wp-includes/PHPMailer/PHPMailer.php:4664Map a file name to a MIME type.
$filenamestringstring public static function filenameToType($filename) { //In case the path is a URL, strip any query string before getting extension $qpos = strpos($filename, '?'); if (false !== $qpos) { $filename = substr($filename, 0, $qpos); } $ext = static::mb_pathinfo($filename, PATHINFO_EXTENSION); return static::_mime_types($ext); }Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/PHPMailer/PHPMailer.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.