Adrien Grand e9669b3762 Better validation of copy_to. (#25983)
We are currently quite lenient about the targets of `copy_to`. However in a
number of cases we can detect illegal use of `copy_to` at mapping update time.
For instance, it does not make sense to use object fields as targets of
`copy_to`, or fields that would end up in a different nested document.
2017-08-01 16:23:28 +02:00
..