reactjs - 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"