Function ensureRootIsScheduled

docs/index.js:14822–14832

(root)

  isFlushingWork = !1,
  currentEventTransitionLane = 0;
function ensureRootIsScheduled(root) {
  root !== lastScheduledRoot &&
    null === root.next &&
    (null === lastScheduledRoot
      ? (firstScheduledRoot = lastScheduledRoot = root)
      : (lastScheduledRoot = lastScheduledRoot.next = root));
  mightHavePendingSyncWork = !0;
  didScheduleMicrotask ||
    ((didScheduleMicrotask = !0),
    scheduleImmediateTask(processRootScheduleInMicrotask));
}
function flushSyncWorkAcrossRoots_impl(syncTransitionLanes, onlyLegacy) {
  if (!isFlushingWork && mightHavePendingSyncWork) {
    isFlushingWork = !0;