wp-includes/functions.php:2847Helper function to check if a file name could match an existing image sub-size file name.
$filenamestring$filesarrayboolfunction _wp_check_existing_file_names( $filename, $files ) { $fname = pathinfo( $filename, PATHINFO_FILENAME ); $ext = pathinfo( $filename, PATHINFO_EXTENSION ); // Edge case, file names like `.ext`. if ( empty( $fname ) ) { return false; } if ( $ext ) { $ext = ".$ext"; } $regex = '/^' . preg_quote( $fname ) . '-(?:\d+x\d+|scaled|rotated)' . preg_quote( $ext ) . '$/i'; foreach ( $files as $file ) { if ( preg_match( $regex, $file ) ) { return true; } } return false;}Introduced in 5.3.1. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/functions.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.