
+    SpecialPowers.getCharPref('test.char2');
+    ok(false, 'This ok should not be reached!');
+  } catch(e) {
+    ok(true, 'getCharPref("test.char2") should throw');
+  }
+
+  SpecialPowers.flushPrefEnv().then(test8);
+}
+
+function test8() {
+  is(SpecialPowers.getBoolPref('test.bool'), true, 'test.bool should be true');
+  is(typeof SpecialPowers.getBoolPref('test.bool'), typeof true, 'test.bool should be boolean');
+  is(SpecialPowers.getIntPref('test.int'), 1, 'test.int should be 1');
+  is(typeof SpecialPowers.getIntPref('test.int'), typeof 1, 'test.int should be integer');
+  is(SpecialPowers.getCharPref('test.char'), 'test', 'test.char should be test');
+  is(typeof SpecialPowers.getCharPref('test.char'), typeof 'test', 'test.char should be String');
+  try {
+    SpecialPowers.getCharPref('test.char2');
+    ok(false, 'This ok should not be reached!');
+  } catch(e) {
+    ok(true, 'getCharPref("test.char2") should throw');
+  }
+  SpecialPowers.clearUserPref("test.bool");
+  SpecialPowers.clearUserPref("test.int");
+  SpecialPowers.clearUserPref("test.char");
+  setTimeout(test9, 0, 0);
+}
+
+function test9(aCount) {
+  if (aCount >= 20) {
+    ok(false, "Too many times attempting to set pref, aborting");
+    SimpleTest.finish();
+    return;
+  }
+
+  try {
+    SpecialPowers.getBoolPref('test.bool');
+    setTimeout(test9, 0, ++aCount);
+  } catch(e) {
+    test10(0);
+  }
+}
+
+function test10(aCount) {
+  if (aCount >= 20) {
+    ok(false, "Too many times attempting to set pref, aborting");
+    SimpleTest.finish();
+    return;
+  }
+
+  try {
+    SpecialPowers.getIntPref('test.int');
+    setTimeout(test10, 0, ++aCount);
+  } catch(e) {
+    test11(0);
+  }
+}
+
+function test11(aCount) {
+  if (aCount >= 20) {
+    ok(false, "Too many times attempting to set pref, aborting");
+    SimpleTest.finish();
+    return;
+  }
+
+  try {
+    SpecialPowers.getCharPref('test.char');
+    setTimeout(test11, 0, ++aCount);
+  } catch(e) {
+    test12();
+  }
+}
+
+function test12() {
+  // Set test.cleanup to true via pushPrefEnv, while its default value is false.
+  SpecialPowers.pushPrefEnv({"set": [["test.cleanup", true]]}, () => {
+    // Update the preference manually back to its original value.
+    SpecialPowers.setBoolPref("test.cleanup", false);
+    setTimeout(test13, 0);
+  });
+}
+
+function test13() {
+  // Try to flush preferences. Since test.cleanup has manually been set to false, there
+  // will not be any visible update. Check that the flush does not timeout.
+  SpecialPowers.flushPrefEnv(() => {
+    ok(true, 'flushPrefEnv did not time out');
+    is(SpecialPowers.getBoolPref('test.cleanup'), false, 'test.cleanup should be false');
+    SimpleTest.finish();
+  });
+}
+
+// todo - test non-changing values, test complex values, test mixing of pushprefEnv 'set' and 'clear'
+// When bug 776424 gets fixed, getPref doesn't throw anymore, so this test would have to be changed accordingly
+</script>
+</pre>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSandbox.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSandbox.html
new file mode 100644
index 0000000000..7946a18236
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSandbox.html
@@ -0,0 +1,125 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers sandboxes</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<iframe id="iframe"></iframe>
+
+<script>
+/**
+ * Tests that the shared sandbox functionality for cross-process script
+ * execution works as expected. In particular, ensures that Assert methods
+ * report the correct diagnostics in the caller scope.
+ */
+
+/* globals SpecialPowers, Assert */
+
+async function interceptDiagnostics(func) {
+  let originalRecord = SimpleTest.record;
+  try {
+    let diags = [];
+
+    SimpleTest.record = (condition, name, diag, stack) => {
+      diags.push({condition, name, diag, stack});
+    };
+
+    await func();
+
+    return diags;
+  } finally {
+    SimpleTest.record = originalRecord;
+  }
+}
+
+add_task(async function() {
+  const frameSrc = "https://example.com/tests/testing/mochitest/tests/Harness_sanity/file_spawn.html";
+  const subframeSrc = "https://example.org/tests/testing/mochitest/tests/Harness_sanity/file_spawn.html";
+
+  let frame = document.getElementById("iframe");
+  frame.src = frameSrc;
+
+  await new Promise(resolve => {
+    frame.addEventListener("load", resolve, {once: true});
+  });
+
+  let expected = [
+    [false, "Thing - 1 == 2", "got 1, expected 2 (operator ==)"],
+    [true, "Hmm - 1 == 1", undefined],
+    [true, "Yay. - true == true", undefined],
+    [false, "Boo!. - false == true", "got false, expected true (operator ==)"],
+  ];
+
+  // Test that a representative variety of assertions work as expected, and
+  // trigger the expected calls to the harness's reporting function.
+  //
+  // Note: Assert.sys.mjs has its own tests, and defers all of its reporting to a
+  // single reporting function, so we don't need to test it comprehensively. We
+  // just need to make sure that the general functionality works as expected.
+  let tests = {
+    "SpecialPowers.spawn": () => {
+      return SpecialPowers.spawn(frame, [], async () => {
+        Assert.equal(1, 2, "Thing");
+        Assert.equal(1, 1, "Hmm");
+        Assert.ok(true, "Yay.");
+        Assert.ok(false, "Boo!.");
+      });
+    },
+    "SpecialPowers.spawn-subframe": () => {
+      return SpecialPowers.spawn(frame, [subframeSrc], async src => {
+        let subFrame = this.content.document.createElement("iframe");
+        subFrame.src = src;
+        this.content.document.body.appendChild(subFrame);
+
+        await new Promise(resolve => {
+          subFrame.addEventListener("load", resolve, { once: true });
+        });
+
+        await SpecialPowers.spawn(subFrame, [], () => {
+          Assert.equal(1, 2, "Thing");
+          Assert.equal(1, 1, "Hmm");
+          Assert.ok(true, "Yay.");
+          Assert.ok(false, "Boo!.");
+        });
+      });
+    },
+    "SpecialPowers.spawnChrome": () => {
+      return SpecialPowers.spawnChrome([], async () => {
+        Assert.equal(1, 2, "Thing");
+        Assert.equal(1, 1, "Hmm");
+        Assert.ok(true, "Yay.");
+        Assert.ok(false, "Boo!.");
+      });
+    },
+    "SpecialPowers.loadChromeScript": async () => {
+      let script = SpecialPowers.loadChromeScript(() => {
+        /* eslint-env mozilla/chrome-script */
+        this.addMessageListener("ping", () => "pong");
+
+        Assert.equal(1, 2, "Thing");
+        Assert.equal(1, 1, "Hmm");
+        Assert.ok(true, "Yay.");
+        Assert.ok(false, "Boo!.");
+      });
+
+      await script.sendQuery("ping");
+      script.destroy();
+    },
+  };
+
+  for (let [name, func] of Object.entries(tests)) {
+    info(`Starting task: ${name}`);
+
+    let diags = await interceptDiagnostics(func);
+
+    let results = diags.map(diag => [diag.condition, diag.name, diag.diag]);
+
+    isDeeply(results, expected, "Got expected assertions");
+  }
+});
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSandbox.js b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSandbox.js
new file mode 100644
index 0000000000..42ec471bb8
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSandbox.js
@@ -0,0 +1,139 @@
+"use strict";
+
+/* eslint-disable @microsoft/sdl/no-insecure-url */
+
+const { XPCShellContentUtils } = ChromeUtils.import(
+  "resource://testing-common/XPCShellContentUtils.jsm"
+);
+
+XPCShellContentUtils.init(this);
+
+const HTML = String.raw`<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title></title>
+</head>
+<body>
+  <span id="span">Hello there.</span>
+</body>
+</html>`;
+
+const server = XPCShellContentUtils.createHttpServer({
+  hosts: ["example.com", "example.org"],
+});
+
+server.registerPathHandler("/", (request, response) => {
+  response.setHeader("Content-Type", "text/html");
+  response.write(HTML);
+});
+/**
+ * Tests that the shared sandbox functionality for cross-process script
+ * execution works as expected. In particular, ensures that Assert methods
+ * report the correct diagnostics in the caller scope.
+ */
+
+let scope = this;
+
+async function interceptDiagnostics(func) {
+  let originalRecord = scope.do_report_result;
+  try {
+    let diags = [];
+
+    scope.do_report_result = (passed, msg, stack) => {
+      diags.push({ passed, msg, stack });
+    };
+
+    await func();
+
+    return diags;
+  } finally {
+    scope.do_report_result = originalRecord;
+  }
+}
+
+add_task(async function () {
+  const frameSrc = "http://example.com/";
+  const subframeSrc = "http://example.org/";
+
+  let page = await XPCShellContentUtils.loadContentPage(frameSrc, {
+    remote: true,
+    remoteSubframes: true,
+  });
+
+  let { SpecialPowers, browsingContext } = page;
+
+  let expected = [
+    [false, "Thing - 1 == 2"],
+    [true, "Hmm - 1 == 1"],
+    [true, "Yay. - true == true"],
+    [false, "Boo!. - false == true"],
+  ];
+
+  // Test that a representative variety of assertions work as expected, and
+  // trigger the expected calls to the harness's reporting function.
+  //
+  // Note: Assert.sys.mjs has its own tests, and defers all of its reporting to a
+  // single reporting function, so we don't need to test it comprehensively. We
+  // just need to make sure that the general functionality works as expected.
+  let tests = {
+    "SpecialPowers.spawn": () => {
+      return SpecialPowers.spawn(browsingContext, [], async () => {
+        Assert.equal(1, 2, "Thing");
+        Assert.equal(1, 1, "Hmm");
+        Assert.ok(true, "Yay.");
+        Assert.ok(false, "Boo!.");
+      });
+    },
+    "SpecialPowers.spawn-subframe": () => {
+      return SpecialPowers.spawn(browsingContext, [subframeSrc], async src => {
+        let subFrame = this.content.document.createElement("iframe");
+        subFrame.src = src;
+        this.content.document.body.appendChild(subFrame);
+
+        await new Promise(resolve => {
+          subFrame.addEventListener("load", resolve, { once: true });
+        });
+
+        await SpecialPowers.spawn(subFrame, [], () => {
+          Assert.equal(1, 2, "Thing");
+          Assert.equal(1, 1, "Hmm");
+          Assert.ok(true, "Yay.");
+          Assert.ok(false, "Boo!.");
+        });
+      });
+    },
+    "SpecialPowers.spawnChrome": () => {
+      return SpecialPowers.spawnChrome([], async () => {
+        Assert.equal(1, 2, "Thing");
+        Assert.equal(1, 1, "Hmm");
+        Assert.ok(true, "Yay.");
+        Assert.ok(false, "Boo!.");
+      });
+    },
+    "SpecialPowers.loadChromeScript": async () => {
+      let script = SpecialPowers.loadChromeScript(() => {
+        /* eslint-env mozilla/chrome-script */
+        this.addMessageListener("ping", () => "pong");
+
+        Assert.equal(1, 2, "Thing");
+        Assert.equal(1, 1, "Hmm");
+        Assert.ok(true, "Yay.");
+        Assert.ok(false, "Boo!.");
+      });
+
+      await script.sendQuery("ping");
+      script.destroy();
+    },
+  };
+
+  for (let [name, func] of Object.entries(tests)) {
+    info(`Starting task: ${name}`);
+
+    let diags = await interceptDiagnostics(func);
+
+    let results = diags.map(diag => [diag.passed, diag.msg]);
+
+    deepEqual(results, expected, "Got expected assertions");
+  }
+});
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.html
new file mode 100644
index 0000000000..fe93c1fe83
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.html
@@ -0,0 +1,69 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers.spawn</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<iframe id="iframe"></iframe>
+
+<span id="hello">World.</span>
+
+<script>
+/* globals SpecialPowers, content */
+
+  add_task(async function() {
+    let frame = document.getElementById("iframe");
+    frame.src = "https://example.com/tests/testing/mochitest/tests/Harness_sanity/file_spawn.html";
+
+    await new Promise(resolve => {
+      frame.addEventListener("load", resolve, {once: true});
+    });
+
+    let result = await SpecialPowers.spawn(frame, ["#span"], selector => {
+      let elem = content.document.querySelector(selector);
+      return elem.textContent;
+    });
+
+    is(result, "Hello there.", "Got correct element text from frame");
+
+    /* eslint-disable no-shadow */
+    result = await SpecialPowers.spawn(frame, ["#hello"], selector => {
+      return SpecialPowers.spawn(content.parent, [selector], selector => {
+        let elem = content.document.querySelector(selector);
+        return elem.textContent;
+      });
+    });
+
+    is(result, "World.", "Got correct element text from frame's window.parent");
+
+    result = await SpecialPowers.spawn(frame.contentWindow, ["#span"], selector => {
+      let elem = content.document.querySelector(selector);
+      return elem.textContent;
+    });
+
+    is(result, "Hello there.", "Got correct element text from window proxy");
+
+    result = await SpecialPowers.spawn(SpecialPowers.getPrivilegedProps(frame, "browsingContext"),
+                                       ["#span"], selector => {
+      let elem = content.document.querySelector(selector);
+      return elem.textContent;
+    });
+
+    is(result, "Hello there.", "Got correct element text from browsing context");
+
+    let line = 58; // Keep this in sync with the line number where the callback function starts.
+    let callback = () => {
+      let e = new Error("Hello.");
+      return { filename: e.fileName, lineNumber: e.lineNumber };
+    };
+
+    let loc = await SpecialPowers.spawn(frame, [], callback);
+    is(loc.filename, location.href, "Error should have correct script filename");
+    is(loc.lineNumber, line + 2, "Error should have correct script line number");
+  });
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.js b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.js
new file mode 100644
index 0000000000..06c8dc3c59
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawn.js
@@ -0,0 +1,68 @@
+"use strict";
+
+const { XPCShellContentUtils } = ChromeUtils.import(
+  "resource://testing-common/XPCShellContentUtils.jsm"
+);
+
+XPCShellContentUtils.init(this);
+
+const HTML = String.raw`<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title></title>
+</head>
+<body>
+  <span id="span">Hello there.</span>
+</body>
+</html>`;
+
+const server = XPCShellContentUtils.createHttpServer({
+  hosts: ["example.com"],
+});
+
+server.registerPathHandler("/", (request, response) => {
+  response.setHeader("Content-Type", "text/html");
+  response.write(HTML);
+});
+
+add_task(async function () {
+  // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+  let page = await XPCShellContentUtils.loadContentPage("http://example.com/", {
+    remote: true,
+    remoteSubframes: true,
+  });
+
+  let { SpecialPowers, browsingContext } = page;
+
+  let result = await SpecialPowers.spawn(
+    browsingContext,
+    ["#span"],
+    selector => {
+      let elem = content.document.querySelector(selector);
+      return elem.textContent;
+    }
+  );
+
+  equal(result, "Hello there.", "Got correct element text from frame");
+
+  let line = Components.stack.lineNumber + 1;
+  let callback = () => {
+    let e = new Error("Hello.");
+    return { filename: e.fileName, lineNumber: e.lineNumber };
+  };
+
+  let loc = await SpecialPowers.spawn(browsingContext, [], callback);
+  equal(
+    loc.filename,
+    Components.stack.filename,
+    "Error should have correct script filename"
+  );
+  equal(
+    loc.lineNumber,
+    line + 2,
+    "Error should have correct script line number"
+  );
+
+  await page.close();
+});
diff --git a/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawnChrome.html b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawnChrome.html
new file mode 100644
index 0000000000..9c3f1ee658
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_SpecialPowersSpawnChrome.html
@@ -0,0 +1,32 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers.spawnChrome</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<script>
+  add_task(async function() {
+    let { browsingContextId, innerWindowId } = await SpecialPowers.spawnChrome([12, { b: 42 }], (a, b) => {
+      Assert.equal(a, 12, "Arg 1");
+      Assert.equal(b.b, 42, "Arg 2");
+
+      Assert.equal(Services.appinfo.processType,
+                   Services.appinfo.PROCESS_TYPE_DEFAULT,
+                   "Task runs in correct process");
+
+      return {
+        browsingContextId: browsingContext.id,
+        innerWindowId: windowGlobalParent.innerWindowId,
+      };
+    });
+
+    let wgc = SpecialPowers.wrap(window).windowGlobalChild;
+    is(browsingContextId, wgc.browsingContext.id, "Correct browsing context id");
+    is(innerWindowId, wgc.innerWindowId, "Correct inner window id");
+  });
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_TestsRunningAfterSimpleTestFinish.html b/testing/mochitest/tests/Harness_sanity/test_TestsRunningAfterSimpleTestFinish.html
new file mode 100644
index 0000000000..aa0a7d39ef
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_TestsRunningAfterSimpleTestFinish.html
@@ -0,0 +1,23 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for whether SimpLeTest.ok after SimpleTest.finish is causing an error to be logged</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<div id="content" class="testbody">
+  <script type="text/javascript">
+    SimpleTest.waitForExplicitFinish();
+    addLoadEvent(function() {
+      ok(true, "This should pass");
+      SimpleTest.finish();
+    });
+    window.onbeforeunload = function() {
+      ok(true, "This should cause failures in the harness, because it's run after SimpleTest.finish()");
+    }
+  </script>
+</div>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_bug649012.html b/testing/mochitest/tests/Harness_sanity/test_bug649012.html
new file mode 100644
index 0000000000..8807aa56f3
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_bug649012.html
@@ -0,0 +1,37 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=649012
+-->
+<head>
+  <title>Test for Bug 649012</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=649012">Mozilla Bug 649012</a>
+<p id="display"></p>
+<div id="content">
+</div>
+<pre id="test">
+<script type="application/javascript">
+
+/** Test for Bug 649012 **/
+SimpleTest.waitForExplicitFinish();
+addLoadEvent(function() {
+  // Test that setTimeout(f, 0) doesn't raise an error
+  setTimeout(function() {
+    // Test that setTimeout(f, t) where t > 0 doesn't raise an error if we've used
+    // SimpleTest.requestFlakyTimeout
+    SimpleTest.requestFlakyTimeout("Just testing to make sure things work.  I would never do this in real life of course!");
+    setTimeout(function() {
+      SimpleTest.finish();
+    }, 1);
+  }, 0);
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_createFiles.html b/testing/mochitest/tests/Harness_sanity/test_createFiles.html
new file mode 100644
index 0000000000..0e0637a230
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_createFiles.html
@@ -0,0 +1,91 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers.createFiles</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<div id="content" class="testbody">
+  <script type="text/javascript">
+    // Creating one file, followed by failing to create a file.
+    function test1() {
+      const fileType = "some file type";
+      let fdata = "this is same data for a file";
+      SpecialPowers.createFiles([{name: "test1.txt", data:fdata, options:{type:fileType}}],
+        function (files) {
+          is(files.length, 1, "Created 1 file");
+          let f = files[0];
+          is("[object File]", f.toString(), "first thing in array is a file");
+          is(f.size, fdata.length, "test1 size of first file should be length of its data");
+          is("test1.txt", f.name, "test1 test file should have the right name");
+          is(f.type, fileType, "File should have the specified type");
+          test2();
+        },
+        function (msg) { ok(false, "Should be able to create a file without an error"); test2(); }
+      );
+    }
+
+    // Failing to create a file, followed by creating a file.
+    function test2() {
+      function test3Check(passed) {
+        ok(passed, "Should trigger the error handler for a bad file name.");
+        test3();
+      };
+
+      SpecialPowers.createFiles([{name: "/\/\/\/\/\/\/\/\/\/\/\invalidname",}],
+        function () { test3Check(false); },
+        function (msg) { test3Check(true); }
+      );
+    }
+
+    // Creating two files at the same time.
+    function test3() {
+      let f1data = "hello";
+      SpecialPowers.createFiles([{name: "test3_file.txt", data:f1data}, {name: "emptyfile.txt"}],
+        function (files) {
+          is(files.length, 2, "Expected two files to be created");
+          let f1 = files[0];
+          let f2 = files[1];
+          is("[object File]", f1.toString(), "first thing in array is a file");
+          is("[object File]", f2.toString(), "second thing in array is a file");
+          is("test3_file.txt", f1.name, "first test3 test file should have the right name");
+          is("emptyfile.txt", f2.name, "second test3 test file should have the right name");
+          is(f1.size, f1data.length, "size of first file should be length of its data");
+          is(f2.size, 0, "size of second file should be 0");
+          test4();
+        },
+        function (msg) {
+          ok(false, "Failed to create files: " + msg);
+          test4();
+        }
+      );
+    };
+
+    // Creating a file without specifying a name should work.
+    function test4() {
+      let fdata = "this is same data for a file";
+      SpecialPowers.createFiles([{data:fdata}],
+        function (files) {
+          is(files.length, 1, "Created 1 file");
+          let f = files[0];
+          is("[object File]", f.toString(), "first thing in array is a file");
+          is(f.size, fdata.length, "test4 size of first file should be length of its data");
+          ok(f.name, "test4 test file should have a name");
+          SimpleTest.finish();
+        },
+        function (msg) {
+          ok(false, "Should be able to create a file without a name without an error");
+          SimpleTest.finish();
+        }
+      );
+    }
+
+    SimpleTest.waitForExplicitFinish();
+    test1();
+
+  </script>
+</div>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_getweakmapkeys.html b/testing/mochitest/tests/Harness_sanity/test_getweakmapkeys.html
new file mode 100644
index 0000000000..58722d977f
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_getweakmapkeys.html
@@ -0,0 +1,26 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers.nondeterministicGetWeakMapKeys</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<div id="content" class="testbody">
+  <script type="text/javascript">
+    var emptyMap = new WeakMap;
+    is(SpecialPowers.nondeterministicGetWeakMapKeys(emptyMap).length, 0, "Empty map has no keys");
+    var twoMap = new WeakMap;
+    var x = {};
+    var y = {};
+    twoMap.set(x, 1);
+    twoMap.set(y, 2);
+    var twoMapKeys = SpecialPowers.nondeterministicGetWeakMapKeys(twoMap);
+    is(twoMapKeys.length, 2, "Map with two things should have two keys");
+    ok(twoMapKeys[0] == x || twoMapKeys[1] == x, "One of the keys should be x");
+    ok(twoMapKeys[0] == y || twoMapKeys[1] == y, "One of the keys should be y");
+  </script>
+</div>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_importInMainProcess.html b/testing/mochitest/tests/Harness_sanity/test_importInMainProcess.html
new file mode 100644
index 0000000000..10e5aa6526
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_importInMainProcess.html
@@ -0,0 +1,56 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for SpecialPowers.importInMainProcess</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<div id="content" class="testbody">
+  <script type="text/javascript">
+    SimpleTest.waitForExplicitFinish();
+
+    (async () => {
+      var failed = false;
+      try {
+        await SpecialPowers.importInMainProcess("invalid file for import");
+      } catch (e) {
+        ok(e.toString().indexOf("NS_ERROR_MALFORMED_URI") > -1, "Exception should be for a malformed URI");
+        failed = true;
+      }
+      ok(failed, "An invalid import should throw");
+
+      const testingResource = "resource://testing-common/ImportTesting.jsm";
+      var script = SpecialPowers.loadChromeScript(SimpleTest.getTestFileURL('importtesting_chromescript.js'));
+
+      script.addMessageListener("ImportTesting:IsModuleLoadedReply", handleFirstReply);
+      script.sendAsyncMessage("ImportTesting:IsModuleLoaded", testingResource);
+
+      async function handleFirstReply(aMsg) {
+        ok(!aMsg, "ImportTesting.jsm shouldn't be loaded before we import it");
+
+        try {
+          await SpecialPowers.importInMainProcess(testingResource);
+        } catch (e) {
+          ok(false, "Unexpected exception when importing a valid resource: " + e.toString());
+        }
+
+        script.removeMessageListener("ImportTesting:IsModuleLoadedReply", handleFirstReply);
+        script.addMessageListener("ImportTesting:IsModuleLoadedReply", handleSecondReply);
+        script.sendAsyncMessage("ImportTesting:IsModuleLoaded", testingResource);
+      }
+
+      function handleSecondReply(aMsg) {
+        script.removeMessageListener("ImportTesting:IsModuleLoadedReply", handleSecondReply);
+
+        ok(aMsg, "ImportTesting.jsm should be loaded after we import it");
+
+        SimpleTest.finish();
+      }
+    })();
+
+  </script>
+</div>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanity.html b/testing/mochitest/tests/Harness_sanity/test_sanity.html
new file mode 100644
index 0000000000..e40ccca35b
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanity.html
@@ -0,0 +1,62 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for mochitest harness sanity</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=">Mozilla Bug </a>
+<p id="display">
+  <input id="testKeyEvent1" onkeypress="press1 = true">
+  <input id="testKeyEvent2" onkeydown="return false;" onkeypress="press2 = true">
+  <input id="testKeyEvent3" onkeypress="press3 = true">
+  <input id="testKeyEvent4" onkeydown="return false;" onkeypress="press4 = true">
+</p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for sanity  **/
+ok(true, "true must be ok");
+isnot(1, true, "1 must not be true");
+isnot(1, false, "1 must not be false");
+isnot(0, false, "0 must not be false");
+isnot(0, true, "0 must not be true");
+isnot("", 0, "Empty string must not be 0");
+isnot("1", 1, "Numeric string must not equal the number");
+isnot("", null, "Empty string must not be null");
+isnot(undefined, null, "Undefined must not be null");
+
+var press1 = false;
+$("testKeyEvent1").focus();
+sendString("x");
+is($("testKeyEvent1").value, "x", "synthesizeKey should work");
+is(press1, true, "synthesizeKey should dispatch keyPress");
+
+var press2 = false;
+$("testKeyEvent2").focus();
+sendString("x");
+is($("testKeyEvent2").value, "", "synthesizeKey should respect keydown preventDefault");
+is(press2, false, "synthesizeKey should not dispatch keyPress with default prevented");
+
+var press3 = false;
+$("testKeyEvent3").focus();
+sendChar("x")
+is($("testKeyEvent3").value, "x", "sendChar should work");
+is(press3, true, "sendChar should dispatch keyPress");
+
+var press4 = false;
+$("testKeyEvent4").focus();
+sendChar("x")
+is($("testKeyEvent4").value, "", "sendChar should respect keydown preventDefault");
+is(press4, false, "sendChar should not dispatch keyPress with default prevented");
+
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanityEventUtils.html b/testing/mochitest/tests/Harness_sanity/test_sanityEventUtils.html
new file mode 100644
index 0000000000..f2e0b0bda6
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanityEventUtils.html
@@ -0,0 +1,692 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Profiling test suite for EventUtils</title>
+  <script type="text/javascript">
+  var start = new Date();
+  </script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript">
+  var loadTime = new Date();
+  </script>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body onload="starttest()">
+<input type="radio" id="radioTarget1" name="group">Radio Target 1</input>
+<input id="textBoxA">
+<input id="textBoxB">
+<input id="testMouseEvent" type="button" value="click">
+<input id="testKeyEvent" >
+<input id="testStrEvent" >
+<div id="scrollB" style="width: 190px;height: 250px;overflow:auto">
+<p>blah blah blah blah</p>
+<p>blah blah blah blah</p>
+<p>blah blah blah blah</p>
+<p>blah blah blah blah</p>
+<p>blah blah blah blah</p>
+<p>blah blah blah blah</p>
+<p>blah blah blah blah</p>
+<p>blah blah blah blah</p>
+</div>
+<script class="testbody" type="text/javascript">
+info("\nProfile::EventUtilsLoadTime: " + (loadTime - start) + "\n");
+function starttest() {
+  SimpleTest.waitForFocus(
+    async function () {
+      SimpleTest.waitForExplicitFinish();
+      var startTime = new Date();
+      var check = false;
+      function doCheck() {
+        check = true;
+      }
+
+      const kIsHeadless = await SpecialPowers.spawnChrome([], () => {
+        return Cc["@mozilla.org/gfx/info;1"].getService(Ci.nsIGfxInfo).isHeadless;
+      });
+
+      if (navigator.appVersion.includes("Android")) {
+        // This is the workaround for test failure on debug build.
+        await SpecialPowers.pushPrefEnv({set: [["formhelper.autozoom.force-disable.test-only", true]]});
+      }
+
+      /* test send* functions */
+      $("testMouseEvent").addEventListener("click", doCheck, {once: true});
+      sendMouseEvent({type:'click'}, "testMouseEvent");
+      is(check, true, 'sendMouseEvent should dispatch click event');
+
+      await (async function testSynthesizeNativeMouseEvent() {
+        let events = [];
+        let listener = event => events.push(event);
+        let preventDefault = event => event.preventDefault();
+        $("testMouseEvent").addEventListener("mousedown", listener);
+        $("testMouseEvent").addEventListener("mouseup", listener);
+        // Clicking with modifiers may open context menu so that we should prevent to open it.
+        window.addEventListener("contextmenu", preventDefault, { capture: true });
+        for (const test of [
+            {
+              description: "ShiftLeft",
+              modifiers: { shiftKey: true },
+            },
+            {
+              description: "ShiftRight",
+              modifiers: { shiftRightKey: true },
+            },
+            {
+              description: "CtrlLeft",
+              modifiers: { ctrlKey: true },
+            },
+            {
+              description: "CtrlRight",
+              modifiers: { ctrlRightKey: true },
+            },
+            {
+              description: "AltLeft",
+              modifiers: { altKey: true },
+            },
+            {
+              description: "AltRight",
+              modifiers: { altRightKey: true },
+            },
+            {
+              description: "MetaLeft",
+              modifiers: { metaKey: true },
+              skip: () => {
+                // We've not supported "Meta" as Windows logo key or Super/Hyper keys.
+                return navigator.platform.includes("Win") || navigator.platform.includes("Linux");
+              },
+            },
+            {
+              description: "MetaRight",
+              modifiers: { metaRightKey: true },
+              skip: () => {
+                // We've not supported "Meta" as Windows logo key or Super/Hyper keys.
+                return navigator.platform.includes("Win") || navigator.platform.includes("Linux");
+              },
+            },
+            {
+              description: "CapsLock",
+              modifiers: { capsLockKey: true },
+            },
+            {
+              description: "NumLock",
+              modifiers: { numLockKey: true },
+              skip: () => {
+                // macOS does not have `NumLock` key nor state.
+                return navigator.platform.includes("Mac");
+              },
+            },
+            {
+              description: "Ctrl+Shift",
+              modifiers: { ctrlKey: true, shiftKey: true },
+              skip: () => {
+                // We forcibly open context menu on macOS so the following test
+                // will fail to receive mouse events.
+                return navigator.platform.includes("Mac");
+              },
+            },
+            {
+              description: "Alt+Shift",
+              modifiers: { altKey: true, shiftKey: true },
+            },
+            {
+              description: "Meta+Shift",
+              modifiers: { metaKey: true, shiftKey: true },
+              skip: () => {
+                // We've not supported "Meta" as Windows logo key or Super/Hyper keys.
+                return navigator.platform.includes("Win") || navigator.platform.includes("Linux");
+              },
+            },
+          ]) {
+          if (test.skip && test.skip()) {
+            continue;
+          }
+          events = [];
+          info(`testSynthesizeNativeMouseEvent: sending native mouse click (${test.description})`);
+          await promiseNativeMouseEventAndWaitForEvent({
+            type: "click",
+            target: $("testMouseEvent"),
+            atCenter: true,
+            modifiers: test.modifiers,
+            eventTypeToWait: "mouseup",
+          });
+          is(events.length, 2,
+            `testSynthesizeNativeMouseEvent: a pair of "mousedown" and "mouseup" events should be fired (${test.description})`);
+          is(events[0]?.type, "mousedown",
+            `testSynthesizeNativeMouseEvent: "mousedown" should be fired (${test.description})`);
+          is(events[1]?.type, "mouseup",
+            `testSynthesizeNativeMouseEvent: "mouseup" should be fired (${test.description})`);
+          if (events.length !== 2) {
+            continue;
+          }
+          for (const mod of [{ keyName: "Alt",      propNames: [ "altKey", "altRightKey" ]},
+                             { keyName: "Control",  propNames: [ "ctrlKey", "ctrlRightKey" ]},
+                             { keyName: "Shift",    propNames: [ "shiftKey", "shiftRightKey" ]},
+                             { keyName: "Meta",     propNames: [ "metaKey", "metaRightKey" ]},
+                             { keyName: "CapsLock", propNames: [ "capsLockKey" ]},
+                             { keyName: "NumLock",  propNames: [ "numLockKey" ]},
+                            ]) {
+            const activeExpected =
+              (test.modifiers.hasOwnProperty(mod.propNames[0]) &&
+               test.modifiers[mod.propNames[0]]) ||
+                (mod.propNames.length !== 1 &&
+                 test.modifiers.hasOwnProperty(mod.propNames[1]) &&
+                 test.modifiers[mod.propNames[1]]);
+            const checkFn = activeExpected && (
+              // Bug 1693240: We don't support setting modifiers while posting a mouse event on Windows.
+              navigator.platform.includes("Win") ||
+              // Bug 1693237: We don't support setting modifiers on Android.
+              navigator.appVersion.includes("Android") ||
+              // In Headless mode, modifiers are not supported by this kind of APIs.
+              kIsHeadless) ? todo_is : is;
+            checkFn(events[0]?.getModifierState(mod.keyName), activeExpected,
+              `testSynthesizeNativeMouseEvent: "mousedown".getModifierState("${mod.keyName}") should return ${activeExpected} (${test.description}`);
+            checkFn(events[1]?.getModifierState(mod.keyName), activeExpected,
+              `testSynthesizeNativeMouseEvent: "mouseup".getModifierState("${mod.keyName}") should return ${activeExpected} (${test.description}`);
+          }
+        }
+        const supportsX1AndX2Buttons =
+          // On Windows, it triggers APP_COMMAND.  Therefore, this test is unloaded.
+          !navigator.platform.includes("Win") &&
+          // On macOS, it seems that no API to specify X1 and X2 button at creating an NSEvent.
+          !navigator.platform.includes("Mac") &&
+          // On Linux, it seems that X1 button and X2 button events are not synthesized correctly.
+          !navigator.platform.includes("Linux");
+        for (let i = 0; i < (supportsX1AndX2Buttons ? 5 : 3); i++) {
+          events = [];
+          info(`testSynthesizeNativeMouseEvent: sending native mouse click (button=${i})`);
+          await promiseNativeMouseEventAndWaitForEvent({
+            type: "click",
+            target: $("testMouseEvent"),
+            atCenter: true,
+            button: i,
+            eventTypeToWait: "mouseup",
+          });
+          is(events.length, 2,
+            `testSynthesizeNativeMouseEvent: a pair of "mousedown" and "mouseup" events should be fired (button=${i})`);
+          is(events[0]?.type, "mousedown",
+            `testSynthesizeNativeMouseEvent: "mousedown" should be fired (button=${i})`);
+          is(events[1]?.type, "mouseup",
+            `testSynthesizeNativeMouseEvent: "mouseup" should be fired (button=${i})`);
+          if (events.length !== 2) {
+            continue;
+          }
+          is(events[0].button, i,
+            `testSynthesizeNativeMouseEvent: button of "mousedown" event should be ${i}`);
+          is(events[1].button, i,
+            `testSynthesizeNativeMouseEvent: button of "mouseup" event should be ${i}`);
+        }
+        $("testMouseEvent").removeEventListener("mousedown", listener);
+        $("testMouseEvent").removeEventListener("mouseup", listener);
+        window.removeEventListener("contextmenu", preventDefault, { capture: true });
+      })();
+
+      check = false;
+      $("testKeyEvent").addEventListener("keypress", doCheck, {once: true});
+      $("testKeyEvent").focus();
+      sendChar("x");
+      is($("testKeyEvent").value, "x", "sendChar should work");
+      is(check, true, "sendChar should dispatch keyPress");
+      $("testKeyEvent").value = "";
+
+      $("testStrEvent").focus();
+      sendString("string");
+      is($("testStrEvent").value, "string", "sendString should work");
+      $("testStrEvent").value = "";
+
+      var keydown = false;
+      var keypress = false;
+      $("testKeyEvent").focus();
+      $("testKeyEvent").addEventListener("keydown", function() { keydown = true; }, {once: true});
+      $("testKeyEvent").addEventListener("keypress", function() { keypress = true; }, {once: true});
+      sendKey("DOWN");
+      ok(keydown, "sendKey should dispatch keyDown");
+      ok(!keypress, "sendKey shouldn't dispatch keyPress for non-printable key");
+
+      /* test synthesizeMouse* */
+      //focus trick enables us to run this in iframes
+      $("radioTarget1").addEventListener('focus', function (aEvent) {
+        synthesizeMouse($("radioTarget1"), 1, 1, {});
+        is($("radioTarget1").checked, true, "synthesizeMouse should work")
+        $("radioTarget1").checked = false;
+        disableNonTestMouseEvents(true);
+        synthesizeMouse($("radioTarget1"), 1, 1, {});
+        is($("radioTarget1").checked, true, "synthesizeMouse should still work with non-test mouse events disabled");
+        $("radioTarget1").checked = false;
+        disableNonTestMouseEvents(false);
+      }, {once: true});
+      $("radioTarget1").focus();
+
+      //focus trick enables us to run this in iframes
+      $("textBoxA").addEventListener("focus", function (aEvent) {
+        check = false;
+        $("textBoxA").addEventListener("click", function() { check = true; }, { once: true });
+        synthesizeMouseAtCenter($("textBoxA"), {});
+        is(check, true, 'synthesizeMouse should dispatch mouse event');
+
+        check = false;
+        $("scrollB").addEventListener("click", function() { check = true; }, { once: true });
+        synthesizeMouseExpectEvent($("scrollB"), 1, 1, {}, $("scrollB"), "click", "synthesizeMouseExpectEvent should fire click event");
+        is(check, true, 'synthesizeMouse should dispatch mouse event');
+      }, {once: true});
+      $("textBoxA").focus();
+
+      /**
+       * TODO: testing synthesizeWheel requires a setTimeout
+       * since there is delay between the scroll event and a check, so for now just test
+       * that we can successfully call it to avoid having setTimeout vary the runtime metric.
+       * Testing of this method is currently done here:
+       * toolkit/content/tests/chrome/test_mousescroll.xul
+       */
+      synthesizeWheel($("scrollB"), 5, 5, {'deltaY': 10.0, deltaMode: WheelEvent.DOM_DELTA_LINE});
+
+      /* test synthesizeKey* */
+      check = false;
+      $("testKeyEvent").addEventListener("keypress", doCheck, {once:true});
+      $("testKeyEvent").focus();
+      sendString("a");
+      is($("testKeyEvent").value, "a", "synthesizeKey should work");
+      is(check, true, "synthesizeKey should dispatch keyPress");
+      $("testKeyEvent").value = "";
+
+      // If |.code| value is not specified explicitly, it should be computed
+      // from the |.key| value or |.keyCode| value.  If a printable key is
+      // specified, the |.code| value should be guessed with US-English
+      // keyboard layout.
+      for (let test of [{ arg: "KEY_Enter", code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN },
+                        { arg: "VK_RETURN", code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN },
+                        { arg: "KEY_Backspace", code: "Backspace", keyCode: KeyboardEvent.DOM_VK_BACK_SPACE },
+                        { arg: "KEY_Delete", code: "Delete", keyCode: KeyboardEvent.DOM_VK_DELETE },
+                        { arg: "KEY_Home", code: "Home", keyCode: KeyboardEvent.DOM_VK_HOME },
+                        { arg: "KEY_End", code: "End", keyCode: KeyboardEvent.DOM_VK_END },
+                        { arg: "KEY_ArrowDown", code: "ArrowDown", keyCode: KeyboardEvent.DOM_VK_DOWN },
+                        { arg: "KEY_ArrowUp", code: "ArrowUp", keyCode: KeyboardEvent.DOM_VK_UP },
+                        { arg: "KEY_ArrowLeft", code: "ArrowLeft", keyCode: KeyboardEvent.DOM_VK_LEFT },
+                        { arg: "KEY_ArrowRight", code: "ArrowRight", keyCode: KeyboardEvent.DOM_VK_RIGHT },
+                        { arg: "KEY_Shift", code: "ShiftLeft", keyCode: KeyboardEvent.DOM_VK_SHIFT },
+                        { arg: "KEY_Control", code: "ControlLeft", keyCode: KeyboardEvent.DOM_VK_CONTROL },
+                        { arg: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A },
+                        { arg: "B", code: "KeyB", keyCode: KeyboardEvent.DOM_VK_B },
+                        { arg: " ", code: "Space", keyCode: KeyboardEvent.DOM_VK_SPACE },
+                        { arg: "0", code: "Digit0", keyCode: KeyboardEvent.DOM_VK_0 },
+                        { arg: "(", code: "Digit9", keyCode: KeyboardEvent.DOM_VK_9 },
+                        { arg: "!", code: "Digit1", keyCode: KeyboardEvent.DOM_VK_1 },
+                        { arg: "[", code: "BracketLeft", keyCode: KeyboardEvent.DOM_VK_OPEN_BRACKET },
+                        { arg: ";", code: "Semicolon", keyCode: KeyboardEvent.DOM_VK_SEMICOLON },
+                        { arg: "\"", code: "Quote", keyCode: KeyboardEvent.DOM_VK_QUOTE },
+                        { arg: "~", code: "Backquote", keyCode: KeyboardEvent.DOM_VK_BACK_QUOTE },
+                        { arg: "<", code: "Comma", keyCode: KeyboardEvent.DOM_VK_COMMA },
+                        { arg: ".", code: "Period", keyCode: KeyboardEvent.DOM_VK_PERIOD }]) {
+        let testKeydown, keyup;
+        $("testKeyEvent").focus();
+        $("testKeyEvent").addEventListener("keydown", (e) => { testKeydown = e; }, {once: true});
+        $("testKeyEvent").addEventListener("keyup", (e) => { keyup = e; }, {once: true});
+        synthesizeKey(test.arg);
+        is(testKeydown.code, test.code, `Synthesizing "${test.arg}" should set code value of "keydown" to "${test.code}"`);
+        is(testKeydown.keyCode, test.keyCode, `Synthesizing "${test.arg}" should set keyCode value of "keydown" to "${test.keyCode}"`);
+        is(keyup.code, test.code, `Synthesizing "${test.arg}" key should set code value of "keyup" to "${test.code}"`);
+        is(keyup.keyCode, test.keyCode, `Synthesizing "${test.arg}" key should set keyCode value of "keyup" to "${test.keyCode}"`);
+        $("testKeyEvent").value = "";
+      }
+
+      /* test synthesizeComposition */
+      var description = "";
+      var keydownEvent = null;
+      var keyupEvent = null;
+      function onKeyDown(aEvent) {
+        ok(!keydownEvent, description + "keydown should be fired only once" + (keydownEvent ? keydownEvent.key : "") + ", " + (keyupEvent ? keyupEvent.key : ""));
+        keydownEvent = aEvent;
+      }
+      function onKeyUp(aEvent) {
+        ok(!keyupEvent, description + "keyup should be fired only once");
+        keyupEvent = aEvent;
+      }
+      function resetKeyDownAndKeyUp(aDescription) {
+        description = aDescription + ": ";
+        keydownEvent = null;
+        keyupEvent = null;
+        check = false;
+      }
+      function checkKeyDownAndKeyUp(aKeyDown, aKeyUp) {
+        if (aKeyDown) {
+          is(keydownEvent.keyCode, aKeyDown.keyCode,
+             description + "keydown event should be dispatched (checking keyCode)");
+          is(keydownEvent.key, aKeyDown.key,
+             description + "keydown event should be dispatched (checking key)");
+        } else {
+          is(keydownEvent, null,
+             description + "keydown event shouldn't be fired");
+        }
+        if (aKeyUp) {
+          is(keyupEvent.keyCode, aKeyUp.keyCode,
+             description + "keyup event should be dispatched (checking keyCode)");
+          is(keyupEvent.key, aKeyUp.key,
+             description + "keyup event should be dispatched (checking key)");
+        } else {
+          is(keyupEvent, null,
+             description + "keyup event shouldn't be fired");
+        }
+      }
+      $("textBoxB").addEventListener("keydown", onKeyDown);
+      $("textBoxB").addEventListener("keyup", onKeyUp);
+
+      $("textBoxB").focus();
+
+      // If key event is not specified, fake keydown and keyup events which are
+      // marked as "processed by IME" should be fired.
+      resetKeyDownAndKeyUp("synthesizing eCompositionStart without specifying keyboard event");
+      window.addEventListener("compositionstart", doCheck, {once: true});
+      synthesizeComposition({type: "compositionstart"});
+      ok(check, description + "synthesizeComposition() should dispatch compositionstart");
+      checkKeyDownAndKeyUp({inComposition: false, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"});
+
+      resetKeyDownAndKeyUp("trying to synthesize eCompositionUpdate directly without specifying keyboard event");
+      window.addEventListener("compositionupdate", doCheck, {once: true});
+      synthesizeComposition({type: "compositionupdate", data: "a"});
+      ok(!check, description + "synthesizeComposition() should not dispatch compositionupdate without error");
+      checkKeyDownAndKeyUp(null, null);
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange without specifying keyboard event");
+      window.addEventListener("text", doCheck, {once: true});
+      synthesizeCompositionChange(
+        { "composition":
+          { "string": "a",
+            "clauses":
+            [
+              { "length": 1, "attr": COMPOSITION_ATTR_RAW_CLAUSE }
+            ]
+          },
+          "caret": { "start": 1, "length": 0 }
+        }
+      );
+      ok(check, description + "synthesizeCompositionChange should cause dispatching a DOM text event");
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange for removing clauses without specifying keyboard event");
+      synthesizeCompositionChange(
+        { "composition":
+          { "string": "a",
+            "clauses":
+            [
+              { "length": 0, "attr": 0 }
+            ]
+          },
+          "caret": { "start": 1, "length": 0 }
+        }
+      );
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"});
+
+      resetKeyDownAndKeyUp("trying to synthesize eCompositionEnd directly without specifying keyboard event");
+      window.addEventListener("compositionend", doCheck, {once: true});
+      synthesizeComposition({type: "compositionend", data: "a"});
+      ok(!check, description + "synthesizeComposition() should not dispatch compositionend");
+      checkKeyDownAndKeyUp(null, null);
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionCommit without specifying keyboard event");
+      synthesizeComposition({type: "compositioncommit", data: "a"});
+      ok(check, description + "synthesizeComposition() should dispatch compositionend");
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: false, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"});
+
+      var querySelectedText = synthesizeQuerySelectedText();
+      ok(querySelectedText, "query selected text event result is null");
+      ok(querySelectedText.succeeded, "query selected text event failed");
+      is(querySelectedText.offset, 1,
+         "query selected text event returns wrong offset");
+      is(querySelectedText.text, "",
+         "query selected text event returns wrong selected text");
+      $("textBoxB").value = "";
+
+      querySelectedText = synthesizeQuerySelectedText();
+      ok(querySelectedText, "query selected text event result is null");
+      ok(querySelectedText.succeeded, "query selected text event failed");
+      is(querySelectedText.offset, 0,
+         "query selected text event returns wrong offset");
+      is(querySelectedText.text, "",
+         "query selected text event returns wrong selected text");
+      var endTime = new Date();
+      info("\nProfile::EventUtilsRunTime: " + (endTime-startTime) + "\n");
+
+      // In most cases, automated tests shouldn't try to synthesize
+      // compositionstart manually.  Let's check if synthesizeCompositionChange()
+      // dispatches compositionstart automatically.
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange without specifying keyboard event when there is no composition");
+      window.addEventListener("compositionstart", doCheck, {once: true});
+      synthesizeCompositionChange(
+        { "composition":
+          { "string": "a",
+            "clauses":
+            [
+              { "length": 1, "attr": COMPOSITION_ATTR_RAW_CLAUSE }
+            ]
+          },
+          "caret": { "start": 1, "length": 0 }
+        }
+      );
+      ok(check, description + "synthesizeCompositionChange should dispatch \"compositionstart\" automatically if there is no composition");
+      checkKeyDownAndKeyUp({inComposition: false, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionCommitAsIs without specifying keyboard event");
+      synthesizeComposition({type: "compositioncommitasis"});
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: false, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"});
+
+      // If key event is specified, keydown event which is marked as "processed
+      // by IME" should be fired and keyup event which is NOT marked as so
+      // should be fired too.
+      resetKeyDownAndKeyUp("synthesizing eCompositionStart with specifying keyboard event");
+      synthesizeComposition({type: "compositionstart", key: {key: "a"}});
+      checkKeyDownAndKeyUp({inComposition: false, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_A, key: "a"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange with specifying keyboard event");
+      synthesizeCompositionChange(
+        {"composition":
+          {"string": "b", "clauses": [
+             {"length": 1, "attr": COMPOSITION_ATTR_RAW_CLAUSE}
+           ]},
+          "caret": {"start": 1, "length": 0},
+          "key": {key: "b"},
+        }
+      );
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_B, key: "b"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionCommit with specifying keyboard event");
+      synthesizeComposition({type: "compositioncommit", data: "c", key: {key: "KEY_Enter"}});
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: false, keyCode: KeyboardEvent.DOM_VK_RETURN, key: "Enter"});
+
+      // keyup shouldn't be dispatched automatically if type is specified as keydown
+      resetKeyDownAndKeyUp("synthesizing eCompositionStart with specifying keyboard event whose type is keydown");
+      synthesizeComposition({type: "compositionstart", key: {key: "a", type: "keydown"}});
+      checkKeyDownAndKeyUp({inComposition: false, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           null);
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange with specifying keyboard event whose type is keydown");
+      synthesizeCompositionChange(
+        {"composition":
+          {"string": "b", "clauses": [
+             {"length": 1, "attr": COMPOSITION_ATTR_RAW_CLAUSE}
+           ]},
+          "caret": {"start": 1, "length": 0},
+          "key": {key: "b", type: "keydown"},
+        }
+      );
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           null);
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionCommit with specifying keyboard event whose type is keydown");
+      synthesizeComposition({type: "compositioncommit", data: "c", key: {key: "KEY_Enter", type: "keydown"}});
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           null);
+
+      // keydown shouldn't be dispatched automatically if type is specified as keyup
+      resetKeyDownAndKeyUp("synthesizing eCompositionStart with specifying keyboard event whose type is keyup");
+      synthesizeComposition({type: "compositionstart", key: {key: "a", type: "keyup"}});
+      checkKeyDownAndKeyUp(null,
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_A, key: "a"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange with specifying keyboard event whose type is keyup");
+      synthesizeCompositionChange(
+        {"composition":
+          {"string": "b", "clauses": [
+             {"length": 1, "attr": COMPOSITION_ATTR_RAW_CLAUSE}
+           ]},
+          "caret": {"start": 1, "length": 0},
+          "key": {key: "b", type: "keyup"},
+        }
+      );
+      checkKeyDownAndKeyUp(null,
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_B, key: "b"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionCommit with specifying keyboard event whose type is keyup");
+      synthesizeComposition({type: "compositioncommit", data: "c", key: {key: "KEY_Enter", type: "keyup"}});
+      checkKeyDownAndKeyUp(null,
+                           {inComposition: false, keyCode: KeyboardEvent.DOM_VK_RETURN, key: "Enter"});
+
+      // keydown event shouldn't be marked as "processed by IME" if doNotMarkKeydownAsProcessed is true
+      resetKeyDownAndKeyUp("synthesizing eCompositionStart with specifying keyboard event whose doNotMarkKeydownAsProcessed is true");
+      synthesizeComposition({type: "compositionstart", key: {key: "a", doNotMarkKeydownAsProcessed: true}});
+      checkKeyDownAndKeyUp({inComposition: false, keyCode: KeyboardEvent.DOM_VK_A, key: "a"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_A, key: "a"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange with specifying keyboard event whose doNotMarkKeydownAsProcessed is true");
+      synthesizeCompositionChange(
+        {"composition":
+          {"string": "b", "clauses": [
+             {"length": 1, "attr": COMPOSITION_ATTR_RAW_CLAUSE}
+           ]},
+          "caret": {"start": 1, "length": 0},
+          "key": {key: "b", doNotMarkKeydownAsProcessed: true},
+        }
+      );
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_B, key: "b"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_B, key: "b"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionCommit with specifying keyboard event whose doNotMarkKeydownAsProcessed is true");
+      synthesizeComposition({type: "compositioncommit", data: "c", key: {key: "KEY_Enter", doNotMarkKeydownAsProcessed: true}});
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_RETURN, key: "Enter"},
+                           {inComposition: false, keyCode: KeyboardEvent.DOM_VK_RETURN, key: "Enter"});
+
+      // keyup event should be marked as "processed by IME" if markKeyupAsProcessed is true
+      resetKeyDownAndKeyUp("synthesizing eCompositionStart with specifying keyboard event whose markKeyupAsProcessed is true");
+      synthesizeComposition({type: "compositionstart", key: {key: "a", markKeyupAsProcessed: true}});
+      checkKeyDownAndKeyUp({inComposition: false, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange with specifying keyboard event whose markKeyupAsProcessed is true");
+      synthesizeCompositionChange(
+        {"composition":
+          {"string": "b", "clauses": [
+             {"length": 1, "attr": COMPOSITION_ATTR_RAW_CLAUSE}
+           ]},
+          "caret": {"start": 1, "length": 0},
+          "key": {key: "b", markKeyupAsProcessed: true},
+        }
+      );
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"});
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionCommit with specifying keyboard event whose markKeyupAsProcessed is true");
+      synthesizeComposition({type: "compositioncommit", data: "c", key: {key: "KEY_Enter", markKeyupAsProcessed: true}});
+      checkKeyDownAndKeyUp({inComposition: true, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"},
+                           {inComposition: false, keyCode: KeyboardEvent.DOM_VK_PROCESSKEY, key: "Process"});
+
+      // If key event is explicitly declared with null, keyboard events shouldn't
+      // be fired for emulating text inputs without keyboard such as voice input or something.
+      resetKeyDownAndKeyUp("synthesizing eCompositionStart with specifying keyboard event as null");
+      synthesizeComposition({type: "compositionstart", key: null});
+      checkKeyDownAndKeyUp(null, null);
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange with specifying keyboard event as null");
+      synthesizeCompositionChange(
+        {"composition":
+          {"string": "b", "clauses": [
+             {"length": 1, "attr": COMPOSITION_ATTR_RAW_CLAUSE}
+           ]},
+          "caret": {"start": 1, "length": 0},
+          "key": null,
+        }
+      );
+      checkKeyDownAndKeyUp(null, null);
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionCommit with specifying keyboard event as null");
+      synthesizeComposition({type: "compositioncommit", data: "c", key: null});
+      checkKeyDownAndKeyUp(null, null);
+
+      // If key event is explicitly declared with empty object, keyboard events
+      // shouldn't be fired for emulating text inputs without keyboard such as
+      // voice input or something.
+      resetKeyDownAndKeyUp("synthesizing eCompositionStart with specifying keyboard event as empty");
+      synthesizeComposition({type: "compositionstart", key: {}});
+      checkKeyDownAndKeyUp(null, null);
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionChange with specifying keyboard event as empty");
+      synthesizeCompositionChange(
+        {"composition":
+          {"string": "b", "clauses": [
+             {"length": 1, "attr": COMPOSITION_ATTR_RAW_CLAUSE}
+           ]},
+          "caret": {"start": 1, "length": 0},
+          "key": {},
+        }
+      );
+      checkKeyDownAndKeyUp(null, null);
+
+      resetKeyDownAndKeyUp("synthesizing eCompositionCommit with specifying keyboard event as empty");
+      synthesizeComposition({type: "compositioncommit", data: "c", key: {}});
+      checkKeyDownAndKeyUp(null, null);
+
+      $("textBoxB").removeEventListener("keydown", onKeyDown);
+      $("textBoxB").removeEventListener("keyup", onKeyUp);
+
+
+      // Async event synthesizing.
+      // On Android this does not work.
+      if (navigator.userAgent.includes("Android")) {
+        SimpleTest.finish();
+        return;
+      }
+
+      await (async function () {
+        await SpecialPowers.pushPrefEnv({set: [["test.events.async.enabled", true]]});
+        try {
+          disableNonTestMouseEvents(true);
+          let mouseMoveCount = 0;
+          let waitForAllSynthesizedMouseMove =
+            new Promise(resolve => {
+              window.addEventListener("mousemove", function onMouseMove(aEvent) {
+                mouseMoveCount++;
+                is(aEvent.target, $("testMouseEvent"),
+                  `The mousemove event target of ${
+                    mouseMoveCount
+                  } should be the input#testMouseEvent, but ${
+                    aEvent.target.nodeName
+                  }`);
+                if (mouseMoveCount === 30) {
+                  window.removeEventListener("mousemove", onMouseMove, { capture: true });
+                  resolve();
+                }
+              }, { capture: true });
+            });
+          for (let i = 0; i < 30; i++) {
+            synthesizeMouse($("testMouseEvent"), 3 + i % 2, 3 + i % 2, { type: "mousemove" });
+          }
+          await waitForAllSynthesizedMouseMove;
+        } finally {
+          disableNonTestMouseEvents(false);
+        }
+      })();
+
+      SimpleTest.finish();
+    }
+  );
+};
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanityException.html b/testing/mochitest/tests/Harness_sanity/test_sanityException.html
new file mode 100644
index 0000000000..463f51d80e
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanityException.html
@@ -0,0 +1,16 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>Test that uncaught exceptions in mochitests cause failures</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=670817">Mozilla Bug 670817</a>
+<script>
+ok(true, "a call to ok");
+SimpleTest.expectUncaughtException();
+// eslint-disable-next-line no-throw-literal
+throw "an uncaught exception";
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanityException2.html b/testing/mochitest/tests/Harness_sanity/test_sanityException2.html
new file mode 100644
index 0000000000..1136b73916
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanityException2.html
@@ -0,0 +1,22 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>Test that uncaught exceptions in mochitests cause failures</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=670817">Mozilla Bug 670817</a>
+<script>
+SimpleTest.waitForExplicitFinish();
+ok(true, "a call to ok");
+SimpleTest.executeSoon(function() {
+  SimpleTest.expectUncaughtException();
+  // eslint-disable-next-line no-throw-literal
+  throw "an uncaught exception";
+});
+SimpleTest.executeSoon(function() {
+  SimpleTest.finish();
+});
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanityParams.html b/testing/mochitest/tests/Harness_sanity/test_sanityParams.html
new file mode 100644
index 0000000000..192d6ef96a
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanityParams.html
@@ -0,0 +1,13 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test for exposing test suite information</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script class="testbody" type="text/javascript">
+ok(SimpleTest.harnessParameters, "Should have parameters.");
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanityRegisteredServiceWorker.html b/testing/mochitest/tests/Harness_sanity/test_sanityRegisteredServiceWorker.html
new file mode 100644
index 0000000000..f3c6d422d9
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanityRegisteredServiceWorker.html
@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>Test that service worker registrations not cleaned up in mochitests cause failures</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+</head>
+<body>
+<script>
+SimpleTest.waitForExplicitFinish();
+SimpleTest.expectRegisteredServiceWorker();
+SpecialPowers.pushPrefEnv({"set": [
+  ["dom.serviceWorkers.exemptFromPerDomainMax", true],
+  ["dom.serviceWorkers.enabled", true],
+  ["dom.serviceWorkers.testing.enabled", true]
+]}, function() {
+  navigator.serviceWorker.register("empty.js", {scope: "scope"})
+    .then(function(registration) {
+      ok(registration, "Registration succeeded");
+      SimpleTest.finish();
+    });
+});
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanityRegisteredServiceWorker2.html b/testing/mochitest/tests/Harness_sanity/test_sanityRegisteredServiceWorker2.html
new file mode 100644
index 0000000000..f46944c2e5
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanityRegisteredServiceWorker2.html
@@ -0,0 +1,25 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>Test that service worker registrations not cleaned up in mochitests cause failures</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+</head>
+<body>
+<script>
+SimpleTest.waitForExplicitFinish();
+SpecialPowers.pushPrefEnv({"set": [
+  ["dom.serviceWorkers.exemptFromPerDomainMax", true],
+  ["dom.serviceWorkers.enabled", true],
+  ["dom.serviceWorkers.testing.enabled", true]
+]}, function() {
+  navigator.serviceWorker.getRegistration("scope")
+    .then(function(registration) {
+      ok(registration, "Registration successfully obtained");
+      return registration.unregister();
+    }).then(function() {
+      SimpleTest.finish();
+    });
+});
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanitySimpletest.html b/testing/mochitest/tests/Harness_sanity/test_sanitySimpletest.html
new file mode 100644
index 0000000000..2b289f1387
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanitySimpletest.html
@@ -0,0 +1,103 @@
+<!--This test should be updated each time new functionality is added to SimpleTest-->
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Profiling test suite for SimpleTest</title>
+  <script type="text/javascript">
+  var start = new Date();
+  </script>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+  <script type="text/javascript">
+  var loadTime = new Date();
+  </script>
+</head>
+<body>
+<input id="textB"/>
+<script class="testbody" type="text/javascript">
+info("Profile::SimpleTestLoadTime: " + (loadTime - start));
+var startTime = new Date();
+SimpleTest.waitForExplicitFinish();
+function starttest() {
+  SimpleTest.waitForFocus(
+    function() {
+      //test log
+      info("Logging some info")
+
+      //basic usage
+      ok(true, "test ok");
+      SimpleTest.record(true, "test ok", "diagnostic information");
+      is(0, 0, "is() test failed");
+      isnot(0, 1, "isnot() test failed");
+
+      //todo tests
+      todo(false, "test todo", "todo() test should not pass");
+      todo_is(false, true, "test todo_is");
+      todo_isnot(true, true, "test todo_isnot");
+
+      //misc
+      SimpleTest.requestLongerTimeout(1);
+
+      //note: this test may alter runtimes as it waits
+      var check = false;
+      $('textB').focus();
+      SimpleTest.waitForClipboard("a",
+        function () {
+          SpecialPowers.clipboardCopyString("a");
+        },
+        function () {
+          check = true;
+          is(check, true, "waitForClipboard should work");
+          manipulateElements();
+        },
+        function () {
+          check = false;
+          is(check, false, "waitForClipboard should work");
+          manipulateElements();
+        }
+      );
+
+      //use helper functions
+      function manipulateElements()
+      {
+        var div1 = createEl('div', {'id': 'somediv', 'display': 'block'}, "I am a div");
+        document.body.appendChild(div1);
+        var divObj = this.getElement('somediv');
+        is(divObj, div1, 'createEl did not create element as expected');
+        is($('somediv'), divObj, '$ helper did not get element as expected');
+        is(computedStyle(divObj, 'display'), 'block', 'computedStyle did not get right display value');
+        document.body.removeChild(div1);
+
+        /* note: expectChildProcessCrash is not being tested here, as it causes wildly variable
+         * run times. It is currently being tested in:
+         *  dom/plugins/test/test_hanging.html and dom/plugins/test/test_crashing.html
+         */
+
+        //note: this also adds a short wait period
+        SimpleTest.executeSoon(
+          function () {
+            //finish() calls a slew of SimpleTest functions
+            SimpleTest.finish();
+            //call this after finish so we can make sure it works and doesn't hang our process
+            var endTime = new Date();
+            info("Profile::SimpleTestRunTime: " + (endTime-startTime));
+            //expect and throw exception here. Otherwise, any code that follows the throw call will never be executed
+            SimpleTest.expectUncaughtException();
+            //make sure we catch this error
+            // eslint-disable-next-line no-throw-literal
+            throw "i am an uncaught exception"
+          }
+        );
+      }
+    }
+  );
+};
+//use addLoadEvent
+addLoadEvent(
+  function() {
+    starttest();
+  }
+);
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanityWindowSnapshot.html b/testing/mochitest/tests/Harness_sanity/test_sanityWindowSnapshot.html
new file mode 100644
index 0000000000..6960fc2104
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanityWindowSnapshot.html
@@ -0,0 +1,35 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Profiling test suite for WindowSnapshot</title>
+  <script type="text/javascript">
+  var start = new Date();
+  </script>
+  <script src="/tests/SimpleTest/WindowSnapshot.js"></script>
+  <script type="text/javascript">
+  var loadTime = new Date();
+  </script>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body onload="starttest()">
+<script class="testbody" type="text/javascript">
+info("\nProfile::WindowSnapshotLoadTime: " + (loadTime - start) + "\n");
+function starttest() {
+  SimpleTest.waitForExplicitFinish();
+  var startTime = new Date();
+  var snap = snapshotWindow(window, false);
+  var snap2 = snapshotWindow(window, false);
+  is(compareSnapshots(snap, snap2, true)[0], true, "this should be true");
+  var div1 = createEl('div', {'id': 'somediv', 'display': 'block'}, "I am a div");
+  document.body.appendChild(div1);
+  snap2 = snapshotWindow(window, false);
+  is(compareSnapshots(snap, snap2, true)[0], false, "this should be false");
+  document.body.removeChild(div1);
+  var endTime = new Date();
+  info("\nProfile::WindowSnapshotRunTime: " + (endTime-startTime) + "\n");
+  SimpleTest.finish();
+};
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanity_cleanup.html b/testing/mochitest/tests/Harness_sanity/test_sanity_cleanup.html
new file mode 100644
index 0000000000..644be67674
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanity_cleanup.html
@@ -0,0 +1,30 @@
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>SimpleTest.registerCleanupFunction test</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script class="testbody" type="text/javascript">
+// Not a great example, since we have the pushPrefEnv API to cover
+// this use case, but I want to be able to test that the cleanup
+// function gets run, so setting and clearing a pref seems straightforward.
+function do_cleanup1() {
+  SpecialPowers.clearUserPref("simpletest.cleanup.1");
+  info("do_cleanup1 run!");
+}
+function do_cleanup2() {
+  SpecialPowers.clearUserPref("simpletest.cleanup.2");
+  info("do_cleanup2 run!");
+}
+SpecialPowers.setBoolPref("simpletest.cleanup.1", true);
+SpecialPowers.setBoolPref("simpletest.cleanup.2", true);
+SimpleTest.registerCleanupFunction(do_cleanup1);
+SimpleTest.registerCleanupFunction(do_cleanup2);
+ok(true, "dummy check");
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanity_cleanup2.html b/testing/mochitest/tests/Harness_sanity/test_sanity_cleanup2.html
new file mode 100644
index 0000000000..b0b7523819
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanity_cleanup2.html
@@ -0,0 +1,24 @@
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>SimpleTest.registerCleanupFunction test</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script class="testbody" type="text/javascript">
+for (const pref of [1, 2]) {
+  try {
+    SpecialPowers.getBoolPref("simpletest.cleanup." + pref);
+    ok(false, "Cleanup function should have unset pref");
+  }
+  catch(ex) {
+    ok(true, "Pref was not set");
+  }
+}
+
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanity_manifest.html b/testing/mochitest/tests/Harness_sanity/test_sanity_manifest.html
new file mode 100644
index 0000000000..d07df21ef5
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanity_manifest.html
@@ -0,0 +1,16 @@
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>SimpleTest.expected = 'fail' test</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script class="testbody" type="text/javascript">
+ok(false, "We expect this to fail");
+
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanity_manifest_pf.html b/testing/mochitest/tests/Harness_sanity/test_sanity_manifest_pf.html
new file mode 100644
index 0000000000..4b83fda596
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanity_manifest_pf.html
@@ -0,0 +1,17 @@
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>SimpleTest.expected = 'fail' test</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script class="testbody" type="text/javascript">
+ok(true, "We expect this to pass");
+ok(false, "We expect this to fail");
+
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/test_sanity_waitForCondition.html b/testing/mochitest/tests/Harness_sanity/test_sanity_waitForCondition.html
new file mode 100644
index 0000000000..f059adb88d
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/test_sanity_waitForCondition.html
@@ -0,0 +1,51 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="UTF-8">
+  <title>SimpleTest.waitForCondition test</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css">
+</head>
+<body>
+<script>
+
+var captureFailure = false;
+var capturedFailures = [];
+window.ok = function (cond, name) {
+  if (!captureFailure) {
+    SimpleTest.ok(cond, name);
+  } else if (cond) {
+      SimpleTest.ok(false, `Expect a failure with "${name}"`);
+    } else {
+      capturedFailures.push(name);
+    }
+};
+
+SimpleTest.waitForExplicitFinish();
+SimpleTest.requestFlakyTimeout("test behavior SimpleTest.waitForCondition");
+
+addLoadEvent(testNormal);
+
+function testNormal() {
+  var condition = false;
+  SimpleTest.waitForCondition(() => condition, () => {
+    ok(condition, "Should only be called when condition is true");
+    SimpleTest.executeSoon(testTimeout);
+  }, "Shouldn't timeout");
+  setTimeout(() => { condition = true; }, 1000);
+}
+
+function testTimeout() {
+  captureFailure = true;
+  SimpleTest.waitForCondition(() => false, () => {
+    captureFailure = false;
+    is(capturedFailures.length, 1, "Should captured one failure");
+    is(capturedFailures[0], "Should timeout",
+       "Should capture the failure passed in");
+    SimpleTest.executeSoon(() => SimpleTest.finish());
+  }, "Should timeout");
+}
+
+</script>
+</body>
+</html>
diff --git a/testing/mochitest/tests/Harness_sanity/xpcshell.ini b/testing/mochitest/tests/Harness_sanity/xpcshell.ini
new file mode 100644
index 0000000000..f31b5a5f2c
--- /dev/null
+++ b/testing/mochitest/tests/Harness_sanity/xpcshell.ini
@@ -0,0 +1,2 @@
+[test_SpecialPowersSandbox.js]
+[test_SpecialPowersSpawn.js]
-- 
cgit v1.2.3