Add mapped superclass case to ToManyRelationPropertyTypeResolver

rules-tests/CodeQuality/Rector/Property/TypedPropertyFromToManyRelationTypeRector/Fixture/ODM/collection_of_superclass.php.inc

@@ -0,0 +1,44 @@
+<?php
+
+namespace Rector\Doctrine\Tests\CodeQuality\Rector\Property\TypedPropertyFromToManyRelationTypeRector\Fixture\ODM;
+
+use Doctrine\Common\Collections\ArrayCollection;
+use Doctrine\Common\Collections\Collection;
+use Rector\Doctrine\Tests\CodeQuality\Rector\Property\TypedPropertyFromToManyRelationTypeRector\Source\TrainingTerm;
+
+final class CollectionOfSuperClass
+{
+    /**
+     * @\Doctrine\ODM\MongoDB\Mapping\Annotations\EmbedMany()
+     */
+    private ?Collection $trainingTerms = null;
+
+    public function __construct()
+    {
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Doctrine\Tests\CodeQuality\Rector\Property\TypedPropertyFromToManyRelationTypeRector\Fixture\ODM;
+
+use Doctrine\Common\Collections\ArrayCollection;
+use Doctrine\Common\Collections\Collection;
+use Rector\Doctrine\Tests\CodeQuality\Rector\Property\TypedPropertyFromToManyRelationTypeRector\Source\TrainingTerm;
+
+final class CollectionOfSuperClass
+{
+    /**
+     * @\Doctrine\ODM\MongoDB\Mapping\Annotations\EmbedMany()
+     * @var \Doctrine\Common\Collections\Collection
+     */
+    private \Doctrine\Common\Collections\Collection $trainingTerms;
+
+    public function __construct()
+    {
+    }
+}
+
+?>

src/NodeManipulator/ToManyRelationPropertyTypeResolver.php

@@ -7,6 +7,7 @@
 use PhpParser\Node\Expr;
 use PhpParser\Node\Param;
 use PhpParser\Node\Stmt\Property;
+use PHPStan\Type\ObjectType;
 use PHPStan\Type\Type;
 use Rector\BetterPhpDocParser\PhpDoc\ArrayItemNode;
 use Rector\BetterPhpDocParser\PhpDoc\DoctrineAnnotationTagValueNode;
@@ -65,7 +66,8 @@ private function processToManyRelation(
             EntityMappingKey::TARGET_ENTITY
         ) ?: $doctrineAnnotationTagValueNode->getValue(OdmMappingKey::TARGET_DOCUMENT);
         if (! $targetEntityArrayItemNode instanceof ArrayItemNode) {
-            return null;
+            // most likely mapped superclass
+            return new ObjectType(DoctrineClass::COLLECTION);
         }
 
         $targetEntityClass = $targetEntityArrayItemNode->value;