此文中的可能，只是在看源码时的记录笔记，暂时没有解决。

中断的可能

React-recociler中的参数可分为基础的、Mutation(变化)、Persistence(持续；固执；存留)、Hydration(水合作用)。

  1. // 下面标识了中断的可能
  2. function stopWorkLoopTimer(interruptedBy, didCompleteRoot) {
  3.   if (enableUserTimingAPI) {
  4.     if (!supportsUserTiming) {
  5.       return;
  6.     }
  7.     var warning = null;
  8.     if (interruptedBy !== null) {
  9.       if (interruptedBy.tag === HostRoot) {
  10.         warning = 'A top-level update interrupted the previous render';//@中断可能一
  11.       } else {
  12.         var componentName = getComponentName(interruptedBy.type) || 'Unknown';
  13.         warning = 'An update to ' + componentName 
  14.           + ' interrupted the previous render';//@中断可能二
  15.       }
  16.     } else if (commitCountInCurrentWorkLoop > 1) {
  17.       warning = 'There were cascading updates';
  18.     }
  19.     commitCountInCurrentWorkLoop = 0;
  20.     var label = didCompleteRoot ? 
  21.         '(React Tree Reconciliation: Completed Root)' : '(React Tree Reconciliation: Yielded)';
  22.     // Pause any measurements until the next loop.
  23.     pauseTimers();
  24.     endMark(label, '(React Tree Reconciliation)', warning);
  25.   }
  26. }

延迟执行

  1. if (finishedWork !== null) {
  2.   // We've completed the root. Commit it.
  3.   completeRoot(root, finishedWork, expirationTime);
  4. }

在completeRoot 中有一段代码，可阻止当前提交，等待下一次提价的：

  1. function completeRoot(root: FiberRoot, finishedWork: Fiber, 
  2.                        expirationTime: ExpirationTime): void {
  3.   // Check if there's a batch that matches this expiration time.
  4.   const firstBatch = root.firstBatch;
  5.   if (firstBatch !== null && firstBatch._expirationTime >= expirationTime) {
  6.     if (completedBatches === null) {
  7.       completedBatches = [firstBatch];
  8.     } else {
  9.       completedBatches.push(firstBatch);
  10.     }
  11.     if (firstBatch._defer) {// 阻止提交
  12.       // This root is blocked from committing by a batch. Unschedule it until
  13.       // we receive another update.
  14.       root.finishedWork = finishedWork;
  15.       root.expirationTime = NoWork;
  16.       return;
  17.     }
  18.   }
  19.   // ...
  20.   commitRoot(root, finishedWork);
  21. }

firstBatch._defer 为true，可阻止提交。
firstBatch._defer 为true就阻止本次提交并等待下一次提交。查了查代码，发现 _defer 是在 ReactDOM 源码中packages\react-dom\src\client\ReactDOM.js 中 ReactBatch，代码如下：

  1. function ReactBatch(root: ReactRoot) {
  2.   const expirationTime = computeUniqueAsyncExpiration();
  3.   this._expirationTime = expirationTime;//设置的时间
  4.   this._root = root;
  5.   this._next = null;
  6.   this._callbacks = null;
  7.   this._didComplete = false;
  8.   this._hasChildren = false;
  9.   this._children = null;
  10.   this._defer = true;//初始设置为true
  11. }
  12. /**此处的重点不在这，省略....代码*/