From c412cd75213c4b683cad702a92e7386ef5b94ff7 Mon Sep 17 00:00:00 2001
From: "Matt (IPv4) Cowley" <me@mattcowley.co.uk>
Date: Sat, 17 Oct 2020 14:34:49 +0100
Subject: [PATCH] feat(Message): add messageEditHistoryMaxSize to limit stored
 msg edits (#4867)

---
 src/client/Client.js                |  7 +++++++
 src/client/actions/MessageUpdate.js |  4 ++--
 src/structures/Message.js           | 11 +++++++++--
 src/util/Constants.js               |  3 +++
 typings/index.d.ts                  |  3 ++-
 5 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/src/client/Client.js b/src/client/Client.js
index 44d187017..fd02197cd 100644
--- a/src/client/Client.js
+++ b/src/client/Client.js
@@ -432,6 +432,13 @@ class Client extends BaseClient {
     if (typeof options.messageSweepInterval !== 'number' || isNaN(options.messageSweepInterval)) {
       throw new TypeError('CLIENT_INVALID_OPTION', 'messageSweepInterval', 'a number');
     }
+    if (
+      typeof options.messageEditHistoryMaxSize !== 'number' ||
+      isNaN(options.messageEditHistoryMaxSize) ||
+      options.messageEditHistoryMaxSize < -1
+    ) {
+      throw new TypeError('CLIENT_INVALID_OPTION', 'messageEditHistoryMaxSize', 'a number greater than or equal to -1');
+    }
     if (typeof options.fetchAllMembers !== 'boolean') {
       throw new TypeError('CLIENT_INVALID_OPTION', 'fetchAllMembers', 'a boolean');
     }
diff --git a/src/client/actions/MessageUpdate.js b/src/client/actions/MessageUpdate.js
index 07e2aacb3..7667dea4b 100644
--- a/src/client/actions/MessageUpdate.js
+++ b/src/client/actions/MessageUpdate.js
@@ -9,9 +9,9 @@ class MessageUpdateAction extends Action {
       const { id, channel_id, guild_id, author, timestamp, type } = data;
       const message = this.getMessage({ id, channel_id, guild_id, author, timestamp, type }, channel);
       if (message) {
-        message.patch(data);
+        const old = message.patch(data);
         return {
-          old: message._edits[0],
+          old,
           updated: message,
         };
       }
diff --git a/src/structures/Message.js b/src/structures/Message.js
index 439eb4aaa..1b4302df0 100644
--- a/src/structures/Message.js
+++ b/src/structures/Message.js
@@ -235,13 +235,18 @@ class Message extends Base {
   }
 
   /**
-   * Updates the message.
+   * Updates the message and returns the old message.
    * @param {Object} data Raw Discord message update data
+   * @returns {Message}
    * @private
    */
   patch(data) {
     const clone = this._clone();
-    this._edits.unshift(clone);
+    const { messageEditHistoryMaxSize } = this.client.options;
+    if (messageEditHistoryMaxSize !== 0) {
+      const editsLimit = messageEditHistoryMaxSize === -1 ? Infinity : messageEditHistoryMaxSize;
+      if (this._edits.unshift(clone) > editsLimit) this._edits.pop();
+    }
 
     if ('edited_timestamp' in data) this.editedTimestamp = new Date(data.edited_timestamp).getTime();
     if ('content' in data) this.content = data.content;
@@ -268,6 +273,8 @@ class Message extends Base {
     );
 
     this.flags = new MessageFlags('flags' in data ? data.flags : 0).freeze();
+
+    return clone;
   }
 
   /**
diff --git a/src/util/Constants.js b/src/util/Constants.js
index 251267b9b..2d9ab42db 100644
--- a/src/util/Constants.js
+++ b/src/util/Constants.js
@@ -19,6 +19,8 @@ const browser = (exports.browser = typeof window !== 'undefined');
  * sweepable (in seconds, 0 for forever)
  * @property {number} [messageSweepInterval=0] How frequently to remove messages from the cache that are older than
  * the message cache lifetime (in seconds, 0 for never)
+ * @property {number} [messageEditHistoryMaxSize=-1] Maximum number of previous versions to hold for an edited message
+ * (-1 or Infinity for unlimited - don't do this without sweeping, otherwise memory usage may climb indefinitely.)
  * @property {boolean} [fetchAllMembers=false] Whether to cache all guild members and users upon startup, as well as
  * upon joining a guild (should be avoided whenever possible)
  * @property {DisableMentionType} [disableMentions='none'] Default value for {@link MessageOptions#disableMentions}
@@ -43,6 +45,7 @@ exports.DefaultOptions = {
   messageCacheMaxSize: 200,
   messageCacheLifetime: 0,
   messageSweepInterval: 0,
+  messageEditHistoryMaxSize: -1,
   fetchAllMembers: false,
   disableMentions: 'none',
   partials: [],
diff --git a/typings/index.d.ts b/typings/index.d.ts
index f9dadb217..fd21dc033 100644
--- a/typings/index.d.ts
+++ b/typings/index.d.ts
@@ -978,7 +978,7 @@ declare module 'discord.js' {
   export class Message extends Base {
     constructor(client: Client, data: object, channel: TextChannel | DMChannel | NewsChannel);
     private _edits: Message[];
-    private patch(data: object): void;
+    private patch(data: object): Message;
 
     public activity: MessageActivity | null;
     public application: ClientApplication | null;
@@ -2317,6 +2317,7 @@ declare module 'discord.js' {
     messageCacheMaxSize?: number;
     messageCacheLifetime?: number;
     messageSweepInterval?: number;
+    messageEditHistoryMaxSize?: number;
     fetchAllMembers?: boolean;
     disableMentions?: 'none' | 'all' | 'everyone';
     allowedMentions?: MessageMentionOptions;