feat(plpgsql-deparser): include full CREATE FUNCTION in hydrate demo

- Parse full SQL statement to get CREATE FUNCTION wrapper
- Modify function name: big_kitchen_sink -> big_kitchen_sink_MODIFIED
- Include RETURNS TABLE clause in snapshot
- Demonstrate full pipeline: SQL parse -> PL/pgSQL hydrate -> modify -> dehydrate -> SQL deparse

Author: pyramation

packages/plpgsql-deparser/__tests__/__snapshots__/hydrate-demo.test.ts.snap

@@ -1,7 +1,7 @@
 // Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
 
-exports[`hydrate demonstration with big-function.sql should parse, hydrate, modify, and deparse big-function.sql 1`] = `
-"DECLARE
+exports[`hydrate demonstration with big-function.sql should parse, hydrate, modify, and deparse big-function.sql with full CREATE FUNCTION 1`] = `
+"CREATE OR REPLACE FUNCTION app_public."big_kitchen_sink_MODIFIED"(p_org_id uuid, p_user_id uuid, p_from_ts timestamptz DEFAULT now() - '30 days'::interval, p_to_ts timestamptz DEFAULT now(), p_min_total numeric DEFAULT 0, p_max_rows int DEFAULT 250, p_currency text DEFAULT 'USD', p_apply_discount boolean DEFAULT true, p_discount_rate numeric DEFAULT 0.05, p_tax_rate numeric DEFAULT 0.0875, p_round_to int DEFAULT 2, p_note text DEFAULT NULL, p_lock boolean DEFAULT false, p_debug boolean DEFAULT false) RETURNS TABLE ( org_id uuid, user_id uuid, period_from timestamptz, period_to timestamptz, orders_scanned int, orders_upserted int, gross_total numeric, discount_total numeric, tax_total numeric, net_total numeric, avg_order_total numeric, top_sku text, top_sku_qty bigint, message text ) LANGUAGE plpgsql AS $$DECLARE
   v_orders_scanned int := 888;
   v_orders_upserted int := 888;
   v_gross numeric := 888;
@@ -167,5 +167,5 @@ END IF;
     RETURN;
 END;
   RETURN;
-END"
+END$$"
 `;

packages/plpgsql-deparser/__tests__/hydrate-demo.test.ts

@@ -1,4 +1,5 @@
-import { loadModule, parsePlPgSQLSync } from '@libpg-query/parser';
+import { loadModule, parsePlPgSQLSync, parseSync } from '@libpg-query/parser';
+import { deparse } from 'pgsql-deparser';
 import * as fs from 'fs';
 import * as path from 'path';
 import { hydratePlpgsqlAst, dehydratePlpgsqlAst, PLpgSQLParseResult, deparseSync } from '../src';
@@ -8,13 +9,23 @@ describe('hydrate demonstration with big-function.sql', () => {
     await loadModule();
   });
 
-  it('should parse, hydrate, modify, and deparse big-function.sql', () => {
+  it('should parse, hydrate, modify, and deparse big-function.sql with full CREATE FUNCTION', async () => {
     const fixturePath = path.join(__dirname, '../../../__fixtures__/plpgsql-pretty/big-function.sql');
     const sql = fs.readFileSync(fixturePath, 'utf-8');
 
-    const parsed = parsePlPgSQLSync(sql) as unknown as PLpgSQLParseResult;
+    const sqlParsed = parseSync(sql) as any;
+    const createFunctionStmt = sqlParsed.stmts[0].stmt.CreateFunctionStmt;
 
-    const { ast: hydratedAst, stats } = hydratePlpgsqlAst(parsed);
+    const asOption = createFunctionStmt.options.find(
+      (opt: any) => opt.DefElem?.defname === 'as'
+    );
+    const plpgsqlBody = asOption?.DefElem?.arg?.List?.items?.[0]?.String?.sval;
+    
+    expect(plpgsqlBody).toBeDefined();
+    
+    const plpgsqlParsed = parsePlPgSQLSync(sql) as unknown as PLpgSQLParseResult;
+    
+    const { ast: hydratedAst, stats } = hydratePlpgsqlAst(plpgsqlParsed);
 
     expect(stats.totalExpressions).toBe(68);
     expect(stats.parsedExpressions).toBe(68);
@@ -23,17 +34,28 @@ describe('hydrate demonstration with big-function.sql', () => {
     expect(stats.failedExpressions).toBe(0);
     expect(stats.rawExpressions).toBe(0);
 
-    const modifiedAst = modifyAst(JSON.parse(JSON.stringify(hydratedAst)));
+    createFunctionStmt.funcname[1].String.sval = 'big_kitchen_sink_MODIFIED';
+    
+    const modifiedPlpgsqlAst = modifyAst(JSON.parse(JSON.stringify(hydratedAst)));
 
-    const dehydratedAst = dehydratePlpgsqlAst(modifiedAst);
+    const dehydratedAst = dehydratePlpgsqlAst(modifiedPlpgsqlAst);
+    
+    const modifiedBody = deparseSync(dehydratedAst);
+    
+    if (asOption?.DefElem?.arg?.List?.items?.[0]?.String) {
+      asOption.DefElem.arg.List.items[0].String.sval = modifiedBody;
+    }
 
-    const deparsed = deparseSync(dehydratedAst);
+    const fullDeparsed = await deparse(sqlParsed.stmts[0].stmt);
 
-    expect(deparsed).toContain('v_discount_MODIFIED');
-    expect(deparsed).toContain('v_tax_MODIFIED');
-    expect(deparsed).toContain('888');
+    expect(fullDeparsed).toContain('big_kitchen_sink_MODIFIED');
+    expect(fullDeparsed).toContain('RETURNS TABLE');
+    expect(fullDeparsed).toContain('CREATE OR REPLACE FUNCTION');
+    expect(fullDeparsed).toContain('v_discount_MODIFIED');
+    expect(fullDeparsed).toContain('v_tax_MODIFIED');
+    expect(fullDeparsed).toContain('888');
 
-    expect(deparsed).toMatchSnapshot();
+    expect(fullDeparsed).toMatchSnapshot();
   });
 });