Can't run unit tests with Jest

While running a most simple unit test I get TypeError: Cannot read property 'IsAndroid' of undefined as in issue #36 . However, building and running the app works perfectly fine.

Mocking react-native-sound via jest.mock('react-native-sound'); doesn’t help.

The test fails in line import myComponentWithANestedSubComponentWhichUsesRNSound from './'; of the following code snippet:

import 'react-native';
import React from 'react';
import renderer from 'react-test-renderer';

jest.mock('react-native-sound');

import myComponentWithANestedSubComponentWhichUsesRNSound from './';

describe('<ListItemVideo />', () => {

  it('renders correctly', () => {
    const tree = renderer.create(<myComponentWithANestedSubComponentWhichUsesRNSound />);
  });
});

[jsvegborn]

If mocked it like:

jest.mock('react-native-sound', () => {
  class SoundMock {
    constructor(path, type, callback) {}
  }

  SoundMock.prototype.setVolume = jest.fn();
  SoundMock.prototype.setNumberOfLoops = jest.fn();
  SoundMock.prototype.play = jest.fn();
  SoundMock.prototype.stop = jest.fn();

  SoundMock.setCategory = jest.fn();

  return SoundMock;
});

and the check for function calls in my tests like

import Sound from 'react-native-sound'; … expect(Sound.prototype.play).toHaveBeenCalled();

which seems to work for me. Maybe someone else finds it useful!

[dominictracey]

Try:

jest.mock('react-native-sound', () => 'Sound')