How to resolve “Cannot use import statement outside a module” in jest

Question

I have a React application (not using Create React App) built using TypeScript, Jest, Webpack, and Babel. When trying to run "yarn jest", I get the following error:

I have tried removing all packages and re-adding them. It does not resolve this. I have looked at similar questions and documentation and am still misunderstanding something. I went so far as to follow another guide for setting up this environment from scratch and still received this issue with my code.

Dependencies include...

"dependencies": {
        "@babel/plugin-transform-runtime": "^7.6.2",
        "@babel/polyfill": "^7.6.0",
        "babel-jest": "^24.9.0",
        "react": "^16.8.6",
        "react-dom": "^16.8.6",
        "react-test-renderer": "^16.11.0",
        "source-map-loader": "^0.2.4"
    },
    "devDependencies": {
        "@babel/core": "^7.6.0",
        "@babel/preset-env": "^7.6.0",
        "@babel/preset-react": "^7.0.0",
        "@types/enzyme": "^3.9.2",
        "@types/enzyme-adapter-react-16": "^1.0.5",
        "@types/jest": "^24.0.13",

The component's import lines...

import * as React from "react";
import { BrowserRouter as Router, Route, Switch } from "react-router-dom";
import HomePage from "./components/pages";
import {
    Footer,
    Header,
    Navigation,
} from "./components/shared";

The test file....

import * as React from "react";
import * as renderer from "react-test-renderer";
import App from "../App";

it("Renders the Footer correctly", () => {
    const tree = renderer
        .create(<App />)
        .toJSON();
    expect(tree).toMatchSnapshot();
});

I expected to be able to use named imports in my components without my tests blowing up. It appears to fix the issue if I only use default imports through my solution, but I would prefer to not go that route.

Answer 1

Also using Babel, Typescript and Jest. Had the same failure, driving me crazy for hours. Ended up creating a new babel.config.js file specifically for the tests. Had a large .babelrc that wasn't getting picked up by jest no matter what i did to it. Main app still uses the .babelrc as this overrides babel.config.js files.

Install jest, ts-jest and babel-jest:

npm i jest ts-jest babel-jest

babel.config.js (only used by jest)

module.exports = {presets: ['@babel/preset-env']}

jest.config.js

module.exports = {
  preset: 'ts-jest',
  transform: {
    '^.+\\.(ts|tsx)?$': 'ts-jest',
    "^.+\\.(js|jsx)$": "babel-jest",
  }
};

package.json

  "scripts": {
    "test": "jest"

Answer 2

Use Babel to transpile those JS Modules and you'll be able to write your tests with es6.

Install Babel/preset-env

npm i -D @babel/preset-env

Create a babel configuration file with the preset

//babel.config.js
module.exports = {presets: ['@babel/preset-env']}

Answer 3

I solved this by migrating the .babelrc file to babel.config.js! Shocker.

Answer 4

Solution: my named imports were coming from index.js files and I believe ts-jest needed them as index.ts files (I'm using Typescript). If anyone else runs into this error, couldn't hurt to check if you derped your file extensions.

I wasted a lot of time on this, unfortunately, but I learned a lot about webpack configurations and Babel.

Answer 5

try this thing if you are using babel 6

1. Adding @babel/plugin-transform-modules-commonjs in the plugin section of babel.config.js

or

2. For my case import issue was due to the react file drop by adding that to transfromIgnorePatterns

"transformIgnorePatterns": ["/node_modules/(?!react-file-drop)"]

Answer 6

For future references,

I solved the problem by using below jest config, after reading Logan Shoemaker's answer.

module.exports = {
  verbose: true,
  setupFilesAfterEnv: ["<rootDir>src/setupTests.ts"],
  moduleFileExtensions: ["js", "jsx", "ts", "tsx"],
  moduleDirectories: ["node_modules", "src"],
  moduleNameMapper: {
    "\\.(css|less|scss)$": "identity-obj-proxy"
  },
  transform: {
    '^.+\\.(ts|tsx)?$': 'ts-jest',
    "^.+\\.(js|jsx)$": "babel-jest",
    "\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$": "<rootDir>/__mocks__/file.js",
  }
};

Answer 7

Matching file extensions:

I importing a file named Todo.jsx in the root as ./src/Todo/. Whenever I changed it to Todo.js the problem went away.

Disclaimer: I'm not sure what the requirement is for having your file extension as jsx vs js for your components. It did not effect me at all, but I could imagine it could mess with intellisense or snippets.

Answer 8

I encountered the same problem with Typescript, Jest, and VueJS/VueCli 3. The normal build has no problem. only happens for Jest. I struggled for hours by searching. But no answer actually works. In my case, I have a dependency on my own typescript package which I specific "target": "es6" in the tsconfig.json. That's the root cause. So the solution is simply to change the dependent's (Not the same project) back to es5 tsconfig.json:

{
  "compilerOptions": {
    "target": "es5",
    ...
  },
  ...
}

Answer 9

If you're using TypeScript, and you have a tsconfig.json file, try removing "module": "esnext" if you're using it