I'm trying to setup Jest on my react-native project but it hasn't been playing nice with bugsnag-react-native.

With my current test configuration I'm seeing errors related to bugsnag's leaveBreadcrumb function seen below:

 FAIL  app/__tests__/NetworkReducer.test.js

  ● Test suite failed to run



    TypeError: Cannot read property 'default' of undefined



      at Object.<anonymous> (app/__tests__/NetworkReducer.test.js:10:20)

          at Generator.next (<anonymous>)

          at Promise (<anonymous>)

I have a helper file that instantiates bugsnag:

helpers/bugSnag.js





//-------------------------------------------------------------------------------------------------

// Create a single instance of the bugsnag client so we don't have to duplicate our configuration

// anywhere.

//-------------------------------------------------------------------------------------------------

// https://docs.bugsnag.com/platforms/react-native/#basic-configuration



import { Client, Configuration } from 'bugsnag-react-native';

const config = new Configuration();

config.consoleBreadcrumbsEnabled = true;

config.notifyReleaseStages = ['testflight', 'production'];



const bugSnag = new Client(config);





export default bugSnag;

So in all my files I'm importing bugSnag from this helper file rather than declaring a new Client in each file, notably in my NetworkReducer.js where bugSnag.leaveBreadcrumb('someData') is causing me issues.

In my NetworkReducer.test.js I'm calling a mock:

 jest.mock(bugSnag, () => {

    return {

        leaveBreadcrumb: jest.fn()

    };

 });

where I'm also importing bugSnag from path/to/helpers/bugSnag

If I comment out the mock, I get a different error message on each of my reducer types that have a bugSnag.leaveBreadcrumb('someData') as seen below:

TypeError: _bugSnag2.default.leaveBreadcrumb is not a function



  at Object.network_prop_update (app/reducers/NetworkReducer.js:29:19)

  at app/reducers/createReducer.js:4:29

  at Object.<anonymous> (app/__tests__/NetworkReducer.test.js:80:29)

  at tryCallTwo (node_modules/promise/lib/core.js:45:5)

  at doResolve (node_modules/promise/lib/core.js:200:13)

  at new Promise (node_modules/promise/lib/core.js:66:3)

I thought I had a handle on this jest thing, and mocking, but I guess I've been proven wrong. I've attached my Jest's setup.js for extra reference:

    jest.mock('Linking', () => {

    return {

        addEventListener: jest.fn(),

        removeEventListener: jest.fn(),

        openURL: jest.fn(),

        canOpenURL: jest.fn(),

        getInitialURL: jest.fn(),

    };

});





jest.mock('PushNotificationIOS', () => {

    return {

        addEventListener: jest.fn(),

        requestPermissions: jest.fn(() => Promise.resolve()),

        getInitialNotification: jest.fn(() => Promise.resolve()),

    };

});





jest.mock('react-native-intercom', () => {

    return {

        registerIdentifiedUser: jest.genMockFn().mockReturnValue(Promise.resolve()),

        registerUnidentifiedUser: jest.genMockFn().mockReturnValue(Promise.resolve()),

        updateUser: jest.genMockFn().mockReturnValue(Promise.resolve()),

        reset: jest.genMockFn().mockReturnValue(Promise.resolve()),

        logEvent: jest.genMockFn().mockReturnValue(Promise.resolve()),

        handlePushMessage: jest.genMockFn().mockReturnValue(Promise.resolve()),

        displayMessenger: jest.genMockFn().mockReturnValue(Promise.resolve()),

        hideMessenger: jest.genMockFn().mockReturnValue(Promise.resolve()),

        displayMessageComposer: jest.genMockFn().mockReturnValue(Promise.resolve()),

        displayMessageComposerWithInitialMessage: jest.genMockFn().mockReturnValue(Promise.resolve()),

        displayConversationsList: jest.genMockFn().mockReturnValue(Promise.resolve()),

        getUnreadConversationCount: jest.genMockFn().mockReturnValue(Promise.resolve()),

        setLauncherVisibility: jest.genMockFn().mockReturnValue(Promise.resolve()),

        setInAppMessageVisibility: jest.genMockFn().mockReturnValue(Promise.resolve()),

        setupAPN: jest.genMockFn().mockReturnValue(Promise.resolve()),

        registerForPush: jest.genMockFn().mockReturnValue(Promise.resolve()),

        setUserHash: jest.genMockFn().mockReturnValue(Promise.resolve()),

        setBottomPadding: jest.genMockFn().mockReturnValue(Promise.resolve()),

        addEventListener: jest.fn(),

        removeEventListener: jest.fn()

    };

});





jest.mock('bugsnag-react-native', () => {

    return {

        leaveBreadcrumb: jest.fn(),

        Configuration: jest.fn(),

        Client: jest.fn()

    };

});