Jest mock inner function

Question

I have one file called helper.js that consist of two functions

export const funcA = (key) => {
   return funcB(key)
};

export const func         


        

Answer 1

Late answer but this should work. Also you should test funcB in its own file and not inside the 'helper' tests.

import { funcB } from './funcB';
import { funcA } from './helper';

jest.mock('./funcB');

describe('helper', () => {
    test('test funcA', () => {
        const funcBSpy = jest.fn();
        funcB.mockImplementation(() => funcBSpy());

        expect(funcBSpy).toHaveBeenCalledTimes(1);
    });
});