/**
 * Real-world example: Facebook Product Integration
 */
class FacebookProductIntegration
{
    private $facebookApi;
    private $configHelper;
    private $logger;
    
    public function aroundSave(
        \Magento\Catalog\Model\Product $subject,
        callable $proceed
    ) {
        // Check if Facebook integration is enabled
        if (!$this->configHelper->isEnabled()) {
            return $proceed();
        }
        
        // Capture original data for comparison
        $originalData = $subject->getOrigData();
        $isNew = !$subject->getId();
        
        // Validate Facebook requirements
        if (!$this->validateFacebookData($subject)) {
            $this->logger->warning(
                'Product missing Facebook requirements',
                ['sku' => $subject->getSku()]
            );
        }
        
        // Execute original save
        $result = $proceed();
        
        // Sync to Facebook if save was successful
        if ($result) {
            try {
                if ($isNew) {
                    $this->facebookApi->createProduct($subject);
                } else {
                    $this->facebookApi->updateProduct($subject, $originalData);
                }
            } catch (\Exception $e) {
                // Don't break Magento save if FB fails
                $this->logger->error($e->getMessage());
            }
        }
        
        return $result;
    }
}

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    
    <!-- Plugin Configuration -->
    <type name="Magento\Catalog\Model\Product">
        <plugin name="vendor_facebook_product_integration"
                type="Vendor\Facebook\Plugin\FacebookProductIntegration"
                sortOrder="100"
                disabled="false"/>
    </type>
    
    <!-- Plugin Dependencies -->
    <type name="Vendor\Facebook\Plugin\FacebookProductIntegration">
        <arguments>
            <argument name="facebookApi" xsi:type="object">
                Vendor\Facebook\Api\Client
            </argument>
            <argument name="configHelper" xsi:type="object">
                Vendor\Facebook\Helper\Config
            </argument>
        </arguments>
    </type>
</config>

class FacebookProductIntegrationTest extends \PHPUnit\Framework\TestCase
{
    public function testAroundSaveWhenDisabled()
    {
        // Setup mocks
        $configHelper = $this->createMock(Config::class);
        $configHelper->method('isEnabled')->willReturn(false);
        
        $plugin = new FacebookProductIntegration($configHelper);
        
        // Test that proceed is called directly
        $proceed = function() { return true; };
        $result = $plugin->aroundSave($product, $proceed);
        
        $this->assertTrue($result);
        // Verify Facebook API was not called
    }
    
    public function testAroundSaveWithFacebookError()
    {
        // Test that Magento save succeeds even if FB fails
        $facebookApi = $this->createMock(Client::class);
        $facebookApi->method('createProduct')
            ->willThrowException(new \Exception('FB Error'));
        
        // Assert save still returns true
        $this->assertTrue($result);
    }
}