Hardy Ferentschik while it's not supported per se, ValidatorImpl#collectMetaConstraintsForPath is supposed to work (at least there is logic to deal with it) but the logic is wrong: it supposes that getIndex() will return the index if we are in the isIterable() case while it will return null as getIndex() returns the index of the parent.

getIndex() should be called on the child of the isIterable() node, not on the node itself.

I prepared a PR to fix this issue.