Function flushSchedulerQueue

static/vuejs/vue.esm.js:2309–2366

* Flush both queues and run the watchers.

()

 * Flush both queues and run the watchers.
 */
function flushSchedulerQueue () {
  flushing = true;
  var watcher, id, vm;

  // Sort queue before flush.
  // This ensures that:
  // 1. Components are updated from parent to child. (because parent is always
  //    created before the child)
  // 2. A component's user watchers are run before its render watcher (because
  //    user watchers are created before the render watcher)
  // 3. If a component is destroyed during a parent component's watcher run,
  //    its watchers can be skipped.
  queue.sort(function (a, b) { return a.id - b.id; });

  // do not cache length because more watchers might be pushed
  // as we run existing watchers
  for (index = 0; index < queue.length; index++) {
    watcher = queue[index];
    id = watcher.id;
    has[id] = null;
    watcher.run();
    // in dev build, check and stop circular updates.
    if (process.env.NODE_ENV !== 'production' && has[id] != null) {
      circular[id] = (circular[id] || 0) + 1;
      if (circular[id] > config._maxUpdateCount) {
        warn(
          'You may have an infinite update loop ' + (
            watcher.user
              ? ("in watcher with expression \"" + (watcher.expression) + "\"")
              : "in a component render function."
          ),
          watcher.vm
        );
        break
      }
    }
  }

  // reset scheduler before updated hook called
  var oldQueue = queue.slice();
  resetSchedulerState();

  // call updated hooks
  index = oldQueue.length;
  while (index--) {
    watcher = oldQueue[index];
    vm = watcher.vm;
    if (vm._watcher === watcher && vm._isMounted) {
      callHook(vm, 'updated');
    }
  }

  // devtool hook
  /* istanbul ignore if */
  if (devtools && config.devtools) {
    devtools.emit('flush');
  }
}