'FIRESTORE INTERNAL ASSERTION FAILED: Unexpected state' when unit testing with Jest

Question

I'ḿ setting up a jest test suite for a Node.js and Express REST API i'm building, i'm using @firebase/testing module to initialize a testing app, however when i try to perform any sort of operation to the database this error comes out:

FIRESTORE (7.17.2) INTERNAL ASSERTION FAILED: Unexpected state
      at fail (/home/cardonapablo/Documentos/Proyectos/Optica (Ilicit)../../../../../node_modules/@firebase/testing/node_modules/@firebase/firestore/src/util/assert.ts:39:9)
      at hardAssert (/home/cardonapablo/Documentos/Proyectos/Optica (Ilicit)../../../../../node_modules/@firebase/testing/node_modules/@firebase/firestore/src/util/assert.ts:53:5)
      at fromBytes (/home/cardonapablo/Documentos/Proyectos/Optica (Ilicit)../../../../../node_modules/@firebase/testing/node_modules/@firebase/firestore/src/remote/serializer.ts:270:5)
      at fromWatchChange (/home/cardonapablo/Documentos/Proyectos/Optica (Ilicit)../../../../../node_modules/@firebase/testing/node_modules/@firebase/firestore/src/remote/serializer.ts:486:25)
      at PersistentListenStream.onMessage (/home/cardonapablo/Documentos/Proyectos/Optica (Ilicit)../../../../../node_modules/@firebase/testing/node_modules/@firebase/firestore/src/remote/persistent_stream.ts:576:25)
      at /home/cardonapablo/Documentos/Proyectos/Optica (Ilicit)../../../../../node_modules/@firebase/testing/node_modules/@firebase/firestore/src/remote/persistent_stream.ts:456:21
      at /home/cardonapablo/Documentos/Proyectos/Optica (Ilicit)../../../../../node_modules/@firebase/testing/node_modules/@firebase/firestore/src/remote/persistent_stream.ts:509:18
      at /home/cardonapablo/Documentos/Proyectos/Optica (Ilicit)../../../../../node_modules/@firebase/testing/node_modules/@firebase/firestore/src/util/async_queue.ts:369:14

I also tried connecting to my regular firestore database with the credentials i have been using to develop the endpoints and same error pops out even tho it's the app i use daily

Weird thing is, data is being written to the database, but error still stops testing

Here is firebase setup:

(src/db/functions.js)

let app  = initializeTestApp({ 
    projectId: "illicit"
})
db = app.firestore()
module.exports = { db }

Function throwing the error

(tests/fixtures/db.js)

const { db } = require('../../src/db/functions')
const bcrypt = require('bcrypt');

const createAdmin = async function() {

    // Encrypt password
    let encPass = await bcrypt.hash("admin", 8)

    let admin = {
        name: "Admin Test User",
        email: "[email protected]",
        password: encPass,
        tokens: []
    }

    // Add to db
    let docRef = await db.collection('admins').add(admin) // <- This line throws the error
    return;
}

module.exports = {
    createAdmin
}

And finally testing file

(tests/glasses.test.js)
const supertest = require('supertest');
const app = require('../src/app')
const functions = require('./fixtures/db')

let adminToken;
let glassesId;

//Executes before any test, here is where error occurs, before any tests
beforeAll( async () => {
    await functions.createAdmin()
    return
})

test('Should log in an admin', async () => {
    let response = await supertest(app)
    .post('/admins/login')
    .send({
        email: '[email protected]',
        password: 'admin'
    })
    .expect(200);
    expect(response.body.token).toEqual(expect.any(String))
    adminToken = response.token;
});

This only happens only when i try to test, regular app works just fine

Things i've tried:

• Firestore rules are read and write true, so it's not a rules error
• Mocked Firestore with firebase-mock and Jest seems to work fine, however this is not a solution, since i need to test data inside the database

Hope you can help me :)

Answer 1

You should change Jest's test environment from the default jsdom to node using jest --env=node or by setting the testEnvironment option to node in your Jest config.