unit test fixes + error refactor

src/routes/flyer.routes.test.ts

@@ -5,6 +5,7 @@ import express, { Request, Response, NextFunction } from 'express';
 import { errorHandler } from '../middleware/errorHandler';
 import flyerRouter from './flyer.routes';
 import { createMockFlyer, createMockFlyerItem } from '../tests/utils/mockFactories';
+import { NotFoundError } from '../services/db/errors.db';
 
 // 1. Mock the Service Layer directly.
 vi.mock('../services/db/index.db', () => ({
@@ -78,8 +79,9 @@ describe('Flyer Routes (/api/flyers)', () => {
     });
 
     it('should return 404 if the flyer is not found', async () => {
-      vi.mocked(db.flyerRepo.getFlyerById).mockResolvedValue(undefined);
+      vi.mocked(db.flyerRepo.getFlyerById).mockRejectedValue(new NotFoundError('Flyer not found'));
       const response = await supertest(app).get('/api/flyers/999');
+
       expect(response.status).toBe(404);
       expect(response.body.message).toContain('not found');
     });