rustdoc-condensed.js

(function() {
  /* This function forces rustdoc to collapse documentation for all items,
     except for the methods defined in an impl block and the primary type's
     declaration. This is the most natural view IMO, since it provides the
     primary type along with an easy to scan overview of available methods.
     
     rustdoc does seemingly have user settings that purport to make this the
     default, but I could never cause them to work in a reliably consistent
     way. This is especially useful when writing documents, where you commonly
     want to refresh and look at the docs for the specific item you're working
     on. This mini-script will automatically scroll to and expand the currently
     selected method.
     
     I used the tridactyl Firefox extension to bind this script to `,z` with
     the following in my tridactylrc:
     
         bind ,z composite jsb tri.native.run('cat path/to/rustdoc-condensed.js') | js -p eval(JS_ARG.content)

     get the currently selected doc item from URL's hash fragment
     e.g., in `struct.BStr.html#method.words`, this returns `method.words`.
  */
  function getPageId() {
    var id = document.location.href.split("#")[1];
    if (id) {
      return id.split("?")[0].split("&")[0];
    }
    return null;
  }

  /* collapse everything, with an extra click in case things are partially
     collapased already
  */
  const toggleAll = document.getElementById('toggle-all-docs');
  if (toggleAll.className.indexOf('will-expand') > -1) {
    toggleAll.click();
  }
  toggleAll.click();

  /* re-expand primary impls */
  const impls = document.getElementsByClassName('impl');
  for (let i = 0; i < impls.length; i++) {
    /* but don't expand every impl, just the ones on this type */
    if (!/^impl(-\d+)?$/.test(impls[i].id)) {
      continue;
    }

    const toggles = impls[i].getElementsByClassName('collapse-toggle');
    for (let j = 0; j < toggles.length; j++) {
      /* If it's already expanded, then let it be. In newer versions of
         rustdoc, collapsing everything doesn't collapse the methods, so we
         don't need to do anything.
      */
      if (toggles[j].innerText == '[−]') {
        continue;
      }
      toggles[j].click();
    }
  }

  /* expand type declaration docs */
  const main = document.getElementById('main');
  const wrapper = document.getElementsByClassName('toggle-wrapper')[0];
  wrapper.getElementsByTagName('a')[0].click();

  /* re-expand specific method declaration, and scroll to it */
  const pageId = getPageId();
  if (pageId !== null) {
    const method = document.getElementById(pageId);
    method.getElementsByClassName('collapse-toggle')[0].click();
    method.scrollIntoView();
  }
})()