teramako · December 18, 2015 16:59
diff --git a/page-nav.js b/page-nav.js
 "use strict";
 /**
 * :nav コマンドでテキトウに補完を使いましょう
 * :nnoremap v :nav<Space> とかすると快適かも
 */
 
 var selector = "h1, h2, h3, h4, main, [role=main], [role=navigation], [role=search]";
 var cache = new WeakMap;

 function getJumpList (force) {
  var browser = gBrowser.selectedBrowser,
      doc = browser.contentDocument,
      win = browser.contentWindow;

  if (!force && cache.has(win))
    return cache.get(win);

  var items = [];
  var wX = win.scrollX,
      wY = win.scrollY,
      index = 1;

  for (let elm of doc.querySelectorAll(selector)) {
    let id = elm.getAttribute("id") || "",
        role = elm.getAttribute("role") || "",
        rect = elm.getBoundingClientRect();

    let localName = elm.localName,
        key = index + ":" + localName + ":",
        desc = elm.textContent.substring(0, 50).replace(/\s+/g, " ");

    if (id)
      key += "#" + id + ":";
    if (role)
      key += "[" + role + "]:"

    items.push({
      id: id,
      key: key + desc,
      desc: localName + ": " + desc,
      x: wX + rect.left,
      y: wY + rect.top,
      node: elm,
    });
    index++;
  }
  cache.set(win, items);
  return items;
 }

 function jumpTo (item) {
  var win = gBrowser.contentWindow;
  if (item.id)
    win.location.hash = "#" + item.id;
  else
    win.scrollTo(Math.min(item.x, win.scrollMaxX), Math.min(item.y, win.scrollMaxY));

  item.node.focus();
  flashNode(item.node);
  cache.delete(win);
 }

 function flashNode (node) {
  var count = 7,
      originalOUtline = node.style.outline,
      win = node.ownerDocument.defaultView;

  var id = win.setInterval(function(){
    if (count <= 0) {
      win.clearInterval(id);
      node.style.outline = originalOUtline;
      return;
    }
    node.style.outline = count % 2 ?
                         "2px solid red":
                         "0 solid transparent";
    --count;
  }, 200);
 }

 commands.addUserCommand(["nav"], "page jump",
  function (args) {
    var list = getJumpList();
    var arg = args.string;
    var m = arg.match(/^(\d+):?/);
    if (m) {
      let index = parseInt(m[1], 10) - 1;
      if (index in list) {
        jumpTo(list[index]);
        return;
      }
    }
    var item = list.filter(function (item) {
      return item.key.contains(arg);
    })[0];
    if (item)
      jumpTo(item);
  }, {
    literal: 0,
    completer: function (context) {
      context.title = ["Page Jump List"];
      context.compare = CompletionContext.Sort.unsorted;
      context.anchored = false;
      context.completions = [[item.key, item.desc] for (item of getJumpList(true))];
    },
  }, true);