From ee2487a6e2b91d6df3cb8ecf98cc71e19965a87d Mon Sep 17 00:00:00 2001
From: Christian Hughes <9044780+ItsDoot@users.noreply.github.com>
Date: Wed, 19 Jun 2024 16:06:35 -0500
Subject: [PATCH] Change World::inspect_entity to return an Iterator instead of
 Vec (#13934)

# Objective

Fixes #13933.

## Solution

Changed the return type.

## Testing

Fixed and reused the pre-existing tests for `inspect_entity`.

---

## Migration Guide

- `World::inspect_entity` now returns an `Iterator` instead of a `Vec`.
If you need a `Vec`, immediately collect the iterator:
`world.inspect_entity(entity).collect<Vec<_>>()`
---
 crates/bevy_ecs/src/system/commands/mod.rs |  1 -
 crates/bevy_ecs/src/world/mod.rs           | 17 ++++++++---------
 2 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/crates/bevy_ecs/src/system/commands/mod.rs b/crates/bevy_ecs/src/system/commands/mod.rs
index 028182e69f..15e4861fe0 100644
--- a/crates/bevy_ecs/src/system/commands/mod.rs
+++ b/crates/bevy_ecs/src/system/commands/mod.rs
@@ -1321,7 +1321,6 @@ fn insert_resource<R: Resource>(resource: R) -> impl Command {
 fn log_components(entity: Entity, world: &mut World) {
     let debug_infos: Vec<_> = world
         .inspect_entity(entity)
-        .into_iter()
         .map(|component_info| component_info.name())
         .collect();
     info!("Entity {:?}: {:?}", entity, debug_infos);
diff --git a/crates/bevy_ecs/src/world/mod.rs b/crates/bevy_ecs/src/world/mod.rs
index d509eaa349..9ace589952 100644
--- a/crates/bevy_ecs/src/world/mod.rs
+++ b/crates/bevy_ecs/src/world/mod.rs
@@ -479,7 +479,7 @@ impl World {
 
     /// Returns the components of an [`Entity`] through [`ComponentInfo`].
     #[inline]
-    pub fn inspect_entity(&self, entity: Entity) -> Vec<&ComponentInfo> {
+    pub fn inspect_entity(&self, entity: Entity) -> impl Iterator<Item = &ComponentInfo> {
         let entity_location = self
             .entities()
             .get(entity)
@@ -498,7 +498,6 @@ impl World {
         archetype
             .components()
             .filter_map(|id| self.components().get_info(id))
-            .collect()
     }
 
     /// Returns an [`EntityWorldMut`] for the given `entity` (if it exists) or spawns one if it doesn't exist.
@@ -3162,31 +3161,31 @@ mod tests {
         let bar_id = TypeId::of::<Bar>();
         let baz_id = TypeId::of::<Baz>();
         assert_eq!(
-            to_type_ids(world.inspect_entity(ent0)),
+            to_type_ids(world.inspect_entity(ent0).collect()),
             [Some(foo_id), Some(bar_id), Some(baz_id)].into()
         );
         assert_eq!(
-            to_type_ids(world.inspect_entity(ent1)),
+            to_type_ids(world.inspect_entity(ent1).collect()),
             [Some(foo_id), Some(bar_id)].into()
         );
         assert_eq!(
-            to_type_ids(world.inspect_entity(ent2)),
+            to_type_ids(world.inspect_entity(ent2).collect()),
             [Some(bar_id), Some(baz_id)].into()
         );
         assert_eq!(
-            to_type_ids(world.inspect_entity(ent3)),
+            to_type_ids(world.inspect_entity(ent3).collect()),
             [Some(foo_id), Some(baz_id)].into()
         );
         assert_eq!(
-            to_type_ids(world.inspect_entity(ent4)),
+            to_type_ids(world.inspect_entity(ent4).collect()),
             [Some(foo_id)].into()
         );
         assert_eq!(
-            to_type_ids(world.inspect_entity(ent5)),
+            to_type_ids(world.inspect_entity(ent5).collect()),
             [Some(bar_id)].into()
         );
         assert_eq!(
-            to_type_ids(world.inspect_entity(ent6)),
+            to_type_ids(world.inspect_entity(ent6).collect()),
             [Some(baz_id)].into()
         );
     }