Function startObserving

index.js:162–235

(document)

    };

    function startObserving(document) {
      var connected = new WeakSet();
      var disconnected = new WeakSet();

      try {
        new MutationObserver(changes).observe(document, {
          subtree: true,
          childList: true
        });
      } catch (o_O) {
        var timer = 0;
        var records = [];

        var reschedule = function reschedule(record) {
          records.push(record);
          clearTimeout(timer);
          timer = setTimeout(function () {
            changes(records.splice(timer = 0, records.length));
          }, 0);
        };

        document.addEventListener('DOMNodeRemoved', function (event) {
          reschedule({
            addedNodes: [],
            removedNodes: [event.target]
          });
        }, true);
        document.addEventListener('DOMNodeInserted', function (event) {
          reschedule({
            addedNodes: [event.target],
            removedNodes: []
          });
        }, true);
      }

      function changes(records) {
        for (var record, length = records.length, i = 0; i < length; i++) {
          record = records[i];
          dispatchAll(record.removedNodes, 'disconnected', disconnected, connected);
          dispatchAll(record.addedNodes, 'connected', connected, disconnected);
        }
      }

      function dispatchAll(nodes, type, wsin, wsout) {
        for (var node, event = new Event(type), length = nodes.length, i = 0; i < length; (node = nodes[i++]).nodeType === 1 && dispatchTarget(node, event, type, wsin, wsout)) {
        }
      }

      function dispatchTarget(node, event, type, wsin, wsout) {
        if (observer.has(node) && !wsin.has(node)) {
          wsout["delete"](node);
          wsin.add(node);
          node.dispatchEvent(event);
          /*
          // The event is not bubbling (perf reason: should it?),
          // hence there's no way to know if
          // stop/Immediate/Propagation() was called.
          // Should DOM Level 0 work at all?