From c999eea323fd757b06e921e6d3f76b1baed8a4b8 Mon Sep 17 00:00:00 2001
From: devil-ira <justthecooldude@gmail.com>
Date: Fri, 5 Aug 2022 11:08:15 +0200
Subject: [PATCH] Add `AppTypeRegistry` `Resource` to `bevy_app`

---
 crates/bevy_app/src/app.rs             | 12 +++++++++---
 crates/bevy_ecs/src/reflect.rs         |  5 +----
 crates/bevy_scene/src/dynamic_scene.rs |  3 ++-
 crates/bevy_scene/src/scene_loader.rs  |  5 +++--
 crates/bevy_scene/src/scene_spawner.rs |  4 ++--
 5 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/crates/bevy_app/src/app.rs b/crates/bevy_app/src/app.rs
index 38b2edc2c14a9..483beb656d837 100644
--- a/crates/bevy_app/src/app.rs
+++ b/crates/bevy_app/src/app.rs
@@ -1,5 +1,6 @@
 use crate::{CoreStage, Plugin, PluginGroup, PluginGroupBuilder, StartupSchedule, StartupStage};
 pub use bevy_derive::AppLabel;
+use bevy_derive::{Deref, DerefMut};
 use bevy_ecs::{
     event::{Event, Events},
     prelude::{FromWorld, IntoExclusiveSystem},
@@ -22,6 +23,11 @@ bevy_utils::define_label!(
     AppLabelId,
 );
 
+/// The [`Resource`] that stores the [`App`]'s [`TypeRegistry`](bevy_reflect::TypeRegistry).
+#[cfg(feature = "bevy_reflect")]
+#[derive(Resource, Clone, Deref, DerefMut, Default)]
+pub struct AppTypeRegistry(pub bevy_reflect::TypeRegistryArc);
+
 #[allow(clippy::needless_doctest_main)]
 /// A container of app logic and data.
 ///
@@ -74,7 +80,7 @@ impl Default for App {
     fn default() -> Self {
         let mut app = App::empty();
         #[cfg(feature = "bevy_reflect")]
-        app.init_resource::<bevy_reflect::TypeRegistryArc>();
+        app.init_resource::<AppTypeRegistry>();
 
         app.add_default_stages()
             .add_event::<AppExit>()
@@ -878,7 +884,7 @@ impl App {
     #[cfg(feature = "bevy_reflect")]
     pub fn register_type<T: bevy_reflect::GetTypeRegistration>(&mut self) -> &mut Self {
         {
-            let registry = self.world.resource_mut::<bevy_reflect::TypeRegistryArc>();
+            let registry = self.world.resource_mut::<AppTypeRegistry>();
             registry.write().register::<T>();
         }
         self
@@ -911,7 +917,7 @@ impl App {
         &mut self,
     ) -> &mut Self {
         {
-            let registry = self.world.resource_mut::<bevy_reflect::TypeRegistryArc>();
+            let registry = self.world.resource_mut::<AppTypeRegistry>();
             registry.write().register_type_data::<T, D>();
         }
         self
diff --git a/crates/bevy_ecs/src/reflect.rs b/crates/bevy_ecs/src/reflect.rs
index ae1e970eda5e2..0b288b3aa7ac0 100644
--- a/crates/bevy_ecs/src/reflect.rs
+++ b/crates/bevy_ecs/src/reflect.rs
@@ -9,7 +9,7 @@ use crate::{
 };
 use bevy_reflect::{
     impl_from_reflect_value, impl_reflect_value, FromType, Reflect, ReflectDeserialize,
-    ReflectSerialize, TypeRegistryArc,
+    ReflectSerialize,
 };
 
 /// A struct used to operate on reflected [`Component`] of a type.
@@ -316,6 +316,3 @@ impl<C: Component + MapEntities> FromType<C> for ReflectMapEntities {
         }
     }
 }
-
-// We cannot implement this in bevy_reflect, or we would create a cyclic dependendency
-impl Resource for TypeRegistryArc {}
diff --git a/crates/bevy_scene/src/dynamic_scene.rs b/crates/bevy_scene/src/dynamic_scene.rs
index 7328f5f366267..1de7202bfab4e 100644
--- a/crates/bevy_scene/src/dynamic_scene.rs
+++ b/crates/bevy_scene/src/dynamic_scene.rs
@@ -1,5 +1,6 @@
 use crate::{serde::SceneSerializer, Scene, SceneSpawnError};
 use anyhow::Result;
+use bevy_app::AppTypeRegistry;
 use bevy_ecs::{
     entity::EntityMap,
     reflect::{ReflectComponent, ReflectMapEntities},
@@ -84,7 +85,7 @@ impl DynamicScene {
         world: &mut World,
         entity_map: &mut EntityMap,
     ) -> Result<(), SceneSpawnError> {
-        let registry = world.resource::<TypeRegistryArc>().clone();
+        let registry = world.resource::<AppTypeRegistry>().clone();
         let type_registry = registry.read();
 
         for scene_entity in &self.entities {
diff --git a/crates/bevy_scene/src/scene_loader.rs b/crates/bevy_scene/src/scene_loader.rs
index 2a44af0cf51ca..e13b2541eeb13 100644
--- a/crates/bevy_scene/src/scene_loader.rs
+++ b/crates/bevy_scene/src/scene_loader.rs
@@ -1,5 +1,6 @@
 use crate::serde::SceneDeserializer;
 use anyhow::Result;
+use bevy_app::AppTypeRegistry;
 use bevy_asset::{AssetLoader, LoadContext, LoadedAsset};
 use bevy_ecs::world::{FromWorld, World};
 use bevy_reflect::TypeRegistryArc;
@@ -13,9 +14,9 @@ pub struct SceneLoader {
 
 impl FromWorld for SceneLoader {
     fn from_world(world: &mut World) -> Self {
-        let type_registry = world.resource::<TypeRegistryArc>();
+        let type_registry = world.resource::<AppTypeRegistry>();
         SceneLoader {
-            type_registry: (*type_registry).clone(),
+            type_registry: type_registry.0.clone(),
         }
     }
 }
diff --git a/crates/bevy_scene/src/scene_spawner.rs b/crates/bevy_scene/src/scene_spawner.rs
index b57324fc57528..d9bfcb213687e 100644
--- a/crates/bevy_scene/src/scene_spawner.rs
+++ b/crates/bevy_scene/src/scene_spawner.rs
@@ -1,4 +1,5 @@
 use crate::{DynamicScene, Scene};
+use bevy_app::AppTypeRegistry;
 use bevy_asset::{AssetEvent, Assets, Handle};
 use bevy_ecs::{
     entity::{Entity, EntityMap},
@@ -8,7 +9,6 @@ use bevy_ecs::{
     world::{Mut, World},
 };
 use bevy_hierarchy::{AddChild, Parent};
-use bevy_reflect::TypeRegistryArc;
 use bevy_utils::{tracing::error, HashMap};
 use thiserror::Error;
 use uuid::Uuid;
@@ -164,7 +164,7 @@ impl SceneSpawner {
         let mut instance_info = InstanceInfo {
             entity_map: EntityMap::default(),
         };
-        let type_registry = world.resource::<TypeRegistryArc>().clone();
+        let type_registry = world.resource::<AppTypeRegistry>().clone();
         let type_registry = type_registry.read();
         world.resource_scope(|world, scenes: Mut<Assets<Scene>>| {
             let scene =