@CheckForNull
  static String checkEventDescription(@Nullable String description) {
    if (description == null) {
      return null;
    }
    checkArgument(description.length() <= MAX_DESCRIPTION_LENGTH, "Event description length (%s) is longer than the maximum authorized (%s). '%s' was provided.",
      description.length(), MAX_DESCRIPTION_LENGTH, description);
    return description;
  }
@Test
  void fail_if_description_longer_than_4000() {
    assertThatThrownBy(() -> EventValidator.checkEventDescription(repeat("a", 4000 + 1)))
      .isInstanceOf(IllegalArgumentException.class)
      .hasMessageContaining("Event description length (4001) is longer than the maximum authorized (4000).");
  }