assertEquals("MyNonExistentEngine is not found.", e.getMessage());
        }
    }

    // Test engine replacement by class name
    @Test
    public void test_add_replacementByClassName() {
        TestScriptEngine engine1 = new TestScriptEngine("first");
        TestScriptEngine engine2 = new TestScriptEngine("second");

        scriptEngineFactory.add("name1", engine1);