@Test
public void lifecycleStartStartsItemAppender() {

    // given
    ItemSourceAppender mockItemAppender = mock(ItemSourceAppender.class);
    ItemAppenderFactory itemAppenderFactory = new ItemAppenderFactory() {
        @Override
        public ItemSourceAppender createInstance(boolean messageOnly, Layout layout, BatchDelivery batchDelivery) {
            return mockItemAppender;
        }
    };
    TestElasticsearchAppender appender = createTestElasticsearchAppender(itemAppenderFactory);
    // when
    appender.start();
    // then
    verify(mockItemAppender).start();
}