Magento 2 Code Generation – “Incorrect dependency in class”

When running a php bin/magento setup:di:compile you may have at some point run into the “Incorrect dependency in class” errors during the generation of the code. They look a little something like this:

This happens when you include a class in your constructor that is already available inside $context. The solution to this problem is actually quite simple. Instead of doing something like this

public function __construct(
    Context $context,
    \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig,
) {
    parent::__construct($context);
    $this->config = $scopeConfig;
}

You should do the following as the ScopeConfigInterface is available from $context

public function __construct(
    Context $context,
) {
    parent::__construct($context);
    $this->config = $context->getScopeConfig();
}

This will solve the above generation error and also make the code look a little neater, helping to keep the code clean and maintainable.

There are other classes available in the $context to.

Block Context

$context->getRequest();           // \Magento\Framework\App\RequestInterface
$context->getUrlBuilder();        // \Magento\Framework\UrlInterface
$context->getScopeConfig();       // \Magento\Framework\App\Config\ScopeConfigInterface
$context->getLogger();            // \Psr\Log\LoggerInterface
$context->getEventManager();      // \Magento\Framework\Event\ManagerInterface
$context->getStoreManager();      // \Magento\Store\Model\StoreManagerInterface
$context->getPageConfig();        // \Magento\Framework\View\Page\Config
$context->getFilesystem();        // \Magento\Framework\Filesystem
$context->getViewFileSystem();    // \Magento\Framework\View\FileSystem
$context->getAppState();          // \Magento\Framework\App\State
$context->getCache();             // \Magento\Framework\App\CacheInterface
$context->getSession();           // \Magento\Framework\Session\SessionManagerInterface
$context->getInlineTranslation(); // \Magento\Framework\Translate\Inline\StateInterface
$context->getEscaper();           // \Magento\Framework\Escaper
$context->getLocaleDate();        // \Magento\Framework\Stdlib\DateTime\TimezoneInterface
$context->getDesignPackage();     // \Magento\Framework\View\DesignInterface
$context->getLayout();            // \Magento\Framework\View\LayoutInterface
$context->getSidResolver();       // \Magento\Framework\Session\SidResolverInterface
$context->getAssetRepository();   // \Magento\Framework\View\Asset\Repository
$context->getViewConfig();        // \Magento\Framework\View\ConfigInterface
$context->getCacheState();        // \Magento\Framework\App\Cache\StateInterface
$context->getFilterManager();     // \Magento\Framework\Filter\FilterManager

Helper Context

$context->getRequest();       // \Magento\Framework\App\RequestInterface
$context->getUrlBuilder();    // \Magento\Framework\UrlInterface
$context->getScopeConfig();   // \Magento\Framework\App\Config\ScopeConfigInterface
$context->getLogger();        // \Psr\Log\LoggerInterface
$context->getEventManager();  // \Magento\Framework\Event\ManagerInterface
$context->getModuleManager(); // \Magento\Framework\Module\Manager
$context->getCacheConfig();   // \Magento\Framework\Cache\ConfigInterface
$context->getHttpHeader();    // \Magento\Framework\HTTP\Header
$context->getRemoteAddress(); // \Magento\Framework\HTTP\PhpEnvironment\RemoteAddress
$context->getUrlEncoder();    // \Magento\Framework\Url\EncoderInterface
$context->getUrlDecoder();    // \Magento\Framework\Url\DecoderInterface

Model Context

$context->getLogger();          // \Psr\Log\LoggerInterface
$context->getCacheManager();    // \Magento\Framework\App\CacheInterface
$context->getEventDispatcher(); // \Magento\Framework\Event\ManagerInterface
$context->getAppState();        // \Magento\Framework\App\State
$context->getLogger();          // \Psr\Log\LoggerInterface