public Hub(HubState state, IUserTopic topic, ITimeProvider timeProvider)
{
_state = state ?? throw new ArgumentNullException(nameof(state));
_topic = topic ?? throw new ArgumentNullException(nameof(topic));
_timeProvider = timeProvider ?? throw new ArgumentNullException(nameof(timeProvider));
}
public Hub(HubState state, IUserTopic topic)
: this(state, topic, new SystemTimeProvider())
{
}
