ecs: system params can be in any order, faster compiles, remove foreach

crates/bevy_app/src/app_builder.rs

@@ -4,7 +4,7 @@ use crate::{
     plugin::Plugin,
     stage, startup_stage, PluginGroup, PluginGroupBuilder,
 };
-use bevy_ecs::{FromResources, IntoQuerySystem, Resources, System, World};
+use bevy_ecs::{FromResources, IntoSystem, Resources, System, World};
 
 /// Configure [App]s using the builder pattern
 pub struct AppBuilder {

crates/bevy_asset/src/assets.rs

@@ -2,7 +2,7 @@ use crate::{
     update_asset_storage_system, Asset, AssetLoader, AssetServer, Handle, HandleId, RefChange,
 };
 use bevy_app::{prelude::Events, AppBuilder};
-use bevy_ecs::{FromResources, IntoQuerySystem, ResMut};
+use bevy_ecs::{FromResources, IntoSystem, ResMut};
 use bevy_type_registry::RegisterType;
 use bevy_utils::HashMap;
 use crossbeam_channel::Sender;

crates/bevy_asset/src/lib.rs

@@ -31,7 +31,7 @@ pub mod prelude {
 }
 
 use bevy_app::{prelude::Plugin, AppBuilder};
-use bevy_ecs::IntoQuerySystem;
+use bevy_ecs::IntoSystem;
 use bevy_type_registry::RegisterType;
 
 /// Adds support for Assets to an App. Assets are typed collections with change tracking, which are added as App Resources.

crates/bevy_diagnostic/src/frame_time_diagnostics_plugin.rs

@@ -1,7 +1,7 @@
 use crate::{Diagnostic, DiagnosticId, Diagnostics};
 use bevy_app::prelude::*;
 use bevy_core::Time;
-use bevy_ecs::{IntoQuerySystem, Res, ResMut};
+use bevy_ecs::{IntoSystem, Res, ResMut};
 
 /// Adds "frame time" diagnostic to an App, specifically "frame time", "fps" and "frame count"
 #[derive(Default)]

crates/bevy_diagnostic/src/lib.rs

@@ -18,7 +18,7 @@ impl Plugin for DiagnosticsPlugin {
         app.init_resource::<Diagnostics>();
         #[cfg(feature = "profiler")]
         {
-            use bevy_ecs::IntoQuerySystem;
+            use bevy_ecs::IntoSystem;
             app.add_resource::<Box<dyn bevy_ecs::Profiler>>(Box::new(
                 system_profiler::SystemProfiler::default(),
             ))

crates/bevy_diagnostic/src/print_diagnostics_plugin.rs

@@ -1,7 +1,7 @@
 use super::{Diagnostic, DiagnosticId, Diagnostics};
 use bevy_app::prelude::*;
 use bevy_core::{Time, Timer};
-use bevy_ecs::{IntoQuerySystem, Res, ResMut};
+use bevy_ecs::{IntoSystem, Res, ResMut};
 use std::time::Duration;
 
 /// An App Plugin that prints diagnostics to the console

crates/bevy_ecs/src/lib.rs

@@ -12,9 +12,7 @@ pub use world::*;
 pub mod prelude {
     pub use crate::{
         resource::{ChangedRes, FromResources, Local, OrRes, Res, ResMut, Resource, Resources},
-        system::{
-            Commands, IntoForEachSystem, IntoQuerySystem, IntoThreadLocalSystem, Query, System,
-        },
+        system::{Commands, IntoSystem, IntoThreadLocalSystem, Query, System},
         world::WorldBuilderSource,
         Added, Bundle, Changed, Component, Entity, Mut, Mutated, Or, QuerySet, Ref, RefMut, With,
         Without, World,

crates/bevy_ecs/src/resource/resource_query.rs

@@ -194,6 +194,18 @@ pub trait FetchResource<'a>: Sized {
     }
 }
 
+pub trait ResourceFetchSelf {
+    #[allow(clippy::missing_safety_doc)]
+    unsafe fn get(resources: &Resources, system_id: Option<SystemId>) -> Self;
+}
+
+impl<'a, Q: ResourceQuery<Fetch=F>, F: FetchResource<'a, Item=Q>> ResourceFetchSelf for Q {
+    unsafe fn get(resources: &Resources, system_id: Option<SystemId>) -> Q {
+        let resources: &'a Resources = std::mem::transmute(resources);
+        <Q::Fetch as FetchResource<'a>>::get(resources, system_id)
+    }
+}
+
 impl<'a, T: Resource> ResourceQuery for Res<'a, T> {
     type Fetch = FetchResourceRead<T>;
 }