Function updateClassComponent

code/styling/public/app.js:9858–9889

(current, workInProgress, renderExpirationTime)

  }

  function updateClassComponent(current, workInProgress, renderExpirationTime) {
    // Push context providers early to prevent context stack mismatches.
    // During mounting we don't know the child context yet as the instance doesn't exist.
    // We will invalidate the child context in finishClassComponent() right after rendering.
    var hasContext = pushLegacyContextProvider(workInProgress);
    var shouldUpdate = void 0;
    if (current === null) {
      if (workInProgress.stateNode === null) {
        // In the initial pass we might need to construct the instance.
        constructClassInstance(workInProgress, workInProgress.pendingProps);
        mountClassInstance(workInProgress, renderExpirationTime);

        shouldUpdate = true;
      } else {
        // In a resume, we'll already have an instance we can reuse.
        shouldUpdate = resumeMountClassInstance(workInProgress, renderExpirationTime);
      }
    } else {
      shouldUpdate = updateClassInstance(current, workInProgress, renderExpirationTime);
    }

    // We processed the update queue inside updateClassInstance. It may have
    // included some errors that were dispatched during the commit phase.
    // TODO: Refactor class components so this is less awkward.
    var didCaptureError = false;
    var updateQueue = workInProgress.updateQueue;
    if (updateQueue !== null && updateQueue.capturedValues !== null) {
      shouldUpdate = true;
      didCaptureError = true;
    }
    return finishClassComponent(current, workInProgress, shouldUpdate, hasContext, didCaptureError, renderExpirationTime);
  }

  function finishClassComponent(current, workInProgress, shouldUpdate, hasContext, didCaptureError, renderExpirationTime) {
    // Refs should update even if shouldComponentUpdate returns false