From db0f44b5863ed70ee12214c0fa9b9b6b0f3d0e8e Mon Sep 17 00:00:00 2001
From: Ellen <supbscripter@gmail.com>
Date: Fri, 4 Mar 2022 01:56:10 +0000
Subject: [PATCH] >:(

---
 crates/bevy_ecs/src/entity/mod.rs |  6 +++++-
 crates/bevy_ecs/src/world/mod.rs  | 15 +++++++++------
 crates/bevy_render/src/lib.rs     |  4 ++--
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/crates/bevy_ecs/src/entity/mod.rs b/crates/bevy_ecs/src/entity/mod.rs
index cedfdbafca203c..86a99132f197e9 100644
--- a/crates/bevy_ecs/src/entity/mod.rs
+++ b/crates/bevy_ecs/src/entity/mod.rs
@@ -199,7 +199,7 @@ impl<'a> core::iter::ExactSizeIterator for ReserveEntitiesIterator<'a> {}
 
 #[derive(Debug, Default)]
 pub struct Entities {
-    pub meta: Vec<EntityMeta>,
+    pub(crate) meta: Vec<EntityMeta>,
 
     /// The `pending` and `free_cursor` fields describe three sets of Entity IDs
     /// that have been freed or are in the process of being allocated:
@@ -243,6 +243,10 @@ pub struct Entities {
 }
 
 impl Entities {
+    pub fn meta_len(&self) -> usize {
+        self.meta.len()
+    }
+
     /// Reserve entity IDs concurrently.
     ///
     /// Storage for entity generation and location is lazily allocated by calling `flush`.
diff --git a/crates/bevy_ecs/src/world/mod.rs b/crates/bevy_ecs/src/world/mod.rs
index 22add5b970365a..edf627678d536d 100644
--- a/crates/bevy_ecs/src/world/mod.rs
+++ b/crates/bevy_ecs/src/world/mod.rs
@@ -134,18 +134,21 @@ impl World {
         &self.entities
     }
 
-    /// Retrieves this world's [Entities] collection mutably
-    #[inline]
-    pub fn entities_mut(&mut self) -> &mut Entities {
-        &mut self.entities
-    }
-
     /// Retrieves this world's [Archetypes] collection
     #[inline]
     pub fn archetypes(&self) -> &Archetypes {
         &self.archetypes
     }
 
+    /// Retrieves this world's [Entities] collection mutably
+    ///
+    /// # Safety
+    /// No funny business
+    #[inline]
+    pub unsafe fn entities_mut(&mut self) -> &mut Entities {
+        &mut self.entities
+    }
+
     /// Retrieves this world's [Components] collection
     #[inline]
     pub fn components(&self) -> &Components {
diff --git a/crates/bevy_render/src/lib.rs b/crates/bevy_render/src/lib.rs
index 36f4cbc2925000..7713162f635f71 100644
--- a/crates/bevy_render/src/lib.rs
+++ b/crates/bevy_render/src/lib.rs
@@ -189,7 +189,7 @@ impl Plugin for RenderPlugin {
 
                     // reserve all existing app entities for use in render_app
                     // they can only be spawned using `get_or_spawn()`
-                    let meta_len = app_world.entities().meta.len();
+                    let meta_len = app_world.entities().meta_len();
                     render_app
                         .world
                         .entities()
@@ -198,7 +198,7 @@ impl Plugin for RenderPlugin {
                     // flushing as "invalid" ensures that app world entities aren't added as "empty archetype" entities by default
                     // these entities cannot be accessed without spawning directly onto them
                     // this _only_ works as expected because clear_entities() is called at the end of every frame.
-                    render_app.world.entities_mut().flush_as_invalid();
+                    unsafe { render_app.world.entities_mut() }.flush_as_invalid();
                 }
 
                 {