Support PostgreSQL CYCLE clause in WITH

Author: nene

src/cst/Select.ts

@@ -11,7 +11,7 @@ import {
 } from "./Expr";
 import { Alias } from "./Alias";
 import { FrameClause } from "./WindowFrame";
-import { StringLiteral } from "./Literal";
+import { Literal, StringLiteral } from "./Literal";
 import { MysqlModifier } from "./dialects/Mysql";
 import { ColumnDefinition } from "./CreateTable";
 import { PostgresqlOperator, PostgresqlOperatorExpr } from "./Node";
@@ -22,6 +22,8 @@ export type AllSelectNodes =
   | WithClause
   | CommonTableExpr
   | CteSearchClause
+  | CteCycleClause
+  | CteCycleClauseValues
   | SelectClause
   | SelectAll
   | SelectDistinct
@@ -147,8 +149,10 @@ export interface CommonTableExpr extends BaseNode {
     | [Keyword<"NOT">, Keyword<"MATERIALIZED">];
   expr: ParenExpr<SubSelect>;
   search?: CteSearchClause;
+  cycle?: CteCycleClause;
 }
 
+// PostgreSQL
 export interface CteSearchClause extends BaseNode {
   type: "cte_search_clause";
   searchKw: [
@@ -162,6 +166,27 @@ export interface CteSearchClause extends BaseNode {
   resultColumn: Identifier;
 }
 
+// PostgreSQL
+export interface CteCycleClause extends BaseNode {
+  type: "cte_cycle_clause";
+  cycleKw: Keyword<"CYCLE">;
+  columns: ListExpr<Identifier>;
+  setKw: Keyword<"SET">;
+  resultColumn: Identifier;
+  values?: CteCycleClauseValues;
+  usingKw: Keyword<"USING">;
+  pathColumn: Identifier;
+}
+
+// PostgreSQL
+export interface CteCycleClauseValues extends BaseNode {
+  type: "cte_cycle_clause_values";
+  toKw: Keyword<"TO">;
+  markValue: Literal;
+  defaultKw?: Keyword<"DEFAULT">;
+  defaultValue: Literal;
+}
+
 export interface SelectClause extends BaseNode {
   type: "select_clause";
   selectKw: Keyword<"SELECT">;

src/parser.pegjs

@@ -192,7 +192,8 @@ common_table_expr
     asKw:(__ AS)
     materialized:(__ cte_materialized)?
     select:(__ paren$compound_select_stmt)
-    search:(__ cte_search_clause)? {
+    search:(__ cte_search_clause)?
+    cycle:(__ cte_cycle_clause)? {
       return loc({
         type: "common_table_expr",
         table: table,
@@ -201,6 +202,7 @@ common_table_expr
         materializedKw: read(materialized),
         expr: read(select),
         search: read(search),
+        cycle: read(cycle),
       });
     }
 
@@ -219,6 +221,33 @@ cte_search_clause
       });
     }
 
+cte_cycle_clause
+  = kw:(CYCLE __) columns:list$ident setKw:(__ SET __) resultColumn:ident
+    values:(__ cte_cycle_clause_values)?
+    usingKw:(__ USING __) pathColumn:ident &postgres {
+      return loc({
+        type: "cte_cycle_clause",
+        cycleKw: read(kw),
+        columns: columns,
+        setKw: read(setKw),
+        resultColumn: resultColumn,
+        values: read(values),
+        usingKw: read(usingKw),
+        pathColumn: pathColumn,
+      });
+    }
+
+cte_cycle_clause_values
+  = toKw:(TO __) markValue:literal defaultKw:(__ DEFAULT __) defaultValue:literal {
+    return loc({
+      type: "cte_cycle_clause_values",
+      toKw: read(toKw),
+      markValue: markValue,
+      defaultKw: read(defaultKw),
+      defaultValue: defaultValue,
+    });
+  }
+
 // Other clauses of SELECT statement (besides WITH & SELECT)
 other_clause
   = from_clause
@@ -5890,6 +5919,7 @@ CURRENT_SCHEMA      = kw:"CURRENT_SCHEMA"i      !ident_part { return loc(createK
 CURRENT_TIME        = kw:"CURRENT_TIME"i        !ident_part { return loc(createKeyword(kw)); }
 CURRENT_TIMESTAMP   = kw:"CURRENT_TIMESTAMP"i   !ident_part { return loc(createKeyword(kw)); }
 CURRENT_USER        = kw:"CURRENT_USER"i        !ident_part { return loc(createKeyword(kw)); }
+CYCLE               = kw:"CYCLE"i               !ident_part { return loc(createKeyword(kw)); }
 DATA                = kw:"DATA"i                !ident_part { return loc(createKeyword(kw)); }
 DATABASE            = kw:"DATABASE"i            !ident_part { return loc(createKeyword(kw)); }
 DATE                = kw:"DATE"i                !ident_part { return loc(createKeyword(kw)); }

src/showNode/select.ts

@@ -15,9 +15,22 @@ export const selectMap: FullTransformMap<string, AllSelectNodes> = {
       node.materializedKw,
       node.expr,
       node.search,
+      node.cycle,
     ]),
   cte_search_clause: (node) =>
     show([node.searchKw, node.columns, node.setKw, node.resultColumn]),
+  cte_cycle_clause: (node) =>
+    show([
+      node.cycleKw,
+      node.columns,
+      node.setKw,
+      node.resultColumn,
+      node.values,
+      node.usingKw,
+      node.pathColumn,
+    ]),
+  cte_cycle_clause_values: (node) =>
+    show([node.toKw, node.markValue, node.defaultKw, node.defaultValue]),
   // SELECT
   select_clause: (node) => show([node.selectKw, node.modifiers, node.columns]),
   select_all: (node) => show(node.allKw),

test/select/with.test.ts

@@ -42,5 +42,23 @@ describe("select WITH", () => {
         SELECT * FROM tree ORDER BY ordercol
       `);
     });
+
+    it("supports CYCLE clause", () => {
+      testWc(`
+        WITH RECURSIVE search_graph AS (
+          SELECT 1
+        ) CYCLE col1, col2 SET is_cycle USING path_col
+        SELECT * FROM search_graph
+      `);
+    });
+
+    it("supports CYCLE clause with TO..DEFAULT", () => {
+      testWc(`
+        WITH RECURSIVE search_graph AS (
+          SELECT 1
+        ) CYCLE col1 SET is_cycle TO true DEFAULT false USING path_col
+        SELECT * FROM search_graph
+      `);
+    });
   });
 });