Return the expected output

In if-else expressions, return the output of the executed branch
rather than the input. The current behavior was undocumented and
quite unexpected, so I suggest we treat that as a bug.

Also return the last executed expression in a script as its
output (rather than nothing.

In addition, improve some error messages.

1 files changed, 3 insertions, 1 deletions

diff --git a/config-model/src/main/java/com/yahoo/schema/processing/IndexingValidation.java b/config-model/src/main/java/com/yahoo/schema/processing/IndexingValidation.java
index 3c7e9b4066f..d2fb16264a0 100644
--- a/config-model/src/main/java/com/yahoo/schema/processing/IndexingValidation.java
+++ b/config-model/src/main/java/com/yahoo/schema/processing/IndexingValidation.java
@@ -24,6 +24,7 @@ import com.yahoo.vespa.indexinglanguage.expressions.SummaryExpression;
 import com.yahoo.vespa.indexinglanguage.expressions.VerificationContext;
 import com.yahoo.vespa.indexinglanguage.expressions.VerificationException;
 import com.yahoo.vespa.model.container.search.QueryProfiles;
+import com.yahoo.yolean.Exceptions;
 
 import java.util.HashSet;
 import java.util.Set;
@@ -51,7 +52,8 @@ public class IndexingValidation extends Processor {
                     converter.convert(exp); // TODO: stop doing this explicitly when visiting a script does not branch
                 }
             } catch (VerificationException e) {
-                fail(schema, field, "For expression '" + e.getExpression() + "': " + e.getMessage());
+                e.printStackTrace();
+                fail(schema, field, "For expression '" + e.getExpression() + "': " + Exceptions.toMessageString(e));
             }
         }
     }