Bug 1448048. Restrict the window.Components shim to non-nightly-only to see whether sites actually use it. r=mccr8

MozReview-Commit-ID: 6W1nEyKGlER
2018-03-23 12:53:48 -04:00 · 2018-03-23 12:53:48 -04:00 · de9297b4bf
--- a/dom/base/nsGlobalWindowInner.cpp
+++ b/dom/base/nsGlobalWindowInner.cpp
@ -3026,7 +3026,15 @@ nsGlobalWindowInner::DoResolve(JSContext* aCx, JS::Handle<JSObject*> aObj,
  // We support a cut-down Components.interfaces in case websites are
  // using Components.interfaces.nsIFoo.CONSTANT_NAME for the ones
  // that have constants.
-  if (aId == XPCJSRuntime::Get()->GetStringID(XPCJSContext::IDX_COMPONENTS)) {
+  static bool watchingComponentsPref = false;
+  static bool useComponentsShim = false;
+  if (!watchingComponentsPref) {
+    watchingComponentsPref = true;
+    Preferences::AddBoolVarCache(&useComponentsShim, "dom.use_components_shim",
+                                 true);
+  }
+  if (useComponentsShim &&
+      aId == XPCJSRuntime::Get()->GetStringID(XPCJSContext::IDX_COMPONENTS)) {
    return ResolveComponentsShim(aCx, aObj, aDesc);
  }

--- a/dom/events/test/test_bug238987.html
+++ b/dom/events/test/test_bug238987.html
@ -60,7 +60,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=238987
    if ("id" in e.target) {
      s = s + ", id=\"" + e.target.id + "\"";
    }
-    ok(e.eventPhase == Components.interfaces.nsIDOMEvent.CAPTURING_PHASE,
+    ok(e.eventPhase == Event.CAPTURING_PHASE,
       "|window| should not have got a focus event, " + s);
  }

@ -86,7 +86,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=238987
    if ("id" in e.target) {
      s = s + ", id=\"" + e.target.id + "\"";
    }
-    ok(e.eventPhase == Components.interfaces.nsIDOMEvent.CAPTURING_PHASE,
+    ok(e.eventPhase == Event.CAPTURING_PHASE,
       "|window| should not have got a blur event, " + s);
  }

--- a/dom/indexedDB/test/helpers.js
+++ b/dom/indexedDB/test/helpers.js
@ -16,7 +16,7 @@ var testGenerator = testSteps();
 // placebo for compat. An easy way to differentiate this from the real thing
 // is whether the property is read-only or not.
 var c = Object.getOwnPropertyDescriptor(this, "Components");
-if ((!c.value || c.writable) && typeof SpecialPowers === "object") {
+if ((!c || !c.value || c.writable) && typeof SpecialPowers === "object") {
  // eslint-disable-next-line no-native-reassign
  Components = SpecialPowers.Components;
 }
--- a/js/xpconnect/tests/chrome/test_bug795275.xul
+++ b/js/xpconnect/tests/chrome/test_bug795275.xul
@ -20,7 +20,10 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=795275
  /** Test for Warning in content scopes about Components. **/

  SimpleTest.waitForExplicitFinish();
-  SimpleTest.executeSoon(startLoad);
+  SimpleTest.executeSoon(function() {
+    SpecialPowers.pushPrefEnv({set: [["dom.use_components_shim", true]]},
+			      startLoad)
+  });
  function startLoad() {
    for (var i = 1; i <= document.getElementsByTagName('iframe').length; ++i) {
      var frame = document.getElementById('frame' + i);
--- a/js/xpconnect/tests/mochitest/mochitest.ini
+++ b/js/xpconnect/tests/mochitest/mochitest.ini
@ -95,6 +95,7 @@ support-files =
 [test_bug1005806.html]
 [test_bug1094930.html]
 [test_bug1158558.html]
+[test_bug1448048.html]
 [test_crosscompartment_weakmap.html]
 [test_frameWrapping.html]
 # The JS test component we use below is only available in debug builds.
--- a/js/xpconnect/tests/mochitest/test_bug1448048.html
+++ b/js/xpconnect/tests/mochitest/test_bug1448048.html
@ -0,0 +1,31 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1448048
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 1448048</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+  <script type="application/javascript">
+
+    /** Test for Bug 1448048 **/
+    var {AppConstants} = SpecialPowers.Cu.import("resource://gre/modules/AppConstants.jsm", {});
+    if (AppConstants.NIGHTLY_BUILD) {
+      is(typeof Components, "undefined", "Should be no Components shim on Nightly");
+    } else {
+      is(typeof Components, "object", "Should have a components shim on non-Nightly");
+    }
+  </script>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1448048">Mozilla Bug 1448048</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+</pre>
+</body>
+</html>
--- a/js/xpconnect/tests/mochitest/test_bug790732.html
+++ b/js/xpconnect/tests/mochitest/test_bug790732.html
@ -9,6 +9,10 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=790732
  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
  <script type="application/javascript">
+SimpleTest.waitForExplicitFinish();
+
+async function doTest() {
+  await SpecialPowers.pushPrefEnv({set: [["dom.use_components_shim", true]]})

  // Basic stuff
  ok(Components, "Components shim exists!");
@ -38,6 +42,11 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=790732
  is(Ci.nsIDOMRange, Range);
  is(Ci.nsIDOMNodeFilter, NodeFilter);
  is(Ci.nsIDOMXPathResult, XPathResult);
+
+  SimpleTest.finish();
+}
+
+doTest();
  </script>
 </head>
 <body>
--- a/mobile/android/tests/browser/robocop/robocop_head.js
+++ b/mobile/android/tests/browser/robocop/robocop_head.js
@ -14,7 +14,7 @@
 // is whether the property is read-only or not.
 {
  let c = Object.getOwnPropertyDescriptor(this, "Components");
-  if ((!c.value || c.writable) && typeof SpecialPowers === "object")
+  if ((!c || !c.value || c.writable) && typeof SpecialPowers === "object")
    Components = SpecialPowers.wrap(SpecialPowers.Components);
 }

--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@ -1386,6 +1386,13 @@ pref("dom.input.skip_cursor_move_for_same_value_set", true);

 pref("dom.cycle_collector.incremental", true);

+// Whether to shim a Components object on untrusted windows.
+#ifdef NIGHTLY_BUILD
+pref("dom.use_components_shim", false);
+#else // NIGHTLY_BUILD
+pref("dom.use_components_shim", true);
+#endif // NIGHTLY_BUILD
+
 // Parsing perf prefs. For now just mimic what the old code did.
 #ifndef XP_WIN
 pref("content.sink.pending_event_mode", 0);
--- a/testing/marionette/harness/marionette_harness/tests/unit/test_execute_script.py
+++ b/testing/marionette/harness/marionette_harness/tests/unit/test_execute_script.py
@ -268,7 +268,7 @@ class TestExecuteContent(MarionetteTestCase):
            exists = send("return typeof {} != 'undefined'".format(property))
            self.assertTrue(exists, "property {} is undefined".format(property))

-        self.assertTrue(send("return typeof Components.utils == 'undefined'"))
+        self.assertTrue(send("return (typeof Components == 'undefined') || (typeof Components.utils == 'undefined')"))
        self.assertTrue(send("return typeof window.wrappedJSObject == 'undefined'"))

    def test_no_callback(self):
--- a/testing/mochitest/tests/SimpleTest/EventUtils.js
+++ b/testing/mochitest/tests/SimpleTest/EventUtils.js
@ -28,22 +28,24 @@
 // be careful about our access to Components.interfaces. We also want to avoid
 // naming collisions with anything that might be defined in the scope that imports
 // this script.
+//
+// Even if the real |Components| doesn't exist, we might shim in a simple JS
+// placebo for compat. An easy way to differentiate this from the real thing
+// is whether the property is read-only or not.  The real |Components| property
+// is read-only.
 window.__defineGetter__('_EU_Ci', function() {
-  // Even if the real |Components| doesn't exist, we might shim in a simple JS
-  // placebo for compat. An easy way to differentiate this from the real thing
-  // is whether the property is read-only or not.
  var c = Object.getOwnPropertyDescriptor(window, 'Components');
-  return c.value && !c.writable ? Ci : SpecialPowers.Ci;
+  return c && c.value && !c.writable ? Ci : SpecialPowers.Ci;
 });

 window.__defineGetter__('_EU_Cc', function() {
  var c = Object.getOwnPropertyDescriptor(window, 'Components');
-  return c.value && !c.writable ? Cc : SpecialPowers.Cc;
+  return c && c.value && !c.writable ? Cc : SpecialPowers.Cc;
 });

 window.__defineGetter__('_EU_Cu', function() {
  var c = Object.getOwnPropertyDescriptor(window, 'Components');
-  return c.value && !c.writable ? Cu : SpecialPowers.Cu;
+  return c && c.value && !c.writable ? Cu : SpecialPowers.Cu;
 });

 window.__defineGetter__("_EU_OS", function() {
@ -119,12 +121,12 @@ function _EU_maybeWrap(o) {
    return o;
  }
  var c = Object.getOwnPropertyDescriptor(window, 'Components');
-  return c.value && !c.writable ? o : SpecialPowers.wrap(o);
+  return c && c.value && !c.writable ? o : SpecialPowers.wrap(o);
 }

 function _EU_maybeUnwrap(o) {
  var c = Object.getOwnPropertyDescriptor(window, 'Components');
-  return c.value && !c.writable ? o : SpecialPowers.unwrap(o);
+  return c && c.value && !c.writable ? o : SpecialPowers.unwrap(o);
 }

 /**
@ -2361,9 +2363,7 @@ function synthesizeDragStart(element, expectedDragData, aWindow, x, y)
  var trapDrag = function(event) {
    try {
      // We must wrap only in plain mochitests, not chrome
-      var c = Object.getOwnPropertyDescriptor(window, 'Components');
-      var dataTransfer = c.value && !c.writable
-        ? event.dataTransfer : SpecialPowers.wrap(event.dataTransfer);
+      var dataTransfer = _EU_maybeWrap(event.dataTransfer);
      result = null;
      if (!dataTransfer)
        throw "no dataTransfer";
--- a/testing/mochitest/tests/SimpleTest/SimpleTest.js
+++ b/testing/mochitest/tests/SimpleTest/SimpleTest.js
@ -865,10 +865,20 @@ SimpleTest.waitForFocus = function (callback, targetWindow, expectBlankPage) {

    // If this is a request to focus a remote child window, the request must
    // be forwarded to the child process.
-    // XXXndeakin now sure what this issue with Components.utils is about, but
-    // browser tests require the former and plain tests require the latter.
-    var Cu = Components.utils || SpecialPowers.Cu;
-    var Ci = Components.interfaces || SpecialPowers.Ci;
+    //
+    // Even if the real |Components| doesn't exist, we might shim in a simple JS
+    // placebo for compat. An easy way to differentiate this from the real thing
+    // is whether the property is read-only or not.  The real |Components|
+    // property is read-only.
+    var c = Object.getOwnPropertyDescriptor(window, 'Components');
+    var Cu, Ci;
+    if (c && c.value && !c.writable) {
+        Cu = Components.utils;
+        Ci = Components.interfaces;
+    } else {
+        Cu = SpecialPowers.Cu;
+        Ci = SpecialPowers.Ci;
+    }

    var browser = null;
    if (typeof(XULElement) != "undefined" &&