YQL-19163 Fix StaticFold behavior with optional args lambdas

commit_hash:bbea0c78d15d9ba627f15182d80dd2406a494b93

1 files changed, 13 insertions, 1 deletions

diff --git a/yql/essentials/tests/sql/suites/expr/static_fold.sql b/yql/essentials/tests/sql/suites/expr/static_fold.sql
index 9118da0e06..81444ea9b3 100644
--- a/yql/essentials/tests/sql/suites/expr/static_fold.sql
+++ b/yql/essentials/tests/sql/suites/expr/static_fold.sql
@@ -18,4 +18,16 @@ SELECT
     StaticFold1($st_many, $start, $concat),
     StaticFold1($st_single, $start, $concat),
     CAST(StaticFold1($st_empty, $start, $concat) AS Optional<String>),
-    StaticFold1($tup, $start, $concat);
\ No newline at end of file
+    StaticFold1($tup, $start, $concat);
+
+--WithOptionalArgs lambda test
+$puk = ($row_struct) -> {
+    RETURN StaticFold(
+        $row_struct, 
+        0, 
+        ($item, $sum?) -> {
+            RETURN $sum + IF($item IS NULL, 0, 1)
+        }
+    )
+};
+SELECT $puk(Unwrap(CAST(<|one:"8912", two:42|> AS Struct<one: Int64, two:Int64>)));
\ No newline at end of file