Run tests with PHP 8.5 (#2917)

* Test with PHP 8.5
* Fix 'Using null as an array offset is deprecated, use an empty string instead'

---------

Co-authored-by: Ion Bazan <[email protected]>

Author: GromNaN

.github/workflows/continuous-integration.yml

@@ -23,6 +23,7 @@ jobs:
           - "8.2"
           - "8.3"
           - "8.4"
+          - "8.5"
         mongodb-version:
           - "8.0"
           - "7.0"

src/Aggregation/Stage/VectorSearch.php

@@ -82,7 +82,7 @@ public function getExpression(): array
         }
 
         if ($this->queryVector !== null) {
-            $params['queryVector'] = Type::getType($this->persister->getClassMetadata()->fieldMappings[$this->path]['type'] ?? Type::RAW)->convertToDatabaseValue($this->queryVector);
+            $params['queryVector'] = Type::getType($this->persister->getClassMetadata()->fieldMappings[$this->path ?? '']['type'] ?? Type::RAW)->convertToDatabaseValue($this->queryVector);
         }
 
         return [$this->getStageName() => $params];

src/Persisters/DocumentPersister.php

@@ -706,7 +706,7 @@ private function loadEmbedManyCollection(PersistentCollectionInterface $collecti
             $this->uow->setParentAssociation($embeddedDocumentObject, $mapping, $owner, $mapping['name'] . '.' . $key);
 
             $data = $this->hydratorFactory->hydrate($embeddedDocumentObject, $embeddedDocument, $collection->getHints());
-            $id   = $data[$embeddedMetadata->identifier] ?? null;
+            $id   = $data[$embeddedMetadata->identifier ?? ''] ?? null;
 
             if (empty($collection->getHints()[Query::HINT_READ_ONLY])) {
                 $this->uow->registerManaged($embeddedDocumentObject, $id, $data);
@@ -994,7 +994,7 @@ public function prepareFieldName(string $fieldName): string
      */
     public function addDiscriminatorToPreparedQuery(array $preparedQuery): array
     {
-        if (isset($preparedQuery[$this->class->discriminatorField]) || $this->class->discriminatorField === null) {
+        if ($this->class->discriminatorField === null || isset($preparedQuery[$this->class->discriminatorField])) {
             return $preparedQuery;
         }