Fix flags preservation and move test to PDO core

Extract flags before resolving PDO_FETCH_USE_DEFAULT so caller-supplied
flags (e.g. PDO_FETCH_GROUP) are preserved. Move test from pdo_sqlite to
ext/pdo/tests/ for cross-driver coverage. Add test cases for query()
with second argument and flags preservation.

Author: iliaal

ext/pdo/pdo_stmt.c

@@ -1731,12 +1731,12 @@ bool pdo_stmt_setup_fetch_mode(pdo_stmt_t *stmt, zend_long mode, uint32_t mode_a
 
 	stmt->default_fetch_type = PDO_FETCH_BOTH;
 
+	flags = mode & PDO_FETCH_FLAGS;
+
 	if ((mode & ~PDO_FETCH_FLAGS) == PDO_FETCH_USE_DEFAULT) {
-		mode = stmt->dbh->default_fetch_type;
+		mode = stmt->dbh->default_fetch_type | flags;
 	}
 
-	flags = mode & PDO_FETCH_FLAGS;
-
 	if (!pdo_stmt_verify_mode(stmt, mode, mode_arg_num, false)) {
 		return false;
 	}

ext/pdo_sqlite/tests/gh20214.phpt ext/pdo/tests/gh20214.phptext/pdo_sqlite/tests/gh20214.phpt renamed to ext/pdo/tests/gh20214.phpt

@@ -1,10 +1,19 @@
 --TEST--
 GH-20214 (PDO::FETCH_DEFAULT unexpected behavior with PDOStatement::setFetchMode)
 --EXTENSIONS--
-pdo_sqlite
+pdo
+--SKIPIF--
+<?php
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
 --FILE--
 <?php
-$db = new PDO("sqlite::memory:");
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
 $db->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_OBJ);
 
 // setFetchMode with FETCH_DEFAULT should use connection default (FETCH_OBJ)
@@ -29,10 +38,25 @@ $stmt = $db->query("SELECT 'v1' AS c1, 'v2' AS c2");
 $stmt->setFetchMode(PDO::FETCH_DEFAULT);
 $row = $stmt->fetch();
 var_dump($row instanceof stdClass);
+
+// query() with FETCH_DEFAULT as second argument
+$db->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_NUM);
+$stmt = $db->query("SELECT 'v1' AS c1, 'v2' AS c2", PDO::FETCH_DEFAULT);
+$row = $stmt->fetch();
+var_dump(is_array($row) && isset($row[0]));
+
+// FETCH_DEFAULT with flags should preserve the flags
+$db->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
+$stmt = $db->query("SELECT 'v1' AS c1, 'v2' AS c2");
+$stmt->setFetchMode(PDO::FETCH_DEFAULT | PDO::FETCH_GROUP);
+$rows = $stmt->fetchAll();
+var_dump(is_array($rows) && array_key_exists('v1', $rows));
 ?>
 --EXPECT--
 bool(true)
 string(2) "v1"
 bool(true)
 bool(true)
 bool(true)
+bool(true)
+bool(true)