reexport entity set collections in entity module (#18413)

# Objective

Unlike for their helper typers, the import paths for
`unique_array::UniqueEntityArray`, `unique_slice::UniqueEntitySlice`,
`unique_vec::UniqueEntityVec`, `hash_set::EntityHashSet`,
`hash_map::EntityHashMap`, `index_set::EntityIndexSet`,
`index_map::EntityIndexMap` are quite redundant.

When looking at the structure of `hashbrown`, we can also see that while
both `HashSet` and `HashMap` have their own modules, the main types
themselves are re-exported to the crate level.

## Solution

Re-export the types in their shared `entity` parent module, and simplify
the imports where they're used.

Author: Victoronz

benches/benches/bevy_ecs/world/entity_hash.rs

@@ -1,4 +1,4 @@
-use bevy_ecs::entity::{hash_set::EntityHashSet, Entity};
+use bevy_ecs::entity::{Entity, EntityHashSet};
 use criterion::{BenchmarkId, Criterion, Throughput};
 use rand::{Rng, SeedableRng};
 use rand_chacha::ChaCha8Rng;

crates/bevy_core_pipeline/src/oit/resolve/mod.rs

@@ -6,7 +6,7 @@ use bevy_app::Plugin;
 use bevy_asset::{load_internal_asset, weak_handle, Handle};
 use bevy_derive::Deref;
 use bevy_ecs::{
-    entity::{hash_map::EntityHashMap, hash_set::EntityHashSet},
+    entity::{EntityHashMap, EntityHashSet},
     prelude::*,
 };
 use bevy_image::BevyDefault as _;

crates/bevy_ecs/src/entity/clone_entities.rs

@@ -844,7 +844,7 @@ mod tests {
     use super::ComponentCloneCtx;
     use crate::{
         component::{Component, ComponentCloneBehavior, ComponentDescriptor, StorageType},
-        entity::{hash_map::EntityHashMap, Entity, EntityCloner, SourceComponent},
+        entity::{Entity, EntityCloner, EntityHashMap, SourceComponent},
         prelude::{ChildOf, Children, Resource},
         reflect::{AppTypeRegistry, ReflectComponent, ReflectFromWorld},
         world::{FromWorld, World},

crates/bevy_ecs/src/entity/entity_set.rs

@@ -13,7 +13,7 @@ use core::{
     option, result,
 };
 
-use super::{unique_slice::UniqueEntitySlice, Entity};
+use super::{Entity, UniqueEntitySlice};
 
 use bevy_platform_support::sync::Arc;
 

crates/bevy_ecs/src/entity/map_entities.rs

@@ -108,7 +108,7 @@ impl<A: smallvec::Array<Item = Entity>> MapEntities for SmallVec<A> {
 ///
 /// ```
 /// # use bevy_ecs::entity::{Entity, EntityMapper};
-/// # use bevy_ecs::entity::hash_map::EntityHashMap;
+/// # use bevy_ecs::entity::EntityHashMap;
 /// #
 /// pub struct SimpleEntityMapper {
 ///   map: EntityHashMap<Entity>,
@@ -281,7 +281,7 @@ impl<'m> SceneEntityMapper<'m> {
 #[cfg(test)]
 mod tests {
     use crate::{
-        entity::{hash_map::EntityHashMap, Entity, EntityMapper, SceneEntityMapper},
+        entity::{Entity, EntityHashMap, EntityMapper, SceneEntityMapper},
         world::World,
     };
 

crates/bevy_ecs/src/entity/mod.rs

@@ -54,13 +54,23 @@ pub use hash::*;
 pub mod hash_map;
 pub mod hash_set;
 
+pub use hash_map::EntityHashMap;
+pub use hash_set::EntityHashSet;
+
 pub mod index_map;
 pub mod index_set;
 
+pub use index_map::EntityIndexMap;
+pub use index_set::EntityIndexSet;
+
 pub mod unique_array;
 pub mod unique_slice;
 pub mod unique_vec;
 
+pub use unique_array::UniqueEntityArray;
+pub use unique_slice::UniqueEntitySlice;
+pub use unique_vec::UniqueEntityVec;
+
 use crate::{
     archetype::{ArchetypeId, ArchetypeRow},
     change_detection::MaybeLocation,

crates/bevy_ecs/src/entity/unique_slice.rs

@@ -25,10 +25,9 @@ use alloc::{
 use bevy_platform_support::sync::Arc;
 
 use super::{
-    unique_array::UniqueEntityArray,
     unique_vec::{self, UniqueEntityVec},
     Entity, EntitySet, EntitySetIterator, FromEntitySetIterator, TrustedEntityBorrow,
-    UniqueEntityIter,
+    UniqueEntityArray, UniqueEntityIter,
 };
 
 /// A slice that contains only unique entities.

crates/bevy_ecs/src/entity/unique_vec.rs

@@ -20,9 +20,9 @@ use alloc::{
 use bevy_platform_support::sync::Arc;
 
 use super::{
-    unique_array::UniqueEntityArray,
     unique_slice::{self, UniqueEntitySlice},
-    Entity, EntitySet, FromEntitySetIterator, TrustedEntityBorrow, UniqueEntityIter,
+    Entity, EntitySet, FromEntitySetIterator, TrustedEntityBorrow, UniqueEntityArray,
+    UniqueEntityIter,
 };
 
 /// A `Vec` that contains only unique entities.

crates/bevy_ecs/src/observer/mod.rs

@@ -11,7 +11,7 @@ use crate::{
     archetype::ArchetypeFlags,
     change_detection::MaybeLocation,
     component::ComponentId,
-    entity::hash_map::EntityHashMap,
+    entity::EntityHashMap,
     prelude::*,
     system::IntoObserverSystem,
     world::{DeferredWorld, *},

crates/bevy_ecs/src/query/par_iter.rs

@@ -1,7 +1,7 @@
 use crate::{
     batching::BatchingStrategy,
     component::Tick,
-    entity::{unique_vec::UniqueEntityVec, EntityBorrow, TrustedEntityBorrow},
+    entity::{EntityBorrow, TrustedEntityBorrow, UniqueEntityVec},
     world::unsafe_world_cell::UnsafeWorldCell,
 };
 
@@ -363,7 +363,7 @@ impl<'w, 's, D: QueryData, F: QueryFilter, E: TrustedEntityBorrow + Sync>
     ///
     /// ```
     /// use bevy_utils::Parallel;
-    /// use crate::{bevy_ecs::{prelude::{Component, Res, Resource, Entity}, entity::unique_vec::UniqueEntityVec, system::Query}};
+    /// use crate::{bevy_ecs::{prelude::{Component, Res, Resource, Entity}, entity::UniqueEntityVec, system::Query}};
     /// # use core::slice;
     /// # use crate::bevy_ecs::entity::UniqueEntityIter;
     /// # fn some_expensive_operation(_item: &T) -> usize {