wip: add sql test for logical plan

Author: matthewgapp

datafusion/sql/src/planner.rs

@@ -67,7 +67,7 @@ pub trait ContextProvider {
         _name: &str,
         _schema: SchemaRef,
     ) -> Result<Arc<dyn TableSource>> {
-        not_impl_err!("Recursive CTE is not supported")
+        not_impl_err!("Recursive CTE is not implemented")
     }
 
     /// Getter for a UDF description

datafusion/sql/tests/sql_integration.rs

@@ -1403,6 +1403,35 @@ fn recursive_ctes() {
     );
 }
 
+#[test]
+fn recursive_ctes_enabled() {
+    let sql = "
+        WITH RECURSIVE numbers AS (
+              select 1 as n
+            UNION ALL
+              select n + 1 FROM numbers WHERE N < 10
+        )
+        select * from numbers;";
+
+    // manually setting up test here so that we can enable recursive ctes
+    let mut context = MockContextProvider::default();
+    context.options_mut().execution.enable_recursive_ctes = true;
+
+    let planner = SqlToRel::new_with_options(&context, ParserOptions::default());
+    let result = DFParser::parse_sql_with_dialect(sql, &GenericDialect {});
+    let mut ast = result.unwrap();
+
+    let plan = planner
+        .statement_to_plan(ast.pop_front().unwrap())
+        .expect("recursive cte plan creation failed");
+
+    assert_eq!(
+        format!("{plan:?}"),
+        "Projection: numbers.n
+        SubqueryAlias: numbers\n    RecursiveQuery: is_distinct=false\n      Projection: Int64(1) AS n\n        EmptyRelation\n      Projection: numbers.n + Int64(1)\n        Filter: numbers.n < Int64(10)\n          TableScan: numbers"
+    );
+}
+
 #[test]
 fn select_simple_aggregate_with_groupby_and_column_is_in_aggregate_and_groupby() {
     quick_test(
@@ -2696,6 +2725,12 @@ struct MockContextProvider {
     udafs: HashMap<String, Arc<AggregateUDF>>,
 }
 
+impl MockContextProvider {
+    fn options_mut(&mut self) -> &mut ConfigOptions {
+        &mut self.options
+    }
+}
+
 impl ContextProvider for MockContextProvider {
     fn get_table_source(&self, name: TableReference) -> Result<Arc<dyn TableSource>> {
         let schema = match name.table() {
@@ -2805,6 +2840,14 @@ impl ContextProvider for MockContextProvider {
     fn options(&self) -> &ConfigOptions {
         &self.options
     }
+
+    fn create_cte_work_table(
+        &self,
+        _name: &str,
+        schema: SchemaRef,
+    ) -> Result<Arc<dyn TableSource>> {
+        Ok(Arc::new(EmptyTable::new(schema)))
+    }
 }
 
 #[test]