From 3869a4f07ab65bd4daf23c7cc1c0d89261f64e98 Mon Sep 17 00:00:00 2001
From: harudagondi <giogdeasis@gmail.com>
Date: Wed, 13 Jul 2022 15:37:27 +0000
Subject: [PATCH] Allow iter combinations on custom world queries (#5286)

# Objective

- `.iter_combinations_*()` cannot be used on custom derived `WorldQuery`, so this fixes that
- Fixes #5284

## Solution

- `#[derive(Clone)]` on the `Fetch` of the proc macro derive.
- `#[derive(Clone)]` for `AnyOf` to satisfy tests.
---
 crates/bevy_ecs/macros/src/fetch.rs |  1 +
 crates/bevy_ecs/src/query/fetch.rs  |  1 +
 crates/bevy_ecs/src/query/mod.rs    | 20 ++++++++++++++++++++
 3 files changed, 22 insertions(+)

diff --git a/crates/bevy_ecs/macros/src/fetch.rs b/crates/bevy_ecs/macros/src/fetch.rs
index 0b44e3c33c2ae..624cae137ab2a 100644
--- a/crates/bevy_ecs/macros/src/fetch.rs
+++ b/crates/bevy_ecs/macros/src/fetch.rs
@@ -177,6 +177,7 @@ pub fn derive_world_query_impl(ast: DeriveInput) -> TokenStream {
                 #(#(#ignored_field_attrs)* #ignored_field_visibilities #ignored_field_idents: #ignored_field_types,)*
             }
 
+            #[derive(Clone)]
             #[doc(hidden)]
             #visibility struct #fetch_struct_name #user_impl_generics_with_world #user_where_clauses_with_world {
                 #(#field_idents: #path::query::#fetch_type_alias::<'__w, #field_types>,)*
diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
index eb40c1667f0a4..56c8adb53aa5b 100644
--- a/crates/bevy_ecs/src/query/fetch.rs
+++ b/crates/bevy_ecs/src/query/fetch.rs
@@ -1458,6 +1458,7 @@ macro_rules! impl_tuple_fetch {
 /// `Query<AnyOf<(&A, &B, &mut C)>>` is equivalent to `Query<(Option<&A>, Option<&B>, Option<&mut C>), (Or(With<A>, With<B>, With<C>)>`.
 /// Each of the components in `T` is returned as an `Option`, as with `Option<A>` queries.
 /// Entities are guaranteed to have at least one of the components in `T`.
+#[derive(Clone)]
 pub struct AnyOf<T>(T);
 
 macro_rules! impl_anytuple_fetch {
diff --git a/crates/bevy_ecs/src/query/mod.rs b/crates/bevy_ecs/src/query/mod.rs
index 74de0fd802bee..0b260a1a80b65 100644
--- a/crates/bevy_ecs/src/query/mod.rs
+++ b/crates/bevy_ecs/src/query/mod.rs
@@ -657,6 +657,26 @@ mod tests {
                 .collect::<Vec<_>>();
             assert_eq!(custom_param_entities, normal_entities);
         }
+
+        {
+            #[derive(WorldQuery)]
+            struct IterCombAB {
+                a: &'static A,
+                b: &'static B,
+            }
+
+            let custom_param_data = world
+                .query::<IterCombAB>()
+                .iter_combinations::<2>(&world)
+                .map(|[item0, item1]| [(*item0.a, *item0.b), (*item1.a, *item1.b)])
+                .collect::<Vec<_>>();
+            let normal_data = world
+                .query::<(&A, &B)>()
+                .iter_combinations(&world)
+                .map(|[(a0, b0), (a1, b1)]| [(*a0, *b0), (*a1, *b1)])
+                .collect::<Vec<_>>();
+            assert_eq!(custom_param_data, normal_data);
+        }
     }
 
     #[test]