--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/luan/modules/lucene/SupplementingConfig.java	Sun Jul 26 23:11:53 2020 -0600
@@ -0,0 +1,49 @@
+package luan.modules.lucene;
+
+import java.util.Map;
+import java.util.Collections;
+import org.apache.lucene.index.IndexWriterConfig;
+import org.apache.lucene.index.SnapshotDeletionPolicy;
+import org.apache.lucene.util.Version;
+import goodjava.lucene.queryparser.MultiFieldParser;
+import goodjava.lucene.api.MultiFieldParserConfig;
+import goodjava.lucene.api.MoreFieldInfo;
+import luan.LuanFunction;
+import luan.LuanTable;
+import luan.LuanCloner;
+import luan.LuanException;
+import luan.LuanRuntimeException;
+
+
+final class SupplementingConfig extends MultiFieldParserConfig {
+	private final LuanFunction supplementer;
+
+	SupplementingConfig(Version luceneVersion,MultiFieldParser mfp,LuanFunction supplementer) {
+		super(luceneVersion,mfp);
+		LuanCloner cloner = new LuanCloner(LuanCloner.Type.COMPLETE);
+		this.supplementer = (LuanFunction)cloner.get(supplementer);
+	}
+
+	public IndexWriterConfig newLuceneConfig() {
+		IndexWriterConfig luceneConfig = super.newLuceneConfig();
+		SnapshotDeletionPolicy snapshotDeletionPolicy = new SnapshotDeletionPolicy(luceneConfig.getIndexDeletionPolicy());
+		luceneConfig.setIndexDeletionPolicy(snapshotDeletionPolicy);
+		return luceneConfig;
+	}
+
+	public MoreFieldInfo getMoreFieldInfo(Map<String,Object> storedFields) {
+		if( supplementer == null )
+			return super.getMoreFieldInfo(storedFields);
+		try {
+			LuanTable tbl = LuceneIndex.toTable(supplementer.luan(),storedFields);
+			tbl = (LuanTable)supplementer.call(tbl);
+			if( tbl == null ) {
+				return super.getMoreFieldInfo(storedFields);
+			} else {
+				return new MoreFieldInfo(LuceneIndex.toLucene(tbl),Collections.emptyMap());
+			}
+		} catch(LuanException e) {
+			throw new LuanRuntimeException(e);
+		}
+	}
+}