react函数组件卸载问题

Question

function commitUnmount(
  finishedRoot: FiberRoot,
  current: Fiber,
  nearestMountedAncestor: Fiber,
): void {
  onCommitUnmount(current);
  switch (current.tag) {
    case FunctionComponent:
    case ForwardRef:
    case MemoComponent:
    case SimpleMemoComponent: {
      const updateQueue: FunctionComponentUpdateQueue | null = (current.updateQueue: any);
      if (updateQueue !== null) {
        const lastEffect = updateQueue.lastEffect;
        if (lastEffect !== null) {
          const firstEffect = lastEffect.next;

          let effect = firstEffect;
          do {
            const {destroy, tag} = effect;
            if (destroy !== undefined) {
              if ((tag & HookLayout) !== NoHookEffect) {
                if (
                  enableProfilerTimer &&
                  enableProfilerCommitHooks &&
                  current.mode & ProfileMode
                ) {
                  startLayoutEffectTimer();
                  safelyCallDestroy(current, nearestMountedAncestor, destroy);
                  recordLayoutEffectDuration(current);
                } else {
                  safelyCallDestroy(current, nearestMountedAncestor, destroy);
                }
              }
            }
            effect = effect.next;
          } while (effect !== firstEffect);
        }
      }
      return;
    }
    ...
}

class FriendStatusWithCounter extends React.Component {
  constructor(props) {
    super(props);
    this.state = { count: 0, isOnline: null };
    this.handleStatusChange = this.handleStatusChange.bind(this);
  }

  componentDidMount() {
    document.title = `You clicked ${this.state.count} times`;
    ChatAPI.subscribeToFriendStatus(
      this.props.friend.id,
      this.handleStatusChange
    );
  }

  componentDidUpdate() {
    document.title = `You clicked ${this.state.count} times`;
  }

  componentWillUnmount() {
    ChatAPI.unsubscribeFromFriendStatus(
      this.props.friend.id,
      this.handleStatusChange
    );
  }
  ...
}

我看react文档介绍useEffect类比类组件用法，类组件在componentWillUnmount会执行useEffect的销毁机制，但函数组件却好像只在更新时执行销毁机制然后重新执行passive effect。react的函数组件被卸载时不需要调用passive effect的销毁机制吗？为什么只判断有没有layout effect（tag & HookLayout !== NoHookEffect）而不需要判断HookPassive？求大佬帮我解答困惑。