1 files changed, 12 insertions, 1 deletions
diff --git a/container-search/src/main/java/com/yahoo/search/grouping/request/YearFunction.java b/container-search/src/main/java/com/yahoo/search/grouping/request/YearFunction.java
index 5bda8231929..737597a585c 100644
--- a/container-search/src/main/java/com/yahoo/search/grouping/request/YearFunction.java
+++ b/container-search/src/main/java/com/yahoo/search/grouping/request/YearFunction.java
@@ -8,6 +8,7 @@ import java.util.Arrays;
  * the full year (e.g. 2010) of the result of the argument.
  *
  * @author Simon Thoresen Hult
+ * @author bratseth
  */
 public class YearFunction extends FunctionNode {
 
@@ -17,6 +18,16 @@ public class YearFunction extends FunctionNode {
      * @param exp The expression to evaluate, must evaluate to a long.
      */
     public YearFunction(GroupingExpression exp) {
-        super("time.year", Arrays.asList(exp));
+        this(null, null, exp);
     }
+
+    private YearFunction(String label, Integer level, GroupingExpression exp) {
+        super("time.year", label, level, Arrays.asList(exp));
+    }
+
+    @Override
+    public YearFunction copy() {
+        return new YearFunction(getLabel(), getLevelOrNull(), getArg(0).copy());
+    }
+
 }