Merge branch '5.2' into 5.3

* 5.2:
  [Form] fix support for years outside of the 32b range on x86 arch
  Add an upgrade note about the removal of Serializable

Author: nicolas-grekas

DateFormatter/IntlDateFormatter.php

@@ -182,7 +182,7 @@ public static function create(?string $locale, ?int $datetype, ?int $timetype, $
     /**
      * Format the date/time value (timestamp) as a string.
      *
-     * @param int|\DateTimeInterface $timestamp The timestamp to format
+     * @param int|string|\DateTimeInterface $timestamp The timestamp to format
      *
      * @return string|bool The formatted value or false if formatting failed
      *
@@ -194,11 +194,15 @@ public function format($timestamp)
     {
         // intl allows timestamps to be passed as arrays - we don't
         if (\is_array($timestamp)) {
-            $message = 'Only integer Unix timestamps and DateTime objects are supported';
+            $message = 'Only Unix timestamps and DateTime objects are supported';
 
             throw new MethodArgumentValueNotImplementedException(__METHOD__, 'timestamp', $timestamp, $message);
         }
 
+        if (\is_string($timestamp) && $dt = \DateTime::createFromFormat('U', $timestamp)) {
+            $timestamp = $dt;
+        }
+
         // behave like the intl extension
         $argumentError = null;
         if (!\is_int($timestamp) && !$timestamp instanceof \DateTimeInterface) {
@@ -214,7 +218,7 @@ public function format($timestamp)
         }
 
         if ($timestamp instanceof \DateTimeInterface) {
-            $timestamp = $timestamp->getTimestamp();
+            $timestamp = $timestamp->format('U');
         }
 
         $transformer = new FullTransformer($this->getPattern(), $this->getTimeZoneId());
@@ -585,8 +589,7 @@ public function setTimeZone($timeZone)
      */
     protected function createDateTime(int $timestamp)
     {
-        $dateTime = new \DateTime();
-        $dateTime->setTimestamp($timestamp);
+        $dateTime = \DateTime::createFromFormat('U', $timestamp);
         $dateTime->setTimezone($this->dateTimeZone);
 
         return $dateTime;

Tests/DateFormatter/IntlDateFormatterTest.php

@@ -75,7 +75,7 @@ public function testFormatWithUnsupportedTimestampArgument()
         } catch (\Exception $e) {
             $this->assertInstanceOf(MethodArgumentValueNotImplementedException::class, $e);
 
-            $this->assertStringEndsWith('Only integer Unix timestamps and DateTime objects are supported.  Please install the "intl" extension for full localization capabilities.', $e->getMessage());
+            $this->assertStringEndsWith('Only Unix timestamps and DateTime objects are supported.  Please install the "intl" extension for full localization capabilities.', $e->getMessage());
         }
     }