How to use the colin.utils.cmd_tools.retry function in colin

    @retry(5, 0)
    def sleep_like_a_baby():
        global COUNTER
        if COUNTER < 3:
            COUNTER += 1
            raise Exception("sleeping")
        return []

    @retry(5, -1)
    def fail_negative_sleep():
        raise_exception()

def test_wrong_parameter():
    with pytest.raises(ValueError) as ex:
        retry(-1, 1)
    assert str(ex.value) == 'retry_count have to be positive'

    with pytest.raises(ValueError) as ex:
        retry(0, 1)
    assert str(ex.value) == 'retry_count have to be positive'

    @retry(5, -1)
    def fail_negative_sleep():
        raise_exception()

    with pytest.raises(ValueError) as ex:
        fail_negative_sleep()
    assert str(ex.value) == 'sleep length must be non-negative'

    @retry(5, 0)
    def always_success():
        global COUNTER
        COUNTER = COUNTER + 1

        return 42

    @retry(5, 0)
    def always_raise_exception():
        raise_exception()

    @retry(4, .5)
    def fail_and_sleep():
        raise_exception()

def test_wrong_parameter():
    with pytest.raises(ValueError) as ex:
        retry(-1, 1)
    assert str(ex.value) == 'retry_count have to be positive'

    with pytest.raises(ValueError) as ex:
        retry(0, 1)
    assert str(ex.value) == 'retry_count have to be positive'

    @retry(5, -1)
    def fail_negative_sleep():
        raise_exception()

    with pytest.raises(ValueError) as ex:
        fail_negative_sleep()
    assert str(ex.value) == 'sleep length must be non-negative'