diff --git a/crates/bevy_ecs/examples/mutate_obsover.rs b/crates/bevy_ecs/examples/mutate_obsover.rs
deleted file mode 100644
index 428646ee59d193..00000000000000
--- a/crates/bevy_ecs/examples/mutate_obsover.rs
+++ /dev/null
@@ -1,54 +0,0 @@
-
-
-//! In this example we add a counter resource and increase its value in one system,
-//! while a different system prints the current count to the console.
-
-#![expect(clippy::std_instead_of_core)]
-
-use bevy_ecs::prelude::*;
-use bevy_ecs::world::OnMutate;
-use bevy_reflect::Reflect;
-
-fn main() {
-    let mut world = World::new();
-
-    world.add_observer(ob);
-
-    let mut schedule = Schedule::default();
-
-    schedule
-        .add_systems(
-            (
-                first,
-                second,
-            )
-                .chain()
-        );
-
-    schedule.run(&mut world);
-
-    println!("{:?}", world);
-}
-
-#[derive(Reflect, Default, Component, Debug)]
-struct Count(usize);
-
-fn first(mut commands: Commands) {
-    commands.spawn(Count(0));
-}
-
-fn second(mut counts: Query<Mut<Count>>) {
-    counts.iter_mut().for_each(|mut count| {
-        count.0 += 1;
-    })
-}
-
-fn ob(
-    trigger: Trigger<OnMutate, Count>,
-    counts:  Query<&Count>,
-) {
-    let Ok(count) = counts.get(trigger.entity()) else {
-        return;
-    };
-    dbg!(count);
-}
\ No newline at end of file
diff --git a/crates/bevy_ecs/src/storage/entity_change.rs b/crates/bevy_ecs/src/storage/entity_change.rs
index e6a8cc9d762bbb..98efcba1d9cc7e 100644
--- a/crates/bevy_ecs/src/storage/entity_change.rs
+++ b/crates/bevy_ecs/src/storage/entity_change.rs
@@ -52,4 +52,29 @@ impl EntityChange {
     pub fn component(&self) -> ComponentId {
         self.component
     }
+}
+
+mod tests {
+    #![allow(unused_imports)]
+    use crate::component::ComponentId;
+    use crate::entity::Entity;
+    use crate::storage::{Changes, EntityChange};
+
+    #[test]
+    fn changes() {
+        let mut storage = Changes::new();
+        let entity = Entity::PLACEHOLDER;
+        let component = ComponentId::new(1);
+        storage.push(EntityChange::new(entity, component));
+        storage.push(EntityChange::new(entity, component));
+
+        let changes = storage.take_all();
+        assert_eq!(changes.len(), 2);
+        assert_eq!(storage.take_all().len(), 0);
+
+        changes.iter().for_each(|change| {
+            assert_eq!(change.component, component);
+            assert_eq!(change.entity, entity);
+        })
+    }
 }
\ No newline at end of file
diff --git a/crates/bevy_ecs/src/world/mod.rs b/crates/bevy_ecs/src/world/mod.rs
index 511610533ed9da..1f33b9a2773e34 100644
--- a/crates/bevy_ecs/src/world/mod.rs
+++ b/crates/bevy_ecs/src/world/mod.rs
@@ -63,7 +63,6 @@ use bevy_ptr::UnsafeCellDeref;
 
 use core::panic::Location;
 use unsafe_world_cell::{UnsafeEntityCell, UnsafeWorldCell};
-use crate::storage::Changes;
 
 /// A [`World`] mutation.
 ///
@@ -136,14 +135,6 @@ pub struct World {
     pub(crate) command_queue: RawCommandQueue,
 }
 
-impl World {
-
-    /// Just For Test
-    pub fn test(&mut self) -> &mut Changes {
-        &mut self.storages.changes
-    }
-}
-
 impl Default for World {
     fn default() -> Self {
         let mut world = Self {