title: How to avoid transforming test file in JS format?
body: <p>My project is using <code>ts-jest</code> as jest preset and i have some legacy test file which are still in <code>.js</code> format. I have grouped them under <code>test-backup</code> folder but I would still want to run the test.</p>
  <pre class="lang-js prettyprint-override"><code>/** @type {import('ts-jest/dist/types').InitialOptionsTsJest} */
  module.exports = {
    preset: 'ts-jest',
    testEnvironment: 'node',
    testPathIgnorePatterns: ['./node_modules/', '&lt;rootDir&gt;/dist/'],
    transformIgnorePatterns: ['&lt;rootDir&gt;/test-backup/.*/'],
  };
  </code></pre>
  <p>I've defined <code>transformIgnorePatterns</code> but seems like these <code>.js</code> files are still being transformed and I'm getting TypeError, wondering if anyone can share some idea to go about this?</p>