use InteriorMutableWorld for System and ParamState

Author: jakobhellermann

crates/bevy_ecs/macros/src/lib.rs

@@ -292,7 +292,7 @@ pub fn impl_param_set(_input: TokenStream) -> TokenStream {
                 unsafe fn get_param<'w, 's>(
                     state: &'s mut Self::State,
                     system_meta: &SystemMeta,
-                    world: &'w World,
+                    world: InteriorMutableWorld<'w>,
                     change_tick: u32,
                 ) -> Self::Item<'w, 's> {
                     ParamSet {
@@ -496,7 +496,7 @@ pub fn derive_system_param(input: TokenStream) -> TokenStream {
                 unsafe fn get_param<'w2, 's2>(
                     state: &'s2 mut Self::State,
                     system_meta: &#path::system::SystemMeta,
-                    world: &'w2 #path::world::World,
+                    world: #path::world::interior_mutable_world::InteriorMutableWorld<'w2>,
                     change_tick: u32,
                 ) -> Self::Item<'w2, 's2> {
                     let (#(#tuple_patterns,)*) = <

crates/bevy_ecs/src/schedule/executor_parallel.rs

@@ -2,7 +2,7 @@ use crate::{
     archetype::ArchetypeComponentId,
     query::Access,
     schedule::{ParallelSystemExecutor, SystemContainer},
-    world::World,
+    world::{interior_mutable_world::InteriorMutableWorld, World},
 };
 use async_channel::{Receiver, Sender};
 use bevy_tasks::{ComputeTaskPool, Scope, TaskPool};
@@ -124,6 +124,8 @@ impl ParallelSystemExecutor for ParallelExecutor {
             }
         }
 
+        let world = world.as_interior_mutable();
+
         ComputeTaskPool::init(TaskPool::default).scope(|scope| {
             self.prepare_systems(scope, systems, world);
             if self.should_run.count_ones(..) == 0 {
@@ -168,7 +170,7 @@ impl ParallelExecutor {
         &mut self,
         scope: &Scope<'_, 'scope, ()>,
         systems: &'scope mut [SystemContainer],
-        world: &'scope World,
+        world: InteriorMutableWorld<'scope>,
     ) {
         // These are used as a part of a unit test.
         #[cfg(test)]

crates/bevy_ecs/src/system/commands/parallel_scope.rs

@@ -6,6 +6,7 @@ use crate::{
     entity::Entities,
     prelude::World,
     system::{SystemMeta, SystemParam},
+    world::interior_mutable_world::InteriorMutableWorld,
 };
 
 use super::{CommandQueue, Commands};
@@ -70,7 +71,7 @@ unsafe impl SystemParam for ParallelCommands<'_, '_> {
     unsafe fn get_param<'w, 's>(
         state: &'s mut Self::State,
         _: &crate::system::SystemMeta,
-        world: &'w World,
+        world: InteriorMutableWorld<'w>,
         _: u32,
     ) -> Self::Item<'w, 's> {
         ParallelCommands {

crates/bevy_ecs/src/system/exclusive_function_system.rs

@@ -8,7 +8,7 @@ use crate::{
         check_system_change_tick, AsSystemLabel, ExclusiveSystemParam, ExclusiveSystemParamItem,
         IntoSystem, System, SystemMeta, SystemTypeIdLabel,
     },
-    world::{World, WorldId},
+    world::{interior_mutable_world::InteriorMutableWorld, World, WorldId},
 };
 use bevy_ecs_macros::all_tuples;
 use std::{borrow::Cow, marker::PhantomData};
@@ -86,7 +86,11 @@ where
     }
 
     #[inline]
-    unsafe fn run_unsafe(&mut self, _input: Self::In, _world: &World) -> Self::Out {
+    unsafe fn run_unsafe(
+        &mut self,
+        _input: Self::In,
+        _world: InteriorMutableWorld<'_>,
+    ) -> Self::Out {
         panic!("Cannot run exclusive systems with a shared World reference");
     }
 

crates/bevy_ecs/src/system/function_system.rs

@@ -6,7 +6,7 @@ use crate::{
     query::{Access, FilteredAccessSet},
     schedule::{SystemLabel, SystemLabelId},
     system::{check_system_change_tick, ReadOnlySystemParam, System, SystemParam, SystemParamItem},
-    world::{World, WorldId},
+    world::{interior_mutable_world::InteriorMutableWorld, World, WorldId},
 };
 use bevy_ecs_macros::all_tuples;
 use std::{borrow::Cow, fmt::Debug, marker::PhantomData};
@@ -172,15 +172,15 @@ impl<Param: SystemParam> SystemState<Param> {
     {
         self.validate_world_and_update_archetypes(world);
         // SAFETY: Param is read-only and doesn't allow mutable access to World. It also matches the World this SystemState was created with.
-        unsafe { self.get_unchecked_manual(world) }
+        unsafe { self.get_unchecked_manual(world.as_interior_mutable_readonly()) }
     }
 
     /// Retrieve the mutable [`SystemParam`] values.
     #[inline]
     pub fn get_mut<'w, 's>(&'s mut self, world: &'w mut World) -> SystemParamItem<'w, 's, Param> {
         self.validate_world_and_update_archetypes(world);
         // SAFETY: World is uniquely borrowed and matches the World this SystemState was created with.
-        unsafe { self.get_unchecked_manual(world) }
+        unsafe { self.get_unchecked_manual(world.as_interior_mutable()) }
     }
 
     /// Applies all state queued up for [`SystemParam`] values. For example, this will apply commands queued up
@@ -221,7 +221,7 @@ impl<Param: SystemParam> SystemState<Param> {
     #[inline]
     pub unsafe fn get_unchecked_manual<'w, 's>(
         &'s mut self,
-        world: &'w World,
+        world: InteriorMutableWorld<'w>,
     ) -> SystemParamItem<'w, 's, Param> {
         let change_tick = world.increment_change_tick();
         let param = Param::get_param(&mut self.param_state, &self.meta, world, change_tick);
@@ -389,7 +389,7 @@ where
     }
 
     #[inline]
-    unsafe fn run_unsafe(&mut self, input: Self::In, world: &World) -> Self::Out {
+    unsafe fn run_unsafe(&mut self, input: Self::In, world: InteriorMutableWorld<'_>) -> Self::Out {
         let change_tick = world.increment_change_tick();
 
         // Safety:

crates/bevy_ecs/src/system/system.rs

@@ -2,8 +2,12 @@ use bevy_utils::tracing::warn;
 use core::fmt::Debug;
 
 use crate::{
-    archetype::ArchetypeComponentId, change_detection::MAX_CHANGE_AGE, component::ComponentId,
-    query::Access, schedule::SystemLabelId, world::World,
+    archetype::ArchetypeComponentId,
+    change_detection::MAX_CHANGE_AGE,
+    component::ComponentId,
+    query::Access,
+    schedule::SystemLabelId,
+    world::{interior_mutable_world::InteriorMutableWorld, World},
 };
 use std::borrow::Cow;
 
@@ -42,17 +46,14 @@ pub trait System: Send + Sync + 'static {
     ///
     /// # Safety
     ///
-    /// This might access world and resources in an unsafe manner. This should only be called in one
-    /// of the following contexts:
-    ///     1. This system is the only system running on the given world across all threads.
-    ///     2. This system only runs in parallel with other systems that do not conflict with the
-    ///        [`System::archetype_component_access()`].
-    unsafe fn run_unsafe(&mut self, input: Self::In, world: &World) -> Self::Out;
+    /// This function may only be called with a [`InteriorMutableWorld`] that can be used for
+    /// everything listed in [`System::archetype_component_access`].
+    unsafe fn run_unsafe(&mut self, input: Self::In, world: InteriorMutableWorld<'_>) -> Self::Out;
     /// Runs the system with the given input in the world.
     fn run(&mut self, input: Self::In, world: &mut World) -> Self::Out {
         self.update_archetype_component_access(world);
         // SAFETY: world and resources are exclusively borrowed
-        unsafe { self.run_unsafe(input, world) }
+        unsafe { self.run_unsafe(input, world.as_interior_mutable()) }
     }
     fn apply_buffers(&mut self, world: &mut World);
     /// Initialize the system.