Invariant Violation: Native module cannot be null. with "preset": "react-native",

[jcollum]

Repo: https://github.com/jcollum/kishar-nine/tree/05-testing

Related (closed) #2208

$ versions
npm 3.10.8
node v6.9.1
OS:
ProductName:	Mac OS X
ProductVersion:	10.11.6
BuildVersion:	15G31

$ cat package.json 

    "react-native": "~0.39.1",
...
 "jest": {
    "preset": "react-native",
    "testRegex": "./test/.*.js$"
  },
  "devDependencies": {
...
    "jest": "~18.0.0",

$ npm test

> [email protected] test /Users/collumj/research/kishar-nine
> jest

 FAIL  test/index.android.js
  ● Test suite failed to run

    Invariant Violation: Native module cannot be null.
      
      at invariant (node_modules/fbjs/lib/invariant.js:38:15)
      at Linking.NativeEventEmitter (node_modules/react-native/Libraries/EventEmitter/NativeEventEmitter.js:32:1)
      at new Linking (node_modules/react-native/Libraries/Linking/Linking.js:119:141)
      at Object.<anonymous> (node_modules/react-native/Libraries/Linking/Linking.js:191:16)
      at Object.get Linking [as Linking] (node_modules/react-native/Libraries/react-native/react-native.js:91:22)
      at Object.<anonymous> (node_modules/react-native-experimental-navigation/NavigationRootContainer.js:15:36)

The test is pretty simple:

$ cat test/index.android.js 
import 'react-native';
import React from 'react';
import Index from '../index.android.js';

// Note: test renderer must be required after react-native.
import renderer from 'react-test-renderer';

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

Steps to reproduce:

1. git clone https://github.com/jcollum/kishar-nine.git k9fresh
2. cd k9fresh/
3. git checkout 05-testing && npm install && npm test

The tests work on the 00 branch but since upgrading react and jest they fail and in a very cryptic way. They don't appear to be actually running.

[cpojer]

Did they fail because of the react or because of the Jest update?

[jcollum]

$ gd b1d14..041841 package.json
diff --git a/package.json b/package.json
index 030296e..1b7a9f7 100644
--- a/package.json
+++ b/package.json
@@ -20,16 +20,12 @@
   },
   "jest": {
     "preset": "react-native",
-    "globals": {
-      "__DEV__": true
-    },
-    "testRegex": "./test/.*.js$",
-    "rootDir": "."
+    "testRegex": "./test/.*.js$"
   },
   "devDependencies": {
     "babel-jest": "17.0.2",
     "babel-preset-react-native": "1.9.0",
-    "jest": "17.0.3",
+    "jest": "~18.0.0",
     "react-test-renderer": "15.4.1"
   }
 }

Looks like jest. That stuff in there with globals and rootDir made no difference, still failing.

[thymikee]

Have you tried using babel-jest v18?

[jcollum]

Yes, just did:

$ cat node_modules/babel-jest/package.json | grep version
        "type": "version"
    "type": "version"
  "version": "18.0.0"

collumj@por-collumj-m ~/research/kishar-nine (05-testing) 12:02:12  
$ npm test

> [email protected] test /Users/collumj/research/kishar-nine
> jest

 FAIL  test/index.ios.js
  ● Test suite failed to run

    Invariant Violation: Native module cannot be null.
      
      at invariant (node_modules/fbjs/lib/invariant.js:38:15)

[jcollum]

Did a full wipe of node_modules, install and test with this package.json:

"dependencies": {
    "lodash": "~4.17.2",
    "react": "15.4.1",
    "react-native": "~0.39.1",
    "react-native-router-flux": "~3.37.0",
    "react-redux": "~4.4.6",
    "redux": "~3.6.0",
    "redux-thunk": "~2.1.0"
  },
  "jest": {
    "preset": "react-native",
    "testRegex": "./test/.*.js$"
  },
  "devDependencies": {
    "babel-jest": "~18.0.0",
    "babel-preset-react-native": "1.9.1",
    "jest": "~18.0.0",
    "react-test-renderer": "15.4.1"
  }

Same result.

[thymikee]

Are you sure your tests works on Jest 17?
I've just checkout your branch, check Jest 18 and 17 and both throw the same error.

[jcollum]

Did you downgrade RN at the same time? I think that may be where the problem lies:

$ rm -rf node_modules/ && git checkout 02-routing && npm install --quiet && npm test

All tests pass.

Do the same with 03-redux-counter and both tests fail for the Invariant error. Diff the package.json between the two and you see:

$ git diff 02-routing...03-redux-counter package.json
...
-    "react-native": "0.38.0"
+    "react-native": "~0.39.1",

So, should I close this and open it on RN?

[thymikee]

Nope, no changes besides Jest. I think RN repo will be a better place to tackle this. Thanks!

[github-actions]

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