Avoid UNKNOWN default in PDO::query()

Author: nikic

UPGRADING

@@ -350,9 +350,11 @@ PHP 8.0 UPGRADE NOTES
     "exceptions". See https://www.php.net/manual/en/pdo.error-handling.php
     for details of behavior changes and how to explicitly set this attribute.
     RFC: https://wiki.php.net/rfc/pdo_default_errmode
-  . The method PDOStatement::setFetchMode() now accepts the following signature:
+  . The signatures of some PDO methods have changed:
 
-        PDOStatement::setFetchMode($mode, $classname, $params)
+        PDO::query(
+            string $statement, ?int $fetch_mode = null, ...$fetch_mode_args)
+        PDOStatement::setFetchMode(int $mode, ...$params)
 
 - PDO_ODBC:
   . The php.ini directive pdo_odbc.db2_instance_name has been removed

ext/pdo/pdo_dbh.c

@@ -1026,12 +1026,13 @@ PHP_METHOD(PDO, query)
 	char *statement;
 	size_t statement_len;
 	zend_long fetch_mode;
+	zend_bool fetch_mode_is_null = 1;
 	zval *args = NULL;
 	uint32_t num_args = 0;
 	pdo_dbh_object_t *dbh_obj = Z_PDO_OBJECT_P(ZEND_THIS);
 	pdo_dbh_t *dbh = dbh_obj->inner;
 
-	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "s|l*", &statement, &statement_len, &fetch_mode, &args, &num_args)) {
+	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "s|l!*", &statement, &statement_len, &fetch_mode, &fetch_mode_is_null, &args, &num_args)) {
 		RETURN_THROWS();
 	}
 
@@ -1061,7 +1062,7 @@ PHP_METHOD(PDO, query)
 
 	if (dbh->methods->preparer(dbh, statement, statement_len, stmt, NULL)) {
 		PDO_STMT_CLEAR_ERR();
-		if (ZEND_NUM_ARGS() == 1 || SUCCESS == pdo_stmt_setup_fetch_mode(stmt, fetch_mode, args, num_args)) {
+		if (fetch_mode_is_null || SUCCESS == pdo_stmt_setup_fetch_mode(stmt, fetch_mode, args, num_args)) {
 
 			/* now execute the statement */
 			PDO_STMT_CLEAR_ERR();

ext/pdo/pdo_dbh.stub.php

@@ -37,7 +37,7 @@ public function lastInsertId(?string $name = null) {}
     public function prepare(string $statement, array $driver_options = []) {}
 
     /** @return PDOStatement|false */
-    public function query(string $statement, int $fetch_mode = UNKNOWN, ...$fetch_mode_args) {}
+    public function query(string $statement, ?int $fetch_mode = null, ...$fetch_mode_args) {}
 
     /** @return string|false */
     public function quote(string $string, int $parameter_type = PDO::PARAM_STR) {}

ext/pdo/pdo_dbh_arginfo.h

@@ -1,5 +1,5 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: c329bfda55244467a2cd62f9d5c5120ec3f24eef */
+ * Stub hash: 36270d1418fc4ddd8f79018372b0ef00fb6f5889 */
 
 ZEND_BEGIN_ARG_INFO_EX(arginfo_class_PDO___construct, 0, 0, 1)
 	ZEND_ARG_TYPE_INFO(0, dsn, IS_STRING, 0)
@@ -40,7 +40,7 @@ ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_INFO_EX(arginfo_class_PDO_query, 0, 0, 1)
 	ZEND_ARG_TYPE_INFO(0, statement, IS_STRING, 0)
-	ZEND_ARG_TYPE_INFO(0, fetch_mode, IS_LONG, 0)
+	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, fetch_mode, IS_LONG, 1, "null")
 	ZEND_ARG_VARIADIC_INFO(0, fetch_mode_args)
 ZEND_END_ARG_INFO()
 

ext/pdo/tests/bug_44173.phpt

@@ -54,7 +54,7 @@ var_dump($stmt);
 --EXPECTF--
 Warning: PDO::query(): SQLSTATE[HY000]: General error: fetch mode doesn't allow any extra arguments in %s
 bool(false)
-PDO::query(): Argument #2 ($fetch_mode) must be of type int, string given
+PDO::query(): Argument #2 ($fetch_mode) must be of type ?int, string given
 
 Warning: PDO::query(): SQLSTATE[HY000]: General error: too many arguments in %s
 bool(false)