fix: Convert lastMessage to getters (#2384)

* convert lastMessage to getters

* fix bug in pr

* requested changes

src/client/actions/MessageCreate.js

@@ -12,14 +12,13 @@ class MessageCreateAction extends Action {
       const user = message.author;
       const member = channel.guild ? channel.guild.member(user) : null;
       channel.lastMessageID = data.id;
-      channel.lastMessage = message;
       if (user) {
         user.lastMessageID = data.id;
-        user.lastMessage = message;
+        user.lastMessageChannelID = channel.id;
       }
       if (member) {
         member.lastMessageID = data.id;
-        member.lastMessage = message;
+        member.lastMessageChannelID = channel.id;
       }
 
       client.emit(Events.MESSAGE_CREATE, message);

src/structures/DMChannel.js

@@ -44,6 +44,7 @@ class DMChannel extends Channel {
 
   // These are here only for documentation purposes - they are implemented by TextBasedChannel
   /* eslint-disable no-empty-function */
+  get lastMessage() {}
   send() {}
   search() {}
   startTyping() {}

src/structures/GroupDMChannel.js

@@ -220,6 +220,7 @@ class GroupDMChannel extends Channel {
 
   // These are here only for documentation purposes - they are implemented by TextBasedChannel
   /* eslint-disable no-empty-function */
+  get lastMessage() {}
   send() {}
   search() {}
   startTyping() {}

src/structures/GuildMember.js

@@ -43,10 +43,10 @@ class GuildMember extends Base {
     this.lastMessageID = null;
 
     /**
-     * The Message object of the last message sent by the member in their guild, if one was sent
+     * The ID of the channel for the last message sent by the member in their guild, if one was sent
-     * @type {?Message}
+     * @type {?Snowflake}
      */
-    this.lastMessage = null;
+    this.lastMessageChannelID = null;
   }
 
   _patch(data) {
@@ -81,6 +81,16 @@ class GuildMember extends Base {
     return clone;
   }
 
+  /**
+   * The Message object of the last message sent by the member in their guild, if one was sent
+   * @type {?Message}
+   * @readonly
+   */
+  get lastMessage() {
+    const channel = this.guild.channels.get(this.lastMessageChannelID);
+    return (channel && channel.messages.get(this.lastMessageID)) || null;
+  }
+
   get voiceState() {
     return this._frozenVoiceState || this.guild.voiceStates.get(this.id) || {};
   }

src/structures/TextChannel.js

@@ -96,6 +96,7 @@ class TextChannel extends GuildChannel {
 
   // These are here only for documentation purposes - they are implemented by TextBasedChannel
   /* eslint-disable no-empty-function */
+  get lastMessage() {}
   send() {}
   search() {}
   startTyping() {}

src/structures/User.js

@@ -59,10 +59,10 @@ class User extends Base {
     this.lastMessageID = null;
 
     /**
-     * The Message object of the last message sent by the user, if one was sent
+     * The ID of the channel for the last message sent by the user, if one was sent
-     * @type {?Message}
+     * @type {?Snowflake}
      */
-    this.lastMessage = null;
+    this.lastMessageChannelID = null;
   }
 
   /**
@@ -83,6 +83,16 @@ class User extends Base {
     return new Date(this.createdTimestamp);
   }
 
+  /**
+   * The Message object of the last message sent by the user, if one was sent
+   * @type {?Message}
+   * @readonly
+   */
+  get lastMessage() {
+    const channel = this.client.channels.get(this.lastMessageChannelID);
+    return (channel && channel.messages.get(this.lastMessageID)) || null;
+  }
+
   /**
    * The presence of this user
    * @type {Presence}

src/structures/interfaces/TextBasedChannel.js

@@ -21,12 +21,15 @@ class TextBasedChannel {
      * @type {?Snowflake}
      */
     this.lastMessageID = null;
+  }
 
-    /**
+  /**
-     * The Message object of the last message in the channel, if one was sent
+   * The Message object of the last message in the channel, if one was sent
-     * @type {?Message}
+   * @type {?Message}
-     */
+   * @readonly
-    this.lastMessage = null;
+   */
+  get lastMessage() {
+    return this.messages.get(this.lastMessageID) || null;
   }
 
   /**
@@ -334,6 +337,7 @@ class TextBasedChannel {
     if (full) {
       props.push(
         'acknowledge',
+        'lastMessage',
         'search',
         'bulkDelete',
         'startTyping',