feat(InlineReplies): provide support for inline-replying to messages

src/structures/APIMessage.js

@@ -198,6 +198,14 @@ class APIMessage {
       }
     }
 
+    let message_reference;
+    if (this.options.messageReference) {
+      message_reference = {
+        message_id: this.target.messages.resolveID(this.options.messageReference),
+        channel_id: this.target.id,
+      };
+    }
+
     this.data = {
       content,
       tts,
@@ -208,6 +216,7 @@ class APIMessage {
       avatar_url: avatarURL,
       allowed_mentions: typeof content === 'undefined' ? undefined : allowedMentions,
       flags,
+      message_reference,
     };
     return this;
   }

src/structures/interfaces/TextBasedChannel.js

@@ -66,6 +66,7 @@ class TextBasedChannel {
    * @property {boolean|SplitOptions} [split=false] Whether or not the message should be split into multiple messages if
    * it exceeds the character limit. If an object is provided, these are the options for splitting the message
    * @property {UserResolvable} [reply] User to reply to (prefixes the message with a mention, except in DMs)
+   * @property {MessageResolvable} [messageReference] The message to inline-reply to (must be in the same channel)
    */
 
   /**

typings/index.d.ts

@@ -2831,7 +2831,7 @@ declare module 'discord.js' {
     code?: string | boolean;
     split?: boolean | SplitOptions;
     reply?: UserResolvable;
-    messageReference?: MessageResolvable | MessageReplyReference;
+    messageReference?: MessageResolvable;
   }
 
   type MessageReactionResolvable = MessageReaction | Snowflake;
@@ -2842,11 +2842,6 @@ declare module 'discord.js' {
     messageID: string | null;
   }
 
-  interface MessageReplyReference {
-    channelID: string;
-    messageID: string;
-  }
-
   type MessageResolvable = Message | Snowflake;
 
   type MessageTarget = TextChannel | NewsChannel | DMChannel | User | GuildMember | Webhook | WebhookClient;