we're hitting a null module reference in an openconfig model (openconfig-interfaces).

I'm seeing this in Carbon-SR1 and in Master.

the device YANG model (openconfig-interfaces) has a deviation in IOS XR that impacts a leaf with a relative leafref in. The error we hit seems to be caused by a relative leafref.

the deviation is:

deviation /ocif:interfaces/ocif:interface/ocif:subinterfaces/ocif:subinterface/ocif:config/ocif:unnumbered

{ deviate not-supported; }

that corresponds to this in the openconfig model:

leaf unnumbered {
type leafref

{ path "../../index"; }

description
"Indicates that the subinterface is unnumbered, and provides
a reference to the subinterface that provides the IP
address information (v4, v6 or both) for the current
subinterface.";
}

logs (from master - enhanced with extra debugs) attached.

I added these lines in the relative leafref case in method getBaseTypeForLeafRef in SchemaContextUtil.java:

LOG.debug("parent module {}", parentModule);
LOG.debug("schema context {}", schemaContext);
LOG.debug("schema {}", schema);

these lines are getting triggered and show a null parent module (resulting from the previous line):

Module parentModule = findParentModule(schemaContext, schema);