fix: Shared references causing auto thread to be added to new channels

[Simplyalex99]

description: This pull-request fixes #461 . The issue had to do with the addHandler function using mutated arrays or references rather than creating a new one resulting in an unexpected behaviour of the auto thread handler being added to new channels. In other words, adding a handler to one channel might affect other channels that share the same reference.

steps to reproduce

1. Create a new channel in React Test Server and add it to channels constant ( using the testing-bug-thread channel)

const LOCAL_CHANNELS: Record<keyof typeof PRODUCTION_CHANNELS, string> = {
   newChannel: "1383553919950520450"
  helpReact: "926931785219207301",
helpJs:"950790460857794620"
 ...
};

const PRODUCTION_CHANNELS = {
  newChannel: "1383553919950520450"
  helpReact: "103696749012467712",
 helpJs:"950790460857794620"
  ...
};

2. Create a new empty handler

import type { ChannelHandlers } from "../types/index.d.ts";
import { EmbedType } from "discord.js";
import { EMBED_COLOR } from "./commands.js";

export const messageScanner: ChannelHandlers = {
  handleMessage: async ({ msg }) => {
    if (msg.author.bot) return;

    const warningMsg = `Testing message`;
    await msg.reply({
      embeds: [
        {
          title: "Oops! Wrong Channel, Maybe?",
          type: EmbedType.Rich,
          description: warningMsg,
          color: EMBED_COLOR,
        },
      ],
    });


  },
};

3. Add the new handler with the new channel ID and a shared channel auto thread ID like helpJs:

addHandler([CHANNELS.newChannel,CHANNELS.helpJs>], newHandler);

4. Type in the testing-bug-thread channel , and a thread will be created:

Actual Behaviour

New channels added will result in having shared handlers.

The expected behaviour

Any new channels added should not have other handlers added to them unless specified.

Solution

The solution now replaces .push and declaration with the spread operator.

// original
if (existingHandlers) {
      existingHandlers.push(...handlers);
    } else {
      channelHandlersById[channelId] = handlers;
    }

// solution
 if (existingHandlers) {
      // Create a new array to avoid mutating the existing one
      channelHandlersById[channelId] = [...existingHandlers, ...handlers];
    } else {
      channelHandlersById[channelId] = [...handlers];
    }