Trying to test using jest but running into issues - reactjs

Question

Im trying to test a component using jest. The component imports spacetime npm module, which uses es-modules on main
https://www.npmjs.com/package/spacetime
I'm running into the following issues:
● Test suite failed to run
Jest encountered an unexpected token
Jest failed to parse a file. This happens e.g. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is not configured to support such syntax.
Out of the box Jest supports Babel, which will be used to transform your files into valid JS based on your Babel configuration.
By default "node_modules" folder is ignored by transformers.
Here's what you can do:
• If you are trying to use ECMAScript Modules, see https://jestjs.io/docs/ecmascript-modules for how to enable it.
• If you are trying to use TypeScript, see https://jestjs.io/docs/getting-started#using-typescript
• 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/configuration
For information about custom transformations, see:
https://jestjs.io/docs/code-transformation
Details:
/Users/wscott/dev/pm/client/node_modules/spacetime/src/index.js:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,jest){import Spacetime from './spacetime.js'
^^^^^^
SyntaxError: Cannot use import statement outside a module
6 | import search from '../../assets/images/search.svg';
7 | import Dropdown from 'react-bootstrap/Dropdown';
> 8 | import spacetime from "spacetime";
| ^
9 | import languages from "../../libraries/languages/language-list";
10 | import { Rating } from 'react-simple-star-rating';
11 |
at Runtime.createScriptFromCode (node_modules/jest-runtime/build/index.js:1728:14)
at Object.<anonymous> (src/components/Mentor/MentorList.js:8:1)
Here's my jest.config.js file
module.exports = {
preset: 'ts-jest',
transform: {
'^.+\\.(ts|tsx)?$': 'ts-jest',
"^.+\\.(js|jsx)$": "babel-jest",
".+\\.(css|styl|less|sass|scss)$": "jest-transform-css"
},
"moduleNameMapper": {
"\\.(jpg|ico|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$": "<rootDir>/src/__mocks__/fileMock.js",
"\\.(css|less)$": "<rootDir>/src//__mocks__/fileMock.js"
},
"setupFiles":["./src/browserMocks.js"],
"globals": {
"window": {
location: {
href: ""
},
localStorage: {
getItem: () => {
}
}
},
"localStorage": {
getItem: () => {
}
}
}
};
Here's my babel.config.js file:
module.exports = {
presets:[
"#babel/preset-env",
"#babel/preset-react"
],
"env": {
"test": {
"plugins": ["#babel/plugin-transform-modules-commonjs"]
}
}
}
Can someone help?

Answer 1

Downgrading to 6.12.3 fixes the issue with jest. The issue is space time use es-module imports which jest doesn't support but downgrading should work

Answer 2

Try to set the transformIgnorePatterns property to let jest transform the file before tests:
transformIgnorePatterns: [
'node_modules/(?!(spacetime)/)',
],
This way you are telling to skip transformation for all your node_modules except spacetime, which will be transformed by babel-jest as is set in you configuration.