Cleanup system sets called labels (#7678)

# Objective

We have a few old system labels that are now system sets but are still named or documented as labels. Documentation also generally mentioned system labels in some places.


## Solution

- Clean up naming and documentation regarding system sets

## Migration Guide

`PrepareAssetLabel` is now called `PrepareAssetSet`

.github/contributing/example_style_guide.md

@@ -38,7 +38,7 @@ For more advice on writing examples, see the [relevant section](../../CONTRIBUTI
 4. In Queries, prefer `With<T>` filters over actually fetching unused data with `&T`.
 5. Prefer disjoint queries using `With` and `Without` over param sets when you need more than one query in a single system.
 6. Prefer structs with named fields over tuple structs except in the case of single-field wrapper types.
-7. Use enum-labels over string-labels for system / schedule / etc. labels.
+7. Use enum-labels over string-labels for app / schedule / etc. labels.
 
 ## "Feature" examples
 

benches/benches/bevy_ecs/scheduling/schedule.rs

@@ -64,11 +64,11 @@ pub fn build_schedule(criterion: &mut Criterion) {
     // Use multiple different kinds of label to ensure that dynamic dispatch
     // doesn't somehow get optimized away.
     #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-    struct NumLabel(usize);
+    struct NumSet(usize);
     #[derive(Debug, Clone, Copy, SystemSet, PartialEq, Eq, Hash)]
-    struct DummyLabel;
+    struct DummySet;
 
-    impl SystemSet for NumLabel {
+    impl SystemSet for NumSet {
         fn dyn_clone(&self) -> Box<dyn SystemSet> {
             Box::new(self.clone())
         }
@@ -81,7 +81,7 @@ pub fn build_schedule(criterion: &mut Criterion) {
     // Method: generate a set of `graph_size` systems which have a One True Ordering.
     // Add system to the schedule with full constraints. Hopefully this should be maximimally
     // difficult for bevy to figure out.
-    let labels: Vec<_> = (0..1000).map(|i| NumLabel(i)).collect();
+    let labels: Vec<_> = (0..1000).map(|i| NumSet(i)).collect();
 
     // Benchmark graphs of different sizes.
     for graph_size in [100, 500, 1000] {
@@ -100,12 +100,12 @@ pub fn build_schedule(criterion: &mut Criterion) {
         group.bench_function(format!("{graph_size}_schedule"), |bencher| {
             bencher.iter(|| {
                 let mut app = App::new();
-                app.add_system(empty_system.in_set(DummyLabel));
+                app.add_system(empty_system.in_set(DummySet));
 
                 // Build a fully-connected dependency graph describing the One True Ordering.
                 // Not particularly realistic but this can be refined later.
                 for i in 0..graph_size {
-                    let mut sys = empty_system.in_set(labels[i]).before(DummyLabel);
+                    let mut sys = empty_system.in_set(labels[i]).before(DummySet);
                     for label in labels.iter().take(i) {
                         sys = sys.after(*label);
                     }

crates/bevy_app/src/app.rs

@@ -313,12 +313,12 @@ impl App {
     /// for each state variant, an instance of [`apply_state_transition::<S>`] in
     /// [`CoreSet::StateTransitions`] so that transitions happen before [`CoreSet::Update`] and
     /// a instance of [`run_enter_schedule::<S>`] in [`CoreSet::StateTransitions`] with a
-    /// with a [`run_once`](`run_once_condition`) condition to run the on enter schedule of the
+    /// [`run_once`](`run_once_condition`) condition to run the on enter schedule of the
     /// initial state.
     ///
     /// This also adds an [`OnUpdate`] system set for each state variant,
-    /// which run during [`CoreSet::Update`] after the transitions are applied.
-    /// These systems sets only run if the [`State<S>`] resource matches their label.
+    /// which runs during [`CoreSet::Update`] after the transitions are applied.
+    /// These system sets only run if the [`State<S>`] resource matches the respective state variant.
     ///
     /// If you would like to control how other systems run based on the current state,
     /// you can emulate this behavior using the [`in_state`] [`Condition`](bevy_ecs::schedule::Condition).

crates/bevy_app/src/lib.rs

@@ -124,7 +124,7 @@ impl CoreSet {
     /// Sets up the base structure of [`CoreSchedule::Main`].
     ///
     /// The sets defined in this enum are configured to run in order,
-    /// and a copy of [`apply_system_buffers`] is inserted at each `*Flush` label.
+    /// and a copy of [`apply_system_buffers`] is inserted into each `*Flush` set.
     pub fn base_schedule() -> Schedule {
         use CoreSet::*;
         let mut schedule = Schedule::new();
@@ -185,7 +185,7 @@ impl StartupSet {
     /// Sets up the base structure of [`CoreSchedule::Startup`].
     ///
     /// The sets defined in this enum are configured to run in order,
-    /// and a copy of [`apply_system_buffers`] is inserted at each `*Flush` label.
+    /// and a copy of [`apply_system_buffers`] is inserted into each `*Flush` set.
     pub fn base_schedule() -> Schedule {
         use StartupSet::*;
         let mut schedule = Schedule::new();

crates/bevy_asset/src/debug_asset_server.rs

@@ -32,7 +32,7 @@ impl DerefMut for DebugAssetApp {
     }
 }
 
-/// A label describing the system that runs [`DebugAssetApp`].
+/// A set containing the system that runs [`DebugAssetApp`].
 #[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
 pub struct DebugAssetAppRun;
 

crates/bevy_ecs/macros/src/set.rs

@@ -5,12 +5,12 @@ use syn::parse::{Parse, ParseStream};
 pub static SYSTEM_SET_ATTRIBUTE_NAME: &str = "system_set";
 pub static BASE_ATTRIBUTE_NAME: &str = "base";
 
-/// Derive a label trait
+/// Derive a set trait
 ///
 /// # Args
 ///
-/// - `input`: The [`syn::DeriveInput`] for struct that is deriving the label trait
-/// - `trait_path`: The path [`syn::Path`] to the label trait
+/// - `input`: The [`syn::DeriveInput`] for the struct that we want to derive the set trait for
+/// - `trait_path`: The [`syn::Path`] to the set trait
 pub fn derive_set(input: syn::DeriveInput, trait_path: &syn::Path) -> TokenStream {
     let ident = input.ident;
 

crates/bevy_pbr/src/material.rs

@@ -21,7 +21,7 @@ use bevy_render::{
     extract_component::ExtractComponentPlugin,
     mesh::{Mesh, MeshVertexBufferLayout},
     prelude::Image,
-    render_asset::{PrepareAssetLabel, RenderAssets},
+    render_asset::{PrepareAssetSet, RenderAssets},
     render_phase::{
         AddRenderCommand, DrawFunctions, PhaseItem, RenderCommand, RenderCommandResult,
         RenderPhase, SetItemPipeline, TrackedRenderPass,
@@ -199,7 +199,7 @@ where
                 .add_system(
                     prepare_materials::<M>
                         .in_set(RenderSet::Prepare)
-                        .after(PrepareAssetLabel::PreAssetPrepare),
+                        .after(PrepareAssetSet::PreAssetPrepare),
                 )
                 .add_system(queue_material_meshes::<M>.in_set(RenderSet::Queue));
         }

crates/bevy_render/src/lib.rs

@@ -105,7 +105,7 @@ impl RenderSet {
     /// Sets up the base structure of the rendering [`Schedule`].
     ///
     /// The sets defined in this enum are configured to run in order,
-    /// and a copy of [`apply_system_buffers`] is inserted at each `*Flush` label.
+    /// and a copy of [`apply_system_buffers`] is inserted into each `*Flush` set.
     pub fn base_schedule() -> Schedule {
         use RenderSet::*;
 

crates/bevy_render/src/render_asset.rs

@@ -41,7 +41,7 @@ pub trait RenderAsset: Asset {
 }
 
 #[derive(Clone, Hash, Debug, Default, PartialEq, Eq, SystemSet)]
-pub enum PrepareAssetLabel {
+pub enum PrepareAssetSet {
     PreAssetPrepare,
     #[default]
     AssetPrepare,
@@ -54,14 +54,14 @@ pub enum PrepareAssetLabel {
 /// Therefore it sets up the [`ExtractSchedule`](crate::ExtractSchedule) and
 /// [`RenderSet::Prepare`](crate::RenderSet::Prepare) steps for the specified [`RenderAsset`].
 pub struct RenderAssetPlugin<A: RenderAsset> {
-    prepare_asset_label: PrepareAssetLabel,
+    prepare_asset_set: PrepareAssetSet,
     phantom: PhantomData<fn() -> A>,
 }
 
 impl<A: RenderAsset> RenderAssetPlugin<A> {
-    pub fn with_prepare_asset_label(prepare_asset_label: PrepareAssetLabel) -> Self {
+    pub fn with_prepare_asset_set(prepare_asset_set: PrepareAssetSet) -> Self {
         Self {
-            prepare_asset_label,
+            prepare_asset_set,
             phantom: PhantomData,
         }
     }
@@ -70,7 +70,7 @@ impl<A: RenderAsset> RenderAssetPlugin<A> {
 impl<A: RenderAsset> Default for RenderAssetPlugin<A> {
     fn default() -> Self {
         Self {
-            prepare_asset_label: Default::default(),
+            prepare_asset_set: Default::default(),
             phantom: PhantomData,
         }
     }
@@ -82,9 +82,9 @@ impl<A: RenderAsset> Plugin for RenderAssetPlugin<A> {
             render_app
                 .configure_sets(
                     (
-                        PrepareAssetLabel::PreAssetPrepare,
-                        PrepareAssetLabel::AssetPrepare,
-                        PrepareAssetLabel::PostAssetPrepare,
+                        PrepareAssetSet::PreAssetPrepare,
+                        PrepareAssetSet::AssetPrepare,
+                        PrepareAssetSet::PostAssetPrepare,
                     )
                         .chain()
                         .in_set(RenderSet::Prepare),
@@ -93,7 +93,7 @@ impl<A: RenderAsset> Plugin for RenderAssetPlugin<A> {
                 .init_resource::<RenderAssets<A>>()
                 .init_resource::<PrepareNextFrameAssets<A>>()
                 .add_system_to_schedule(ExtractSchedule, extract_render_asset::<A>)
-                .add_system(prepare_assets::<A>.in_set(self.prepare_asset_label.clone()));
+                .add_system(prepare_assets::<A>.in_set(self.prepare_asset_set.clone()));
         }
     }
 }

crates/bevy_render/src/texture/mod.rs

@@ -27,7 +27,7 @@ pub use image_texture_loader::*;
 pub use texture_cache::*;
 
 use crate::{
-    render_asset::{PrepareAssetLabel, RenderAssetPlugin},
+    render_asset::{PrepareAssetSet, RenderAssetPlugin},
     renderer::RenderDevice,
     RenderApp, RenderSet,
 };
@@ -84,8 +84,8 @@ impl Plugin for ImagePlugin {
             app.init_asset_loader::<HdrTextureLoader>();
         }
 
-        app.add_plugin(RenderAssetPlugin::<Image>::with_prepare_asset_label(
-            PrepareAssetLabel::PreAssetPrepare,
+        app.add_plugin(RenderAssetPlugin::<Image>::with_prepare_asset_set(
+            PrepareAssetSet::PreAssetPrepare,
         ))
         .register_type::<Image>()
         .add_asset::<Image>()

crates/bevy_render/src/view/visibility/mod.rs

@@ -91,7 +91,7 @@ impl ComputedVisibility {
 
     /// Whether this entity is visible to something this frame. This is true if and only if [`Self::is_visible_in_hierarchy`] and [`Self::is_visible_in_view`]
     /// are true. This is the canonical method to call to determine if an entity should be drawn.
-    /// This value is updated in [`CoreSet::PostUpdate`] during the [`VisibilitySystems::CheckVisibility`] system label.
+    /// This value is updated in [`CoreSet::PostUpdate`] by the [`VisibilitySystems::CheckVisibility`] system set.
     /// Reading it during [`CoreSet::Update`] will yield the value from the previous frame.
     #[inline]
     pub fn is_visible(&self) -> bool {
@@ -356,7 +356,7 @@ fn propagate_recursive(
 
 /// System updating the visibility of entities each frame.
 ///
-/// The system is labelled with [`VisibilitySystems::CheckVisibility`]. Each frame, it updates the
+/// The system is part of the [`VisibilitySystems::CheckVisibility`] set. Each frame, it updates the
 /// [`ComputedVisibility`] of all entities, and for each view also compute the [`VisibleEntities`]
 /// for that view.
 pub fn check_visibility(

crates/bevy_sprite/src/mesh2d/material.rs

@@ -16,7 +16,7 @@ use bevy_render::{
     extract_component::ExtractComponentPlugin,
     mesh::{Mesh, MeshVertexBufferLayout},
     prelude::Image,
-    render_asset::{PrepareAssetLabel, RenderAssets},
+    render_asset::{PrepareAssetSet, RenderAssets},
     render_phase::{
         AddRenderCommand, DrawFunctions, PhaseItem, RenderCommand, RenderCommandResult,
         RenderPhase, SetItemPipeline, TrackedRenderPass,
@@ -162,7 +162,7 @@ where
                 .add_system(
                     prepare_materials_2d::<M>
                         .in_set(RenderSet::Prepare)
-                        .after(PrepareAssetLabel::PreAssetPrepare),
+                        .after(PrepareAssetSet::PreAssetPrepare),
                 )
                 .add_system(queue_material2d_meshes::<M>.in_set(RenderSet::Queue));
         }

crates/bevy_transform/src/components/global_transform.rs

@@ -21,7 +21,7 @@ use bevy_reflect::{std_traits::ReflectDefault, FromReflect, Reflect};
 ///
 /// [`GlobalTransform`] is the position of an entity relative to the reference frame.
 ///
-/// [`GlobalTransform`] is updated from [`Transform`] in the systems labeled
+/// [`GlobalTransform`] is updated from [`Transform`] by systems in the system set
 /// [`TransformPropagate`](crate::TransformSystem::TransformPropagate).
 ///
 /// This system runs during [`CoreSet::PostUpdate`](crate::CoreSet::PostUpdate). If you

crates/bevy_transform/src/components/transform.rs

@@ -20,7 +20,7 @@ use std::ops::Mul;
 ///
 /// [`GlobalTransform`] is the position of an entity relative to the reference frame.
 ///
-/// [`GlobalTransform`] is updated from [`Transform`] in the systems labeled
+/// [`GlobalTransform`] is updated from [`Transform`] by systems in the system set
 /// [`TransformPropagate`](crate::TransformSystem::TransformPropagate).
 ///
 /// This system runs during [`CoreSet::PostUpdate`](crate::CoreSet::PostUpdate). If you

crates/bevy_transform/src/lib.rs

@@ -37,7 +37,7 @@ use systems::{propagate_transforms, sync_simple_transforms};
 ///
 /// [`GlobalTransform`] is the position of an entity relative to the reference frame.
 ///
-/// [`GlobalTransform`] is updated from [`Transform`] in the systems labeled
+/// [`GlobalTransform`] is updated from [`Transform`] by systems in the system set
 /// [`TransformPropagate`](crate::TransformSystem::TransformPropagate).
 ///
 /// This system runs during [`CoreSet::PostUpdate`](crate::CoreSet::PostUpdate). If you
@@ -77,7 +77,7 @@ impl From<Transform> for TransformBundle {
         Self::from_transform(transform)
     }
 }
-/// Label enum for the systems relating to transform propagation
+/// Set enum for the systems relating to transform propagation
 #[derive(Debug, Hash, PartialEq, Eq, Clone, SystemSet)]
 pub enum TransformSystem {
     /// Propagates changes in transform to children's [`GlobalTransform`](crate::components::GlobalTransform)