diff -r 4ebc2e2fb97c -r 71c04702a3d5 test/nashorn/script/basic/JDK-8026367.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/nashorn/script/basic/JDK-8026367.js	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * JDK-8026367: Add a sync keyword to mozilla_compat
+ *
+ * @test
+ * @run
+ */
+
+if (typeof sync === "undefined") {
+    load("nashorn:mozilla_compat.js");
+}
+
+var obj = {
+    count: 0,
+    // Sync called with one argument will synchronize on this-object of invocation
+    inc: sync(function(d) {
+        this.count += d;
+        Assert.assertTrue(java.lang.Thread.holdsLock(this));
+    }),
+    // Pass explicit object to synchronize on as second argument
+    dec: sync(function(d) {
+        this.count -= d;
+        Assert.assertTrue(java.lang.Thread.holdsLock(obj));
+    }, obj)
+};
+
+var t1 = new java.lang.Thread(function() {
+    for (var i = 0; i < 100000; i++) obj.inc(1);
+});
+var t2 = new java.lang.Thread(function() {
+    for (var i = 0; i < 100000; i++) obj.dec(1);
+});
+
+t1.start();
+t2.start();
+t1.join();
+t2.join();
+
+if (obj.count !== 0) {
+    throw new Error("Expected count == 0, got " + obj.count);
+}