chromium/third_party/blink/web_tests/wpt_internal/forms/file/file-input-webkitdirectory-key-enter.html

<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<title>INPUT TYPE=FILE WEBKITDIRECTORY and key events - Enter key</title>
<input type="file" webkitdirectory>
<script type="module">
import {mockFileChooserFactory} from '../resources/mock-file-chooser.js';

promise_test(async _ => {
  const promise = new Promise(
      resolve => mockFileChooserFactory.addEventListener('open', resolve));

  const file = document.querySelector('input');
  file.focus();
  // Despite the name, 'keyDown' simulates a full down/press/up sequence.
  eventSender.keyDown('Enter', []);
  const openEvent = await promise;
  assert_equals(openEvent.detail, 'kUploadFolder');
}, 'pressing Enter with focus on a webkitdirectory file input element launches a file chooser');
</script>