Testing gen 2 cloud function using jest error

 FAIL  lib/functions/functions.test.js
  ● Test suite failed to run

    Your test suite must contain at least one test.

      at onResult (node_modules/@jest/core/build/TestScheduler.js:133:18)
      at node_modules/@jest/core/build/TestScheduler.js:254:19
      at node_modules/emittery/index.js:363:13
          at Array.map (<anonymous>)
      at Emittery.emit (node_modules/emittery/index.js:361:23)

 FAIL  lib/index.test.js
  ● Test suite failed to run

    The default Firebase app does not exist. Make sure you call initializeApp() before using any of the Firebase services.

      2 | import * as admin from 'firebase-admin';
      3 | // connect the firestore DB
    > 4 | const firestore = admin.firestore();
        |                         ^
      5 | // External Libraries
      6 | import * as CryptoJs from 'crypto-js';
      7 | // Types

      at AppStore.getApp (node_modules/firebase-admin/lib/app/lifecycle.js:65:19)
      at FirebaseNamespaceInternals.app (node_modules/firebase-admin/lib/app/firebase-namespace.js:54:35)
      at FirebaseNamespace.app (node_modules/firebase-admin/lib/app/firebase-namespace.js:256:30)
      at FirebaseNamespace.ensureApp (node_modules/firebase-admin/lib/app/firebase-namespace.js:266:24)
      at FirebaseNamespace.fn (node_modules/firebase-admin/lib/app/firebase-namespace.js:136:25)
      at Object.<anonymous> (src/functions/onCallFunctions.ts:4:25)
      at Object.<anonymous> (index.test.ts:4:1)

 FAIL  src/test/online.test.ts
  ● Test suite failed to run

    The default Firebase app does not exist. Make sure you call initializeApp() before using any of the Firebase services.

      1 | import * as admin from 'firebase-admin';
    > 2 | const firestore = admin.firestore();
        |                         ^
      3 |
      4 | // import * as functionsHttps from 'firebase-functions/v2/https';
      5 | import { onDocumentCreated } from 'firebase-functions/v2/firestore';

      at AppStore.getApp (node_modules/firebase-admin/lib/app/lifecycle.js:65:19)
      at FirebaseNamespaceInternals.app (node_modules/firebase-admin/lib/app/firebase-namespace.js:54:35)
      at FirebaseNamespace.app (node_modules/firebase-admin/lib/app/firebase-namespace.js:256:30)
      at FirebaseNamespace.ensureApp (node_modules/firebase-admin/lib/app/firebase-namespace.js:266:24)
      at FirebaseNamespace.fn (node_modules/firebase-admin/lib/app/firebase-namespace.js:136:25)
      at Object.<anonymous> (src/functions/v2cloudFunctions.ts:2:25)
      at Object.<anonymous> (src/test/online.test.ts:3:1)

Test Suites: 3 failed, 3 total
Tests:       0 total
Snapshots:   0 total
Time:        2.984 s
Ran all test suites.

 

// fucntion module
import * as admin from 'firebase-admin';
const firestore = admin.firestore();
import { onDocumentCreated } from 'firebase-functions/v2/firestore';

export const lowercaseData = onDocumentCreated('testDoc/{docId}', async (event) => {
  if (!event.data) {
    return;
  }
  const data = event.data.data();
  const bio = data.bio.toLowerCase();
  await firestore.doc(`testDoc/${event.params.docId}`).update({ bio });
});


// Test module

import 'jest';
import * as functions from 'firebase-functions-test';
import { lowercaseData } from '../functions/v2cloudFunctions';
import * as admin from 'firebase-admin';

admin.initializeApp();
const firestore = admin.firestore();

const testEnv = functions(
  {
    databaseURL: 'xxxx',
    projectId: 'xxx',
  },
  './service-account-key.json'
);

describe('lowercaseData', () => {
  let wrapped: any | null = null;
  // Applies only to tests in this describe block
  beforeAll(() => {
    wrapped = testEnv.wrap(lowercaseData as any);
  });

  it('converts the bio to lowercaseData', async () => {
    const path = 'testDoc/data1';
    const data = { bio: 'BIG' };

    // Create a Firestore snapshot
    const snap = testEnv.firestore.makeDocumentSnapshot(data, path);

    // Execute the function
    await wrapped(snap);

    const after = await firestore.doc(path).get();

    expect(after?.data()?.bio).toBe('big');
  });
});