WordPress at a glance
function is not described

wp_make_theme_file_tree() WP 4.9.0

Makes a tree structure for the Theme Editor's file list.

No Hooks.

Return

Array. Tree structure for listing theme files.

Usage

wp_make_theme_file_tree( $allowed_files );
$allowed_files(array) (required)
List of theme file paths.

Code of wp make theme file tree: wp-admin/includes/misc.php VER 5.0.3

<?php
function wp_make_theme_file_tree( $allowed_files ) {
	$tree_list = array();
	foreach ( $allowed_files as $file_name => $absolute_filename ) {
		$list = explode( '/', $file_name );
		$last_dir = &$tree_list;
		foreach ( $list as $dir ) {
			$last_dir =& $last_dir[ $dir ];
		}
		$last_dir = $file_name;
	}
	return $tree_list;
}