Introspect default expressions as DefaultExpression

src/Schema/MySQLSchemaManager.php

@@ -14,6 +14,9 @@
 use Doctrine\DBAL\Platforms\MySQL\CollationMetadataProvider\ConnectionCollationMetadataProvider;
 use Doctrine\DBAL\Platforms\MySQL\DefaultTableOptions;
 use Doctrine\DBAL\Result;
+use Doctrine\DBAL\Schema\DefaultExpression\CurrentDate;
+use Doctrine\DBAL\Schema\DefaultExpression\CurrentTime;
+use Doctrine\DBAL\Schema\DefaultExpression\CurrentTimestamp;
 use Doctrine\DBAL\Types\Type;
 
 use function array_change_key_case;
@@ -187,10 +190,12 @@ protected function _getPortableTableColumnDefinition(array $tableColumn): Column
                 break;
         }
 
-        if ($this->platform instanceof MariaDBPlatform) {
-            $columnDefault = $this->getMariaDBColumnDefault($this->platform, $tableColumn['default']);
+        if ($tableColumn['default'] === null) {
+            $columnDefault = null;
+        } elseif ($this->platform instanceof MariaDBPlatform) {
+            $columnDefault = $this->parseMariaDBColumnDefault($tableColumn['default']);
         } else {
-            $columnDefault = $tableColumn['default'];
+            $columnDefault = $this->parseMySQLColumnDefault($dbType, $tableColumn['default']);
         }
 
         $options = [
@@ -228,6 +233,19 @@ private function parseEnumExpression(string $expression): array
         );
     }
 
+    /** @link https://dev.mysql.com/doc/refman/8.4/en/timestamp-initialization.html */
+    private function parseMySQLColumnDefault(string $type, string $default): string|DefaultExpression
+    {
+        // There is no way to tell whether the "CURRENT_TIMESTAMP" value represents a string or an expression in MySQL
+        // schema introspection results. We rely on the fact that the "CURRENT_TIMESTAMP" expression is only supported
+        // for the "DATETIME" and "TIMESTAMP" data types and represent this value as an expression only in these cases.
+        if (($type === 'datetime' || $type === 'timestamp') && $default === 'CURRENT_TIMESTAMP') {
+            return new CurrentTimestamp();
+        }
+
+        return $default;
+    }
+
     /**
      * Return Doctrine/Mysql-compatible column default values for MariaDB 10.2.7+ servers.
      *
@@ -242,11 +260,11 @@ private function parseEnumExpression(string $expression): array
      * @link https://mariadb.com/kb/en/library/information-schema-columns-table/
      * @link https://jira.mariadb.org/browse/MDEV-13132
      *
-     * @param string|null $columnDefault default value as stored in information_schema for MariaDB >= 10.2.7
+     * @param string $columnDefault default value as stored in information_schema for MariaDB >= 10.2.7
      */
-    private function getMariaDBColumnDefault(MariaDBPlatform $platform, ?string $columnDefault): ?string
+    private function parseMariaDBColumnDefault(string $columnDefault): string|DefaultExpression|null
     {
-        if ($columnDefault === 'NULL' || $columnDefault === null) {
+        if ($columnDefault === 'NULL') {
             return null;
         }
 
@@ -255,9 +273,9 @@ private function getMariaDBColumnDefault(MariaDBPlatform $platform, ?string $col
         }
 
         return match ($columnDefault) {
-            'current_timestamp()' => $platform->getCurrentTimestampSQL(),
-            'curdate()' => $platform->getCurrentDateSQL(),
-            'curtime()' => $platform->getCurrentTimeSQL(),
+            'current_timestamp()' => new CurrentTimestamp(),
+            'curdate()' => new CurrentDate(),
+            'curtime()' => new CurrentTime(),
             default => $columnDefault,
         };
     }

src/Schema/SQLServerSchemaManager.php

@@ -8,6 +8,7 @@
 use Doctrine\DBAL\Platforms\SQLServer;
 use Doctrine\DBAL\Platforms\SQLServerPlatform;
 use Doctrine\DBAL\Result;
+use Doctrine\DBAL\Schema\DefaultExpression\CurrentTimestamp;
 use Doctrine\DBAL\Types\Type;
 
 use function array_change_key_case;
@@ -148,7 +149,7 @@ protected function _getPortableTableColumnDefinition(array $tableColumn): Column
         return $column;
     }
 
-    private function parseDefaultExpression(string $value): ?string
+    private function parseDefaultExpression(string $value): string|DefaultExpression|null
     {
         while (preg_match('/^\((.*)\)$/s', $value, $matches) === 1) {
             $value = $matches[1];
@@ -163,7 +164,7 @@ private function parseDefaultExpression(string $value): ?string
         }
 
         if ($value === 'getdate()') {
-            return $this->platform->getCurrentTimestampSQL();
+            return new CurrentTimestamp();
         }
 
         return $value;