Following is the error I receive on running a Sample testcase: My Testcase: My jest configuration in package.json: My dependencies in package.json: expo version: 37.0.0 react: `16.9.0 react-native: “https://github.com/expo/react-native/archive/sdk-37.0.1.tar.gz” Answer Found the solution on the Ex…

Jest testcase breaking in React Native Expo

Following is the error I receive on running a Sample testcase:

Expected react-native/jest-preset to define transform[^.+.(bmp|gif|jpg|jpeg|mp4|png|psd|svg|webp)$]
react-native/jest-preset contained different transformIgnorePatterns than expected
 FAIL  ./App.test.js
  ● Test suite failed to run

    Cannot find module 'react-native/Libraries/LogBox/LogBox' from 'setup.js'

      at Resolver.resolveModule (node_modules/jest-expo/node_modules/jest-resolve/build/index.js:299:11)
      at Object.<anonymous> (node_modules/jest-expo/src/preset/setup.js:155:6)

My Testcase:

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

import App from './App';

describe('<App />', () => {
  it('has 1 child', () => {
    const tree = renderer.create(<App />).toJSON();
    expect(tree.children.length).toBe(1);
  });
});

My jest configuration in package.json:

"jest": {
    "preset": "jest-expo",
    "transformIgnorePatterns": [
      "<rootDir>/node_modules/(?!(jest-)?react-native|react-clone-referenced-element|@react-native-community|expo(nent)?|@expo(nent)?/.*|react-navigation|@react-navigation/.*|@unimodules/.*|unimodules|sentry-expo|native-base|@sentry/.*)",
      "node_modules/(?!(react-native|my-project|react-native-button)/)"
    ]
  },

My dependencies in package.json:

    "jest": "^26.4.2",
    "jest-expo": "^39.0.0",
    "jest-react-native": "^18.0.0",
    "react-test-renderer": "^16.13.1",

expo version: 37.0.0

react: `16.9.0

react-native: "https://github.com/expo/react-native/archive/sdk-37.0.1.tar.gz"

Answer

Found the solution on the Expo thread mentioning the exact same issue here.

It looks like you’re using jest-expo v39 with a project running SDK37. LogBox was released with React Native 0.63 which is what SDK39 is using. Can you try running with v37.0.0 and see if that resolves the issue?

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Answer