Turborepo / Jest - Unable to transpile external ESM package

Question

Issue

Unable to transpile external package exported in ESM syntax

Jest Version

29.5.0

Steps to reproduce

1. Clone my repo at https://github.com/paulwongx/turborepo-jest-issue
2. Install packages yarn workspace jest-issue install
3. Run the test yarn workspace jest-issue test example

Expected behavior

I expect to have the test compile, run and pass

Actual behavior

Jest encounters an unexpected token (see below)

`Jest encountered an unexpected token`
    /Users/.../turborepo_jest_issue/node_modules/oauth4webapi/build/index.js:7
    export const clockSkew = Symbol();
    ^^^^^^

    SyntaxError: Unexpected token 'export'

    > 1 | import * as o from "oauth4webapi";
        | ^
      2 |
      3 | export const value = o.skipStateCheck;

Additional context

• @babel/plugin-transform-modules-commonjs in .babelrc isn't working to convert the esm exports in the external package build file
• transformIgnorePatterns in jest.config.ts isn't working to transform the external package

Environment

System:
    OS: macOS 13.4
    CPU: (4) x64 Intel(R) Core(TM) i5-7360U CPU @ 2.30GHz
  Binaries:
    Node: 16.14.2 - /usr/local/bin/node
    Yarn: 1.22.18 - /usr/local/bin/yarn
    npm: 8.5.0 - /usr/local/bin/npm

jest.config.ts

import type {Config} from 'jest';
import path from 'path';

const config: Config = {
  testEnvironment: 'jsdom',
  transform: {
    '^.+\\.(js|jsx)$': 'babel-jest',
    '^.+\\.(ts|tsx)$': 'ts-jest',
  },
  moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node'],
  "transformIgnorePatterns": [
    `${path.join(process.cwd(), "../..")}/node_modules/(?!(oauth4webapi))`,
  ],
};

export default config;

.babelrc

{
  "env": {
    "test": {
      "plugins": ["@babel/plugin-transform-modules-commonjs"]
    }
  }
}

example.ts

import * as o from "oauth4webapi";

export const value = o.skipStateCheck;

example.spec.ts

import {value} from "./example";

describe("example", () => {
  it("should be true", () => {
    expect(value).toBe(true);
  });
});

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