bug #11342 [2.3][Form] Check if IntlDateFormatter constructor returned a valid object before using it (romainneutron)

This PR was merged into the 2.3 branch.

Discussion
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[2.3][Form] Check if IntlDateFormatter constructor returned a valid object before using it

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | n/a
| License       | MIT

`IntlDateFormatter` constructor [may return false](http://www.php.net/manual/en/intldateformatter.create.php#refsect1-intldateformatter.create-returnvalues). This patches avoids fatal errors in these cases

This PR replaces #11334

Commits
-------

ebf967d [Form] Check if IntlDateFormatter constructor returned a valid object before using it

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

@@ -152,6 +152,8 @@ class DateTimeToLocalizedStringTransformer extends BaseDateTimeTransformer
      * Returns a preconfigured IntlDateFormatter instance
      *
      * @return \IntlDateFormatter
+     *
+     * @throws TransformationFailedException in case the date formatter can not be constructed.
      */
     protected function getIntlDateFormatter()
     {
@@ -162,6 +164,12 @@ class DateTimeToLocalizedStringTransformer extends BaseDateTimeTransformer
         $pattern = $this->pattern;
 
         $intlDateFormatter = new \IntlDateFormatter(\Locale::getDefault(), $dateFormat, $timeFormat, $timezone, $calendar, $pattern);
+
+        // new \intlDateFormatter may return null instead of false in case of failure, see https://bugs.php.net/bug.php?id=66323
+        if (!$intlDateFormatter) {
+            throw new TransformationFailedException(intl_get_error_message(), intl_get_error_code());
+        }
+
         $intlDateFormatter->setLenient(false);
 
         return $intlDateFormatter;

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

@@ -77,6 +77,12 @@ class DateType extends AbstractType
                 $calendar,
                 $pattern
             );
+
+            // new \intlDateFormatter may return null instead of false in case of failure, see https://bugs.php.net/bug.php?id=66323
+            if (!$formatter) {
+                throw new InvalidOptionsException(intl_get_error_message(), intl_get_error_code());
+            }
+
             $formatter->setLenient(false);
 
             if ('choice' === $options['widget']) {