Handle an existing spantree in exactmatch

This may happen if a field which is indexed is used as an input for another
field indexed as exact match.

2 files changed, 13 insertions, 6 deletions

diff --git a/indexinglanguage/src/main/java/com/yahoo/vespa/indexinglanguage/expressions/ExactExpression.java b/indexinglanguage/src/main/java/com/yahoo/vespa/indexinglanguage/expressions/ExactExpression.java
index 14b5af53b5a..31633cdc88b 100644
--- a/indexinglanguage/src/main/java/com/yahoo/vespa/indexinglanguage/expressions/ExactExpression.java
+++ b/indexinglanguage/src/main/java/com/yahoo/vespa/indexinglanguage/expressions/ExactExpression.java
@@ -27,24 +27,30 @@ public final class ExactExpression extends Expression {
     @Override
     protected void doExecute(ExecutionContext ctx) {
         StringFieldValue input = (StringFieldValue)ctx.getValue();
-        if (input.getString().isEmpty()) {
-            return;
-        }
+        if (input.getString().isEmpty()) return;
+
         StringFieldValue output = input.clone();
         ctx.setValue(output);
 
         String prev = output.getString();
         String next = toLowerCase(prev);
 
-        SpanList root = new SpanList();
-        SpanTree tree = new SpanTree(SpanTrees.LINGUISTICS, root);
+        SpanTree tree = output.getSpanTree(SpanTrees.LINGUISTICS);
+        SpanList root;
+        if (tree == null) {
+            root = new SpanList();
+            tree = new SpanTree(SpanTrees.LINGUISTICS, root);
+            output.setSpanTree(tree);
+        }
+        else {
+            root = (SpanList)tree.getRoot();
+        }
         SpanNode node = new Span(0, prev.length());
         tree.annotate(node, new Annotation(AnnotationTypes.TERM,
                                            next.equals(prev) ? null : new StringFieldValue(next)));
         tree.annotate(node, new Annotation(AnnotationTypes.TOKEN_TYPE,
                                            new IntegerFieldValue(TokenType.ALPHABETIC.getValue())));
         root.add(node);
-        output.setSpanTree(tree);
     }
 
     @Override
diff --git a/indexinglanguage/src/main/java/com/yahoo/vespa/indexinglanguage/expressions/FlattenExpression.java b/indexinglanguage/src/main/java/com/yahoo/vespa/indexinglanguage/expressions/FlattenExpression.java
index e43744420f8..91f46381def 100644
--- a/indexinglanguage/src/main/java/com/yahoo/vespa/indexinglanguage/expressions/FlattenExpression.java
+++ b/indexinglanguage/src/main/java/com/yahoo/vespa/indexinglanguage/expressions/FlattenExpression.java
@@ -24,6 +24,7 @@ public final class FlattenExpression extends Expression {
     public FlattenExpression() {
         super(DataType.STRING);
     }
+
     @Override
     protected void doExecute(ExecutionContext ctx) {
         StringFieldValue input = (StringFieldValue)ctx.getValue();