title: How to find an image tag by filename using xpath
body: <p>I am running some cucumber features using capybara and I need to check if a certain image is being shown.</p>
  
  <p>I tried this xpath match but apparently the function <code>matches</code> is not available:</p>
  
  <pre><code>//img[matches(@src, "my_image.png")]
  </code></pre>