assertEquals(customEngine, scriptEngineFactory.getScriptEngine("customscriptengine"));
    }

    // Test add with overwriting existing engine
    public void test_add_overwriteExisting() {
        TestScriptEngine engine1 = new TestScriptEngine("first");
        TestScriptEngine engine2 = new TestScriptEngine("second");

        scriptEngineFactory.add("test", engine1);