Unit testing 使用VueJs测试令牌解码的Jest

我有一个方法可以接受这样的请求：

{"token_type":"Bearer",
"expires_in":36000,
"access_token":"blabla",
"refresh_token":"blablbla"}

loginSuccessful (req) {
    const jwtDecode = require('jwt-decode')
    const decoded = jwtDecode(req.data.access_token)
    const role = decoded.scopes[0]
    this.toktok = req.data.access_token
    localStorage.role = role
    localStorage.token = req.data.access_token
    localStorage.refresh_token = req.data.refresh_token
  },

该方法使用jwt解码令牌，并将信息存储在本地存储器中 当我尝试测试此功能时：

it('Mounting Login successfully Method', () => {

    const response = {
      data:
        {
          token_type: 'Bearer',
          expires_in: 36000,
          access_token: 'dsqdsq',
          refresh_token: 'dqsdqs',}
      ,
    }
    const wrapper = mount(Login, {
      localVue,
      sync: false,
    })
    wrapper.vm.loginSuccessful(response)
    expect(localStorage.getItem('token')).toEqual(response.data.access_token)
    expect(localStorage.getItem('refresh_token')).toEqual(response.data.refresh_token)
  })

我得到一个错误，解码是未定义的