Bug: TypeError: fn is not a function

Issue description

this code is executed on messageCreate. I was unable to figure out when exactly the program terminates but this is the error stack:

C:\code\js\kciw-remake\node_modules\@discordjs\collection\dist\index.js:191
            return fn(value, key, this);
                   ^

TypeError: fn is not a function
    at C:\code\js\kciw-remake\node_modules\@discordjs\collection\dist\index.js:191:20
    at Function.from (<anonymous>)
    at Map.map (C:\code\js\kciw-remake\node_modules\@discordjs\collection\dist\index.js:189:22)
    at Object.execute (C:\code\js\kciw-remake\events\messageCreate.js:18:40)
    at Client.<anonymous> (C:\code\js\kciw-remake\index.js:42:45)
    at Client.emit (node:events:394:28)
    at MessageCreateAction.handle (C:\code\js\kciw-remake\node_modules\discord.js\src\client\actions\MessageCreate.js:23:14)
    at Object.module.exports [as MESSAGE_CREATE] (C:\code\js\kciw-remake\node_modules\discord.js\src\client\websocket\handlers\MESSAGE_CREATE.js:4:32)
    at WebSocketManager.handlePacket (C:\code\js\kciw-remake\node_modules\discord.js\src\client\websocket\WebSocketManager.js:350:31)
    at WebSocketShard.onPacket (C:\code\js\kciw-remake\node_modules\discord.js\src\client\websocket\WebSocketShard.js:443:22)

the code at at Object.execute (C:\code\js\kciw-remake\events\messageCreate.js:18:40) is this: const afks = message.mentions.users.map();

the code at at Client.<anonymous> (C:\code\js\kciw-remake\index.js:42:45) is this: client.on(event.name, (...args) => event.execute(...args, client)); <-- this is executing normally so the problem isn't there

Codesample

const Discord = require('discord.js');
const db = require('quick.db');

module.exports = {
name: 'messageCreate',
async execute(message, client) {
if(message.mentions.users.map(i => i.id).length > 0) {
            const afks = message.mentions.users.map();
            const embedList = [];
            const afkList = [];

            afks.forEach(i => {
                afkList.push(db.get(`afk.${i.id}`));
            });

            afks.forEach(afkFun);

            function afkFun(value, index) {
                if(Object.keys(db.get('afk').includes(value.id))) {
                    embedList.push(
                        new Discord.MessageEmbed().setTitle(`${value.username} is AFK!`)
                            .setDescription(
                                `Reason: ${afkList[index].reason}\n<t:${Math.round(afkList[index].time / 1000)}:R>`,
                            )
                            .setColor(color.red),
                    );
                }
                db.has(`afk.${value.id}.pings`)
                    ? db.push(`afk.${value.id}.pings`, {
                        time: Date.now(),
                        user: message.author.id,
                        link: message.url,
                        channel: message.channel.id,
                    })
                    : db.set(`afk.${value.id}.pings`, {
                        time: Date.now(),
                        user: message.author.id,
                        link: message.url,
                        channel: message.channel.id,
                    });

                message.channel.send({ embeds: embedList });
            }}
            const pingEmbed = new Discord.MessageEmbed().setDescription(
                db.has(`afk.${message.author.id}.pings`)
                    ? db
                        .get(`afk.${message.author.id}.pings`)
                        .map(
                            i =>
                                `[<t:${Math.round(i.time / 1000)}:R>](${i.link}) <@${
                                    i.user
                                }> - <#${i.channel}>`,
                        )
                        .join('\n')
                    : 'You have no pings!',
            );
            message.channel.send({
                embeds: [mainEmbed, pingEmbed],
            });
            db.delete(`afk.${message.author.id}`);
        }
},
};

discord.js version

13.1.0

Node.js version

16.9.1

Operating system

Windows

Priority this issue should have

Medium (should be fixed soon)

Which partials do you have configured?

No Partials

Which gateway intents are you subscribing to?

GUILDS, GUILD_MEMBERS, GUILD_WEBHOOKS, GUILD_PRESENCES, GUILD_MESSAGES, DIRECT_MESSAGES

I have tested this issue on a development release

discord.js@13.2.0-dev.1632312194.92f6471

discordjs / discord.js