Unexpected token export with Lodash

Minimal repo: https://github.com/epicfaace/jest-bug-1

Issue My tests fail:

   C:\Users\arama\Documents\My Web Sites\WordPress\wp-content\plugins\CFF\node_modules\lodash-es\lodash.js:10
    export { default as add } from './add.js';
    ^^^^^^

    SyntaxError: Unexpected token export

My code:

import {set, unset, get, isArray} from 'lodash-es';

My jest config:

  "jest": {
    "transform": {
      "^.+\\.tsx?$": "ts-jest"
    },
    "testRegex": "(/__tests__/.*|(\\.|/)(test|spec))\\.(jsx?|tsx?)$",
    "moduleFileExtensions": [
      "ts",
      "tsx",
      "js",
      "jsx",
      "json",
      "node"
    ]
  }

I tried changing my jest config to the following, but it still doesn’t work:

  "jest": {
    "transform": {
      "^.+\\.tsx?$": "ts-jest"
    },
    "testRegex": "(/__tests__/.*|(\\.|/)(test|spec))\\.(jsx?|tsx?)$",
    "moduleFileExtensions": [
      "ts",
      "tsx",
      "js",
      "jsx",
      "json",
      "node"
    ],
    "transformIgnorePatterns": [
      "<rootDir>/node_modules/(?!lodash-es)"
    ]
  }

Issue Analytics

State:
Created 5 years ago
Reactions:23
Comments:7 (4 by maintainers)

Top GitHub Comments

12reactions

DorianGreycommented, Apr 23, 2018

lodash-es requires transpilation to work properly on Node with commonjs.

I.e. extend your transforms like this:

"transform": {
    "^.+\\.js$": "babel-jest"
}

And use a .babelrc in the root of your project with at least the transform-es2015-modules-commonjs plugin defined:

{
  "plugins": [
    "transform-es2015-modules-commonjs"
  ]
}

babel-jest should already be installed due to jest, I’m not sure about the plugin - might be required to install this manually.

3reactions

epicfaacecommented, Apr 22, 2018

@kulshekhar here it is! https://github.com/epicfaace/jest-bug-1

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