Zachary Tong 715c90bf7d Aggs must specify a field or script (or both) (#52226)
This adds a validation to VSParserHelper to ensure that a field or
script or both are specified by the user.  This is technically
required today already, but throws an exception much deeper
in the agg framework and has a very unintuitive error for the user
(as well as eating more resources instead of failing early)
2020-04-23 19:23:41 -04:00
..