diff -r 000000000000 -r 6474c204b198 toolkit/mozapps/extensions/test/xpcshell/test_bug576735.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_bug576735.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,66 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+// Tests that we recover gracefully from an extension directory disappearing
+// when we were expecting to uninstall it.
+
+var addon1 = {
+  id: "addon1@tests.mozilla.org",
+  version: "1.0",
+  name: "Test 1",
+  targetApplications: [{
+    id: "xpcshell@tests.mozilla.org",
+    minVersion: "1",
+    maxVersion: "1"
+  }]
+};
+
+var addon2 = {
+  id: "addon2@tests.mozilla.org",
+  version: "2.0",
+  name: "Test 2",
+  targetApplications: [{
+    id: "toolkit@mozilla.org",
+    minVersion: "1",
+    maxVersion: "1"
+  }]
+};
+
+const profileDir = gProfD.clone();
+profileDir.append("extensions");
+
+function run_test() {
+  do_test_pending();
+  createAppInfo("xpcshell@tests.mozilla.org", "XPCShell", "1", "2");
+
+  writeInstallRDFForExtension(addon1, profileDir);
+
+  startupManager();
+
+  AddonManager.getAddonByID("addon1@tests.mozilla.org", callback_soon(function(a1) {
+    a1.uninstall();
+
+    shutdownManager();
+
+    var dest = profileDir.clone();
+    dest.append(do_get_expected_addon_name("addon1@tests.mozilla.org"));
+    dest.remove(true);
+
+    writeInstallRDFForExtension(addon2, profileDir);
+
+    startupManager();
+
+    AddonManager.getAddonsByIDs(["addon1@tests.mozilla.org",
+                                 "addon2@tests.mozilla.org"],
+                                function([a1, a2]) {
+      // Addon1 should no longer be installed
+      do_check_eq(a1, null);
+
+      // Addon2 should have been detected
+      do_check_neq(a2, null);
+
+      do_execute_soon(do_test_finished);
+    });
+  }));
+}