title: Avoid require same things several times in several files
body: <p>I'm using <a href="https://jestjs.io/" rel="nofollow noreferrer">Jest</a> as test runner for Google Puppeteer.</p>
  
  <p>In Jest, a <code>file.test.js</code> is a suite of tests.</p>
  
  <p>For running tests, I need to require some libraries.</p>
  
  <p>A lot of tests require the same libraries.</p>
  
  <p>Can I avoid requiring these libraries in every test file? I would like to import once somewhere and use everywhere.</p>
  
  <p>e.g.</p>
  
  <ul>
  <li><code>test1.test.js</code> contains <code>const path = require('path')</code></li>
  <li><code>test2.test.js</code> contains <code>const path = require('path')</code></li>
  </ul>
  
  <p>I would like to write <code>const path = require('path')</code> once somewhere and use in <code>test1.test.js</code> and <code>test2.test.js</code>. I would like to do this both for <code>node_modules/</code> and for custom modules.</p>