Fixing getParent method for 2.8 version compatibility.

Author: abdielcs

Form/Type/ExpandedMTMType.php

@@ -14,7 +14,6 @@
 use abdielcs\ExpandedCollectionBundle\Form\DataTransformer\MiddleClassTransformer;
 use Symfony\Component\Form\AbstractType;
 use Symfony\Component\Form\FormBuilderInterface;
-use Symfony\Component\HttpKernel\Kernel;
 use Symfony\Component\OptionsResolver\OptionsResolver;
 use Symfony\Component\OptionsResolver\OptionsResolverInterface;
 
@@ -36,8 +35,8 @@ public function buildForm(FormBuilderInterface $builder, array $options)
 
     public function getParent()
     {
-        if (Kernel::MAJOR_VERSION > 2) {
-            return ExpandedOTMType::class ;
+        if (method_exists('Symfony\Component\Form\AbstractType', 'getBlockPrefix')) {
+            return ExpandedOTMType::class;
         } else {
             return 'expanded_otm';
         }

Form/Type/ExpandedOTMType.php

@@ -15,7 +15,6 @@
 use Symfony\Component\Form\AbstractType;
 use Symfony\Component\Form\FormInterface;
 use Symfony\Component\Form\FormView;
-use Symfony\Component\HttpKernel\Kernel;
 use Symfony\Component\OptionsResolver\OptionsResolver;
 use Symfony\Component\OptionsResolver\OptionsResolverInterface;
 
@@ -28,7 +27,7 @@ class ExpandedOTMType extends AbstractType
 {
     public function getParent()
     {
-        if (Kernel::MAJOR_VERSION > 2) {
+        if (method_exists('Symfony\Component\Form\AbstractType', 'getBlockPrefix')) {
             return EntityType::class;
         } else {
             return 'entity';