The validate rules of "min-elements" is not consistent with the RFC6020

I am using yangtools boron-sr4. I think the validate rules of "min-elements" is not consistent with the RFC6020.

See https://tools.ietf.org/html/rfc6020#page-63

7.7.3. The min-elements Statement

If "min-elements" exists in the leaf-list or list, and the leaf-list's or list's closest ancestor node is neither a non-presence container nor a case node. The "min-elements" constraint is enforced if the ancestor node exists.

But in fact the yang-data-impl's rule is like this:

if (constraints.isMandatory() || (minElements != null && minElements > 0)) {
final YangInstanceIdentifier childId = id.node(NodeIdentifier.create(child.getQName()));
LOG.debug("Adding mandatory child {}", childId);
builder.add(childId.toOptimized());
} }
}
It means that if "min-elements" is exist, the list or leaf-list node must exist.

Consider a yang module like this:
list layer-protocol {
container eth-cep-pac {
list vlan-spec

{ key 'vlan-id'; uses TypeDefinition:zte-vlan-spec; min-elements 1; }

leaf mac-adress-learning-range

{ type uint64; }
}
container eth-nep-pac {
leaf total-potential-eth-capacity { type uint64; }

leaf available-eth-capacity

{ type uint64; }

}
}
If I put "layer-protocol" without "eth-cep-pac" into configuration datastore， IllegalArgumentException occurred " missing mandatory descendant /eth-cep-pac/vlan-spec"