Fix aggregation on custom data

See: #64 (closed)

This might be the fix but something in me tells me there is a more elegant solution possible. I will have a look at another time at this

ps. My personal opinion is that under the hood the data processor extension is too complex.

I agree. I was not sure how to approach this. Since custom fields have their own specification, I almost went for a new aggregation custom fields specification, however that seemed over kill for modifying one string.

Fixed with another fix. One was by using the function getName in AggregateFunctionFieldSpecification::convertFromFieldSpecification

And the other fix was an issue with name the subquery data flow in the contribution data source.

closed

Fantastic!