Add guild permissions check

[jamesbt365]

Saves bot users doing this themselves if they prefer to have commands that follow the guild permissions instead of the current channel permissions, seems like something that should be built into the framework.

[TaromaruYuki]

No idea if you specifically need this now, but for anyone else figuring this out I threw something together. It's bad, but the type checker is happy. I'm skipping a lot of checking for the example too, so don't forget that. Hope this helps someone.

let guild = ctx.guild().unwrap().to_owned();
let member = ctx.http().get_member(guild.id, ctx.author().id).await.unwrap();

if let Some(role) = guild.member_highest_role(&member) {
    if role.has_permissions(Permissions::MODERATE_MEMBERS, false) {
        // Code here
    }
} else {
    // No role, default action
}

I found that a lot of the functions like .guild() and .guild_member() from ctx made the type checker angry about futures and threads. So this is my workaround.

[jamesbt365]

@TaromaruYuki that is really bad bad performance wise, is a massive crash risk, doesn't even cover cases of other roles having permissions and doesn't leverage the data you already have.

This is exactly the reason this needs to have something built-in to poise, but I'd prefer you didn't clog this issue with incorrect code.

[TaromaruYuki]

i was basing that code off some other code that was completely irrelevant. i make trash, optimize, and learn, its my autistic learning process.

so there is serenity::Member::permissions, but it's deprecated and may be removed anytime. you'll need to use Guild::user_permissions_in to check for a specific channel.

the only other way would be to get all the roles of the member and combine all the permissions of each one with bit wise or. this can be inefficient though.