From eb881a4b7798bb2f9766063e00e7b6aa10d15295 Mon Sep 17 00:00:00 2001
From: Chris Russell <8494645+chescock@users.noreply.github.com>
Date: Mon, 14 Jul 2025 20:19:33 -0400
Subject: [PATCH] Add unit test that would have failed before the `init_state`
 changes.

---
 crates/bevy_ecs/src/world/entity_ref.rs | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/crates/bevy_ecs/src/world/entity_ref.rs b/crates/bevy_ecs/src/world/entity_ref.rs
index 0b850f816b..e2977c814d 100644
--- a/crates/bevy_ecs/src/world/entity_ref.rs
+++ b/crates/bevy_ecs/src/world/entity_ref.rs
@@ -5374,6 +5374,19 @@ mod tests {
         }
     }
 
+    #[test]
+    fn entity_mut_except_registers_components() {
+        // Checks for a bug where `EntityMutExcept` would not register the component and
+        // would therefore not include an exception, causing it to conflict with the later query.
+        fn system1(_query: Query<EntityMutExcept<TestComponent>>, _: Query<&mut TestComponent>) {}
+        let mut world = World::new();
+        world.run_system_once(system1).unwrap();
+
+        fn system2(_: Query<&mut TestComponent>, _query: Query<EntityMutExcept<TestComponent>>) {}
+        let mut world = World::new();
+        world.run_system_once(system2).unwrap();
+    }
+
     #[derive(Component)]
     struct A;