Unable to mock via jest

[Mookiies]

testing my code using this package is turning out to be seemingly impossible. I tried mocking the react-native-quick-actions module in jest via:

jest.mock('react-native-quick-actions', () => {
  return {
    clearShortcutItems: jest.fn(),
    isSupported: jest.fn(),
    setShortcutItems: jest.fn(),
  }
});

That didn't work because it kept returning this error: TypeError: _reactNativeQuickActions2.default.popInitialAction is not a function which confuses me, because I can't find _reactNativeQuickActions2 anywhere in your code here.

I tried this again, trying this instead:

jest.mock('react-native-quick-actions', () => {
  return {
    QuickActions: {
      clearShortcutItems: jest.fn(),
      isSupported: jest.fn(),
      setShortcutItems: jest.fn(),
    },
  };
});

And same result.

So my next approach was to try and mock the QuickActions object itself as a native module, like so:

jest.mock('NativeModules', () => {
  return {
    DeviceEventEmitter: () => ({
      addListener: jest.fn(),
    }),
    RNQuickActionManager: () => ({
      initialAction: jest.fn(),
      isSupported: jest.fn(),
    }),
    QuickActions: {
      clearShortcutItems: jest.fn(),
      isSupported: jest.fn(),
      setShortcutItems: jest.fn(),
      popInitialAction: jest.fn(),
    },
  };
});

which also gave the same error: TypeError: _reactNativeQuickActions2.default.popInitialAction is not a function

Then I tried mocking higher up in its own mocked module file:

import { NativeModules } from 'react-native';

NativeModules.QuickActions = {
  /**
   * An initial action will be available if the app was cold-launched
   * from an action.
   *
   * The first caller of `popInitialAction` will get the initial
   * action object, or `null`. Subsequent invocations will return null.
   */
  popInitialAction: jest.fn(),

  /**
   * Adds shortcut items to application
   */
  setShortcutItems: jest.fn(),

  /**
   * Clears all previously set dynamic icons
   */
  clearShortcutItems: jest.fn(),

  /**
   * Check if quick actions are supported
   */
  isSupported: jest.fn(),
};

which again threw the same error.

I'm very stuck on where to go from here. If you have any recommendations, I would greatly appreciate it. Thanks.

[jordanbyron]

Hey @MalcolmScruggs,

Sorry to hear you are having problems stubbing out this library in your tests. It sounds like you are asking the more generic question: "How do I mock (or stub) out ES6 imports in jest". I took a look over at stack overflow for you and found this:

https://stackoverflow.com/questions/40465047/how-can-i-mock-an-es6-module-import-using-jest#40486695

This is a bug tracker, so if you find something about this library that is broken or could be improved to help with testing, feel free to open up another ticket.

[Mookiies]

Based on the way this package is setup, using jest to mock it is extremely difficult and unwieldy. To solve this issue I wrapped the API of this package in my own interface to easily mock it.

[jordanbyron]

Thanks for the update Malcom. Again if you have any suggestions or ideas for how this library could be easier to test with Jest, or in general, I’m all ears.

[Mookiies]

Jest gives very confusing error messages, so my error was mainly understanding what jest was giving back. Nothing wrong with the library, using this in a __mocks__ directory worked as expected:

module.exports = {
  /**
   * An initial action will be available if the app was cold-launched
   * from an action.
   *
   * The first caller of `popInitialAction` will get the initial
   * action object, or `null`. Subsequent invocations will return null.
   */
  popInitialAction: jest.fn(() => Promise.resolve()),

  /**
   * Adds shortcut items to application
   */
  setShortcutItems: jest.fn(),

  /**
   * Clears all previously set dynamic icons
   */
  clearShortcutItems: jest.fn(),

  /**
   * Check if quick actions are supported
   */
  isSupported: jest.fn(),
};