Issue #2911149 by quietone, Jo Fitzgerald, heddn, cogent, mikelutz: FormatDate...

Issue #2911149 by quietone, Jo Fitzgerald, heddn, cogent, mikelutz: FormatDate process plugin doesn't handle zero values

core/modules/migrate/src/Plugin/migrate/process/FormatDate.php

@@ -82,7 +82,8 @@
  * @endcode
  *
  * If the source value was '2004-12-19T10:19:42-0600' the transformed value
- * would be 2004-12-19T10:19:42.
+ * would be 2004-12-19T10:19:42. Set validate_format to false if your source
+ * value is '0000-00-00 00:00:00'.
  *
  * @see \DateTime::createFromFormat()
  * @see \Drupal\Component\Datetime\DateTimePlus::__construct()
@@ -99,7 +100,7 @@ class FormatDate extends ProcessPluginBase {
    * {@inheritdoc}
    */
   public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
-    if (empty($value)) {
+    if (empty($value) && $value !== '0' && $value !== 0) {
       return '';
     }
 

core/modules/migrate/tests/src/Unit/process/FormatDateTest.php

@@ -189,6 +189,42 @@ public function datesDataProvider() {
         // converted from Australia/Sydney to America/Managua timezone.
         'expected' => '2004-12-18 17:19:42 America/Managua',
       ],
+      'integer_0' => [
+        'configuration' => [
+          'from_format' => 'U',
+          'to_format' => 'Y-m-d',
+        ],
+        'value' => 0,
+        'expected' => '1970-01-01',
+      ],
+      'string_0' => [
+        'configuration' => [
+          'from_format' => 'U',
+          'to_format' => 'Y-m-d',
+        ],
+        'value' => '0',
+        'expected' => '1970-01-01',
+      ],
+      'zeros' => [
+        'configuration' => [
+          'from_format' => 'Y-m-d H:i:s',
+          'to_format' => 'Y-m-d H:i:s e',
+          'settings' => ['validate_format' => FALSE],
+        ],
+        'value' => '0000-00-00 00:00:00',
+        'expected' => '-0001-11-30 00:00:00 Australia/Sydney',
+      ],
+      'zeros_same_timezone' => [
+        'configuration' => [
+          'from_format' => 'Y-m-d H:i:s',
+          'to_format' => 'Y-m-d H:i:s',
+          'settings' => ['validate_format' => FALSE],
+          'from_timezone' => 'UTC',
+          'to_timezone' => 'UTC',
+        ],
+        'value' => '0000-00-00 00:00:00',
+        'expected' => '-0001-11-30 00:00:00',
+      ],
     ];
   }