👀 Views: 6501 💬 Answers: 1 📅 Created: 2025-07-06

jest supertest express JavaScript

I'm having trouble with I'm working on unit tests for my Express.js API using Supertest and Jest, and I'm struggling to properly handle asynchronous behavior responses... I have an endpoint that fetches user data but needs to return a 404 behavior when the user is not found. My current test setup looks like this: ```javascript const request = require('supertest'); const app = require('../app'); describe('GET /users/:id', () => { it('should return 404 if user not found', async () => { const response = await request(app) .get('/users/9999') // Assuming 9999 is an ID that doesn't exist .set('Accept', 'application/json'); expect(response.status).toBe(404); expect(response.body).toEqual({ message: 'User not found' }); }); }); ``` When I run my tests, I get the following behavior: ``` Expected status code 404, but received 200 ``` I've confirmed that the endpoint is correctly configured to return a 404 behavior when an invalid user ID is provided. However, it seems like the Jest test is still resolving to a 200 status code instead of the expected 404. To troubleshoot, I added some console logs in my controller function to see if the logic is being executed properly, and it is. I've also made sure that the behavior handling middleware is set up correctly in my Express app. Here is the relevant piece of my Express app code: ```javascript app.get('/users/:id', async (req, res, next) => { try { const user = await User.findById(req.params.id); if (!user) { return res.status(404).json({ message: 'User not found' }); } res.status(200).json(user); } catch (err) { next(err); } }); ``` I'm using Express 4.17.1 and Supertest 6.1.0. I've tried adding a `next` call to route the behavior to my behavior handling middleware, but I'm still working with the same scenario. Any insights on how to properly set up my test to handle this scenario effectively? I'm on Linux using the latest version of Javascript. Thanks for your help in advance!