class DeprecatedClassHelper

class DeprecatedClassHelper {
    
    /** @var ReflectionProvider */
    private $reflectionProvider;
    public function __construct(ReflectionProvider $reflectionProvider) {
        $this->reflectionProvider = $reflectionProvider;
    }
    public function getClassDeprecationDescription(ClassReflection $class) : string {
        $description = $class->getDeprecatedDescription();
        if ($description === null) {
            return '.';
        }
        return sprintf(":\n%s", $description);
    }
    
    /**
     * @param string[] $referencedClasses
     * @return ClassReflection[]
     */
    public function filterDeprecatedClasses(array $referencedClasses) : array {
        $deprecatedClasses = [];
        foreach ($referencedClasses as $referencedClass) {
            try {
                $class = $this->reflectionProvider
                    ->getClass($referencedClass);
            } catch (ClassNotFoundException $e) {
                continue;
            }
            if (!$class->isDeprecated()) {
                continue;
            }
            $deprecatedClasses[] = $class;
        }
        return $deprecatedClasses;
    }

}