ENGCOM-3460: [Newsletter] Fixing the customer subscribing from different stores #19195

 - Merge Pull Request magento/magento2#19195 from eduard13/magento2:2.3-develop-19172-issue
 - Merged commits:
   1. c9b5250
   2. 3b84172

Author: magento-engcom-team

app/code/Magento/Newsletter/Model/Plugin/CustomerPlugin.php

@@ -6,11 +6,13 @@
 namespace Magento\Newsletter\Model\Plugin;
 
 use Magento\Customer\Api\CustomerRepositoryInterface as CustomerRepository;
+use Magento\Customer\Api\Data\CustomerExtensionInterface;
 use Magento\Customer\Api\Data\CustomerInterface;
-use Magento\Newsletter\Model\SubscriberFactory;
 use Magento\Framework\Api\ExtensionAttributesFactory;
+use Magento\Framework\App\ObjectManager;
 use Magento\Newsletter\Model\ResourceModel\Subscriber;
-use Magento\Customer\Api\Data\CustomerExtensionInterface;
+use Magento\Newsletter\Model\SubscriberFactory;
+use Magento\Store\Model\StoreManagerInterface;
 
 class CustomerPlugin
 {
@@ -36,21 +38,29 @@ class CustomerPlugin
      */
     private $customerSubscriptionStatus = [];
 
+    /**
+     * @var StoreManagerInterface
+     */
+    private $storeManager;
+
     /**
      * Initialize dependencies.
      *
      * @param SubscriberFactory $subscriberFactory
      * @param ExtensionAttributesFactory $extensionFactory
      * @param Subscriber $subscriberResource
+     * @param StoreManagerInterface|null $storeManager
      */
     public function __construct(
         SubscriberFactory $subscriberFactory,
         ExtensionAttributesFactory $extensionFactory,
-        Subscriber $subscriberResource
+        Subscriber $subscriberResource,
+        StoreManagerInterface $storeManager = null
     ) {
         $this->subscriberFactory = $subscriberFactory;
         $this->extensionFactory = $extensionFactory;
         $this->subscriberResource = $subscriberResource;
+        $this->storeManager = $storeManager ?: ObjectManager::getInstance()->get(StoreManagerInterface::class);
     }
 
     /**
@@ -151,7 +161,8 @@ public function afterDelete(CustomerRepository $subject, $result, CustomerInterf
     public function afterGetById(CustomerRepository $subject, CustomerInterface $customer)
     {
         $extensionAttributes = $customer->getExtensionAttributes();
-
+        $storeId = $this->storeManager->getStore()->getId();
+        $customer->setStoreId($storeId);
         if ($extensionAttributes === null) {
             /** @var CustomerExtensionInterface $extensionAttributes */
             $extensionAttributes = $this->extensionFactory->create(CustomerInterface::class);

app/code/Magento/Newsletter/Test/Unit/Model/Plugin/CustomerPluginTest.php

@@ -10,6 +10,8 @@
 use Magento\Customer\Api\Data\CustomerExtensionInterface;
 use Magento\Framework\Api\ExtensionAttributesFactory;
 use Magento\Newsletter\Model\ResourceModel\Subscriber;
+use Magento\Store\Model\Store;
+use Magento\Store\Model\StoreManagerInterface;
 
 class CustomerPluginTest extends \PHPUnit\Framework\TestCase
 {
@@ -53,6 +55,11 @@ class CustomerPluginTest extends \PHPUnit\Framework\TestCase
      */
     private $customerMock;
 
+    /**
+     * @var StoreManagerInterface|\PHPUnit_Framework_MockObject_MockObject
+     */
+    private $storeManagerMock;
+
     protected function setUp()
     {
         $this->subscriberFactory = $this->getMockBuilder(\Magento\Newsletter\Model\SubscriberFactory::class)
@@ -87,6 +94,8 @@ protected function setUp()
             ->setMethods(['getExtensionAttributes'])
             ->disableOriginalConstructor()
             ->getMockForAbstractClass();
+        $this->storeManagerMock = $this->createMock(StoreManagerInterface::class);
+
         $this->subscriberFactory->expects($this->any())->method('create')->willReturn($this->subscriber);
         $this->objectManager = new \Magento\Framework\TestFramework\Unit\Helper\ObjectManager($this);
 
@@ -96,6 +105,7 @@ protected function setUp()
                 'subscriberFactory' => $this->subscriberFactory,
                 'extensionFactory' => $this->extensionFactoryMock,
                 'subscriberResource' => $this->subscriberResourceMock,
+                'storeManager' => $this->storeManagerMock,
             ]
         );
     }
@@ -206,6 +216,7 @@ public function testAfterGetByIdCreatesExtensionAttributesIfItIsNotSet(
     ) {
         $subject = $this->createMock(\Magento\Customer\Api\CustomerRepositoryInterface::class);
         $subscriber = [$subscriberStatusKey => $subscriberStatusValue];
+        $this->prepareStoreData();
 
         $this->extensionFactoryMock->expects($this->any())
             ->method('create')
@@ -233,6 +244,7 @@ public function testAfterGetByIdSetsIsSubscribedFlagIfItIsNotSet()
     {
         $subject = $this->createMock(\Magento\Customer\Api\CustomerRepositoryInterface::class);
         $subscriber = ['subscriber_id' => 1, 'subscriber_status' => 1];
+        $this->prepareStoreData();
 
         $this->customerMock->expects($this->any())
             ->method('getExtensionAttributes')
@@ -267,4 +279,17 @@ public function afterGetByIdDataProvider()
             [null, null, false],
         ];
     }
+
+    /**
+     * Prepare store information
+     *
+     * @return void
+     */
+    private function prepareStoreData()
+    {
+        $storeId = 1;
+        $storeMock = $this->createMock(Store::class);
+        $storeMock->expects($this->any())->method('getId')->willReturn($storeId);
+        $this->storeManagerMock->expects($this->any())->method('getStore')->willReturn($storeMock);
+    }
 }