This is my YANG doctors review of the ietf-factory-default.yang module as
part of draft-ietf-netmod-factory-default-07.

The module cleanly passes validation using the YANG validator site and
I have successfully loaded it into one NETCONF server implementation.

This module is ready with a cosmetic nit and a suggestion.

I suggest fixing the following textual nit:

OLD
       configuration datastores (i.e.,<running> , <startup><candidate>) to
       their factory default content.";

NEW:
       configuration datastores (i.e. <running>, <startup>, and
       <candidate>) to their factory default content.";

I suggest adding a revision-date to the filename in the <CODE BEGINS> block.

OLD:
 <CODE BEGINS> file "ietf-factory-default.yang"

 NEW:
 <CODE BEGINS> file "ietf-factory-default@2019-11-27.yang"

 (Obviously replacing the date with the release date of the module)