feat(Collectors): make collectors auto-stop when relevant structures are deleted (#3632)

* Collectors: make Collectors automatically stop when Channel, Guild, or Message are deleted.

* fix potential error with DM collectors

* Message collectors dont have a `this.message` you dummy

* Fix(various): nitpicks, documentation, typings, and stray error

* Pleasing mr tslint

* fix: typings

* Grammatical fixes

Co-Authored-By: SpaceEEC <spaceeec@yahoo.com>

* Fixing the linting after space's suggestions

* docs(ReactionCollector): remove whitespace

Co-authored-by: SpaceEEC <spaceeec@yahoo.com>

src/structures/MessageCollector.js

@@ -11,6 +11,7 @@ const { Events } = require('../util/Constants');
 
 /**
  * Collects messages on a channel.
+ * Will automatically stop if the channel (`'channelDelete'`) or guild (`'guildDelete'`) are deleted.
  * @extends {Collector}
  */
 class MessageCollector extends Collector {
@@ -38,16 +39,22 @@ class MessageCollector extends Collector {
     const bulkDeleteListener = (messages => {
       for (const message of messages.values()) this.handleDispose(message);
     }).bind(this);
+    this._handleChannelDeletion = this._handleChannelDeletion.bind(this);
+    this._handleGuildDeletion = this._handleGuildDeletion.bind(this);
 
     if (this.client.getMaxListeners() !== 0) this.client.setMaxListeners(this.client.getMaxListeners() + 1);
     this.client.on(Events.MESSAGE_CREATE, this.handleCollect);
     this.client.on(Events.MESSAGE_DELETE, this.handleDispose);
     this.client.on(Events.MESSAGE_BULK_DELETE, bulkDeleteListener);
+    this.client.on(Events.CHANNEL_DELETE, this._handleChannelDeletion);
+    this.client.on(Events.GUILD_DELETE, this._handleGuildDeletion);
 
     this.once('end', () => {
       this.client.removeListener(Events.MESSAGE_CREATE, this.handleCollect);
       this.client.removeListener(Events.MESSAGE_DELETE, this.handleDispose);
       this.client.removeListener(Events.MESSAGE_BULK_DELETE, bulkDeleteListener);
+      this.client.removeListener(Events.CHANNEL_DELETE, this._handleChannelDeletion);
+      this.client.removeListener(Events.GUILD_DELETE, this._handleGuildDeletion);
       if (this.client.getMaxListeners() !== 0) this.client.setMaxListeners(this.client.getMaxListeners() - 1);
     });
   }
@@ -93,6 +100,30 @@ class MessageCollector extends Collector {
     if (this.options.maxProcessed && this.received === this.options.maxProcessed) return 'processedLimit';
     return null;
   }
+
+  /**
+   * Handles checking if the channel has been deleted, and if so, stops the collector with the reason 'channelDelete'.
+   * @private
+   * @param {GuildChannel} channel The channel that was deleted
+   * @returns {void}
+   */
+  _handleChannelDeletion(channel) {
+    if (channel.id === this.channel.id) {
+      this.stop('channelDelete');
+    }
+  }
+
+  /**
+   * Handles checking if the guild has been deleted, and if so, stops the collector with the reason 'guildDelete'.
+   * @private
+   * @param {Guild} guild The guild that was deleted
+   * @returns {void}
+   */
+  _handleGuildDeletion(guild) {
+    if (this.channel.guild && guild.id === this.channel.guild.id) {
+      this.stop('guildDelete');
+    }
+  }
 }
 
 module.exports = MessageCollector;

src/structures/ReactionCollector.js

@@ -13,6 +13,8 @@ const { Events } = require('../util/Constants');
 
 /**
  * Collects reactions on messages.
+ * Will automatically stop if the message (`'messageDelete'`),
+ * channel (`'channelDelete'`), or guild (`'guildDelete'`) are deleted.
  * @extends {Collector}
  */
 class ReactionCollector extends Collector {
@@ -43,16 +45,25 @@ class ReactionCollector extends Collector {
     this.total = 0;
 
     this.empty = this.empty.bind(this);
+    this._handleChannelDeletion = this._handleChannelDeletion.bind(this);
+    this._handleGuildDeletion = this._handleGuildDeletion.bind(this);
+    this._handleMessageDeletion = this._handleMessageDeletion.bind(this);
 
     if (this.client.getMaxListeners() !== 0) this.client.setMaxListeners(this.client.getMaxListeners() + 1);
     this.client.on(Events.MESSAGE_REACTION_ADD, this.handleCollect);
     this.client.on(Events.MESSAGE_REACTION_REMOVE, this.handleDispose);
     this.client.on(Events.MESSAGE_REACTION_REMOVE_ALL, this.empty);
+    this.client.on(Events.MESSAGE_DELETE, this._handleMessageDeletion);
+    this.client.on(Events.CHANNEL_DELETE, this._handleChannelDeletion);
+    this.client.on(Events.GUILD_DELETE, this._handleGuildDeletion);
 
     this.once('end', () => {
       this.client.removeListener(Events.MESSAGE_REACTION_ADD, this.handleCollect);
       this.client.removeListener(Events.MESSAGE_REACTION_REMOVE, this.handleDispose);
       this.client.removeListener(Events.MESSAGE_REACTION_REMOVE_ALL, this.empty);
+      this.client.removeListener(Events.MESSAGE_DELETE, this._handleMessageDeletion);
+      this.client.removeListener(Events.CHANNEL_DELETE, this._handleChannelDeletion);
+      this.client.removeListener(Events.GUILD_DELETE, this._handleGuildDeletion);
       if (this.client.getMaxListeners() !== 0) this.client.setMaxListeners(this.client.getMaxListeners() - 1);
     });
 
@@ -131,6 +142,42 @@ class ReactionCollector extends Collector {
     return null;
   }
 
+  /**
+   * Handles checking if the message has been deleted, and if so, stops the collector with the reason 'messageDelete'.
+   * @private
+   * @param {Message} message The message that was deleted
+   * @returns {void}
+   */
+  _handleMessageDeletion(message) {
+    if (message.id === this.message.id) {
+      this.stop('messageDelete');
+    }
+  }
+
+  /**
+   * Handles checking if the channel has been deleted, and if so, stops the collector with the reason 'channelDelete'.
+   * @private
+   * @param {GuildChannel} channel The channel that was deleted
+   * @returns {void}
+   */
+  _handleChannelDeletion(channel) {
+    if (channel.id === this.message.channel.id) {
+      this.stop('channelDelete');
+    }
+  }
+
+  /**
+   * Handles checking if the guild has been deleted, and if so, stops the collector with the reason 'guildDelete'.
+   * @private
+   * @param {Guild} guild The guild that was deleted
+   * @returns {void}
+   */
+  _handleGuildDeletion(guild) {
+    if (this.message.guild && guild.id === this.message.guild.id) {
+      this.stop('guildDelete');
+    }
+  }
+
   /**
    * Gets the collector key for a reaction.
    * @param {MessageReaction} reaction The message reaction to get the key for

typings/index.d.ts

@@ -1023,6 +1023,9 @@ declare module 'discord.js' {
 
 	export class MessageCollector extends Collector<Snowflake, Message> {
 		constructor(channel: TextChannel | DMChannel, filter: CollectorFilter, options?: MessageCollectorOptions);
+		private _handleChannelDeletion(channel: GuildChannel): void;
+		private _handleGuildDeletion(guild: Guild): void;
+
 		public channel: Channel;
 		public options: MessageCollectorOptions;
 		public received: number;
@@ -1153,6 +1156,10 @@ declare module 'discord.js' {
 
 	export class ReactionCollector extends Collector<Snowflake, MessageReaction> {
 		constructor(message: Message, filter: CollectorFilter, options?: ReactionCollectorOptions);
+		private _handleChannelDeletion(channel: GuildChannel): void;
+		private _handleGuildDeletion(guild: Guild): void;
+		private _handleMessageDeletion(message: Message): void;
+
 		public message: Message;
 		public options: ReactionCollectorOptions;
 		public total: number;