Hi, I am getting null pointer exception when streaming search is done with collapse filter query. When debugged the last element in FixedBitSet array is null. Please let me know if I can raise an issue.
https://github.com/apache/lucene-solr/blob/master/solr/core/src/java/org/apache/solr/handler/export/ExportWriter.java#L232 http://localhost:8983/stream/?expr=search(coll_a ,sort="field_a asc",fl="field_a,field_b,field_c,field_d",qt="/export",q="*:*",fq="(filed_b:x)",fq="{!collapse field=field_c sort='field_d desc'}") org.apache.solr.servlet.HttpSolrCall null:java.lang.NullPointerException at org.apache.lucene.util.BitSetIterator.<init>(BitSetIterator.java:61) at org.apache.solr.handler.ExportWriter.writeDocs(ExportWriter.java:243) at org.apache.solr.handler.ExportWriter.lambda$null$1(ExportWriter.java:222) at org.apache.solr.response.JSONWriter.writeIterator(JSONResponseWriter.java:523) at org.apache.solr.response.TextResponseWriter.writeVal(TextResponseWriter.java:180) at org.apache.solr.response.JSONWriter$2.put(JSONResponseWriter.java:559) at org.apache.solr.handler.ExportWriter.lambda$null$2(ExportWriter.java:222) at org.apache.solr.response.JSONWriter.writeMap(JSONResponseWriter.java:547) at org.apache.solr.response.TextResponseWriter.writeVal(TextResponseWriter.java:198) at org.apache.solr.response.JSONWriter$2.put(JSONResponseWriter.java:559) at org.apache.solr.handler.ExportWriter.lambda$write$3(ExportWriter.java:220) at org.apache.solr.response.JSONWriter.writeMap(JSONResponseWriter.java:547) at org.apache.solr.handler.ExportWriter.write(ExportWriter.java:218) at org.apache.solr.core.SolrCore$3.write(SolrCore.java:2627) at org.apache.solr.response.QueryResponseWriterUtil.writeQueryResponse(QueryResponseWriterUtil.java:49)
