Sometimes Jest integration tests fails and sometimes don't when I run all the suites

Question

I've written some integration test using Jest, Supertest, Moongose. I run all test isolated (test.only) and they work but sometimes don't. Often this happens when I run the entire test suite. I give you an example: This test creates a new registry in a MongoDB collection and then other test use this new registry to perform another operations:

            beforeAll(async () => {
              await mongoose.connect(config.mongoose.url, config.mongoose.options);
            });
            
            afterAll(async () => {
              await mongoose.disconnect();
              await new Promise(resolve => setTimeout(() => resolve(), 500));
            });
            
            let credentials = [];
            let fechaHora = [];

            // generate a new Id registry
            // generate credentials
            // generate date and hour
            beforeEach(async () => {
                rooms.insertRoomsToFile(rooms.getNewIdRoom() + '|');
                _idRoom = rooms.getIdRoom();
                credentials = await rooms.generateCredentialsBE(_idOrganization, basicToken);
                fechaHora = rooms.generateRoomDateAndHour();
            });

            test(`endpoint ${BASE_URL}${registerMeetingRoute} : 200 OK (Happy Path)`, async () => {
                generatedIdRoom = _idRoom;
                const data = {
                    idOrganization: 1,
                    idRoom: generatedIdRoom,
                    date: fechaHora[0],
                    hour: fechaHora[1],
                    attendes: [
                        {
                            email: "[email protected]",
                            id: 1,
                            firstName: "John",
                            lastName: "Doe",
                            userAttende: "10000000-0000-0000-0000-000000000000",
                            rol: 1,
                            telephone: "5555555555"
                        },
                        {
                            email: "[email protected]",
                            id: 2,
                            firstName: "Tom",
                            lastName: "Taylor",
                            userAttende: "20000000-0000-0000-0000-000000000000",
                            rol: 2,
                            telephone: "5555555556"
                        }
                    ]
                };
                const encryptedData = await rooms.encrypt(data);
                idAccess = encryptedData.idAccess;
                await request(app)
                    .post(`${BASE_URL}${registerMeetingRoute}`)
                    .set('content-type', 'application/json')
                    .set('authorization', 'Bearer ' + credentials[2])
                    .set('x-accessId', idAccess)
                    .send(encryptedData)
                    .expect(200);

                    rooms.saveLog(JSON.stringify(encryptedData), `endpoint      ${BASE_URL}${registerMeetingRoute} : 200 OK (Happy Path)`);
            });

This works fine, the problem is sometimes don't. I've tried many answers here and read blogs about this topic but I can't solve it. I tried:

• Increase testTimeout property in jest.config.js
• Open and close MongoDb connection per test
• To use mongodb-memory-server
• --runInBand option

Thanks in advance :)

Chrissie

Answer 1

Jest will execute different test files in parallel and in a different order from run to run.

You can change this behaviour and write your own custom test sequencer.

Antilebanon

Answer 2

Jest will execute all tests within a single file sequentially. However, I've also encountered issues with the complete file run vs. running a single test, in case a plug-in a router with WebHashHistory into the wrapper mount. The problem does not occur with MemoryHistory:

const router = createRouter({
  history: createMemoryHistory(),
  routes: myRoutes,
})

Vue 3.2, Vue-router 4.0, vue-test-utils v2.0, options API, SFC, Jest v27.0

Hypochlorite