Can't use the package with Jest: SyntaxError: Cannot use import statement outside a module

[zaxovaiko]

Hey. I love your package since it helps me mock complicated data in just a few lines.

Besides using the package for generating mocked data, I decided to use it in my unit/integrational tests that I wrote using Jest. However, when I'm trying to import the createSeedClient, I get an error. Before running tests, I execute npx @snaplet/seed sync.

➜  ✗ npm run test

> api@1.0.0 test
> jest --coverage --verbose --detectOpenHandles --forceExit

TypeError: Jest: Got error running globalSetup - /Users/.../apps/api/src/lib/jest/setup.ts, reason: Unknown file extension ".ts" for /Users/.../apps/api/src/lib/jest/setup.ts
    at Object.getFileProtocolModuleFormat [as file:] (node:internal/modules/esm/get_format:160:9)
    at defaultGetFormat (node:internal/modules/esm/get_format:203:36)
    at defaultLoad (node:internal/modules/esm/load:143:22)
    at async ModuleLoader.load (node:internal/modules/esm/loader:409:7)
    at async ModuleLoader.moduleProvider (node:internal/modules/esm/loader:291:45)
    at async link (node:internal/modules/esm/module_job:76:21)
npm ERR! Lifecycle script `test` failed with error:
npm ERR! Error: command failed
npm ERR!   in workspace: api@1.0.0
npm ERR!   at location: /Users/.../apps/api

I tried literally everything, every combination of Jest configuration (esm), and read every documentation I ever could, but I still can't figure out how to fix that.

I'm not sure if the problem is directly related to your package rather than some limitations of the ts-jest library, but I hope you can direct me to the solution or at least a good idea of how to make a workaround for the problem.

package.json:

...
  "devDependencies": {
    "@snaplet/copycat": "5.0.0",
    "@snaplet/seed": "0.97.20",
    "@types/jest": "29.5.12",
    "jest": "29.7.0",
    "ts-jest": "29.2.3",
    "ts-node": "10.9.2",
    ...
  },

jest.config.ts:

...

const jestConfig: JestConfigWithTsJest = {
  testEnvironment: "node",
  preset: "ts-jest",
  rootDir: ".",
  globalSetup: "<rootDir>/src/lib/jest/setup.ts",
  globalTeardown: "<rootDir>/src/lib/jest/teardown.ts",
};

setup.js:

import Seed from "@snaplet/seed"; // here is the problem with an import

import { connectToDatabase, db } from "../database";

export default async function () {
  const seed = await Seed.createSeedClient({ dryRun: false });
  await connectToDatabase();
}

tsconfig.json:

{
  "$schema": "https://json.schemastore.org/tsconfig",
  "compilerOptions": {
    "rootDirs": ["src"],
    "outDir": "dist",
    "lib": ["es2020"],
    "target": "es2020",
    "module": "commonjs",
    "allowJs": true,
    "moduleResolution": "node",
    "types": ["node", "jest"],
    "strict": true,
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "skipLibCheck": true,
    "baseUrl": ".",
    "rootDir": ".",
    "paths": {
      "@/*": ["src/*"],
    }
  },
  "exclude": ["node_modules", "generated.ts"]
}