8003: Using System Value for Base Currency Results in Config Error.

Author: nmalevanec

app/code/Magento/Directory/Model/Currency.php

@@ -67,7 +67,7 @@ class Currency extends \Magento\Framework\Model\AbstractModel
     protected $_localeCurrency;
 
     /**
-     * @var CurrencySystemConfig
+     * @var CurrencyConfig
      */
     private $currencyConfig;
 
@@ -82,7 +82,7 @@ class Currency extends \Magento\Framework\Model\AbstractModel
      * @param \Magento\Framework\Model\ResourceModel\AbstractResource $resource
      * @param \Magento\Framework\Data\Collection\AbstractDb $resourceCollection
      * @param array $data
-     * @param CurrencySystemConfig|null $currencyConfig
+     * @param CurrencyConfig|null $currencyConfig
      * @SuppressWarnings(PHPMD.ExcessiveParameterList)
      */
     public function __construct(
@@ -96,7 +96,7 @@ public function __construct(
         \Magento\Framework\Model\ResourceModel\AbstractResource $resource = null,
         \Magento\Framework\Data\Collection\AbstractDb $resourceCollection = null,
         array $data = [],
-        CurrencySystemConfig $currencyConfig = null
+        CurrencyConfig $currencyConfig = null
     ) {
         parent::__construct(
             $context,
@@ -110,7 +110,7 @@ public function __construct(
         $this->_directoryHelper = $directoryHelper;
         $this->_currencyFilterFactory = $currencyFilterFactory;
         $this->_localeCurrency = $localeCurrency;
-        $this->currencyConfig = $currencyConfig ?: ObjectManager::getInstance()->get(CurrencySystemConfig::class);
+        $this->currencyConfig = $currencyConfig ?: ObjectManager::getInstance()->get(CurrencyConfig::class);
     }
 
     /**
@@ -356,8 +356,7 @@ public function getOutputFormat()
      */
     public function getConfigAllowCurrencies()
     {
-        $allowedCurrencies = $this->_getResource()->getConfigCurrencies($this, self::XML_PATH_CURRENCY_ALLOW) ?:
-            $this->currencyConfig->getConfigCurrencies(self::XML_PATH_CURRENCY_ALLOW);
+        $allowedCurrencies = $this->currencyConfig->getConfigCurrencies(self::XML_PATH_CURRENCY_ALLOW);
         $appBaseCurrencyCode = $this->_directoryHelper->getBaseCurrencyCode();
         if (!in_array($appBaseCurrencyCode, $allowedCurrencies)) {
             $allowedCurrencies[] = $appBaseCurrencyCode;
@@ -379,20 +378,15 @@ public function getConfigAllowCurrencies()
      */
     public function getConfigDefaultCurrencies()
     {
-        $defaultCurrencies = $this->_getResource()->getConfigCurrencies($this, self::XML_PATH_CURRENCY_DEFAULT) ?:
-            $this->currencyConfig->getConfigCurrencies(self::XML_PATH_CURRENCY_DEFAULT);
-
-        return $defaultCurrencies;
+        return $this->currencyConfig->getConfigCurrencies(self::XML_PATH_CURRENCY_DEFAULT);
     }
 
     /**
      * @return array
      */
     public function getConfigBaseCurrencies()
     {
-        $defaultCurrencies = $this->_getResource()->getConfigCurrencies($this, self::XML_PATH_CURRENCY_BASE) ?:
-            $this->currencyConfig->getConfigCurrencies(self::XML_PATH_CURRENCY_BASE);
-        return $defaultCurrencies;
+        return $this->currencyConfig->getConfigCurrencies(self::XML_PATH_CURRENCY_BASE);
     }
 
     /**

app/code/Magento/Directory/Model/CurrencyConfig.php

@@ -0,0 +1,99 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+namespace Magento\Directory\Model;
+
+use Magento\Framework\App\Area;
+use Magento\Framework\App\Config\ScopeConfigInterface;
+use Magento\Framework\App\State;
+use Magento\Store\Model\ScopeInterface;
+use Magento\Store\Model\StoreManagerInterface;
+
+/**
+ * Provide config values for allowed, base and default currencies.
+ */
+class CurrencyConfig
+{
+    /**
+     * @var State
+     */
+    private $appState;
+
+    /**
+     * @var ScopeConfigInterface
+     */
+    private $config;
+
+    /**
+     * @var StoreManagerInterface
+     */
+    private $storeManager;
+
+    /**
+     * CurrencyConfig constructor.
+     *
+     * @param State $appState
+     * @param ScopeConfigInterface $config
+     * @param StoreManagerInterface $storeManager
+     */
+    public function __construct(
+        State $appState,
+        ScopeConfigInterface $config,
+        StoreManagerInterface $storeManager
+    ) {
+        $this->appState = $appState;
+        $this->config = $config;
+        $this->storeManager = $storeManager;
+    }
+
+    /**
+     * Retrieve config currency data by config path.
+     *
+     * @param string $path
+     * @return array
+     */
+    public function getConfigCurrencies(string $path)
+    {
+        $result = $this->appState->getAreaCode() === Area::AREA_ADMINHTML
+            ? $this->getConfigForAllStores($path)
+            : $this->getConfigForCurrentStore($path);
+        sort($result);
+
+        return array_unique($result);
+    }
+
+    /**
+     * Get allowed, base and default currency codes for all stores.
+     *
+     * @param string $path
+     * @return array
+     */
+    private function getConfigForAllStores(string $path)
+    {
+        $storesResult = [[]];
+        foreach ($this->storeManager->getStores() as $store) {
+            $storesResult[] = explode(
+                ',',
+                $this->config->getValue($path, ScopeInterface::SCOPE_STORE, $store->getCode())
+            );
+        }
+
+        return array_merge(...$storesResult);
+    }
+
+    /**
+     * Get allowed, base and default currency codes for current store.
+     *
+     * @param string $path
+     * @return mixed
+     */
+    private function getConfigForCurrentStore(string $path)
+    {
+        $store = $this->storeManager->getStore();
+
+        return explode(',', $this->config->getValue($path, ScopeInterface::SCOPE_STORE, $store->getCode()));
+    }
+}

app/code/Magento/Directory/Model/CurrencySystemConfig.php

@@ -165,6 +165,8 @@ public function saveRates($rates)
      * @param string $path
      * @return array
      * @SuppressWarnings(PHPMD.UnusedFormalParameter)
+     * @deprecated because doesn't take into consideration scopes and system config values.
+     * @see \Magento\Directory\Model\CurrencyConfig::getConfigCurrencies()
      */
     public function getConfigCurrencies($model, $path)
     {