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Why isn't jest handling ES Module dependencies?

My package imports an ESM package called c2pa. When I run jest I get an error like this:
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
I believe the docs for ECMAScript Modules are for if my package is ESM, but I am having an issue with a dependency.
I also updated my Jest config to try out transformIgnorePatterns override mentioned in the error and Jest gives an error: "SyntaxError: Unexpected token export".
const babelConfig = require('../../babel.config.json');
module.exports = {
preset: 'ts-jest/presets/js-with-babel',
testEnvironment: 'jsdom',
roots: ['tests', 'src'],
collectCoverageFrom: ['src/**/*.ts'],
coveragePathIgnorePatterns: ['__mocks__'],
moduleNameMapper: {
'^uxp$': '<rootDir>/../../dependency-mocks/uxp.js',
},
transformIgnorePatterns: ['/node_modules/(?!c2pa)/'],
globals: {
'ts-jest': {
babelConfig,
},
tsConfig: {
declaration: false,
},
PLUGIN_REV: '__pluginRev__',
},
setupFilesAfterEnv: ['./tests/test.setup.js'],
};
I also tried a babel plugin that is mentioned in the linked SO question.
"env": {
"test": {
"plugins": ["#babel/plugin-transform-modules-commonjs"]
}
},
I'm not sure if there's any other jest of babel config I might be missing here. Clearly something is wrong!

Aside from ignorePattern, I also updated preset:
preset: 'ts-jest/presets/js-with-ts',
The babel config changes were not necessary at all.

node-fetch 3.0.0 and jest gives SyntaxError: Cannot use import statement outside a module

I'm trying to upgrade my api to use node-fetch 3.0.0. Part of the breaking changes in their documentation is that node-fetch is now a pure ESM module.
https://github.com/node-fetch/node-fetch/blob/main/docs/CHANGELOG.md
My unit tests have started breaking from this change. I was using jest.requireActual("node-fetch") for the Response object
const { Response } = jest.requireActual("node-fetch");
However, with the new change, I get:
"Property 'Response' does not exist on type '{}'."
I tried changing to an import statement which seems to fix that error:
import { Response } from "node-fetch"
Now, I get the following error when I run my unit tests:
Test suite failed to run
Jest encountered an unexpected token
This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.
By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".
Here's what you can do:
• If you are trying to use ECMAScript Modules, see https://jestjs.io/docs/en/ecmascript-modules for how to enable it.
• 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/en/configuration.html
Details:
C:\Users\{mypath}\api\node_modules\node-fetch\src\index.js:9
import http from 'http';
^^^^^^
SyntaxError: Cannot use import statement outside a module
2 | import { AuthProvider, TokenCache } from "./tokenTypes";
3 | import { getUserEmail, getUserId, getUserRole } from "../common/authUtil";
> 4 | import fetch from "node-fetch";
The error seems to be occurring within node-fetch itself.
I tried changing the test script in my package.json to match what the jest documentation suggests for ESM modules. https://jestjs.io/docs/ecmascript-modules
package.json
"test": "node --experimental-vm-modules node_modules/jest/bin/jest.js"
The documentation also suggests changing the transform property in jest.config.js to take an empty object, but my transform object looks like the following for typescript and ts-jest:
jest.config.js
transform: { "^.+\\.ts?$": "ts-jest" }
If I change this to an empty object all of my tests break. I'm not very familiar with CJS vs ESM, so any help would be appreciated.

Fetch 3.0 is designed for using esmodules instead of commonjs. Therefore you have to make sure you import it into a module.
For example: to import it to app.js : Add "type":"module" in your package.json and then import it.
For importing it to other files or app.js even, you can also change the extension from .js to mjs that will tell nodejs to treat as a esmodule.
Otherwise downgrade fetch to use an older version that supports commonjs like 2.something.
npm install node-fetch#2
npm install #types/node-fetch#2

I had the same problem!
adding
transform: {
"^.+\\.(ts|tsx)$": "ts-jest",
"^.+\\.(js)$": "babel-jest",
},
transformIgnorePatterns: [
],
to my jest.config.js file solved it.
and btw these are my versions:
"jest": "^27.3.1",
"ts-jest": "^27.0.7",
"node-fetch": "^3.1.0"

"SyntaxError: Cannot use import statement outside a module" when importing a module which imports a module for side effects in Jest

I'm trying to use Jest to test some TS code I've written. I need this code to work on older browsers so am importing some polyfills and such for side effects.
My code looks something like this (variables changed to be more generic):
src/my_code.ts
import i18next from "i18next";
import Backend from 'i18next-http-backend';
import "promise-polyfill/src/polyfill";
var someVar = 12;
export function someFunc() {
return someVar + 1;
}
And my test looks something like this:
test/my_code.test.ts
import { someFunc } from '../src/my_code';
describe('some test case', function () {
console.log(someFunc());
});
I think my package.json and jest.config.js are okay, but running the test gives:
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.
• 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:
my_code/node_modules/promise-polyfill/src/polyfill.js:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,jest){import Promise from './index';
^^^^^^
SyntaxError: Cannot use import statement outside a module
1 | import i18next from "i18next";
2 | import Backend from 'i18next-http-backend';
> 3 | import "promise-polyfill/src/polyfill";
| ^
at Runtime.createScriptFromCode (node_modules/jest-runtime/build/index.js:1479:14)
at Object.<anonymous> (src/my_code.ts:3:1)
Test Suites: 1 failed, 1 total
Tests: 0 total
Snapshots: 0 total
Time: 1.701 s
Ran all test suites.
npm ERR! Test failed. See above for more details.
The other modules I've imported in my source work, but these are using the import x from "y"; syntax rather than import "z"; for side effects.
Anything here I could try?
EDIT: Added jest.config.js below:
module.exports = {
transform: { '^.+\\.ts?$': 'ts-jest' },
testEnvironment: 'node',
testRegex: '/test/.*\\.(test|spec)?\\.(ts|tsx)$',
moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node']
};

Come on brotha, please show me yow jest.config file also yow app works with them import statements, bcuz there might be something bundling yow code up to a point it is understandable to the environment it runs, but on the other head you is running them tests files with nodejs and as you already see, node doesn’t understand that, plus adding the fact that them test cases are written in ts instead of js, try this first, if it doesn’t work I’ll need yow jest config.
Install ts-node.
If you want to execute some ts code ether you need yo compile them files first or you can install ts-node
npm i -D ts-node.
To run them tests you need ts-node ./path-to-yow-file.
I think there is already a package call ts-jest

Jest React Native Expo.fx.js encountered an unexpected token

This is from the boilerplate Expo app built with create-react-native-app
Here's the jest section of my package.json:
"jest": {
"preset": "react-native",
"testEnvironment": "node"
},
Here's the output when I attempt to run jest:
> jest
FAIL src/__tests__/App.js
● Test suite failed to run
Jest encountered an unexpected token
This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.
By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".
Here's what you can do:
• 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/en/configuration.html
Details:
/home/charney/om/star-harvester-centauri/node_modules/expo/build/Expo.fx.js:1
import './environment/react-native-logs.fx';
^^^^^^
SyntaxError: Cannot use import statement outside a module
at Runtime._execModule (node_modules/jest-runtime/build/index.js:1157:58)
at Object.<anonymous> (node_modules/expo/src/Expo.ts:1:1)

Same answer as Jest encountered an unexpected token with react-native
"jest": {
"preset": "react-native",
"transform": {
"^.+\\.js$": "<rootDir>/node_modules/react-native/jest/preprocessor.js" },
"testEnvironment": "node"
},

Webpack can't find import needed for Typescript type resolution. How to fix this?

My project uses typescript and built with webpack.
I have a typings file that comes from a third part lib located under node_modules/#types/libname/custom.d.ts. That file has a namespace declaration with a few types in it:
declare namespace MyNamespace {
export type A = ...;
}
Then in order to be able to use that type in my typescript code like so:
const x: MyNamespace.A;
...I need to add the import declaration as follows somewhere in the app:
import 'libname'
Which tsc resolves correctly to node_modules/#types/libname/custom.d.ts so everything works if I compile with tsc.
However webpack then can't build. It can't understand this import:
ERROR in ./Index.tsx
Module not found: Error: Can't resolve 'libname' in 'C:\<path_to_index_file>'
# ./Index.tsx 44:0-32
I tried to add an alias in my webpack.config like so:
resolve: {
alias: Object.assign({
'libname$': path.resolve(__dirname, 'node_modules/#types/libname/custom.d.ts'),
}
},
But then it fails because it can't understand that file's syntax and asks if I'm missing a loader.
How can I fix this so that webpack will understand this typings import statement?
I'm on webpack version 4.41.6
Thanks!

You should use the null-loader for this import so webpack will ignore it.