Discord.js: Calling message.mentions on offline user results in the returned collection being empty

[matthewbetts96]

Tldr: Calling message.mentions on a user that is offline results in the returned collection being empty.

Code snippet:

const Discord = require('discord.js');
const bot = new Discord.Client();

bot.on('message', message => {
    if (message.content.startsWith("!")) {
        console.log(message.mentions.members);
    }
});

bot.login(TOKEN_HERE);

Repro steps:

User is online, call command "!test @testuser" returns following https://pastebin.com/U4UcHdAp, this is expected behaviour.

However, if the user then goes offline by closing discord or just appearing offline, then the returned collection is simply

Collection [Map] {}

Further details:

• discord.js version: 11.4.2
• Node.js version: 10.5.0
• Operating system: Windows 7
• Priority this issue should have – please be realistic and elaborate if possible:

• [ ] I have also tested the issue on latest master, commit hash:

[iCrawl]

Both are intended behavior.
mentions.members operates on cache, if you don't have the person in cache, they won't show up.

[matthewbetts96]

If it's intended behaviour then okay, there probably should be a note in the docs about it.

In my specific circumstance though, I need to check the permissions of the @'ed user through hasPermission, to do this I need a GuildMember which only message.mentions.members provides. I currently can't see a way around this.

[matthewbetts96]

Another user on the discord suggested this
"MessageMentions.users instead, which doesn't rely on cache. And u can use Guild.fetchMember(...) passing the User which will return a Promise that resolves into a GuildMember which u can call hasPermission on"

I'll close this issue, thanks for the response.