How do I return the clientWidth or clientHeight with capybara?

Question

I'm currently using capybara and capybara-webkit and can correctly render the page as a PNG and access the DOM. However, I can't seem to get the actual render width of the element. Is this possible?

To be clear, I'm trying to get the width in pixels that would be returned if I had typed

document.getElementById('myelement').clientWidth

in Chrome Developer Tools or Firebug.

Answer 1

I managed to figure this out myself! page.evaluate_script is the answer.