@Test
public void testDeleteById_RetryIndividually() throws SolrServerException, IOException {

    String badId = "badId";
    String goodId = "goodId";
    List<String> idsToDelete = Lists.newArrayList(badId, goodId);
    
    when(solrServer.deleteById(idsToDelete)).thenThrow(new SolrException(ErrorCode.BAD_REQUEST, "bad id"));
    when(solrServer.deleteById(badId)).thenThrow(new SolrException(ErrorCode.BAD_REQUEST, "bad id"));
    
    solrWriter.deleteById(-1, idsToDelete);
    
    verify(solrServer).deleteById(goodId);
}