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Jest not properly mocking library

See original GitHub issue

When trying to run tests on Jest for my app which uses react-native-fcm I get error:

Invariant Violation: Native module cannot be null.

      at invariant (node_modules/fbjs/lib/invariant.js:44:15)
      at new NativeEventEmitter (node_modules/react-native/Libraries/EventEmitter/NativeEventEmitter.js:32:1)
      at Object.<anonymous> (node_modules/react-native-fcm/index.js:3:18)
      at Object.<anonymous> (app/components/MyComponent.js:6:21)

(MyComponent.js:6 is import FCM from 'react-native-fcm';)

Version info:

react-native-fcm@9.6.2
react-native@0.44.3

This problem has been earlier reported, but closed as https://github.com/evollu/react-native-fcm/issues/435

Issue Analytics

State:
Created 6 years ago
Comments:5 (3 by maintainers)

Top GitHub Comments

3reactions

evollucommented, Oct 1, 2017

will update code fixed in 9.7.2

1reaction

evollucommented, Oct 1, 2017

try replace this like https://github.com/evollu/react-native-fcm/blob/master/index.js#L3 with const EventEmitter = new NativeEventEmitter(NativeModules.RNFIRMessaging || {});