useQuery does not return data on refetch after error.

Steps to reproduce:

1. Make a successful request
2. Take graphql server offline
3. Make a new request
4. We get an error now.
5. Take graphql server online
6. Invoke refetch.
7. Note the successful network request in devtools, but we never get data back from useQuery.

[gregbty]

I’m assuming a PR is still needed for this? Running into this issue now and it is still unresolved in react-apollo so thought it would probably be easier to apply the workaround above in this repo. I can open one if needed.

[maxguzenski]

I was able to solve the problem based on https://github.com/apollographql/react-apollo/blob/master/src/Query.tsx#L363

changing useEffect inside useQuery by:

  useEffect(() => {
    if (!watchedQuery) {
      return 
    }

    let subscription

    // if fetchPolicy='cache-and-network' and data is on cache
    // notifyOnNetworkStatusChange is aways TRUE, why?? 
    // this "if" fix it.
    function invalidateCurrentResult(props) {
      if (props.loading) return
      setResponseID(x => x + 1)
    } 

    // from: https://github.com/apollographql/react-apollo/blob/master/src/Query.tsx#L363
    // after a error on refetch, without this fix, refetch never works again
    function invalidateErrorResult() {
      unsubscribe()

      const lastError  = watchedQuery.getLastError()
      const lastResult = watchedQuery.getLastResult()

      watchedQuery.resetLastResults()
      subscribe() 

      Object.assign(watchedQuery, { lastError, lastResult })
      setResponseID(x => x + 1)
    }
    
    function subscribe() {
      subscription = watchedQuery.subscribe(
        invalidateCurrentResult,
        invalidateErrorResult
      )
    }

    function unsubscribe() {
      if (subscription) subscription.unsubscribe() 
      subscription = undefined
    }

    subscribe()
    return unsubscribe

  }, [watchedQuery])