auto_register.rs

use bevy::app::prelude::*;
use dyn_clone::DynClone;

pub trait AppExt {
    fn add_all_plugins(&mut self);
}

impl AppExt for App {
    fn add_all_plugins(&mut self) {
        for plugin in inventory::iter::<AutoPlugin> {
            self.add_boxed_plugin(plugin.0.clone_box().upcast_plugin()).unwrap();
        }
    }
}

pub trait DynPlugin: Plugin + DynClone {
    fn clone_box(&self) -> Box<dyn DynPlugin>;
    fn upcast_plugin(self: Box<Self>) -> Box<dyn Plugin>;
}

impl<T: Plugin + Clone> DynPlugin for T {
    fn clone_box(&self) -> Box<dyn DynPlugin> {
        dyn_clone::clone_box(&*self)
    }

    fn upcast_plugin(self: Box<Self>) -> Box<dyn Plugin> {
        self
    }
}

pub struct AutoPlugin(Box<dyn DynPlugin>);

impl AutoPlugin {
    pub fn from_plugin<P: Plugin + Clone>(plugin: P) -> Self {
        AutoPlugin(Box::new(plugin))
    }
}

inventory::collect!(AutoPlugin);