Method unsubscribe

packages/client/lib/client/pub-sub.ts:224–303

(
    type: PubSubType,
    channels?: string | Array<string>,
    listener?: PubSubListener<T>,
    returnBuffers?: T
  )

  }

  unsubscribe<T extends boolean>(
    type: PubSubType,
    channels?: string | Array<string>,
    listener?: PubSubListener<T>,
    returnBuffers?: T
  ) {
    const listeners = this.listeners[type];
    if (!channels) {
      return this.#unsubscribeCommand(
        [COMMANDS[type].unsubscribe],
        // cannot use `this.#subscribed` because there might be some `SUBSCRIBE` commands in the queue
        // cannot use `this.#subscribed + this.#subscribing` because some `SUBSCRIBE` commands might fail
        NaN,
        () => listeners.clear()
      );
    }

    const channelsArray = PubSub.#channelsArray(channels);
    if (!listener) {
      return this.#unsubscribeCommand(
        [COMMANDS[type].unsubscribe, ...channelsArray],
        channelsArray.length,
        () => {
          for (const channel of channelsArray) {
            listeners.delete(channel);
          }
        }
      );
    }

    const args: Array<RedisArgument> = [COMMANDS[type].unsubscribe];
    for (const channel of channelsArray) {
      const sets = listeners.get(channel);
      if (sets) {
        let current,
          other;
        if (returnBuffers) {
          current = sets.buffers;
          other = sets.strings;
        } else {
          current = sets.strings;
          other = sets.buffers;
        }

        const currentSize = current.has(listener) ? current.size - 1 : current.size;
        if (currentSize !== 0 || other.size !== 0) continue;
        sets.unsubscribing = true;
      }

      args.push(channel);
    }

    if (args.length === 1) {
      // all channels has other listeners,
      // delete the listeners without issuing a command
      for (const channel of channelsArray) {
        PubSub.#listenersSet(
          listeners.get(channel)!,