Add set_relation_filter method to Query

Author: BoxyUwU

crates/bevy_ecs/src/query/state.rs

@@ -35,8 +35,6 @@ where
     pub(crate) archetype_component_access: Access<ArchetypeComponentId>,
     pub(crate) component_access: FilteredAccess<RelationKindId>,
 
-    // FIXME(Relationships) We need to clear this on `Query` drop impl so that filters dont
-    // persist across system executions
     pub(crate) current_relation_filter: QueryRelationFilter<Q, F>,
     pub(crate) relation_filter_accesses: HashMap<QueryRelationFilter<Q, F>, QueryAccessCache>,
 

crates/bevy_ecs/src/system/query.rs

@@ -1,6 +1,7 @@
 use crate::{
     component::Component,
     entity::Entity,
+    prelude::QueryRelationFilter,
     query::{
         Fetch, FilterFetch, QueryEntityError, QueryIter, QueryState, ReadOnlyFetch, WorldQuery,
     },
@@ -214,6 +215,8 @@ where
             .get_unchecked_manual(self.world, entity, self.last_change_tick, self.change_tick)
     }
 
+    // FIXME(Relationships) we likely want get_relation methods for both `T *` and `T some_entity`
+
     /// Gets a reference to the entity's component of the given type. This will fail if the entity
     /// does not have the given component type or if the given component type does not match
     /// this query.
@@ -352,6 +355,19 @@ where
             >())),
         }
     }
+
+    pub fn set_relation_filter(&mut self, relation_filter: QueryRelationFilter<Q, F>) {
+        self.state.set_relation_filter(&self.world, relation_filter);
+    }
+}
+
+impl<'w, Q: WorldQuery, F: WorldQuery> Drop for Query<'w, Q, F>
+where
+    F::Fetch: FilterFetch,
+{
+    fn drop(&mut self) {
+        self.set_relation_filter(QueryRelationFilter::new());
+    }
 }
 
 /// An error that occurs when retrieving a specific [Entity]'s component from a [Query]

crates/bevy_scene/src/dynamic_scene.rs

@@ -38,7 +38,6 @@ impl DynamicScene {
 
             for (kind_id, _) in archetype.components() {
                 let kind_info = world.components().get_relation_kind(kind_id);
-                // FIXME(Relationships) getting the TypeId here looks suspicious :thinking:
                 let reflect_component = type_registry
                     .get(kind_info.data_layout().type_id().unwrap())
                     .and_then(|registration| registration.data::<ReflectComponent>());