public function provideFilesToCheck()
    {
        $iterator = new AppendIterator();

        foreach ($this->getPaths() as $path) {
            $iterator->append(new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path)));
        }

        $files = new CallbackFilterIterator($iterator, function ($file) {
            return $file->getFilename()[0] !== '.' && !$file->isDir();
        });

        return array_map(function ($file) {
            return [(string) $file];
        }, iterator_to_array($files));
    }