fix(InteractionResponses): check if ephemeral message flag is used (#…

…10021)

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

@@ -3,6 +3,7 @@
 const { isJSONEncodable } = require('@discordjs/util');
 const { InteractionResponseType, MessageFlags, Routes, InteractionType } = require('discord-api-types/v10');
 const { DiscordjsError, ErrorCodes } = require('../../errors');
+const MessageFlagsBitField = require('../../util/MessageFlagsBitField');
 const InteractionCollector = require('../InteractionCollector');
 const InteractionResponse = require('../InteractionResponse');
 const MessagePayload = require('../MessagePayload');
@@ -100,14 +101,15 @@ class InteractionResponses {
    */
   async reply(options) {
     if (this.deferred || this.replied) throw new DiscordjsError(ErrorCodes.InteractionAlreadyReplied);
-    this.ephemeral = options.ephemeral ?? false;
 
     let messagePayload;
     if (options instanceof MessagePayload) messagePayload = options;
     else messagePayload = MessagePayload.create(this, options);
 
     const { body: data, files } = await messagePayload.resolveBody().resolveFiles();
 
+    this.ephemeral = new MessageFlagsBitField(data.flags).has(MessageFlags.Ephemeral);
+
     await this.client.rest.post(Routes.interactionCallback(this.id, this.token), {
       body: {
         type: InteractionResponseType.ChannelMessageWithSource,