set created at if field list is passed to save method

lib/dao.js

@@ -85,9 +85,21 @@ module.exports = (function() {
   // only those fields will be updated
   DAO.prototype.save = function(fields) {
     var self          = this
-      , values = fields ? {} : this.values;
+      , values        = fields ? {} : this.values
+      , updatedAtAttr = this.__options.underscored ? 'updated_at' : 'updatedAt'
+      , createdAtAttr = this.__options.underscored ? 'created_at' : 'createdAt'
 
     if(fields) {
+      if(self.__options.timestamps) {
+        if(fields.indexOf(updatedAtAttr) === -1) {
+          fields.push(updatedAtAttr)
+        }
+
+        if(fields.indexOf(createdAtAttr) === -1) {
+          fields.push(createdAtAttr)
+        }
+      }
+
       fields.forEach(function(field) {
         if(self.values[field]) {
           values[field] = self.values[field]
@@ -95,7 +107,6 @@ module.exports = (function() {
       });
     }
 
-    var updatedAtAttr = this.__options.underscored ? 'updated_at' : 'updatedAt'
 
     if(this.__options.timestamps && this.hasOwnProperty(updatedAtAttr)) {
       var now = new Date()
@@ -189,6 +200,7 @@ module.exports = (function() {
     var self = this
 
     var readOnlyAttributes = Utils._.keys(this.__factory.primaryKeys)
+
     readOnlyAttributes.push('id')
     readOnlyAttributes.push('createdAt')
     readOnlyAttributes.push('updatedAt')
@@ -264,9 +276,10 @@ module.exports = (function() {
       defaults[this.__options.underscored ? 'created_at' : 'createdAt'] = new Date()
       defaults[this.__options.underscored ? 'updated_at' : 'updatedAt'] = new Date()
 
-      if(this.__options.paranoid)
+      if(this.__options.paranoid) {
         defaults[this.__options.underscored ? 'deleted_at' : 'deletedAt'] = null
       }
+    }
 
     Utils._.map(defaults, function(value, attr) {
       if(!self.hasOwnProperty(attr)) {