more tests

qa/multi-cluster-search/src/test/java/org/elasticsearch/search/CCSDuelIT.java

@@ -43,6 +43,7 @@
 import org.elasticsearch.rest.action.search.RestSearchAction;
 import org.elasticsearch.script.Script;
 import org.elasticsearch.script.ScriptType;
+import org.elasticsearch.search.aggregations.AggregationBuilders;
 import org.elasticsearch.search.aggregations.BucketOrder;
 import org.elasticsearch.search.aggregations.bucket.filter.FilterAggregationBuilder;
 import org.elasticsearch.search.aggregations.bucket.histogram.DateHistogramAggregationBuilder;
@@ -580,13 +581,14 @@ public void testSortByField() throws Exception {
 
     public void testSortByFieldOneClusterHasNoResults() throws Exception {
         assumeMultiClusterSetup();
-        // set to a value greater than the number of shards to avoid differences due to the skipping of shards
+        // setting aggs to avoid differences due to the skipping of shards when matching none
         SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
         boolean onlyRemote = randomBoolean();
         sourceBuilder.query(new TermQueryBuilder("_index", onlyRemote ? REMOTE_INDEX_NAME : INDEX_NAME));
         sourceBuilder.sort("type.keyword", SortOrder.ASC);
         sourceBuilder.sort("creationDate", SortOrder.DESC);
         sourceBuilder.sort("user.keyword", SortOrder.ASC);
+        sourceBuilder.aggregation(AggregationBuilders.max("max").field("creationDate"));
         CheckedConsumer<ObjectPath, IOException> responseChecker = response -> {
             assertHits(response);
             int size = response.evaluateArraySize("hits.hits");