def test_multiple_repetition_operators():
    """
    Test using of multiple repetition operators.
    """
    grammar = """
    S: "2" b*[comma] c+ "3"?;

    terminals
    b: "b";
    c: "c";
    comma: ",";
    """

    g = Grammar.from_string(grammar)
    assert g.get_nonterminal('b_0_comma')
    assert g.get_nonterminal('c_1')

    p = Parser(g)

    input_str = '2 b, b  c 3'
    result = p.parse(input_str)
    assert result == ["2", ["b", "b"], ["c"], "3"]