merged branch jakzal/checkbox-type-false (PR #7789)

This PR was merged into the master branch.

Discussion
----------

[Form] Allowed binding false to a checkbox

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | yes
| Deprecations? | no
| Tests pass?   | [![Build Status](https://travis-ci.org/jakzal/symfony.png?branch=checkbox-type-false)](https://travis-ci.org/jakzal/symfony)
| Fixed tickets | #7139
| License       | MIT
| Doc PR        | -

Commits
-------

24ef8d2 [Form] Added a SimpleFormTest test case.
e493984 [Form] Allowed binding false to a checkbox.

src/Symfony/Component/Form/Form.php

@@ -488,11 +488,14 @@ class Form implements \IteratorAggregate, FormInterface
             $this->setData($this->config->getData());
         }
 
+        // Treat false as NULL to support binding false to checkboxes.
         // Don't convert NULL to a string here in order to determine later
         // whether an empty value has been submitted or whether no value has
         // been submitted at all. This is important for processing checkboxes
         // and radio buttons with empty values.
-        if (is_scalar($submittedData)) {
+        if (false === $submittedData) {
+            $submittedData = null;
+        } elseif (is_scalar($submittedData)) {
             $submittedData = (string) $submittedData;
         }
 

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

@@ -105,6 +105,28 @@ class CheckboxTypeTest extends \Symfony\Component\Form\Test\TypeTestCase
         $this->assertNull($form->getViewData());
     }
 
+    public function testBindWithEmptyValueAndFalseUnchecked()
+    {
+        $form = $this->factory->create('checkbox', null, array(
+            'value' => '',
+        ));
+        $form->bind(false);
+
+        $this->assertFalse($form->getData());
+        $this->assertNull($form->getViewData());
+    }
+
+    public function testBindWithEmptyValueAndTrueChecked()
+    {
+        $form = $this->factory->create('checkbox', null, array(
+            'value' => '',
+        ));
+        $form->bind(true);
+
+        $this->assertTrue($form->getData());
+        $this->assertSame('', $form->getViewData());
+    }
+
     /**
      * @dataProvider provideTransformedData
      */

src/Symfony/Component/Form/Tests/SimpleFormTest.php

@@ -96,6 +96,28 @@ class SimpleFormTest extends AbstractFormTest
         $form->bind('foobar');
     }
 
+    // https://github.com/symfony/symfony/pull/7789
+    public function testFalseIsConvertedToNull()
+    {
+        $mock = $this->getMockBuilder('\stdClass')
+            ->setMethods(array('preBind'))
+            ->getMock();
+        $mock->expects($this->once())
+            ->method('preBind')
+            ->with($this->callback(function ($event) {
+                return null === $event->getData();
+            }));
+
+        $config = new FormConfigBuilder('name', null, $this->dispatcher);
+        $config->addEventListener(FormEvents::PRE_BIND, array($mock, 'preBind'));
+        $form = new Form($config);
+
+        $form->bind(false);
+
+        $this->assertTrue($form->isValid());
+        $this->assertNull($form->getData());
+    }
+
     /**
      * @expectedException \Symfony\Component\Form\Exception\AlreadyBoundException
      */