For some DrillSideways searches I get NullPointerException.
I have tracked the problem to DrillSidewaysScorer class, on line 126 in DrillSidewaysScorer.java:
long baseQueryCost = baseScorer.cost();
On some of my index segments, this call throws NullPoinerException.
"baseScorer" is instance of ReqExclScorer.
public long cost()
throws NullPointerException because reqScorer is null.