fix(document): support getter setting virtual on manually populated d…

…oc when calling toJSON()

Fix #8295

lib/document.js

@@ -2836,6 +2836,13 @@ Document.prototype.$toObject = function(options, json) {
     minimize: _minimize
   });
 
+  if (utils.hasUserDefinedProperty(options, 'getters')) {
+    cloneOptions.getters = options.getters;
+  }
+  if (utils.hasUserDefinedProperty(options, 'virtuals')) {
+    cloneOptions.virtuals = options.virtuals;
+  }
+
   const depopulate = options.depopulate ||
     get(options, '_parentOptions.depopulate', false);
   // _isNested will only be true if this is not the top level document, we
@@ -2852,6 +2859,10 @@ Document.prototype.$toObject = function(options, json) {
   options.minimize = _minimize;
 
   cloneOptions._parentOptions = options;
+  cloneOptions._skipSingleNestedGetters = true;
+
+  const gettersOptions = Object.assign({}, cloneOptions);
+  gettersOptions._skipSingleNestedGetters = false;
 
   // remember the root transform function
   // to save it from being overwritten by sub-transform functions
@@ -2860,16 +2871,15 @@ Document.prototype.$toObject = function(options, json) {
   let ret = clone(this._doc, cloneOptions) || {};
 
   if (options.getters) {
-    applyGetters(this, ret, cloneOptions);
-    // applyGetters for paths will add nested empty objects;
-    // if minimize is set, we need to remove them.
+    applyGetters(this, ret, gettersOptions);
+
     if (options.minimize) {
       ret = minimize(ret) || {};
     }
   }
 
-  if (options.virtuals || options.getters && options.virtuals !== false) {
-    applyVirtuals(this, ret, cloneOptions, options);
+  if (options.virtuals || (options.getters && options.virtuals !== false)) {
+    applyVirtuals(this, ret, gettersOptions, options);
   }
 
   if (options.versionKey === false && this.schema.options.versionKey) {
@@ -3180,12 +3190,7 @@ function applyGetters(self, json, options) {
       v = cur[part];
       if (ii === last) {
         const val = self.get(path);
-        // Ignore single nested docs: getters will run because of `clone()`
-        // before `applyGetters()` in `$toObject()`. Quirk because single
-        // nested subdocs are hydrated docs in `_doc` as opposed to POJOs.
-        if (val != null && val.$__ == null) {
-          branch[part] = clone(val, options);
-        }
+        branch[part] = clone(val, options);
       } else if (v == null) {
         if (part in cur) {
           branch[part] = v;

lib/utils.js

@@ -193,6 +193,11 @@ exports.clone = function clone(obj, options, isArrayChild) {
   }
 
   if (isMongooseObject(obj)) {
+    // Single nested subdocs should apply getters later in `applyGetters()`
+    // when calling `toObject()`. See gh-7442, gh-8295
+    if (options && options._skipSingleNestedGetters && obj.$isSingleNested) {
+      options = Object.assign({}, options, { getters: false });
+    }
     if (options && options.json && typeof obj.toJSON === 'function') {
       return obj.toJSON(options);
     }