isPureView()的Component的shouldUpdate()不会被调用

[niechaoqun9456]

  bool isPureView() {
    return protectedReducer == null &&
        protectedEffect == null &&
        protectedDependencies == null;
  }

reducer、effect、dependencies都为null时，Compenent isPureView()=true。

  @override
  Widget buildComponent(
    Store<Object> store,
    Get<Object> getter, {
    @required DispatchBus bus,
    @required Enhancer<Object> enhancer,
  }) {
    /// Check bus: DispatchBusDefault(); enhancer: EnhancerDefault<Object>();
    assert(bus != null && enhancer != null);

    return protectedWrapper(
      isPureView()
          ? _PureViewWidget<T>(
              store: store,
              viewBuilder: enhancer.viewEnhance(protectedView, this, store),
              getter: getter,
              bus: bus,
            )
          : ComponentWidget<T>(
              component: this,
              getter: _asGetter<T>(getter),
              store: store,
              key: key(getter()),
              bus: bus,
              enhancer: enhancer,
            ),
    );
  }

shouldUpdate只有当Component的isPureView()=false时才会起作用。

  @override
  void didUpdateWidget() {
    final T now = state;
    if (shouldUpdate(_latestState, now)) {
      _widgetCache = null;
      _latestState = now;
    }
  }

  @override
  void onNotify() {
    final T now = state;
    if (shouldUpdate(_latestState, now)) {
      _widgetCache = null;

      markNeedsBuild();

      _latestState = now;
    }
  }

这样的话，每次State变化，pureView Component都会无条件buildView。
请问是有意这样设计的吗？如果是，这样设计的原因是什么？