Use doc values skipper for DateFieldType#isFieldWithinQuery

Author: jordan-powers

server/src/main/java/org/elasticsearch/index/mapper/DateFieldMapper.java

@@ -16,6 +16,7 @@
 import org.apache.lucene.document.LongPoint;
 import org.apache.lucene.document.SortedNumericDocValuesField;
 import org.apache.lucene.document.StoredField;
+import org.apache.lucene.index.DocValuesSkipper;
 import org.apache.lucene.index.IndexReader;
 import org.apache.lucene.index.LeafReaderContext;
 import org.apache.lucene.index.PointValues;
@@ -69,6 +70,7 @@
 import java.time.ZoneOffset;
 import java.time.ZonedDateTime;
 import java.util.Collections;
+import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
@@ -827,8 +829,24 @@ public Relation isFieldWithinQuery(
             QueryRewriteContext context
         ) throws IOException {
             if (isIndexed() == false && pointsMetadataAvailable == false && hasDocValues()) {
-                // we don't have a quick way to run this check on doc values, so fall back to default assuming we are within bounds
-                return Relation.INTERSECTS;
+                if (hasDocValuesSkipper() == false) {
+                    // we don't have a quick way to run this check on doc values, so fall back to default assuming we are within bounds
+                    return Relation.INTERSECTS;
+                }
+                long minValue = Long.MAX_VALUE;
+                long maxValue = Long.MIN_VALUE;
+                List<LeafReaderContext> leaves = reader.leaves();
+                if (leaves.size() == 0) {
+                    // no data, so nothing matches
+                    return Relation.DISJOINT;
+                }
+                for (LeafReaderContext ctx : leaves) {
+                    DocValuesSkipper skipper = ctx.reader().getDocValuesSkipper(name());
+                    assert skipper != null : "no skipper for field:" + name() + " and reader:" + reader;
+                    minValue = Long.min(minValue, skipper.minValue());
+                    maxValue = Long.max(maxValue, skipper.maxValue());
+                }
+                return isFieldWithinQuery(minValue, maxValue, from, to, includeLower, includeUpper, timeZone, dateParser, context);
             }
             byte[] minPackedValue = PointValues.getMinPackedValue(reader, name());
             if (minPackedValue == null) {