actionList.includes is not a function？

store.js方法：

actions: {
    async getBtnPermission({ commit }) {
      const res = await getBtnCode();
      const arr = res.split(',');
      console.log('按钮权限列表', arr);
      commit('updateBtnPerm', arr);
    },
  },

main.js内使用：

// 按钮权限指令
Vue.directive('has', {
  inserted: (el, binding) => {
    let actionList = store.dispatch('getBtnPermission');
    console.log('actionList', actionList);
    let values = binding.value;
    let hasPermission = actionList.includes(values);
    if (!hasPermission) {
      el.style = 'display:none';
      setTimeout(() => {
        el.parentNode.removeChild(el);
      }, 0);
    }
  },
});

为什么会报actionList.includes is not a function？