Testing hover style CSS changes with 'vue-test-utils'

I'd like to write tests for a Vue component which looks something like this

HTML

<div>
  <div class="root">
    Hover here.
  </div>
  <div class="tooltip">
    Tooltip content
  </div>
</div>

CSS

.tooltip { visibility: hidden; }
.root:hover + .tooltip { visibility: visible; }

So implementing a tooltip with CSS and not DOM events like mouseover and mouseout.

How could I trigger the hovering event using vue-test-utils ?