SyntaxError: Cannot use import statement outside a module, with TypeScript and ES Modules

🐛 Bug Report

Filing a separate issue at @SimenB’s suggestion.

After following the steps to get native ESM support, I’m running into the following error in a project that transpiles TypeScript files using @babel/preset-typescript:

/home/dandv/jets/lib.test.ts:1
import { foo } from './lib';
^^^^^^

SyntaxError: Cannot use import statement outside a module

  at Runtime._execModule (node_modules/jest-runtime/build/index.js:1074:58)

To Reproduce

1. git clone https://github.com/dandv/jest-typescript-es-modules.git
2. cd jest-typescript-es-modules
3. npm install
4. npm test

Expected behavior

Test passes.

Link to repl or repo (highly encouraged)

https://github.com/dandv/jest-typescript-es-modules

envinfo

System:
    OS: Linux 5.3 Ubuntu 18.04.4 LTS (Bionic Beaver)
    CPU: (8) x64 Intel(R) Core(TM) i7-8665U CPU @ 1.90GHz
  Binaries:
    Node: 13.13.0 - /usr/bin/node
    npm: 6.14.4 - ~/.local/bin/npm
  npmPackages:
    jest: ^25.4.0 => 25.4.0

[mnajjarian]

I had the same problem. I’ve fixed that by including js files in ts-node:

"transform": { "^.+\\.(ts|tsx|js|jsx)?$": "ts-jest" }

[GeoffreyBooth]

What I’m thinking makes sense is to make that last one behave like js, i.e. infer from the type field.

Hi, I stumbled across this issue and thought I’d say hi. I’m the maintainer of CoffeeScript and I’ve been dealing with this same issue. In my case, there are plenty of legacy .coffee files out there that use require/CommonJS, including the CoffeeScript codebase itself. My plan is to treat .coffee as equivalent to .js, as in, “behave however a .js file would at this path”—so if it’s in a "type": "module" package scope, it’s ESM. I think that’s the safest approach; even if you think all TypeScript you’ll ever encounter uses import/export, I wouldn’t be surprised if there are some folks out there who have been mixing import and require statements occasionally, since presumably they currently work.