textarea-insert-from-drop-type-input-event-data.html

<!DOCTYPE html>
<html>
<body>
<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<textarea id="text" cols="60">Dragging and dropping text should set
  the event.data with the text for inputType insertFromDrop</textarea>
<script>
  const text = document.getElementById("text");
  let eventData;
  text.addEventListener('input', (evt) => {
    if(evt.inputType == 'insertFromDrop')
      eventData = evt.data;
  });
  test(function () {
    text.focus();
    // Selecting first word of the text.
    text.setSelectionRange(0, 8);
    const selectedData = getSelection().toString();
    // Note drag and drop doesn't work well with pointerActionSequence, so using
    // eventSender.

    // Move mouse to the start of the text.
    eventSender.mouseMoveTo((text.offsetLeft + 10), text.offsetTop + 10);
    eventSender.mouseDown();
    eventSender.leapForward(500);
    // Move mouse to the end of the text.
    eventSender.mouseMoveTo(text.offsetLeft + text.offsetWidth - 10 , text.offsetTop + 10);
    eventSender.mouseUp();
    // Event data should now be set with the first word of the text
    // which is "Dragging".
    assert_equals(selectedData, "Dragging");
    assert_equals(eventData, selectedData);
  }, 'Input event data for inputType insertFromDrop should be set');
</script>
</body>
</html>

chromium/third_party/blink/web_tests/editing/input/textarea-insert-from-drop-type-input-event-data.html