Update uses of labels in the repo

Author: joseph-gio

benches/benches/bevy_ecs/scheduling/schedule.rs

@@ -64,14 +64,17 @@ 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)]
-    struct NumLabel(usize);
+    struct NumLabel(u64);
     #[derive(Debug, Clone, Copy, SystemLabel)]
     struct DummyLabel;
 
     impl SystemLabel for NumLabel {
-        fn as_str(&self) -> &'static str {
-            let s = self.0.to_string();
-            Box::leak(s.into_boxed_str())
+        #[inline]
+        fn data(&self) -> u64 {
+            self.0
+        }
+        fn fmt(data: u64, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+            f.debug_tuple("NumLabel").field(&data).finish()
         }
     }
 
@@ -82,10 +85,6 @@ 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 stage with full constraints. Hopefully this should be maximimally
     // difficult for bevy to figure out.
-    // Also, we are performing the `as_label` operation outside of the loop since that
-    // requires an allocation and a leak. This is not something that would be necessary in a
-    // real scenario, just a contrivance for the benchmark.
-    let labels: Vec<_> = (0..1000).map(|i| NumLabel(i).as_label()).collect();
 
     // Benchmark graphs of different sizes.
     for graph_size in [100, 500, 1000] {
@@ -109,12 +108,12 @@ pub fn build_schedule(criterion: &mut Criterion) {
                 // 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.label(labels[i]).before(DummyLabel);
+                    let mut sys = empty_system.label(NumLabel(i)).before(DummyLabel);
                     for a in 0..i {
-                        sys = sys.after(labels[a]);
+                        sys = sys.after(NumLabel(a));
                     }
                     for b in i + 1..graph_size {
-                        sys = sys.before(labels[b]);
+                        sys = sys.before(NumLabel(b));
                     }
                     app.add_system(sys);
                 }

crates/bevy_app/src/app.rs

@@ -379,9 +379,9 @@ impl App {
         stage_label: impl StageLabel,
         system: impl IntoSystemDescriptor<Params>,
     ) -> &mut Self {
-        use std::any::TypeId;
+        let stage_label = stage_label.as_label();
         assert!(
-            stage_label.type_id() != TypeId::of::<StartupStage>(),
+            !stage_label.is::<StartupStage>(),
             "add systems to a startup stage using App::add_startup_system_to_stage"
         );
         self.schedule.add_system_to_stage(stage_label, system);
@@ -414,9 +414,9 @@ impl App {
         stage_label: impl StageLabel,
         system_set: SystemSet,
     ) -> &mut Self {
-        use std::any::TypeId;
+        let stage_label = stage_label.as_label();
         assert!(
-            stage_label.type_id() != TypeId::of::<StartupStage>(),
+            !stage_label.is::<StartupStage>(),
             "add system sets to a startup stage using App::add_startup_system_set_to_stage"
         );
         self.schedule
@@ -952,7 +952,7 @@ impl App {
     pub fn sub_app_mut(&mut self, label: impl AppLabel) -> &mut App {
         match self.get_sub_app_mut(label) {
             Ok(app) => app,
-            Err(label) => panic!("Sub-App with label '{:?}' does not exist", label.as_str()),
+            Err(label) => panic!("Sub-App with label '{:?}' does not exist", label.as_label()),
         }
     }
 
@@ -974,13 +974,13 @@ impl App {
     pub fn sub_app(&self, label: impl AppLabel) -> &App {
         match self.get_sub_app(label) {
             Ok(app) => app,
-            Err(label) => panic!("Sub-App with label '{:?}' does not exist", label.as_str()),
+            Err(label) => panic!("Sub-App with label '{:?}' does not exist", label.as_label()),
         }
     }
 
     /// Retrieves a `SubApp` inside this [`App`] with the given label, if it exists. Otherwise returns
     /// an [`Err`] containing the given label.
-    pub fn get_sub_app(&self, label: impl AppLabel) -> Result<&App, impl AppLabel> {
+    pub fn get_sub_app<L: AppLabel>(&self, label: L) -> Result<&App, L> {
         self.sub_apps
             .get(&label.as_label())
             .map(|sub_app| &sub_app.app)

crates/bevy_ecs/src/schedule/state.rs

@@ -6,7 +6,6 @@ use crate::{
     system::{In, IntoChainSystem, Local, Res, ResMut, Resource},
 };
 use std::{
-    any::TypeId,
     fmt::{self, Debug},
     hash::Hash,
 };
@@ -54,20 +53,16 @@ enum ScheduledOperation<T: StateData> {
     Push(T),
 }
 
-#[derive(Debug, PartialEq, Eq, Clone, Hash)]
-struct DriverLabel(TypeId, &'static str);
-impl RunCriteriaLabel for DriverLabel {
-    fn type_id(&self) -> core::any::TypeId {
-        self.0
-    }
-    fn as_str(&self) -> &'static str {
-        self.1
-    }
-}
-
+struct DriverLabel;
 impl DriverLabel {
-    fn of<T: 'static>() -> Self {
-        Self(TypeId::of::<T>(), std::any::type_name::<T>())
+    fn of<T: 'static>() -> impl RunCriteriaLabel {
+        use std::marker::PhantomData;
+
+        #[derive(RunCriteriaLabel)]
+        #[run_criteria_label(ignore_fields)]
+        struct DriverLabel<T>(PhantomData<fn() -> T>);
+
+        DriverLabel::<T>(PhantomData)
     }
 }
 

crates/bevy_ecs/src/system/function_system.rs

@@ -455,8 +455,11 @@ pub struct SystemTypeIdLabel<T: 'static>(PhantomData<fn() -> T>);
 
 impl<T: 'static> SystemLabel for SystemTypeIdLabel<T> {
     #[inline]
-    fn as_str(&self) -> &'static str {
-        std::any::type_name::<T>()
+    fn data(&self) -> u64 {
+        0
+    }
+    fn fmt(_: u64, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{}", std::any::type_name::<T>())
     }
 }