- The return type of return $stmtWrapper; (Kir\MySQL\Builder\QueryStatement) is incompatible with the return type declared by the interface Kir\MySQL\Database::query of type PDOStatement.

- The return type of return $stmtWrapper; (Kir\MySQL\Builder\QueryStatement) is incompatible with the return type declared by the interface Kir\MySQL\Database::prepare of type PDOStatement.
- The expression preg_replace_callback(&#...;, $func, $expression); of type string|string[] adds the type string[] to the return on line 149 which is incompatible with the return type declared by the interface Kir\MySQL\Database::quoteExpression of type string.

Author: rkrx

src/Database.php

@@ -2,6 +2,7 @@
 namespace Kir\MySQL;
 
 use Kir\MySQL\Builder\Exception;
+use Kir\MySQL\Builder\QueryStatement;
 use Kir\MySQL\Builder\RunnableSelect;
 use Kir\MySQL\Tools\AliasRegistry;
 
@@ -14,14 +15,14 @@ public function getAliasRegistry();
 	/**
 	 * @param string $query
 	 * @throws Exception
-	 * @return \PDOStatement
+	 * @return QueryStatement
 	 */
 	public function query($query);
 
 	/**
 	 * @param string $query
 	 * @throws Exception
-	 * @return \PDOStatement
+	 * @return QueryStatement
 	 */
 	public function prepare($query);
 

src/Databases/MySQL.php

@@ -146,7 +146,8 @@ public function quoteExpression($expression, array $arguments = array()) {
 			}
 			return $value;
 		};
-		return preg_replace_callback('/(\\?|:\\d+)/', $func, $expression);
+		$result = preg_replace_callback('/(\\?|:\\d+)/', $func, $expression);
+		return (string) $result;
 	}
 
 	/**