Store QueryState in Query as a Cow and remove distinct QueryLens type

benches/benches/bevy_ecs/change_detection.rs

@@ -71,7 +71,7 @@ fn setup<T: Component + Default>(entity_count: u32) -> World {
 
 // create a cached query in setup to avoid extra costs in each iter
 fn generic_filter_query<F: QueryFilter>(world: &mut World) -> QueryState<Entity, F> {
-    world.query_filtered::<Entity, F>()
+    world.query_state_filtered::<Entity, F>()
 }
 
 fn generic_bench<P: Copy>(
@@ -135,7 +135,7 @@ fn all_changed_detection_generic<T: Component + Default + BenchModify>(
                 || {
                     let mut world = setup::<T>(entity_count);
                     world.clear_trackers();
-                    let mut query = world.query::<&mut T>();
+                    let mut query = world.query_state::<&mut T>();
                     for mut component in query.iter_mut(&mut world) {
                         black_box(component.bench_modify());
                     }
@@ -185,7 +185,7 @@ fn few_changed_detection_generic<T: Component + Default + BenchModify>(
                 || {
                     let mut world = setup::<T>(entity_count);
                     world.clear_trackers();
-                    let mut query = world.query::<&mut T>();
+                    let mut query = world.query_state::<&mut T>();
                     let mut to_modify: Vec<bevy_ecs::prelude::Mut<T>> =
                         query.iter_mut(&mut world).collect();
                     to_modify.shuffle(&mut deterministic_rand());
@@ -316,7 +316,7 @@ fn multiple_archetype_none_changed_detection_generic<T: Component + Default + Be
                     let mut world = World::new();
                     add_archetypes_entities::<T>(&mut world, archetype_count, entity_count);
                     world.clear_trackers();
-                    let mut query = world.query::<(
+                    let mut query = world.query_state::<(
                         Option<&mut Data<0>>,
                         Option<&mut Data<1>>,
                         Option<&mut Data<2>>,

benches/benches/bevy_ecs/iteration/iter_frag.rs

@@ -23,7 +23,7 @@ impl<'w> Benchmark<'w> {
 
         create_entities!(world; A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z);
 
-        let query = world.query::<&mut Data>();
+        let query = world.query_state::<&mut Data>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_frag_foreach.rs

@@ -23,7 +23,7 @@ impl<'w> Benchmark<'w> {
 
         create_entities!(world; A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z);
 
-        let query = world.query::<&mut Data>();
+        let query = world.query_state::<&mut Data>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_frag_foreach_sparse.rs

@@ -34,7 +34,7 @@ impl<'w> Benchmark<'w> {
         create_entities!(world; C70, C71, C72, C73, C74, C75, C76, C77, C78, C79);
         create_entities!(world; C80, C81, C82, C83, C84, C85, C86, C87, C88, C89);
         create_entities!(world; C90, C91, C92, C93, C94, C95, C96, C97, C98, C99);
-        let query = world.query::<&mut Data>();
+        let query = world.query_state::<&mut Data>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_frag_foreach_wide.rs

@@ -51,7 +51,7 @@ impl<'w> Benchmark<'w> {
 
         create_entities!(world; A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z);
 
-        let query = world.query();
+        let query = world.query_state();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_frag_foreach_wide_sparse.rs

@@ -61,7 +61,7 @@ impl<'w> Benchmark<'w> {
         create_entities!(world; C70, C71, C72, C73, C74, C75, C76, C77, C78, C79);
         create_entities!(world; C80, C81, C82, C83, C84, C85, C86, C87, C88, C89);
         create_entities!(world; C90, C91, C92, C93, C94, C95, C96, C97, C98, C99);
-        let query = world.query();
+        let query = world.query_state();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_frag_sparse.rs

@@ -34,7 +34,7 @@ impl<'w> Benchmark<'w> {
         create_entities!(world; C70, C71, C72, C73, C74, C75, C76, C77, C78, C79);
         create_entities!(world; C80, C81, C82, C83, C84, C85, C86, C87, C88, C89);
         create_entities!(world; C90, C91, C92, C93, C94, C95, C96, C97, C98, C99);
-        let query = world.query::<&mut Data>();
+        let query = world.query_state::<&mut Data>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_frag_wide.rs

@@ -51,7 +51,7 @@ impl<'w> Benchmark<'w> {
 
         create_entities!(world; A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z);
 
-        let query = world.query();
+        let query = world.query_state();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_frag_wide_sparse.rs

@@ -61,7 +61,7 @@ impl<'w> Benchmark<'w> {
         create_entities!(world; C70, C71, C72, C73, C74, C75, C76, C77, C78, C79);
         create_entities!(world; C80, C81, C82, C83, C84, C85, C86, C87, C88, C89);
         create_entities!(world; C90, C91, C92, C93, C94, C95, C96, C97, C98, C99);
-        let query = world.query();
+        let query = world.query_state();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_simple.rs

@@ -29,7 +29,7 @@ impl<'w> Benchmark<'w> {
             .take(10_000),
         );
 
-        let query = world.query::<(&Velocity, &mut Position)>();
+        let query = world.query_state::<(&Velocity, &mut Position)>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_simple_foreach.rs

@@ -29,7 +29,7 @@ impl<'w> Benchmark<'w> {
             .take(10_000),
         );
 
-        let query = world.query::<(&Velocity, &mut Position)>();
+        let query = world.query_state::<(&Velocity, &mut Position)>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_simple_foreach_hybrid.rs

@@ -30,7 +30,7 @@ impl<'w> Benchmark<'w> {
             world.entity_mut(e).despawn();
         }
 
-        let query = world.query::<(&mut TableData, &SparseData)>();
+        let query = world.query_state::<(&mut TableData, &SparseData)>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_simple_foreach_sparse_set.rs

@@ -31,7 +31,7 @@ impl<'w> Benchmark<'w> {
             .take(10_000),
         );
 
-        let query = world.query::<(&Velocity, &mut Position)>();
+        let query = world.query_state::<(&Velocity, &mut Position)>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_simple_foreach_wide.rs

@@ -51,7 +51,7 @@ impl<'w> Benchmark<'w> {
             .take(10_000),
         );
 
-        let query = world.query();
+        let query = world.query_state();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_simple_foreach_wide_sparse_set.rs

@@ -53,7 +53,7 @@ impl<'w> Benchmark<'w> {
             .take(10_000),
         );
 
-        let query = world.query();
+        let query = world.query_state();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_simple_sparse_set.rs

@@ -31,7 +31,7 @@ impl<'w> Benchmark<'w> {
             .take(10_000),
         );
 
-        let query = world.query::<(&Velocity, &mut Position)>();
+        let query = world.query_state::<(&Velocity, &mut Position)>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_simple_wide.rs

@@ -51,7 +51,7 @@ impl<'w> Benchmark<'w> {
             .take(10_000),
         );
 
-        let query = world.query();
+        let query = world.query_state();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/iter_simple_wide_sparse_set.rs

@@ -53,7 +53,7 @@ impl<'w> Benchmark<'w> {
             .take(10_000),
         );
 
-        let query = world.query();
+        let query = world.query_state();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/par_iter_simple.rs

@@ -60,7 +60,7 @@ impl<'w> Benchmark<'w> {
             insert_if_bit_enabled::<15>(&mut e, i);
         }
 
-        let query = world.query::<(&Velocity, &mut Position)>();
+        let query = world.query_state::<(&Velocity, &mut Position)>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/iteration/par_iter_simple_foreach_hybrid.rs

@@ -32,7 +32,7 @@ impl<'w> Benchmark<'w> {
             world.entity_mut(e).despawn();
         }
 
-        let query = world.query::<(&mut TableData, &SparseData)>();
+        let query = world.query_state::<(&mut TableData, &SparseData)>();
         Self(world, query)
     }
 

benches/benches/bevy_ecs/world/world_get.rs

@@ -100,7 +100,7 @@ pub fn world_query_get(criterion: &mut Criterion) {
     for entity_count in RANGE.map(|i| i * 10_000) {
         group.bench_function(format!("{}_entities_table", entity_count), |bencher| {
             let mut world = setup::<Table>(entity_count);
-            let mut query = world.query::<&Table>();
+            let mut query = world.query_state::<&Table>();
 
             bencher.iter(|| {
                 for i in 0..entity_count {
@@ -118,7 +118,7 @@ pub fn world_query_get(criterion: &mut Criterion) {
                 WideTable<4>,
                 WideTable<5>,
             )>(entity_count);
-            let mut query = world.query::<(
+            let mut query = world.query_state::<(
                 &WideTable<0>,
                 &WideTable<1>,
                 &WideTable<2>,
@@ -136,7 +136,7 @@ pub fn world_query_get(criterion: &mut Criterion) {
         });
         group.bench_function(format!("{}_entities_sparse", entity_count), |bencher| {
             let mut world = setup::<Sparse>(entity_count);
-            let mut query = world.query::<&Sparse>();
+            let mut query = world.query_state::<&Sparse>();
 
             bencher.iter(|| {
                 for i in 0..entity_count {
@@ -156,7 +156,7 @@ pub fn world_query_get(criterion: &mut Criterion) {
                     WideSparse<4>,
                     WideSparse<5>,
                 )>(entity_count);
-                let mut query = world.query::<(
+                let mut query = world.query_state::<(
                     &WideSparse<0>,
                     &WideSparse<1>,
                     &WideSparse<2>,
@@ -186,7 +186,7 @@ pub fn world_query_iter(criterion: &mut Criterion) {
     for entity_count in RANGE.map(|i| i * 10_000) {
         group.bench_function(format!("{}_entities_table", entity_count), |bencher| {
             let mut world = setup::<Table>(entity_count);
-            let mut query = world.query::<&Table>();
+            let mut query = world.query_state::<&Table>();
 
             bencher.iter(|| {
                 let mut count = 0;
@@ -200,7 +200,7 @@ pub fn world_query_iter(criterion: &mut Criterion) {
         });
         group.bench_function(format!("{}_entities_sparse", entity_count), |bencher| {
             let mut world = setup::<Sparse>(entity_count);
-            let mut query = world.query::<&Sparse>();
+            let mut query = world.query_state::<&Sparse>();
 
             bencher.iter(|| {
                 let mut count = 0;
@@ -225,7 +225,7 @@ pub fn world_query_for_each(criterion: &mut Criterion) {
     for entity_count in RANGE.map(|i| i * 10_000) {
         group.bench_function(format!("{}_entities_table", entity_count), |bencher| {
             let mut world = setup::<Table>(entity_count);
-            let mut query = world.query::<&Table>();
+            let mut query = world.query_state::<&Table>();
 
             bencher.iter(|| {
                 let mut count = 0;
@@ -239,7 +239,7 @@ pub fn world_query_for_each(criterion: &mut Criterion) {
         });
         group.bench_function(format!("{}_entities_sparse", entity_count), |bencher| {
             let mut world = setup::<Sparse>(entity_count);
-            let mut query = world.query::<&Sparse>();
+            let mut query = world.query_state::<&Sparse>();
 
             bencher.iter(|| {
                 let mut count = 0;

crates/bevy_core/src/name.rs

@@ -226,7 +226,7 @@ mod tests {
         let e1 = world.spawn_empty().id();
         let name = Name::new("MyName");
         let e2 = world.spawn(name.clone()).id();
-        let mut query = world.query::<NameOrEntity>();
+        let mut query = world.query_state::<NameOrEntity>();
         let d1 = query.get(&world, e1).unwrap();
         let d2 = query.get(&world, e2).unwrap();
         // NameOrEntity Display for entities without a Name should be {index}v{generation}

crates/bevy_core_pipeline/src/taa/mod.rs

@@ -357,7 +357,7 @@ impl SpecializedRenderPipeline for TaaPipeline {
 }
 
 fn extract_taa_settings(mut commands: Commands, mut main_world: ResMut<MainWorld>) {
-    let mut cameras_3d = main_world.query_filtered::<(
+    let mut cameras_3d = main_world.query_state_filtered::<(
         &RenderEntity,
         &Camera,
         &Projection,

crates/bevy_ecs/macros/src/query_data.rs

@@ -325,6 +325,14 @@ pub fn derive_query_data_impl(input: TokenStream) -> TokenStream {
                 #(#named_field_idents: <#field_types as #path::query::WorldQuery>::State,)*
             }
 
+            impl #user_impl_generics ::core::clone::Clone for #state_struct_name #user_ty_generics #user_where_clauses {
+                fn clone(&self) -> Self {
+                    Self {
+                        #(#named_field_idents: ::core::clone::Clone::clone(&self.#named_field_idents),)*
+                    }
+                }
+            }
+
             #mutable_world_query_impl
 
             #read_only_impl

crates/bevy_ecs/macros/src/query_filter.rs

@@ -158,6 +158,14 @@ pub fn derive_query_filter_impl(input: TokenStream) -> TokenStream {
                 #(#named_field_idents: <#field_types as #path::query::WorldQuery>::State,)*
             }
 
+            impl #user_impl_generics ::core::clone::Clone for #state_struct_name #user_ty_generics #user_where_clauses {
+                fn clone(&self) -> Self {
+                    Self {
+                        #(#named_field_idents: ::core::clone::Clone::clone(&self.#named_field_idents),)*
+                    }
+                }
+            }
+
             #world_query_impl
 
             #filter_impl

crates/bevy_ecs/src/change_detection.rs

@@ -1282,7 +1282,7 @@ mod tests {
 
         // Since the world is always ahead, as long as changes can't get older than `u32::MAX` (which we ensure),
         // the wrapping difference will always be positive, so wraparound doesn't matter.
-        let mut query = world.query::<Ref<C>>();
+        let mut query = world.query_state::<Ref<C>>();
         assert!(query.single(&world).is_changed());
     }
 
@@ -1297,7 +1297,7 @@ mod tests {
         *world.change_tick.get_mut() += MAX_CHANGE_AGE + CHECK_TICK_THRESHOLD;
         let change_tick = world.change_tick();
 
-        let mut query = world.query::<Ref<C>>();
+        let mut query = world.query_state::<Ref<C>>();
         for tracker in query.iter(&world) {
             let ticks_since_insert = change_tick.relative_to(*tracker.ticks.added).get();
             let ticks_since_change = change_tick.relative_to(*tracker.ticks.changed).get();

crates/bevy_ecs/src/component.rs

@@ -448,7 +448,7 @@ pub type ComponentHook = for<'w> fn(DeferredWorld<'w>, Entity, ComponentId);
 /// world.init_resource::<TrackedEntities>();
 ///
 /// // No entities with `MyTrackedComponent` have been added yet, so we can safely add component hooks
-/// let mut tracked_component_query = world.query::<&MyTrackedComponent>();
+/// let mut tracked_component_query = world.query_state::<&MyTrackedComponent>();
 /// assert!(tracked_component_query.iter(&world).next().is_none());
 ///
 /// world.register_component_hooks::<MyTrackedComponent>().on_add(|mut world, entity, _component_id| {