170. Generate CSS Selector for target element

Given a DOM tree and a target element, generate a valid selector to target it.

For example, for a DOM tree like below

<div>
  <p>BFE.dev</p>
  <div>
    is
    <p>
      <span>great. <button>click me!</button></span>
    </p>
  </div>
</div>

There could be more than 1 answer.

let selector = generateSelector(root, target) // 'button'
expect(root.querySelector(selector)).toBe(target)

selector = generateSelector(root, target) // 'div > div > p > button'
expect(root.querySelector(selector)).toBe(target)