private function groupIdsByFile(array $ids) : array
    {
        $covered = [];

        foreach ($ids as $id) {
            $file = mb_substr($id, 0, (int) mb_strpos($id, '::'));

            if (!isset($covered[$file])) {
                $covered[$file] = [];
            }

            $covered[$file][] = mb_substr($id, mb_strpos($id, '::') + 2);
        }

        return $covered;
    }