feat: message forwards (#10733)

* feat: message forwards

* fix: spelling

* feat: add guildId option for forward

* refactor: type

* refactor: do not use ID suffix for resolvables

* Update TextBasedChannel.js

---------

Co-authored-by: Jiralite <33201955+Jiralite@users.noreply.github.com>

packages/discord.js/src/structures/Message.js

@@ -9,6 +9,7 @@ const {
   MessageType,
   MessageFlags,
   PermissionFlagsBits,
+  MessageReferenceType,
 } = require('discord-api-types/v10');
 const Attachment = require('./Attachment');
 const Base = require('./Base');
@@ -704,7 +705,11 @@ class Message extends Base {
    * @readonly
    */
   get editable() {
-    const precheck = Boolean(this.author.id === this.client.user.id && (!this.guild || this.channel?.viewable));
+    const precheck = Boolean(
+      this.author.id === this.client.user.id &&
+        (!this.guild || this.channel?.viewable) &&
+        this.reference?.type !== MessageReferenceType.Forward,
+    );
 
     // Regardless of permissions thread messages cannot be edited if
     // the thread is archived or the thread is locked and the bot does not have permission to manage threads.
@@ -956,6 +961,24 @@ class Message extends Base {
     return this.channel.send(data);
   }
 
+  /**
+   * Forwards this message
+   *
+   * @param {TextBasedChannelResolvable} channel The channel to forward this message to.
+   * @returns {Promise<Message>}
+   */
+  forward(channel) {
+    const resolvedChannel = this.client.channels.resolve(channel);
+    if (!resolvedChannel) throw new DiscordjsError(ErrorCodes.InvalidType, 'channel', 'TextBasedChannelResolvable');
+    return resolvedChannel.send({
+      forward: {
+        message: this.id,
+        channel: this.channelId,
+        guild: this.guildId,
+      },
+    });
+  }
+
   /**
    * Options for starting a thread on a message.
    * @typedef {Object} StartThreadOptions

packages/discord.js/src/structures/MessagePayload.js

@@ -3,7 +3,7 @@
 const { Buffer } = require('node:buffer');
 const { lazy, isJSONEncodable } = require('@discordjs/util');
 const { DiscordSnowflake } = require('@sapphire/snowflake');
-const { MessageFlags } = require('discord-api-types/v10');
+const { MessageFlags, MessageReferenceType } = require('discord-api-types/v10');
 const ActionRowBuilder = require('./ActionRowBuilder');
 const { DiscordjsError, DiscordjsRangeError, ErrorCodes } = require('../errors');
 const { resolveFile } = require('../util/DataResolver');
@@ -199,6 +199,22 @@ class MessagePayload {
       }
     }
 
+    if (typeof this.options.forward === 'object') {
+      const reference = this.options.forward.message;
+      const channel_id = reference.channelId ?? this.target.client.channels.resolveId(this.options.forward.channel);
+      const guild_id = reference.guildId ?? this.target.client.guilds.resolveId(this.options.forward.guild);
+      const message_id = this.target.messages.resolveId(reference);
+      if (message_id) {
+        if (!channel_id) throw new DiscordjsError(ErrorCodes.InvalidType, 'channelId', 'TextBasedChannelResolvable');
+        message_reference = {
+          type: MessageReferenceType.Forward,
+          message_id,
+          channel_id,
+          guild_id: guild_id ?? undefined,
+        };
+      }
+    }
+
     const attachments = this.options.files?.map((file, index) => ({
       id: index.toString(),
       description: file.description,

packages/discord.js/src/structures/interfaces/TextBasedChannel.js

@@ -110,10 +110,18 @@ class TextBasedChannel {
    * <info>Only `MessageFlags.SuppressEmbeds` and `MessageFlags.SuppressNotifications` can be set.</info>
    */
 
+  /**
+   * @typedef {Object} ForwardOptions
+   * @property {MessageResolvable} message The originating message
+   * @property {TextBasedChannelResolvable} [channel] The channel of the originating message
+   * @property {GuildResolvable} [guild] The guild of the originating message
+   */
+
   /**
    * The options for sending a message.
    * @typedef {BaseMessageCreateOptions} MessageCreateOptions
    * @property {ReplyOptions} [reply] The options for replying to a message
+   * @property {ForwardOptions} [forward] The options for forwarding a message
    */
 
   /**

packages/discord.js/typings/index.d.ts

@@ -2310,6 +2310,7 @@ export class Message<InGuild extends boolean = boolean> extends Base {
   public reply(
     options: string | MessagePayload | MessageReplyOptions,
   ): Promise<OmitPartialGroupDMChannel<Message<InGuild>>>;
+  public forward(channel: Exclude<TextBasedChannelResolvable, PartialGroupDMChannel>): Promise<Message>;
   public resolveComponent(customId: string): MessageActionRowComponent | null;
   public startThread(options: StartThreadOptions): Promise<PublicThreadChannel<false>>;
   public suppressEmbeds(suppress?: boolean): Promise<OmitPartialGroupDMChannel<Message<InGuild>>>;
@@ -6759,6 +6760,7 @@ export interface MessageCreateOptions extends BaseMessageOptionsWithPoll {
   nonce?: string | number;
   enforceNonce?: boolean;
   reply?: ReplyOptions;
+  forward?: ForwardOptions;
   stickers?: readonly StickerResolvable[];
   flags?:
     | BitFieldResolvable<
@@ -7011,7 +7013,21 @@ export interface ReplyOptions {
   failIfNotExists?: boolean;
 }
 
-export interface MessageReplyOptions extends Omit<MessageCreateOptions, 'reply'> {
+export interface BaseForwardOptions {
+  message: MessageResolvable;
+  channel?: Exclude<TextBasedChannelResolvable, PartialGroupDMChannel>;
+  guild?: GuildResolvable;
+}
+
+export type ForwardOptionsWithMandatoryChannel = BaseForwardOptions & Required<Pick<BaseForwardOptions, 'channel'>>;
+
+export interface ForwardOptionsWithOptionalChannel extends BaseForwardOptions {
+  message: Exclude<MessageResolvable, Snowflake>;
+}
+
+export type ForwardOptions = ForwardOptionsWithMandatoryChannel | ForwardOptionsWithOptionalChannel;
+
+export interface MessageReplyOptions extends Omit<MessageCreateOptions, 'reply' | 'forward'> {
   failIfNotExists?: boolean;
 }
 
@@ -7290,7 +7306,8 @@ export interface WebhookFetchMessageOptions {
   threadId?: Snowflake;
 }
 
-export interface WebhookMessageCreateOptions extends Omit<MessageCreateOptions, 'nonce' | 'reply' | 'stickers'> {
+export interface WebhookMessageCreateOptions
+  extends Omit<MessageCreateOptions, 'nonce' | 'reply' | 'stickers' | 'forward'> {
   username?: string;
   avatarURL?: string;
   threadId?: Snowflake;