giving an empty sorting spec should turn off sorting

2 files changed, 11 insertions, 2 deletions

diff --git a/container-search/src/main/java/com/yahoo/search/query/Ranking.java b/container-search/src/main/java/com/yahoo/search/query/Ranking.java
index 3c2a8a83c40..b1dd5624d18 100644
--- a/container-search/src/main/java/com/yahoo/search/query/Ranking.java
+++ b/container-search/src/main/java/com/yahoo/search/query/Ranking.java
@@ -233,7 +233,13 @@ public class Ranking implements Cloneable {
     public Sorting getSorting() { return sorting; }
 
     /** Sets how this query should be sorted. Set to null to turn off explicit sorting. */
-    public void setSorting(Sorting sorting) { this.sorting = sorting; }
+    public void setSorting(Sorting sorting) {
+        if (sorting == null || sorting.fieldOrders().isEmpty()) {
+            this.sorting = null;
+        } else {
+            this.sorting = sorting;
+        }
+    }
 
     /** Sets sorting from a string. See {@link Sorting} on syntax */
     public void setSorting(String sortingString) {
diff --git a/container-search/src/main/java/com/yahoo/search/ranking/GlobalPhaseRanker.java b/container-search/src/main/java/com/yahoo/search/ranking/GlobalPhaseRanker.java
index 91acc883803..1003cd942a8 100644
--- a/container-search/src/main/java/com/yahoo/search/ranking/GlobalPhaseRanker.java
+++ b/container-search/src/main/java/com/yahoo/search/ranking/GlobalPhaseRanker.java
@@ -37,7 +37,10 @@ public class GlobalPhaseRanker {
         var setup = globalPhaseSetupFor(query, schema).orElse(null);
         if (setup == null) return Optional.empty();
         var sorting = query.getRanking().getSorting();
-        if (sorting == null || sorting.fieldOrders() == null) return Optional.empty();
+        if (sorting == null) return Optional.empty();
+        if (sorting.fieldOrders() == null || sorting.fieldOrders().isEmpty()) {
+            return Optional.of(ErrorMessage.createIllegalQuery("Invalid sorting for global phase"));
+        }
         for (var fieldOrder : sorting.fieldOrders()) {
             if (!fieldOrder.getSorter().getName().equals("[rank]")
                     || fieldOrder.getSortOrder() != Sorting.Order.DESCENDING) {