Parse generated tensor function trees

To make generated tensor function trees transparent to
the config model we need to convert each tensor function node
to the corresponding ranking expression node.
This is most easily done by parsing the tensor function
tree string output as a ranking expression (something
which is required to always work in any case).

1 files changed, 3 insertions, 1 deletions

diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/TensorFunctionNode.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/TensorFunctionNode.java
index 8af3448ca6f..b42570d3aea 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/TensorFunctionNode.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/TensorFunctionNode.java
@@ -139,7 +139,9 @@ public class TensorFunctionNode extends CompositeNode {
         final Deque<String> path;
         final CompositeNode parent;
 
-        public static final ExpressionNodeToStringContext empty = new ExpressionNodeToStringContext(null, null, null);
+        public static final ExpressionNodeToStringContext empty = new ExpressionNodeToStringContext(new SerializationContext(),
+                                                                                                    null,
+                                                                                                    null);
 
         public ExpressionNodeToStringContext(SerializationContext context, Deque<String> path, CompositeNode parent) {
             this.context = context;