javascripttypescriptjestjsnext.jsbabel-jest

Next.js and Jest: SyntaxError: Cannot use import statement outside a module


I am working on a Next.js project using TypeScript and for testing I use Jest and React Testing Lib. However, I encounter a SyntaxError: Cannot use import statement outside a module for components where I import rehype-raw.

As far as I understand this, Jest does not support ES6 so node_modules may need to be transformed. This can be configured using transformIgnorePatterns. For example if rehype-raw is causing this error using "transformIgnorePatterns": ["node_modules/(?!rehype-raw)/"] should allow transformation of the rehype-raw but no other module. And thus solve this error.

However, this does not work for me. But idk why and how I can solve this. No suggested solution I have found could solve this problem. I have attached my error output, jest.config.js and babel.rc file below.

Error output

 FAIL  test/pages/companies/[id].test.tsx                  
  ● Test suite failed to run

    Jest encountered an unexpected token

    [...]

    Details:

    /path/frontend-job/node_modules/rehype-raw/index.js:7
    import {raw} from 'hast-util-raw'
    ^^^^^^

    SyntaxError: Cannot use import statement outside a module

      3 | import Image from 'next/image';
      4 | import { Remark } from 'react-remark';
    > 5 | import rehypeRaw from 'rehype-raw';
        | ^
      6 | import rehypeSanitize from 'rehype-sanitize';
      7 | import { logError } from '@utils/logger';
      8 |

      at Runtime.createScriptFromCode (node_modules/jest-runtime/build/index.js:1728:14)
      at Object.<anonymous> (components/markdown/JobMarkdown.tsx:5:1)

jest.config.js

const { resolve } = require('path');

module.exports = {
  roots: ['<rootDir>'],
  moduleFileExtensions: ['js', 'jsx', 'ts', 'tsx', 'json', 'node'],
  setupFiles: ['<rootDir>/test/setup.js'],
  testPathIgnorePatterns: ['<rootDir>[/\\\\](node_modules|.next)[/\\\\]'],
  transform: {
    '^.+\\.(ts|tsx)$': 'babel-jest',
  },
  transformIgnorePatterns: [
    'node_modules/(?!rehype-raw)/',
  ],
  watchPlugins: [
    'jest-watch-typeahead/filename',
    'jest-watch-typeahead/testname',
  ],
  moduleNameMapper: {
    // Force mocks: https://github.com/facebook/jest/issues/4262
    '@api/axios': '<rootDir>/test/__mocks__/axios.js',
    // Normal module aliases
    '\\.(css|less|sass|scss)$': 'identity-obj-proxy',
    '\\.(gif|ttf|eot|svg|png)$': '<rootDir>/test/__mocks__/fileMock.js',
    '^@test/(.*)$': resolve(__dirname, './test/$1'),
    '^@test/faker/(.*)$': resolve(__dirname, './test/faker/$1'),
    '^@components/(.*)$': resolve(__dirname, './components/$1'),
    '^@pages/(.*)$': resolve(__dirname, './pages/$1'),
    '^@utils/(.*)$': resolve(__dirname, './utils/$1'),
    '^@api/(.*)$': resolve(__dirname, './api/$1'),
    '^@store/(.*)$': resolve(__dirname, './store/$1'),
  },
  testEnvironment: 'jsdom',
};

babel.rc

{
  "presets": ["next/babel"]
}

Solution

  • Next has already out-of-the-box support for Jest, I'd suggest you follow the steps provided in the docs.