Settle Feuds with Data

[danReynolds]

Ran into a scenario as described by @benjamn here: https://github.com/apollographql/apollo-client/blob/master/src/core/QueryInfo.ts#L237

where queries were feuding over a piece of data in the cache, causing an infinite loop of network requests. Normally this mechanism would have prevented them from continuing on in that loop because they were returning the same network result data every time, however, our Apollo server has tracing extensions applied as described here: https://github.com/apollographql/apollo-tracing

which causes this check to fail:
https://github.com/apollographql/apollo-client/blob/master/src/core/QueryInfo.ts#L238

since the result objects include the extensions and the extensions include unique time sensitive data like query durations and start/end time. The simple fix is to check for equality of the data properties of the results rather than the entire result objects. If that has consequences I'm not aware of, then it might be better to check equality of the objects, omitting the extensions property.

[benjamn]

Great idea @danReynolds! It makes perfect sense to me to check only result.data, since that's all we're writing into the cache. Other result properties shouldn't be contributing to the problem that this logic is trying to prevent.

[xfournet]

Thanks @danReynolds! i was also fighting with the same problem and come to the same conclusion. Happy to see the fix is already available