is
Validates the specified group set against the items mapping.
If those are invalid, throws an exception that includes error messages.
Every MatchGroup.members coordinate must exist as a key in items.
No coordinate may belong to more than one group.
Every coordinate in items must belong to exactly one group (no gaps).
Since
5.3.0
Parameters
groups
Set of MatchGroup
items
Item mapping on ShapelessGroupRecipe