From 88d5e18da6a82d5923012f64e090e69fd94ea0d1 Mon Sep 17 00:00:00 2001
From: Mateusz Lerczak <mlerczak@pl.sii.eu>
Date: Mon, 18 Jun 2018 22:47:46 +0200
Subject: [PATCH] Fix currency validator on BE. Throw error when value is
 empty.

---
 app/code/Magento/Config/Model/Config/Backend/Locale.php | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/app/code/Magento/Config/Model/Config/Backend/Locale.php b/app/code/Magento/Config/Model/Config/Backend/Locale.php
index 7675a0937eb44..ba3ca598aa9be 100644
--- a/app/code/Magento/Config/Model/Config/Backend/Locale.php
+++ b/app/code/Magento/Config/Model/Config/Backend/Locale.php
@@ -78,6 +78,10 @@ public function __construct(
      */
     public function afterSave()
     {
+        if (empty($this->getValue())) {
+            return parent::afterSave();
+        }
+
         /** @var $collection \Magento\Config\Model\ResourceModel\Config\Data\Collection */
         $collection = $this->_configsFactory->create();
         $collection->addPathFilter('currency/options');