this error

Uncaught exception: Error: listen EADDRINUSE: address already in use :::3000

import supertest from "supertest"
import axios from "axios"
import app from ".."
const request = supertest(app)

describe("Test endpoint responses", () => {
    it("gets the api endpoint", async () => {
      const response = await request.get("/api/images")
       expect(response.ok).toBe(false)
    })
})

>Solution :

This means that the port 3000 of the machine that is executing the test is already used. As a general rule, a port cannot be used by multiple application at the same time.

In your case, you probably already have another test running, or a local development server running on this port.

You can either stop it, or configure your test runner to use a different port.

EDIT 1 :

As mentioned by chovy in comment, you can prepend your command with PORT=3001