wp-includes/formatting.php:5676i18n-friendly version of basename().
$pathstring$suffixstringoptional''stringfunction wp_basename( $path, $suffix = '' ) { return urldecode( basename( str_replace( array( '%2F', '%5C' ), '/', urlencode( $path ) ), $suffix ) );}Introduced in 3.1.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/formatting.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.