refactor: make saveSubdocsPreSave async

Author: vkarpov15

lib/plugins/saveSubdocs.js

@@ -1,41 +1,36 @@
 'use strict';
 
-const each = require('../helpers/each');
-
 /*!
  * ignore
  */
 
 module.exports = function saveSubdocs(schema) {
   const unshift = true;
-  schema.s.hooks.pre('save', false, function saveSubdocsPreSave(next) {
+  schema.s.hooks.pre('save', false, async function saveSubdocsPreSave() {
     if (this.$isSubdocument) {
-      next();
       return;
     }
 
     const _this = this;
     const subdocs = this.$getAllSubdocs({ useCache: true });
 
     if (!subdocs.length) {
-      next();
       return;
     }
 
-    each(subdocs, function(subdoc, cb) {
-      subdoc.$__schema.s.hooks.execPre('save', subdoc, function(err) {
-        cb(err);
+    await Promise.all(subdocs.map(async (subdoc) => {
+      return new Promise((resolve, reject) => {
+        subdoc.$__schema.s.hooks.execPre('save', subdoc, function(err) {
+          if (err) reject(err);
+          else resolve();
+        });
       });
-    }, function(error) {
-      // Invalidate subdocs cache because subdoc pre hooks can add new subdocuments
-      if (_this.$__.saveOptions) {
-        _this.$__.saveOptions.__subdocs = null;
-      }
-      if (error) {
-        return next(error);
-      }
-      next();
-    });
+    }));
+
+    // Invalidate subdocs cache because subdoc pre hooks can add new subdocuments
+    if (_this.$__.saveOptions) {
+      _this.$__.saveOptions.__subdocs = null;
+    }
   }, null, unshift);
 
   schema.s.hooks.post('save', async function saveSubdocsPostDeleteOne() {