CameraSettings-AddingSpy.js

import React from 'react';
import { shallow } from 'enzyme';
import mockStore from 'redux-mock-store';

import sinon from 'sinon';
import { NativeModules } from 'react-native';

const initialState = {
  preferences: {
    save_photos_locally: true,
    open_to_camera: true,
  },
};

import CameraSettings from 'components/menu/CameraSettings';

describe('Testing CameraSettings', () => {
  it('calls actions as expected when toggling switches', () => {
    const wrapper = shallow(
      <CameraSettings />,
      { context: { store: mockStore(initialState) } },
    );
    const render = wrapper.dive();

    const saveToPhoneSpy = sinon.spy(NativeModules.PhotoActions, 'saveToPhone');
  
    render.find('Switch').forEach(child => {
      child.simulate('valueChange');
    });

    expect(saveToPhoneSpy.calledOnce).toBe(true);
  });
});