diff -r 000000000000 -r 6474c204b198 toolkit/components/search/tests/xpcshell/test_invalid_engine_from_dir.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/components/search/tests/xpcshell/test_invalid_engine_from_dir.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,37 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+const Ci = Components.interfaces;
+
+/*
+ * Test that invalid engine files with xml extensions will not break
+ * initialization. See Bug 940446.
+ */
+function run_test() {
+  do_test_pending();
+
+  removeMetadata();
+  removeCacheFile();
+
+  do_check_false(Services.search.isInitialized);
+
+  let engineFile = gProfD.clone();
+  engineFile.append("searchplugins");
+  engineFile.append("test-search-engine.xml");
+  engineFile.parent.create(Ci.nsIFile.DIRECTORY_TYPE, FileUtils.PERMS_DIRECTORY);
+
+  // Copy the invalid engine to the test profile.
+  let engineTemplateFile = do_get_file("data/invalid-engine.xml");
+  engineTemplateFile.copyTo(engineFile.parent, "test-search-engine.xml");
+
+  Services.search.init(function search_initialized(aStatus) {
+    // The invalid engine should have been skipped and should not
+    // have caused an exception.
+    do_check_true(Components.isSuccessCode(aStatus));
+    do_check_true(Services.search.isInitialized);
+
+    removeMetadata();
+    removeCacheFile();
+    do_test_finished();
+  });
+}