test: cover recursive CTE operators and errors

Author: KKould

src/planner/operator/mod.rs

@@ -921,6 +921,35 @@ mod tests {
         Ok(())
     }
 
+    #[cfg(feature = "spill")]
+    #[test]
+    fn recursive_operators_visit_display_and_build() -> Result<(), DatabaseError> {
+        let table_arena = TableArenaCell::default();
+        let mut arena = PlanArena::new(&table_arena);
+        let value = column("value", &mut arena);
+        let depth = column("depth", &mut arena);
+        let schema = vec![value, depth];
+
+        let recursive_cte = Operator::RecursiveCte(RecursiveCteOperator {
+            schema_ref: schema.clone(),
+        });
+        assert_eq!(referenced_columns(&recursive_cte, &mut arena)?, schema);
+        assert_eq!(recursive_cte.to_string(), "Recursive CTE: [#0, #1]");
+
+        let recursive_scan = Operator::RecursiveScan(RecursiveScanOperator {
+            schema_ref: schema.clone(),
+        });
+        assert_eq!(referenced_columns(&recursive_scan, &mut arena)?, schema);
+        assert_eq!(recursive_scan.to_string(), "Recursive Scan: [#0, #1]");
+
+        let anchor = LogicalPlan::new(Operator::ShowTable, Childrens::None);
+        let recursive = LogicalPlan::new(Operator::ShowView, Childrens::None);
+        let plan = RecursiveCteOperator::build(schema, anchor, recursive);
+        assert!(matches!(plan.operator, Operator::RecursiveCte(_)));
+        assert!(matches!(*plan.childrens, Childrens::Twins { .. }));
+        Ok(())
+    }
+
     #[test]
     fn mark_apply_constructors_and_accessors_cover_quantified_paths() {
         let left = LogicalPlan::new(Operator::ShowTable, Childrens::None);

tests/slt/cte.slt

@@ -186,3 +186,55 @@ WITH selected AS MATERIALIZED (
     SELECT id FROM cte_source
 )
 SELECT * FROM selected
+
+statement error
+WITH RECURSIVE first(x) AS (
+    SELECT 1 UNION ALL SELECT x FROM first
+), second(x) AS (
+    SELECT 1 UNION ALL SELECT x FROM second
+)
+SELECT * FROM first
+
+statement error
+WITH RECURSIVE recursive_cte(value) AS (
+    SELECT 1
+    UNION ALL
+    SELECT value FROM recursive_cte ORDER BY value
+)
+SELECT * FROM recursive_cte
+
+statement error
+WITH RECURSIVE cte_source(id, value) AS (
+    SELECT id, value FROM cte_source
+    UNION ALL
+    SELECT id, value FROM cte_source
+)
+SELECT * FROM cte_source
+
+statement error
+WITH RECURSIVE recursive_cte(value) AS (
+    SELECT 1
+    UNION ALL
+    SELECT 2
+)
+SELECT * FROM recursive_cte
+
+statement error
+WITH RECURSIVE recursive_cte(value) AS (
+    SELECT 1
+    UNION ALL
+    SELECT value, value FROM recursive_cte
+)
+SELECT * FROM recursive_cte
+
+statement error
+WITH RECURSIVE recursive_cte(value) AS (
+    SELECT 1
+    UNION ALL
+    SELECT 'value' FROM recursive_cte
+)
+SELECT * FROM recursive_cte
+
+statement error
+WITH selected AS (SELECT 1) FROM cte_source
+SELECT * FROM selected