"SyntaxError: Cannot use import statement outside a module" error while testing React Native project with Jest and @testing-library/react-native?

Question

Error I'm getting Anytime I run npm test:

 FAIL  ./App.test.js

● Test suite failed to run

Jest encountered an unexpected token

This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.

By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".

Here's what you can do:
 • If you are trying to use ECMAScript Modules, see https://jestjs.io/docs/en/ecmascript-modules for how to enable it.
 • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
 • If you need a custom transformation specify a "transform" option in your config.
 • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

You'll find more details and examples of these config options in the docs:
https://jestjs.io/docs/en/configuration.html

Details:

/Users/bestes/Desktop/react-native-training/node_modules/react-native-status-bar-height/index.js:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import { Dimensions, Platform, StatusBar } from 'react-native';
                                                                                         ^^^^^^

SyntaxError: Cannot use import statement outside a module

  at Runtime.createScriptFromCode (node_modules/jest-runtime/build/index.js:1350:14)
  at Object.<anonymous> (node_modules/react-native-elements/src/config/index.js:1:1)

My Test:

import 'react-native';
import React from 'react';
import { render } from '@/../testing/test-utils'
import App from './App'


test('should render app component', () => {
  const result = render(<App />)

  expect(result).toMatchSnapshot()
})

My test-utils.js file:

import React from 'react'

import { render } from '@testing-library/react-native'
import { store } from '@/bootstrap/redux'
import { Provider } from 'react-redux'

const AllTheProviders = ({ children }) => {
  return (
    <Provider store={store}>
      {children}
    </Provider>
  )
}

const customRender = (ui, options) =>
  render(ui, { wrapper: AllTheProviders, ...options })

// re-export everything
export * from '@testing-library/react-native'

// override render method
export { customRender as render }

My package.json file:

{
  "name": "ReactNativeTraining",
  "version": "0.0.1",
  "private": true,
  "scripts": {
    "android": "react-native run-android",
    "ios": "react-native run-ios",
    "start": "react-native start",
    "test": "jest",
    "lint": "eslint ."
  },
  "dependencies": {
    "@react-native-community/geolocation": "2.0.2",
    "@react-native-community/masked-view": "0.1.10",
    "@react-native-picker/picker": "1.9.10",
    "@reduxjs/toolkit": "1.5.0",
    "axios": "0.21.1",
    "dayjs": "1.10.4",
    "lodash": "4.17.20",
    "react": "16.13.1",
    "react-native": "0.63.2",
    "react-native-config": "1.4.2",
    "react-native-elements": "3.0.0-alpha.1",
    "react-native-geocoding": "0.5.0",
    "react-native-gesture-handler": "1.9.0",
    "react-native-permissions": "3.0.0",
    "react-native-picker-select": "8.0.4",
    "react-native-reanimated": "1.13.2",
    "react-native-safe-area-context": "3.1.9",
    "react-native-screens": "2.17.0",
    "react-native-size-matters": "0.4.0",
    "react-native-vector-icons": "8.0.0",
    "react-navigation": "4.0.2",
    "react-navigation-stack": "1.5.4",
    "react-navigation-tabs": "2.4.1",
    "react-redux": "7.2.2"
  },
  "devDependencies": {
    "@babel/core": "7.12.10",
    "@babel/runtime": "7.12.5",
    "@react-native-community/eslint-config": "2.0.0",
    "@testing-library/jest-native": "4.0.1",
    "@testing-library/react-native": "7.2.0",
    "babel-jest": "^26.6.3",
    "babel-plugin-module-resolver": "4.0.0",
    "eslint": "7.18.0",
    "jest": "26.6.3",
    "metro-react-native-babel-preset": "0.64.0",
    "react-test-renderer": "16.13.1"
  },
  "type": "module",
  "jest": {
    "verbose": true,
    "preset": "react-native",
    "setupFilesAfterEnv": ["@testing-library/jest-native/extend-expect"],
    "transformIgnorePatterns": [
      "node_modules/(?!(react-native",
      "@react-native-community/geolocation",
      "@react-native-community/masked-view",
      "|@react-native-picker/picker",
      "|@reduxjs/toolkit",
      "|axios",
      "|dayjs",
      "|lodash",
      "|react",
      "|react-native",
      "|react-native-config",
      "|react-native-elements",
      "|react-native-geocoding",
      "|react-native-gesture-handler",
      "|react-native-permissions",
      "|react-native-picker-select",
      "|react-native-reanimated",
      "|react-native-safe-area-context",
      "|react-native-screens",
      "|react-native-size-matters",
      "|react-native-vector-icons",
      "|react-navigation",
      "|react-navigation-stack",
      "|react-navigation-tabs",
      "|react-redux",
      ")/)"
    ]
  }
}

My babel.config.js file:

module.exports = function (api) {
  api.cache(true)
  const presets = [
    'module:metro-react-native-babel-preset'
  ]
  const plugins = [
    [
      'module-resolver', {
        'root': ['./src/'],
        'extensions': ['.js', '.ios.js', '.android.js'],
        'alias': {
          '@': './src/'
        }
      }
    ]
  ]
  return {
    presets,
    plugins
  }
}

What I've tried: Adding "type": "module" to my root level package.json file, which fixed a similar error with exporting, Adding Transform Ignore Patterns to the Jest key in the package.json file. I'd added ALL of my dependencies to the transformIgnorePatterns as it kept throwing errors on each one, until I added all and now it throws on react-native modules imports.

Saiz

I'll add that this seems to only be an issue when attempting to import the App component. I'm not seeing the errors when I'm importing individual components. – Saiz

The error seems to be coming from the react-native-status-bar-height module. Where is that coming from? Have you tried including it in your transformIgnorePatterns? – Fluter

Answer 1

[Solved] Work for me Install below

npm install --save-dev @babel/core @babel/preset-env

after that create the "babel.config.js" file in the root and that content should be as below

module.exports = {
  presets: ['@babel/preset-env', '@babel/preset-react'],
  env: {
    test: {
      plugins: ["@babel/plugin-transform-runtime"]
    }
  }
};

Anthodium

its npm install --save-dev @babel/preset-env instead of npm install --save-dev @babel/present-env please update – Slagle

Thanks for the update..@MuhammadOwaisChaudhary – Anthodium

it does not resolve the problem for react native projects. Upgrading from 0.63.3 to 0.66.3 suddenly made some tests break with this weird error. – Intervenient

@Intervenient I have found a discussion on GitHub for the problem. The fix mentioned there works for React Native 0.64.0+. I have tested it on 0.66.4 after upgrading from 0.63.4 and it helped me. github.com/facebook/react-native/issues/… – Phosphide

Answer 2

It's working for me (react-native + expo + jest + @testing-library/react-native):

package.json

{
  ...

  "scripts": {
    "start": "expo start",
    "android": "expo start --android",
    "ios": "expo start --ios",
    "web": "expo start --web",
    "test": "jest"
  },
  "jest": {
    "preset": "jest-expo",
    "transformIgnorePatterns": [
      "/node_modules/(?!react-native)/.+"
    ],
    "transform": {
      "^.+\\.ts?$": "ts-jest",
      "^.+\\.tsx?$": "ts-jest"
    }
  }

...
}

babel.config.js

module.exports = function(api) {
  api.cache(true);
  return {
    presets: ['babel-preset-expo'],
  };
};

tsconfig.js

{
  "compilerOptions": {
    "jsx": "react",
    "allowJs": true
  },
  "extends": "expo/tsconfig.base"
}

Danziger