Refactoring day1

node_modules/mongoose/lib/helpers/document/compile.js

@@ -124,13 +124,6 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
             }
           });
 
-          Object.defineProperty(nested, '$__parent', {
-            enumerable: false,
-            configurable: true,
-            writable: false,
-            value: this
-          });
-
           compile(subprops, nested, path, options);
           this.$__.getters[path] = nested;
         }
@@ -138,10 +131,8 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
         return this.$__.getters[path];
       },
       set: function(v) {
-        if (v != null && v.$__isNested) {
-          // Convert top-level to POJO, but leave subdocs hydrated so `$set`
-          // can handle them. See gh-9293.
-          v = v.$__parent.get(path);
+        if (v instanceof Document) {
+          v = v.toObject({ transform: false });
         }
         const doc = this.$__[scopeSymbol] || this;
         doc.$set(path, v);