@DataProvider(name = "group_tests")
    public Iterator<Object[]> groupCommandsData() throws IOException {
        CSVReader csvReader = new CSVReader(new FileReader(TESTS_FILENAME));
        List<Object[]> commandBlocks = new ArrayList<Object[]>();

        CommandDataBuilder builder = new CommandDataBuilder();

        // Reading tests
        List<String[]> data = csvReader.readAll();
        List<CommandData> command = new ArrayList<CommandData>();
        for (String[] testData : data) {
            if (testData.length <= 1) {
                if (command.size() > 0) {
                    commandBlocks.add(new Object[]{command});
                    command = new ArrayList<CommandData>();
                }
            } else {
                CommandData commandData = builder.build(testData);
                command.add(commandData);
            }
        }
        if (command.size() > 0) {
            commandBlocks.add(new Object[]{command});
        }
        return commandBlocks.iterator();
    }