public IndexingResults bulkIndex(final List<MessageWithIndex> messageList) {
        return bulkIndex(messageList, false, null);
    }
@Test
    public void bulkIndexingShouldNotDoAnythingForEmptyList() throws Exception {
        final IndexingResults indexingResults = messages.bulkIndex(Collections.emptyList());

        assertThat(indexingResults).isNotNull();
        assertThat(indexingResults.allResults()).isEmpty();

        verify(messagesAdapter, never()).bulkIndex(any());
    }