Fix dob date validation on custom locale

Author: joachimVT

app/code/Magento/Customer/Block/Widget/Dob.php

@@ -208,8 +208,16 @@ public function getHtmlId()
      */
     public function getHtmlExtraParams()
     {
+        $validators = [];
+        $validators['required'] = true;
+        $validators['validate-date'] = [
+            'dateFormat' => $this->getDateFormat()
+        ];
+
+        return 'data-validate="' . $this->_escaper->escapeHtml(json_encode($validators)) . '"';
+
         $extraParams = [
-            "'validate-date-au':true"
+            "'validate-date':true",
         ];
 
         if ($this->isRequired()) {

lib/web/mage/validation.js

@@ -9,14 +9,15 @@
     if (typeof define === 'function' && define.amd) {
         define([
             'jquery',
+            'moment',
             'jquery/ui',
             'jquery/validate',
             'mage/translate'
         ], factory);
     } else {
         factory(jQuery);
     }
-}(function ($) {
+}(function ($, moment) {
     'use strict';
 
     var creditCartTypes, rules, showLabel, originValidateDelegate;
@@ -966,13 +967,12 @@
             $.mage.__('Please use only letters (a-z or A-Z) or numbers (0-9) in this field. No spaces or other characters are allowed.') //eslint-disable-line max-len
         ],
         'validate-date': [
-            function (v) {
-                var test = new Date(v);
+            function (value, params, additionalParams) {
+                var test = moment(value, additionalParams.dateFormat);
 
-                return $.mage.isEmptyNoTrim(v) || !isNaN(test);
+                return $.mage.isEmptyNoTrim(value) || test.isValid();
             },
             $.mage.__('Please enter a valid date.')
-
         ],
         'validate-date-range': [
             function (v, elm) {