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Jest, How to mock an imported callback in Object Destructuring?

I did the tests in the following way, but it bothers me how I need to import an object with the functions, instead of just importing the functions.
this works
//service.test.js
const get = require('../../modules/bankUser/model/getRegisteredUser');
get.getRegisteredUser = jest.fn()
.mockImplementationOnce(async () => mock)
.mockImplementationOnce(async () => mockUpdated);
//service.js
const get = require('../model/getRegisteredUser');
const testedFunction () => {
const depositReciver = await get.getRegisteredUser(depositName, depositCpf);
}
this dosent
//service.test.js
const get = require('../../modules/bankUser/model/getRegisteredUser');
get.getRegisteredUser = jest.fn()
.mockImplementationOnce(async () => mock)
.mockImplementationOnce(async () => mockUpdated);
//service.js
const { getRegisteredUser } = require('../model/getRegisteredUser');
const testedFunction () => {
const depositReciver = await getRegisteredUser(depositName, depositCpf);
}
I'm triyng this (way):
//service.test.js
const get = require('../../modules/bankUser/model/getRegisteredUser');
jest.mock('../../modules/bankUser/model/getRegisteredUser');
get.mockImplementationOnce(() => ({ getRegisteredUser: () => mockObject }));
jest returns this:
TypeError: get.mockImplementationOnce is not a function
also I've tried to import like this
//service.test.js
const { getRegisteredUser } = require('../../modules/bankUser/model/getRegisteredUser');
jest.mock('../../modules/bankUser/model/getRegisteredUser');
getRegisteredUser.mockImplementationOnce(() => ({ getRegisteredUser: () => mockObject }));
EDIT
//getRegisteredUser.js
const { getConnection } = require('../../../global/connection');
const getRegisteredUser = async (userName, cpf) => {
const db = await getConnection('Data-Base');
const res = await db.collection('Collection')
.findOne({ userName, cpf });
return res;
};
module.exports = { getRegisteredUser };

The example you are pointing [https://jestjs.io/docs/es6-class-mocks#replacing-the-mock-using-mockimplementation-or-mockimplementationonce][1]
is related to the default export but I think you are using named export in your code.
There are multiple ways to do so
One Way
const get = require('../../modules/bankUser/model/getRegisteredUser');
jest.mock('../../modules/bankUser/model/getRegisteredUser');
get.getRegisteredUser.mockImplementationOnce(() => mockObject);
Second Way
jest.mock('../../modules/bankUser/model/getRegisteredUser', () => ({
...jest.requireActual('../../modules/bankUser/model/getRegisteredUser'),
getRegisteredUser: jest.fn().mockImplementation(() => mockObject),
}))
An Another Way
We can also mock a module using the __mocks__ directory which is inbuilt feature of jest
And at the end never forgot to call clearAllMocks() after each test else it may impact the output of other tests.
afterEach(() => {
jest.clearAllMocks();
});

Is it possible to mock API calls with Jest in NodeJS without jest.mock('module')?

My NodeJS application has to do some API requests, so I'm mocking their return as my tests are just for my application's business logic. However, there's two things that I quite didn't understand.
I'm using jest's mockImplementation method to change the return of my service, but I can't make it work without calling jest.mock with the service beforehand.
Also, if I try to set automock: true in my jest.config.js, it returns me an error:|
TypeError: Cannot set property 'gracefulify' of undefined
Here's my test.js code in where I'm testing a function that calls automation.js, which has my application logic and make the calls for my services:
const automation = require('../automations/fake.automation');
// MOCKS
const mockedBlingProduct = require('../mocks/bling-product.mocks.json');
const mockedShopifyCreatedProduct = require('../mocks/shopify-created-product.mocks.json');
// SERVICES
const BlingProductService = require('../services/bling-product.service');
const ShopifyProductService = require('../services/shopify-product.service');
jest.mock('../services/bling-product.service');
jest.mock('../services/shopify-product.service');
describe('Automation test', () => {
beforeEach(() => {
const blingMockedReturn = jest.fn(() => {
return mockedBlingProduct;
});
const shopifyMockedReturn = jest.fn(() => {
return mockedShopifyCreatedProduct;
});
BlingProductService.mockImplementation(() => {
return {
list: blingMockedReturn
};
});
ShopifyProductService.mockImplementation(() => {
return {
create: shopifyMockedReturn
};
});
});
it('should return status SUCCESS', async () => {
const result = await
.run();
expect(result).toEqual({ status: 'SUCCESS' });
});
});
And here's the code of one of my services, keep in mind that the logic behind the API calls is abstracted from the service. In the mockImplementation I'm trying to overwrite the list and create functions inside them:
class BlingPriceService {
async list(query = {}) {
const httpMethod = 'GET';
const resource = 'produtos/page={pageNumber}/json';
const options = {
queryString: query,
urlParams: {
pageNumber: 1,
}
};
return blingComponent.request(httpMethod, resource, options);
}
}
module.exports = BlingPriceService;

const automation = require('../automations/fake.automation');
// MOCKS
const mockedBlingProduct = require('../mocks/bling-product.mocks.json');
const mockedShopifyCreatedProduct = require('../mocks/shopify-created-product.mocks.json');
// SERVICES
const BlingProductService = require('../services/bling-product.service');
const ShopifyProductService = require('../services/shopify-product.service');
describe('Automation test', () => {
beforeAll(() => {
jest.spyOn(BlingProductService.prototype, 'list').mockImplementation(() => Promise.resolve(mockedBlingProduct));
jest.spyOn(ShopifyProductService.prototype, 'list').mockImplementation(() => Promise.resolve(mockedShopifyCreatedProduct));
});
afterAll(() => {
jest.restoreAllMocks();
});
it('should return status SUCCESS', async () => {
const result = await automation.run();
expect(result).toEqual({ status: 'SUCCESS' });
});
});

How to mock optimizelySDK.createInstance().onReady() using Jest?

Here is my mock file __mocks__/#optimizely/optimizely-sdk.js
const optimizelySDK = jest.requireActual('#optimizely/optimizely-sdk')
optimizelySDK.createInstance().onReady = () => ({ success: false }))
module.exports = optimizelySDK
Here is my test file Optimizely.test.js
import optimizelySDK from '#optimizely/optimizely-sdk'
test('onReady', () => {
const response = optimizelySDK.createInstance().onReady()
expect(response).toBe({ success: false })
})
I think I might be going about this all wrong. This worked perfectly when I try this with lodash. I believe this is because optimizelySDK is a class. I think I should be mocking that instead. How do I successfully mock and test optimizelySDK?

For anyone who came across this on Google, I had the same problem and got it working with jest:
jest.mock('#optimizely/optimizely-sdk', () => ({
...jest.requireActual('#optimizely/optimizely-sdk'),
createInstance: () => ({
getEnabledFeatures: jest.fn().mockReturnValueOnce(['featureA', 'featureB']),
onReady: jest.fn().mockResolvedValueOnce({ status: 200 })
})
}))
describe('my-test', () => {
it('should pass', async () => {
const result = await getFeatures()
console.log(result) // ['featureA', 'featureB']
// assert on result here
});
});
where my code looked something like:
const getFeatures = async (event) => {
try {
const optimizelyInstance = optimizelySDK.createInstance({
sdkKey: process.env.OPTIMIZLEY_SDK_KEY,
});
const optimizelyParameters = {}
return optimizelyInstance.onReady().then(() => {
const result = optimizelyInstance.getEnabledFeatures('id', optimizelyParameters);
return result;
});
} catch (err) {
console.error('Could not get features', err);
}
};

Unable to unit test firebase function in Sinon

I am trying to unit test a JavaScript promise, that contains a firebase query, using mocha, chai, sinon. I am trying to mock the database using sinon rather than actually making a request to the database. However, I am unable to implement it correctly.
Here is my promise in the file '/services/pr_services:
exports.getUserInfo = (userId) => {
return new Promise((resolve, reject) => {
const userProfile = {};
const userProfileRef = database.ref('profiles').child(userId);
userProfileRef.once('value', (snap) => {
if (snap.exists()) {
const userProfileData = snap.val();
resolve(userProfile);
} else {
reject();
}
});
});
};
The variable database contains the database configuration like credentials, database url, etc
Here is my code for the test case:
const chai = require('chai');
const sinon = require('sinon');
const admin = require('firebase-admin');
const database = require('../database');
const services = require('../services/pr_services');
const should = chai.should();
describe('Database functions', () => {
let adminInitStub;
before(() => {
adminInitStub = sinon.stub(admin, 'initializeApp');
});
describe('get profile info', () => {
it('should return a non empty object', (done) => {
beforeEach(() => {
services.getUserInfo = sinon.stub();
});
afterEach(() => {
services.getUserInfo.reset();
});
const userId = 'jim123';
const snap = {
name: 'Jim Dani',
address: 'Porto'
};
const userProfileRef = database.ref('profiles').child(userId);
userProfileRef.once('value').returns(Promise.resolve(snap));
services.getUserInfo
.then(info => {
info.should.be.a('object');
info.should.equal(snap);
done();
})
.catch(err => {
should.not.exist(err);
done();
});
});
});
after(() => {
adminInitStub.restore();
test.cleanup();
});
});
Can anyone point out where I am going wrong and kindly point me in right direction.
Thanks.

How to mock dependencies for testing in node.js?

I want to write some unit-tests for my applicatin, can I somehow "mock" some dependencies used with require('dependencyname')?

You are looking for Proxyquire :)
//file1
var get = require('simple-get');
var assert = require('assert');
module.exports = function fetch (callback) {
get('https://api/users', callback);
};
//test file
var proxyquire = require('proxyquire');
var fakeResponse = {status:200};
var fetch = proxyquire('./get', {
'simple-get': function (url, callback) {
process.nextTick(function () {
callback(null, fakeResponse)
})
}
});
fetch(function (err, res) {
assert(res.statusCode, 200)
});
Straight out of their docs.

yes, for example with jest => https://facebook.github.io/jest/
// require model to be mocked
const Mail = require('models/mail');
describe('test ', () => {
// mock send function
Mail.send = jest.fn(() => Promise.resolve());
// clear mock after each test
afterEach(() => Mail.send.mockClear());
// unmock function
afterAll(() => jest.unmock(Mail.send));
it('', () =>
somefunction().then(() => {
// catch params passed to Mail.send triggered by somefunction()
const param = Mail.send.mock.calls[0][0];
})
);
});