Method depthOf

src/FileRise/Domain/DiskUsageModel.php:976–982

* Helper: approximate depth of a folder key (root->0, "foo"->1, "foo/bar"->2, etc.) */

(string $key)

     * Helper: approximate depth of a folder key (root->0, "foo"->1, "foo/bar"->2, etc.)
     */
    private static function depthOf(string $key): int
    {
        if ($key === '' || $key === 'root') {
            return 0;
        }
        return substr_count(trim($key, '/'), '/') + 1;
    }
}