How to stub exported function in ES6?

Question

I have file foo.js:

export function bar (m) {   console.log(m); } 

And another file that uses foo.js, cap.js:

import { bar } from 'foo';  export default m => {   // Some logic that I need to test   bar(m); } 

I have test.js:

import cap from 'cap'  describe('cap', () => {   it('should bar', () => {       cap('some');   }); }); 

Somehow I need override implementation of bar(m) in test. Is there any way to do this?

P.S. I use babel, webpack and mocha.

Answer 1

Ouch.. I found solution, so I use sinon to stub and import * as foo from 'foo' to get object with all exported functions so I can stub them.

import sinon from 'sinon'; import cap from 'cap'; import * as foo from 'foo';  sinon.stub(foo, 'bar', m => {     console.log('confirm', m); });  describe('cap', () => {   it('should bar', () => {     cap('some');   }); });