阿波罗链路状态在调用缓存时发出投诉。写入数据

ApolloError.js?f55daa5:36 Uncaught (in promise) Error: Network error: Cannot read property 'selections' of null
    at new ApolloError (ApolloError.js?f55daa5:36)
    at Object.error (QueryManager.js?8f5ff47:115)
    at SubscriptionObserver.error (zen-observable.js?8f5ff47:176)
    at <anonymous>

我的源代码如下:

{ // resolvers and defaults
  resolvers: {
    Mutation: {
      openModal: (_, args, { cache }) => {
        const {name} = args
        cache.writeData({
          modal: {
            name,
            open: true,
            __typename: 'Modal',
          },
        })
        return null
      },
      closeModal: (_, __, {cache}) => {
        cache.writeData({modal: {open: false}})
      }
    }
  },
  defaults: {
    modal: {
      __typename: 'Modal',
      open: false,
      name: ''
    }
  }
}

graphql(
    gql`
        mutation openModal  ($name: String!) {
            openModal  (name: $name) @client
        }
    `
  )(
  ({mutate}) => {
    return (
      <div>
        <button onClick={() => mutate({ variables: { name: 'test' }})} >Open</button>
      </div>
    )
  }
)

单击按钮时,会出现错误消息。有什么想法吗?

顺便说一句,我在next中使用。js。