Sandbox: https://codesandbox.io/s/cranky-kapitsa-op3jh

Repro: type "a" and then after a second "b"

Expected: Eventually you'll see "ab" in all fields. Pending "..." indicator goes away.

Actual: You'll keep seeing "a" in low pri field. Pending "..." indicator is stuck.
);
    currentHook = nextCurrentHook;
    const newHook: Hook = {
      memoizedState: currentHook.memoizedState,
      baseState: currentHook.baseState,
      baseQueue: currentHook.baseQueue,
      queue: currentHook.queue,
      next: null,
    };
    if (workInProgressHook === null) {
      
      currentlyRenderingFiber.memoizedState = workInProgressHook = newHook;
    } else {
      
      workInProgressHook = workInProgressHook.next = newHook;
    }
  }
  return workInProgressHook;
}
function createFunctionComponentUpdateQueue(): FunctionComponentUpdateQueue {
  return {
    lastEffect: null,
  };
}
function basicStateReducer<S>(state: S, action: BasicStateAction<S>): S {
  
  return typeof action === 'function' ? action(state) : action;
}
function mountReducer<S, I, A>(
  reducer: (S, A) => S,