Update src/Symfony/Component/Form/Extension/Core/Type/FileType.php

src/Symfony/Component/Form/Extension/Core/Type/FileType.php

@@ -46,6 +46,7 @@ class FileType extends AbstractType
     {
         $resolver->setDefaults(array(
             'compound' => false,
+            'data_class' => 'Symfony\Component\HttpFoundation\File\File'        
         ));
     }
 

src/Symfony/Component/Form/Tests/Extension/Core/Type/FileTypeTest.php

@@ -15,6 +15,22 @@ use Symfony\Component\HttpFoundation\File\UploadedFile;
 
 class FileTypeTest extends TypeTestCase
 {
+
+    public function testFormBuilderIfEntityHasFile()
+    {
+        $entity = new \StdClass;
+        $entity->imageFile = $this->createUploadedFileMock('abcdef', 'original.jpg', true);
+
+        try {
+            $form = $this->factory->createBuilder('form', $entity)
+                ->add('imageFile', 'file')
+                ->getForm();
+            return;
+        } catch (\Symfony\Component\Form\Exception\FormException $e) {
+            $this->fail();
+        }
+    }
+
     public function testDontPassValueToView()
     {
         $form = $this->factory->create('file');