### Question:
TupleToRange implements Function<Tuple2<String,IndexInfo>,Iterator<QueryPlan>> { public static boolean isDocumentRange(IndexInfo indexInfo) { return !indexInfo.uids().isEmpty(); } TupleToRange(JexlNode currentNode, ShardQueryConfiguration config); Iterator<QueryPlan> apply(Tuple2<String,IndexInfo> tuple); static boolean isDocumentRange(IndexInfo indexInfo); static boolean isShardRange(String shard); static Iterator<QueryPlan> createDocumentRanges(JexlNode queryNode, String shard, IndexInfo indexMatches, boolean isTldQuery); static Iterator<QueryPlan> createShardRange(JexlNode queryNode, String shard, IndexInfo indexInfo); static Iterator<QueryPlan> createDayRange(JexlNode queryNode, String shard, IndexInfo indexInfo);  }### Answer:
@Test public void testIsDocumentRange() { Set<String> docIds = Sets.newHashSet("docId0", "docId1", "docId2"); IndexInfo indexInfo = new IndexInfo(docIds); assertTrue(TupleToRange.isDocumentRange(indexInfo)); IndexInfo otherInfo = new IndexInfo(3L); assertFalse(TupleToRange.isDocumentRange(otherInfo)); }