bug symfony#31026 [Serializer] Add default object class resolver (jdecool)

This PR was squashed before being merged into the 4.2 branch (closes symfony#31026). Discussion ---------- [Serializer] Add default object class resolver | Q | A | ------------- | --- | Branch? | 4.2 | Bug fix? | yes | New feature? | no | BC breaks? | no | Deprecations? | no | Tests pass? | yes | Fixed tickets | - | License | MIT | Doc PR | - The commit symfony@1d8b5af introduce a BC break because before that commit the `extractAttributes` the `$object` can be a string which contain the fully qualified name of an object. To fix the BC break and preserve the new feature, I suggest to create a default object class resolver if it is not set by the developer. Commits ------- dd5b8f1 [Serializer] Add default object class resolver

Author: fabpot

src/Symfony/Component/Serializer/Normalizer/ObjectNormalizer.php

@@ -43,7 +43,10 @@ public function __construct(ClassMetadataFactoryInterface $classMetadataFactory
  parent::__construct($classMetadataFactory, $nameConverter, $propertyTypeExtractor, $classDiscriminatorResolver, $objectClassResolver, $defaultContext);
 
  $this->propertyAccessor = $propertyAccessor ?: PropertyAccess::createPropertyAccessor();
- $this->objectClassResolver = $objectClassResolver;
+
+ $this->objectClassResolver = $objectClassResolver ?? function ($class) {
+ return \is_object($class) ? \get_class($class) : $class;
+ };
  }
 
  /**
@@ -63,7 +66,7 @@ protected function extractAttributes($object, $format = null, array $context = [
  $attributes = [];
 
  // methods
- $class = $this->objectClassResolver ? ($this->objectClassResolver)($object) : \get_class($object);
+ $class = ($this->objectClassResolver)($object);
  $reflClass = new \ReflectionClass($class);
 
  foreach ($reflClass->getMethods(\ReflectionMethod::IS_PUBLIC) as $reflMethod) {

src/Symfony/Component/Serializer/Tests/Normalizer/ObjectNormalizerTest.php

@@ -1043,6 +1043,30 @@ public function denormalize($propertyName, string $class = null, string $format
  $this->assertArrayHasKey('foo-Symfony\Component\Serializer\Tests\Normalizer\ObjectDummy-json-bar', $normalizer->normalize(new ObjectDummy(), 'json', ['foo' => 'bar']));
  }
 
+ public function testDefaultObjectClassResolver()
+ {
+ $normalizer = new ObjectNormalizer();
+
+ $obj = new ObjectDummy();
+ $obj->setFoo('foo');
+ $obj->bar = 'bar';
+ $obj->setBaz(true);
+ $obj->setCamelCase('camelcase');
+ $obj->unwantedProperty = 'notwanted';
+
+ $this->assertEquals(
+ [
+ 'foo' => 'foo',
+ 'bar' => 'bar',
+ 'baz' => true,
+ 'fooBar' => 'foobar',
+ 'camelCase' => 'camelcase',
+ 'object' => null,
+ ],
+ $normalizer->normalize($obj, 'any')
+ );
+ }
+
  public function testObjectClassResolver()
  {
  $classResolver = function ($object) {