[Form] issue-13589: adding custom false-values to BooleanToString transformer

Author: leberknecht

CHANGELOG.md

@@ -19,6 +19,7 @@ CHANGELOG
  * removed passing guesser services ids as the fourth argument of `DependencyInjectionExtension::__construct()`
  * removed the ability to validate an unsubmitted form.
  * removed `ChoiceLoaderInterface` implementation in `TimezoneType`
+ * added the `false_values` option to the `CheckboxType` which allows to configure custom values which will be treated as `false` during submission
 
 3.4.0
 -----

Extension/Core/DataTransformer/BooleanToStringTransformer.php

@@ -12,6 +12,7 @@
 namespace Symfony\Component\Form\Extension\Core\DataTransformer;
 
 use Symfony\Component\Form\DataTransformerInterface;
+use Symfony\Component\Form\Exception\InvalidArgumentException;
 use Symfony\Component\Form\Exception\TransformationFailedException;
 
 /**
@@ -24,12 +25,19 @@ class BooleanToStringTransformer implements DataTransformerInterface
 {
     private $trueValue;
 
+    private $falseValues;
+
     /**
-     * @param string $trueValue The value emitted upon transform if the input is true
+     * @param string $trueValue   The value emitted upon transform if the input is true
+     * @param array  $falseValues
      */
-    public function __construct(string $trueValue)
+    public function __construct(string $trueValue, array $falseValues = array(null))
     {
         $this->trueValue = $trueValue;
+        $this->falseValues = $falseValues;
+        if (in_array($this->trueValue, $this->falseValues, true)) {
+            throw new InvalidArgumentException('The specified "true" value is contained in the false-values');
+        }
     }
 
     /**
@@ -65,7 +73,7 @@ public function transform($value)
      */
     public function reverseTransform($value)
     {
-        if (null === $value) {
+        if (in_array($value, $this->falseValues, true)) {
             return false;
         }
 

Extension/Core/Type/CheckboxType.php

@@ -32,7 +32,7 @@ public function buildForm(FormBuilderInterface $builder, array $options)
         // We cannot solve this case via overriding the "data" option, because
         // doing so also calls setDataLocked(true).
         $builder->setData(isset($options['data']) ? $options['data'] : false);
-        $builder->addViewTransformer(new BooleanToStringTransformer($options['value']));
+        $builder->addViewTransformer(new BooleanToStringTransformer($options['value'], $options['false_values']));
     }
 
     /**
@@ -59,7 +59,10 @@ public function configureOptions(OptionsResolver $resolver)
             'value' => '1',
             'empty_data' => $emptyData,
             'compound' => false,
+            'false_values' => array(null),
         ));
+
+        $resolver->setAllowedTypes('false_values', 'array');
     }
 
     /**

Tests/Extension/Core/DataTransformer/BooleanToStringTransformerTest.php

@@ -68,4 +68,26 @@ public function testReverseTransform()
         $this->assertTrue($this->transformer->reverseTransform(''));
         $this->assertFalse($this->transformer->reverseTransform(null));
     }
+
+    public function testCustomFalseValues()
+    {
+        $customFalseTransformer = new BooleanToStringTransformer(self::TRUE_VALUE, array('0', 'myFalse', true));
+        $this->assertFalse($customFalseTransformer->reverseTransform('myFalse'));
+        $this->assertFalse($customFalseTransformer->reverseTransform('0'));
+        $this->assertFalse($customFalseTransformer->reverseTransform(true));
+    }
+
+    /**
+     * @expectedException \Symfony\Component\Form\Exception\InvalidArgumentException
+     */
+    public function testTrueValueContainedInFalseValues()
+    {
+        new BooleanToStringTransformer('0', array(null, '0'));
+    }
+
+    public function testBeStrictOnTrueInFalseValueCheck()
+    {
+        $transformer = new BooleanToStringTransformer('0', array(null, false));
+        $this->assertInstanceOf(BooleanToStringTransformer::class, $transformer);
+    }
 }

Tests/Extension/Core/Type/CheckboxTypeTest.php

@@ -173,6 +173,38 @@ public function provideCustomModelTransformerData()
         );
     }
 
+    /**
+     * @dataProvider provideCustomFalseValues
+     */
+    public function testCustomFalseValues($falseValue)
+    {
+        $form = $this->factory->create(static::TESTED_TYPE, null, array(
+            'false_values' => array($falseValue),
+        ));
+        $form->submit($falseValue);
+        $this->assertFalse($form->getData());
+    }
+
+    public function provideCustomFalseValues()
+    {
+        return array(
+            array(''),
+            array('false'),
+            array('0'),
+        );
+    }
+
+    /**
+     * @expectedException \Symfony\Component\OptionsResolver\Exception\InvalidOptionsException
+     */
+    public function testDontAllowNonArrayFalseValues()
+    {
+        $this->expectExceptionMessageRegExp('/"false_values" with value "invalid" is expected to be of type "array"/');
+        $this->factory->create(static::TESTED_TYPE, null, array(
+            'false_values' => 'invalid',
+        ));
+    }
+
     public function testSubmitNull($expected = null, $norm = null, $view = null)
     {
         parent::testSubmitNull(false, false, null);