Use instanceof check for native lexer fast path

When the native extension is loaded, WP_MySQL_Lexer extends
WP_MySQL_Native_Lexer, so an instanceof check is more direct than
method_exists() — and it gives the IDE/static analyzer something to
work with.

Author: adamziel

packages/mysql-on-sqlite/src/sqlite/class-wp-pdo-mysql-on-sqlite.php

@@ -1158,7 +1158,7 @@ public function create_parser( string $query ): WP_MySQL_Parser {
 			80038,
 			$this->active_sql_modes
 		);
-		if ( method_exists( $lexer, 'native_token_stream' ) ) {
+		if ( $lexer instanceof WP_MySQL_Native_Lexer ) {
 			$tokens = $lexer->native_token_stream();
 			return new WP_MySQL_Parser( self::$mysql_grammar, $tokens );
 		}

packages/mysql-on-sqlite/tests/tools/run-parser-benchmark.php

@@ -56,7 +56,7 @@ function get_stats( $total, $failures, $exceptions ) {
 
 	try {
 		$lexer  = new WP_MySQL_Lexer( $query );
-		$tokens = method_exists( $lexer, 'native_token_stream' )
+		$tokens = $lexer instanceof WP_MySQL_Native_Lexer
 			? $lexer->native_token_stream()
 			: $lexer->remaining_tokens();
 		if ( ( is_array( $tokens ) ? count( $tokens ) : $tokens->count() ) === 0 ) {