fix: proxy with BackedEnum integer on identifier

Author: Gwemox

src/Proxy/ProxyGenerator.php

@@ -27,6 +27,7 @@
 use function chmod;
 use function class_exists;
 use function dirname;
+use function enum_exists;
 use function explode;
 use function file;
 use function file_put_contents;
@@ -940,7 +941,12 @@ private function generateMethods(ClassMetadata $class)
             if ($this->isShortIdentifierGetter($method, $class)) {
                 $identifier = lcfirst(substr($name, 3));
                 $fieldType  = $class->getTypeOfField($identifier);
-                $cast       = in_array($fieldType, ['integer', 'smallint'], true) ? '(int) ' : '';
+
+                if (ClassUtils::containsEnumType($method->getReturnType())) {
+                    $cast = '';
+                } else {
+                    $cast = in_array($fieldType, ['integer', 'smallint'], true) ? '(int) ' : '';
+                }
 
                 $methods .= '        if ($this->__isInitialized__ === false) {' . "\n";
                 $methods .= '            ';

src/Util/ClassUtils.php

@@ -4,14 +4,21 @@
 
 use Doctrine\Persistence\Proxy;
 use ReflectionClass;
+use ReflectionIntersectionType;
+use ReflectionNamedType;
+use ReflectionUnionType;
 
+use function assert;
+use function enum_exists;
 use function get_class;
 use function get_parent_class;
 use function ltrim;
 use function rtrim;
 use function strrpos;
 use function substr;
 
+use const PHP_VERSION_ID;
+
 /**
  * Class and reflection related functionality for objects that
  * might or not be proxy objects at the moment.
@@ -110,4 +117,31 @@ public static function generateProxyClassName($className, $proxyNamespace)
     {
         return rtrim($proxyNamespace, '\\') . '\\' . Proxy::MARKER . '\\' . ltrim($className, '\\');
     }
+
+    /**
+     * Check if the type is an enum type or type containing an enum type
+     *
+     * @param ReflectionNamedType|ReflectionUnionType|ReflectionIntersectionType|null $type
+     *
+     */
+    public static function containsEnumType($type): bool
+    {
+        if (PHP_VERSION_ID <= 80100 || $type === null) {
+            return false;
+        }
+
+        if ($type instanceof ReflectionUnionType || $type instanceof ReflectionIntersectionType) {
+            foreach ($type->getTypes() as $unionedType) {
+                if (self::containsEnumType($unionedType)) {
+                    return true;
+                }
+            }
+
+            return false;
+        }
+
+        assert($type instanceof ReflectionNamedType);
+
+        return enum_exists($type->getName());
+    }
 }