Fix PHP 8.5 + symfony deprecations

src/SerializationContext.php

@@ -68,7 +68,7 @@ public function startVisiting($object): void
             return;
         }
 
-        $this->visitingSet->attach($object);
+        $this->visitingSet->offsetSet($object);
         $this->visitingStack->push($object);
     }
 
@@ -81,7 +81,7 @@ public function stopVisiting($object): void
             return;
         }
 
-        $this->visitingSet->detach($object);
+        $this->visitingSet->offsetUnset($object);
         $poppedObject = $this->visitingStack->pop();
 
         if ($object !== $poppedObject) {
@@ -98,7 +98,7 @@ public function isVisiting($object): bool
             return false;
         }
 
-        return $this->visitingSet->contains($object);
+        return $this->visitingSet->offsetExists($object);
     }
 
     public function getPath(): ?string

tests/Handler/FormErrorHandlerTest.php

@@ -98,7 +98,7 @@ public function testSerializeFormWithData()
         $builder->add('url', TextType::class);
         $builder->add('txt', TextType::class, [
             'constraints' => [
-                new Length(['min' => 10]),
+                new Length(null, 10),
             ],
         ]);
 

tests/Serializer/BaseSerializationTestCase.php

@@ -851,7 +851,7 @@ public function testNamedDateTimeImmutableArrays()
 
             /** deserialized object has a default timezone set depending on user's timezone settings. That's why we manually set the UTC timezone on the DateTime objects. */
             foreach ($deserializedObject->getNamedArrayWithFormattedDate() as $dateTime) {
-                $dateTime->setTimezone(new \DateTimeZone('UTC'));
+                $dateTime = $dateTime->setTimezone(new \DateTimeZone('UTC'));
             }
 
             self::assertEquals($object, $deserializedObject);