Support ALTER POLICY statement

Author: nene

src/cst/AlterAction.ts

@@ -163,6 +163,8 @@ export type AlterTriggerAction =
   | AlterActionDependsOnExtension
   | AlterActionNoDependsOnExtension;
 
+export type AlterPolicyAction = AlterActionRename;
+
 export interface AlterActionRename extends BaseNode {
   type: "alter_action_rename";
   renameKw: Keyword<"RENAME"> | [Keyword<"RENAME">, Keyword<"TO" | "AS">];

src/cst/Policy.ts

@@ -1,10 +1,14 @@
+import { AlterPolicyAction } from "./AlterAction";
 import { BaseNode, Keyword } from "./Base";
 import { Grantee } from "./Dcl";
 import { Identifier, EntityName, Expr, ParenExpr, ListExpr } from "./Expr";
 
 export type AllPolicyNodes = AllPolicyStatements | CreatePolicyClause;
 
-export type AllPolicyStatements = CreatePolicyStmt | DropPolicyStmt;
+export type AllPolicyStatements =
+  | CreatePolicyStmt
+  | AlterPolicyStmt
+  | DropPolicyStmt;
 
 // CREATE POLICY name ON table
 export interface CreatePolicyStmt extends BaseNode {
@@ -61,6 +65,20 @@ export interface PolicyCheckClause extends BaseNode {
   expr: ParenExpr<Expr>;
 }
 
+export interface AlterPolicyStmt extends BaseNode {
+  type: "alter_policy_stmt";
+  alterPolicyKw: [Keyword<"ALTER">, Keyword<"POLICY">];
+  name: Identifier;
+  onKw: Keyword<"ON">;
+  table: EntityName;
+  actions: (
+    | AlterPolicyAction
+    | PolicyRolesClause
+    | PolicyUsingClause
+    | PolicyCheckClause
+  )[];
+}
+
 export interface DropPolicyStmt extends BaseNode {
   type: "drop_policy_stmt";
   dropPolicyKw: [Keyword<"DROP">, Keyword<"POLICY">];

src/parser.pegjs

@@ -171,6 +171,7 @@ ddl_statement_postgres
   / set_role_stmt
   / reset_role_stmt
   / create_policy_stmt
+  / alter_policy_stmt
   / drop_policy_stmt
 
 dml_statement
@@ -4704,6 +4705,24 @@ policy_check_clause
     return loc({ type: "policy_check_clause", withKw: read(withKw), checkKw: read(checkKw), expr });
   }
 
+alter_policy_stmt
+  = kw:(ALTER __ POLICY __) name:(ident __) onKw:(ON __) table:entity_name actions:(__ alter_policy_action)+ {
+    return loc({
+      type: "alter_policy_stmt",
+      alterPolicyKw: read(kw),
+      name: read(name),
+      onKw: read(onKw),
+      table,
+      actions: actions.map(read),
+    });
+  }
+
+alter_policy_action
+  = alter_action_rename
+  / policy_roles_clause
+  / policy_using_clause
+  / policy_check_clause
+
 drop_policy_stmt
   = kw:(DROP __ POLICY __) ifExistsKw:(if_exists __)? name:(ident __) onKw:(ON __) table:entity_name behaviorKw:(__ (CASCADE / RESTRICT))? {
     return loc({

src/showNode/policy.ts

@@ -15,6 +15,10 @@ export const policyMap: FullTransformMap<string, AllPolicyNodes> = {
   policy_using_clause: (node) => show([node.usingKw, node.expr]),
   policy_check_clause: (node) => show([node.withKw, node.checkKw, node.expr]),
 
+  // ALTER POLICY
+  alter_policy_stmt: (node) =>
+    show([node.alterPolicyKw, node.name, node.onKw, node.table, node.actions]),
+
   // DROP POLICY
   drop_policy_stmt: (node) =>
     show([

test/ddl/policy.test.ts

@@ -48,8 +48,41 @@ describe("policy", () => {
       });
     });
 
+    describe("ALTER POLICY", () => {
+      it("supports ALTER POLICY .. RENAME TO", () => {
+        testWc("ALTER POLICY foo ON my_table RENAME TO bar");
+        testWc("ALTER POLICY foo ON my_schema.my_table RENAME TO bar");
+      });
+
+      it("supports ALTER POLICY .. TO role", () => {
+        testWc("ALTER POLICY foo ON my_table TO my_role");
+        testWc("ALTER POLICY foo ON my_table TO PUBLIC");
+        testWc("ALTER POLICY foo ON my_table TO CURRENT_USER");
+        testWc("ALTER POLICY foo ON my_table TO CURRENT_ROLE");
+        testWc("ALTER POLICY foo ON my_table TO SESSION_USER");
+        testWc("ALTER POLICY foo ON my_table TO bar, baz, SESSION_USER");
+      });
+
+      it("supports ALTER POLICY .. USING ()", () => {
+        testWc("ALTER POLICY foo ON my_table USING (age > 10)");
+      });
+
+      it("supports ALTER POLICY .. WITH CHECK ()", () => {
+        testWc("ALTER POLICY foo ON my_table WITH CHECK (name <> '')");
+      });
+
+      it("supports combination of ALTER POLICY-s", () => {
+        testWc(`
+          ALTER POLICY foo ON my_table
+          TO my_role
+          USING (age > 10)
+          WITH CHECK (FALSE)
+        `);
+      });
+    });
+
     describe("DROP POLICY", () => {
-      it("supports CREATE POLICY .. ON ..", () => {
+      it("supports DROP POLICY .. ON ..", () => {
         testWc("DROP POLICY foo ON my_table");
         testWc("DROP POLICY foo ON my_schema.my_table");
       });