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

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

@@ -6,6 +6,7 @@
 
 namespace Magento\Directory\Model;
 
+use Magento\Framework\App\ObjectManager;
 use Magento\Framework\Exception\InputException;
 use Magento\Directory\Model\Currency\Filter;
 
@@ -65,6 +66,11 @@ class Currency extends \Magento\Framework\Model\AbstractModel
      */
     protected $_localeCurrency;
 
+    /**
+     * @var CurrencyConfig
+     */
+    private $currencyConfig;
+
     /**
      * @param \Magento\Framework\Model\Context $context
      * @param \Magento\Framework\Registry $registry
@@ -76,6 +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 CurrencyConfig $currencyConfig
      * @SuppressWarnings(PHPMD.ExcessiveParameterList)
      */
     public function __construct(
@@ -88,7 +95,8 @@ public function __construct(
         \Magento\Framework\Locale\CurrencyInterface $localeCurrency,
         \Magento\Framework\Model\ResourceModel\AbstractResource $resource = null,
         \Magento\Framework\Data\Collection\AbstractDb $resourceCollection = null,
-        array $data = []
+        array $data = [],
+        CurrencyConfig $currencyConfig = null
     ) {
         parent::__construct(
             $context,
@@ -102,6 +110,7 @@ public function __construct(
         $this->_directoryHelper = $directoryHelper;
         $this->_currencyFilterFactory = $currencyFilterFactory;
         $this->_localeCurrency = $localeCurrency;
+        $this->currencyConfig = $currencyConfig ?: ObjectManager::getInstance()->get(CurrencyConfig::class);
     }
 
     /**
@@ -347,7 +356,7 @@ public function getOutputFormat()
      */
     public function getConfigAllowCurrencies()
     {
-        $allowedCurrencies = $this->_getResource()->getConfigCurrencies($this, 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;
@@ -369,17 +378,15 @@ public function getConfigAllowCurrencies()
      */
     public function getConfigDefaultCurrencies()
     {
-        $defaultCurrencies = $this->_getResource()->getConfigCurrencies($this, 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);
-        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/ResourceModel/Currency.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)
     {

app/code/Magento/Directory/Test/Unit/Model/CurrencyConfigTest.php

@@ -0,0 +1,127 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+namespace Magento\Directory\Test\Unit\Model;
+
+use Magento\Config\App\Config\Type\System;
+use Magento\Directory\Model\CurrencyConfig;
+use Magento\Framework\App\Area;
+use Magento\Framework\App\Config\ScopeConfigInterface;
+use Magento\Framework\App\State;
+use Magento\Framework\TestFramework\Unit\Helper\ObjectManager;
+use Magento\Store\Api\Data\StoreInterface;
+use Magento\Store\Model\StoreManagerInterface;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Provide tests for CurrencyConfig model.
+ */
+class CurrencyConfigTest extends TestCase
+{
+    /**
+     * @var CurrencyConfig
+     */
+    private $testSubject;
+
+    /**
+     * @var System|\PHPUnit_Framework_MockObject_MockObject
+     */
+    private $config;
+
+    /**
+     * @var StoreManagerInterface|\PHPUnit_Framework_MockObject_MockObject
+     */
+    private $storeManager;
+
+    /**
+     * @var State|\PHPUnit_Framework_MockObject_MockObject
+     */
+    private $appState;
+
+    /**
+     * @inheritdoc
+     */
+    protected function setUp()
+    {
+        $this->config = $this->getMockBuilder(ScopeConfigInterface::class)
+            ->disableOriginalConstructor()
+            ->getMock();
+        $this->storeManager = $this->getMockBuilder(StoreManagerInterface::class)
+            ->setMethods(['getStores', 'getWebsites'])
+            ->disableOriginalConstructor()
+            ->getMockForAbstractClass();
+        $this->appState = $this->getMockBuilder(State::class)
+            ->disableOriginalConstructor()
+            ->getMock();
+        $objectManager = new ObjectManager($this);
+        $this->testSubject = $objectManager->getObject(
+            CurrencyConfig::class,
+            [
+                'storeManager' => $this->storeManager,
+                'appState' => $this->appState,
+                'config' => $this->config,
+            ]
+        );
+    }
+
+    /**
+     * Test get currency config for admin and storefront areas.
+     *
+     * @dataProvider getConfigCurrenciesDataProvider
+     * @return void
+     */
+    public function testGetConfigCurrencies(string $areCode)
+    {
+        $path = 'test/path';
+        $expected = ['ARS', 'AUD', 'BZD'];
+
+        $this->appState->expects(self::once())
+            ->method('getAreaCode')
+            ->willReturn($areCode);
+
+        /** @var StoreInterface|\PHPUnit_Framework_MockObject_MockObject $store */
+        $store = $this->getMockBuilder(StoreInterface::class)
+            ->setMethods(['getCode'])
+            ->disableOriginalConstructor()
+            ->getMockForAbstractClass();
+        $store->expects(self::once())
+            ->method('getCode')
+            ->willReturn('testCode');
+
+        if ($areCode === Area::AREA_ADMINHTML) {
+            $this->storeManager->expects(self::once())
+                ->method('getStores')
+                ->willReturn([$store]);
+        } else {
+            $this->storeManager->expects(self::once())
+                ->method('getStore')
+                ->willReturn($store);
+        }
+
+        $this->config->expects(self::once())
+            ->method('getValue')
+            ->with(
+                self::identicalTo($path)
+            )->willReturn('ARS,AUD,BZD');
+
+        $result = $this->testSubject->getConfigCurrencies($path);
+
+        self::assertEquals($expected, $result);
+    }
+
+    /**
+     * Provide test data for getConfigCurrencies test.
+     *
+     * @return array
+     */
+    public function getConfigCurrenciesDataProvider()
+    {
+        return [
+            ['areaCode' => Area::AREA_ADMINHTML],
+            ['areaCode' => Area::AREA_FRONTEND],
+        ];
+    }
+}