[Form][DX] FileType "multiple" fixes

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

@@ -12,12 +12,37 @@
 namespace Symfony\Component\Form\Extension\Core\Type;
 
 use Symfony\Component\Form\AbstractType;
+use Symfony\Component\Form\FormBuilderInterface;
+use Symfony\Component\Form\FormEvent;
+use Symfony\Component\Form\FormEvents;
 use Symfony\Component\Form\FormInterface;
 use Symfony\Component\Form\FormView;
+use Symfony\Component\OptionsResolver\Options;
 use Symfony\Component\OptionsResolver\OptionsResolver;
 
 class FileType extends AbstractType
 {
+    /**
+     * {@inheritdoc}
+     */
+    public function buildForm(FormBuilderInterface $builder, array $options)
+    {
+        if ($options['multiple']) {
+            $builder->addEventListener(FormEvents::PRE_SUBMIT, function (FormEvent $event) {
+                $form = $event->getForm();
+                $data = $event->getData();
+
+                // submitted data for an input file (not required) without choosing any file
+                if (array(null) === $data) {
+                    $emptyData = $form->getConfig()->getEmptyData();
+
+                    $data = is_callable($emptyData) ? call_user_func($emptyData, $form, $data) : $emptyData;
+                    $event->setData($data);
+                }
+            });
+        }
+    }
+
     /**
      * {@inheritdoc}
      */
@@ -39,9 +64,7 @@ class FileType extends AbstractType
      */
     public function finishView(FormView $view, FormInterface $form, array $options)
     {
-        $view
+        $view->vars['multipart'] = true;
-            ->vars['multipart'] = true
-        ;
     }
 
     /**
@@ -49,10 +72,18 @@ class FileType extends AbstractType
      */
     public function configureOptions(OptionsResolver $resolver)
     {
+        $dataClass = function (Options $options) {
+            return $options['multiple'] ? null : 'Symfony\Component\HttpFoundation\File\File';
+        };
+
+        $emptyData = function (Options $options) {
+            return $options['multiple'] ? array() : null;
+        };
+
         $resolver->setDefaults(array(
             'compound' => false,
-            'data_class' => 'Symfony\Component\HttpFoundation\File\File',
+            'data_class' => $dataClass,
-            'empty_data' => null,
+            'empty_data' => $emptyData,
             'multiple' => false,
         ));
     }

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

@@ -44,6 +44,33 @@ class FileTypeTest extends \Symfony\Component\Form\Test\TypeTestCase
         $this->assertNull($form->getData());
     }
 
+    public function testSubmitEmptyMultiple()
+    {
+        $form = $this->factory->createBuilder('file', null, array(
+            'multiple' => true,
+        ))->getForm();
+
+        // submitted data when an input file is uploaded without choosing any file
+        $form->submit(array(null));
+
+        $this->assertSame(array(), $form->getData());
+    }
+
+    public function testSetDataMultiple()
+    {
+        $form = $this->factory->createBuilder('file', null, array(
+            'multiple' => true,
+        ))->getForm();
+
+        $data = array(
+            $this->createUploadedFileMock('abcdef', 'first.jpg', true),
+            $this->createUploadedFileMock('zyxwvu', 'second.jpg', true),
+        );
+
+        $form->setData($data);
+        $this->assertSame($data, $form->getData());
+    }
+
     public function testSubmitMultiple()
     {
         $form = $this->factory->createBuilder('file', null, array(