Function renderRoot

code/communication/public/app.js:13300–13377

(root, expirationTime, isAsync)

  }

  function renderRoot(root, expirationTime, isAsync) {
    !!isWorking ? invariant(false, 'renderRoot was called recursively. This error is likely caused by a bug in React. Please file an issue.') : void 0;
    isWorking = true;

    // Check if we're starting from a fresh stack, or if we're resuming from
    // previously yielded work.
    if (expirationTime !== nextRenderExpirationTime || root !== nextRoot || nextUnitOfWork === null) {
      // Reset the stack and start working from the root.
      resetStack();
      nextRoot = root;
      nextRenderExpirationTime = expirationTime;
      nextUnitOfWork = createWorkInProgress(nextRoot.current, null, nextRenderExpirationTime);
      root.pendingCommitExpirationTime = NoWork;
    }

    var didFatal = false;

    startWorkLoopTimer(nextUnitOfWork);

    do {
      try {
        workLoop(isAsync);
      } catch (thrownValue) {
        if (nextUnitOfWork === null) {
          // This is a fatal error.
          didFatal = true;
          onUncaughtError(thrownValue);
          break;
        }

        if (true && replayFailedUnitOfWorkWithInvokeGuardedCallback) {
          var failedUnitOfWork = nextUnitOfWork;
          replayUnitOfWork(failedUnitOfWork, isAsync);
        }

        var sourceFiber = nextUnitOfWork;
        var returnFiber = sourceFiber['return'];
        if (returnFiber === null) {
          // This is a fatal error.
          didFatal = true;
          onUncaughtError(thrownValue);
          break;
        }
        throwException(returnFiber, sourceFiber, thrownValue);
        nextUnitOfWork = completeUnitOfWork(sourceFiber);
      }
      break;
    } while (true);

    // We're done performing work. Time to clean up.
    stopWorkLoopTimer(interruptedBy);
    interruptedBy = null;
    isWorking = false;

    // Yield back to main thread.
    if (didFatal) {
      // There was a fatal error.
      {