Unescaping re-added, support limited to schema introspection (#2850 will bring...

Unescaping re-added, support limited to schema introspection (#2850 will bring more complete coverage)

lib/Doctrine/DBAL/Schema/MySqlSchemaManager.php

@@ -218,8 +218,9 @@ class MySqlSchemaManager extends AbstractSchemaManager
      *   to distinguish them from expressions (see MDEV-10134).
      * - CURRENT_TIMESTAMP, CURRENT_TIME, CURRENT_DATE are stored in information_schema
      *   as current_timestamp(), currdate(), currtime()
-     * - Note: Quoted 'NULL' is not enforced by Maria, it is technically possible to have
+     * - Quoted 'NULL' is not enforced by Maria, it is technically possible to have
      *   null in some circumstances (see https://jira.mariadb.org/browse/MDEV-14053)
+     * - \' is always stored as '' in information_schema (normalized)
      *
      * @link https://mariadb.com/kb/en/library/information-schema-columns-table/
      * @link https://jira.mariadb.org/browse/MDEV-13132
@@ -232,7 +233,11 @@ class MySqlSchemaManager extends AbstractSchemaManager
             return null;
         }
         if ($columnDefault[0] === "'") {
-            return preg_replace('/^\'(.*)\'$/', '$1', $columnDefault);
+            return stripslashes(
+                str_replace("''", "'",
+                    preg_replace('/^\'(.*)\'$/', '$1', $columnDefault)
+                )
+            );
         }
         switch ($columnDefault) {
             case 'current_timestamp()':

tests/Doctrine/Tests/DBAL/Functional/Schema/MySqlSchemaManagerTest.php

@@ -446,4 +446,25 @@ class MySqlSchemaManagerTest extends SchemaManagerFunctionalTestCase
         $diff = $comparator->diffTable($table, $onlineTable);
         self::assertFalse($diff, "Tables should be identical with column defauts time and date.");
     }
+
+    /**
+     * Ensure default values (un-)escaping is properly done by mysql platforms.
+     * The test is voluntarily relying on schema introspection due to current
+     * doctrine limitations. Once #2850 is landed, this test can be removed.
+     */
+    public function testEnsureDefaultsAreUnescapedFromSchemaIntrospection() : void
+    {
+        $platform = $this->_sm->getDatabasePlatform();
+        $this->_conn->query('DROP TABLE IF EXISTS test_column_defaults_with_create');
+
+        $default = "a\\0b\\'c\"d\te\\Zf\\\\g''h";
+        $sql = "CREATE TABLE test_column_defaults_with_create(
+                  col1 VARCHAR(255) NULL DEFAULT {$platform->quoteStringLiteral($default)} 
+               )";
+
+        $this->_conn->query($sql);
+
+        $onlineTable = $this->_sm->listTableDetails("test_column_defaults_with_create");
+        self::assertSame($default, $onlineTable->getColumn('col1')->getDefault());
+    }
 }