template/src/transforms/code.js

import Prism from 'prismjs';

export default function(dom, data) {
  let codeElements = [].slice.call(dom.querySelectorAll('dt-code'));
  codeElements.forEach(el => {
    let content = el.textContent;
    el.innerHTML = '';
    let language = el.getAttribute('language');
    let c = dom.createElement('code');
    if (el.getAttribute('block') === '') {
      // Let's normalize the tab indents
      content = content.replace(/\n/, '');
      let tabs = content.match(/\s*/);
      content = content.replace(new RegExp('\n' + tabs, 'g'), '\n');
      content = content.trim();
      let p = dom.createElement('pre');
      p.appendChild(c);
      el.appendChild(p);
    } else {
      el.appendChild(c);
    }
    let highlighted = content;
    if (Prism.languages[language]) {
      c.setAttribute('class', 'language-' + language);
      highlighted = Prism.highlight(content, Prism.languages[language]);
    }
    c.innerHTML = highlighted;
  });
}