Actually merge properties.

config/model/anything.yml

@@ -5,15 +5,14 @@ abstract: true
 
 properties:
   "pas:id":
-    label: DRS ID
+    label: Primary ID
     type: string
     min_cardinality: 1
     max_cardinality: 1
 
   "pas:refId":
-    label: DRS ID
+    label: External system ID
     type: string
-    max_cardinality: 1
 
   "pas:prefLabel":
     label: Preferred Label

model_parser.lua

@@ -55,7 +55,9 @@ M.parse_model = function(mod_id)
         for k, v in pairs(src) do
             if NO_INHERIT[k] then goto continue end
             if type(v) == "table" then
-                merge(v, dest[k] or {})
+                dest[k] = dest[k] or {}
+                assert(type(dest[k]) == "table")
+                merge(v, dest[k])
             else
                 dest[k] = v
             end
@@ -65,7 +67,6 @@ M.parse_model = function(mod_id)
     local config = {}
 
     for _, src_config in ipairs(hierarchy) do
-        print("Merging:", src_config)
         merge(src_config, config)
     end