[Form] Fixed: NumberToLocalizedStringTransformer does not accept "NaN" as valid number anymore

src/Symfony/Component/Form/Extension/Core/DataTransformer/NumberToLocalizedStringTransformer.php

@@ -103,6 +103,10 @@ class NumberToLocalizedStringTransformer implements DataTransformerInterface
             return null;
         }
 
+        if ('NaN' === $value) {
+            throw new TransformationFailedException('"NaN" is not a valid number');
+        }
+
         $formatter = $this->getNumberFormatter();
         $value = $formatter->parse($value);
 

tests/Symfony/Tests/Component/Form/Extension/Core/DataTransformer/NumberToLocalizedStringTransformerTest.php

@@ -128,10 +128,20 @@ class NumberToLocalizedStringTransformerTest extends LocalizedTestCase
      * @expectedException Symfony\Component\Form\Exception\TransformationFailedException
      * @link https://github.com/symfony/symfony/issues/3161
      */
-    public function testReverseTransformExpectsValidNumberFromNan()
+    public function testReverseTransformDisallowsNaN()
     {
         $transformer = new NumberToLocalizedStringTransformer();
 
         $transformer->reverseTransform('NaN');
     }
+
+    /**
+     * @expectedException Symfony\Component\Form\Exception\TransformationFailedException
+     */
+    public function testReverseTransformDisallowsNaN2()
+    {
+        $transformer = new NumberToLocalizedStringTransformer();
+
+        $transformer->reverseTransform('nan');
+    }
 }