From 7bf80dd5984dc48b1b232400ceddfc024456170f Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 13:23:07 +0200
Subject: [PATCH 01/20] documentation for variadics

---
 crates/bevy_ecs/src/lib.rs                    |  3 ++
 crates/bevy_ecs/src/system/builder.rs         | 13 ++++++-
 .../src/system/exclusive_function_system.rs   |  2 +-
 crates/bevy_ecs/src/system/function_system.rs | 22 +++++++++--
 crates/bevy_ecs/src/system/observer_system.rs | 37 +++++++++++++++++++
 crates/bevy_reflect/src/func/info.rs          | 12 +++++-
 crates/bevy_reflect/src/func/reflect_fn.rs    | 12 +++++-
 .../bevy_reflect/src/func/reflect_fn_mut.rs   | 12 +++++-
 crates/bevy_reflect/src/tuple.rs              | 24 ++++++++++--
 9 files changed, 121 insertions(+), 16 deletions(-)

diff --git a/crates/bevy_ecs/src/lib.rs b/crates/bevy_ecs/src/lib.rs
index 69dfea19f5bda..5b0ea69cb88be 100644
--- a/crates/bevy_ecs/src/lib.rs
+++ b/crates/bevy_ecs/src/lib.rs
@@ -9,6 +9,9 @@
     html_logo_url = "https://bevyengine.org/assets/icon.png",
     html_favicon_url = "https://bevyengine.org/assets/icon.png"
 )]
+// `rustdoc_internals` is needed for `#[doc(fake_variadics)]`
+#![allow(internal_features)]
+#![cfg_attr(any(docsrs, docsrs_dep), feature(rustdoc_internals))]
 
 #[cfg(target_pointer_width = "16")]
 compile_error!("bevy_ecs cannot safely compile for a 16-bit platform.");
diff --git a/crates/bevy_ecs/src/system/builder.rs b/crates/bevy_ecs/src/system/builder.rs
index 279cc41381af5..27956eb1e27d6 100644
--- a/crates/bevy_ecs/src/system/builder.rs
+++ b/crates/bevy_ecs/src/system/builder.rs
@@ -233,7 +233,8 @@ unsafe impl<P: SystemParam, B: SystemParamBuilder<P>> SystemParamBuilder<Vec<P>>
 pub struct ParamSetBuilder<T>(pub T);
 
 macro_rules! impl_param_set_builder_tuple {
-    ($(($param: ident, $builder: ident, $meta: ident)),*) => {
+        ($(#[$meta2:meta])* $(($param: ident, $builder: ident, $meta: ident)),*) => {
+        $(#[$meta2])*
         // SAFETY: implementors of each `SystemParamBuilder` in the tuple have validated their impls
         unsafe impl<'w, 's, $($param: SystemParam,)* $($builder: SystemParamBuilder<$param>,)*> SystemParamBuilder<ParamSet<'w, 's, ($($param,)*)>> for ParamSetBuilder<($($builder,)*)> {
             #[allow(non_snake_case)]
@@ -267,7 +268,15 @@ macro_rules! impl_param_set_builder_tuple {
     };
 }
 
-all_tuples!(impl_param_set_builder_tuple, 1, 8, P, B, meta);
+all_tuples!(
+    #[doc(fake_variadic)]
+    impl_param_set_builder_tuple,
+    1,
+    8,
+    P,
+    B,
+    meta
+);
 
 // SAFETY: Relevant parameter ComponentId and ArchetypeComponentId access is applied to SystemMeta. If any ParamState conflicts
 // with any prior access, a panic will occur.
diff --git a/crates/bevy_ecs/src/system/exclusive_function_system.rs b/crates/bevy_ecs/src/system/exclusive_function_system.rs
index 3075f3c55772e..636a8ad928135 100644
--- a/crates/bevy_ecs/src/system/exclusive_function_system.rs
+++ b/crates/bevy_ecs/src/system/exclusive_function_system.rs
@@ -219,7 +219,7 @@ pub struct HasExclusiveSystemInput;
 macro_rules! impl_exclusive_system_function {
     ($($param: ident),*) => {
         #[allow(non_snake_case)]
-        impl<Out, Func, $($param: ExclusiveSystemParam),*> ExclusiveSystemParamFunction<fn($($param,)*) -> Out> for Func
+        impl<Out, Func: Send + Sync + 'static, $($param: ExclusiveSystemParam),*> ExclusiveSystemParamFunction<fn($($param,)*) -> Out> for Func
         where
             Func: Send + Sync + 'static,
             for <'a> &'a mut Func:
diff --git a/crates/bevy_ecs/src/system/function_system.rs b/crates/bevy_ecs/src/system/function_system.rs
index 0614d7339ca4b..2b5653827011f 100644
--- a/crates/bevy_ecs/src/system/function_system.rs
+++ b/crates/bevy_ecs/src/system/function_system.rs
@@ -218,7 +218,8 @@ pub struct SystemState<Param: SystemParam + 'static> {
 // So, generate a function for each arity with an explicit `FnMut` constraint to enable higher-order lifetimes,
 // along with a regular `SystemParamFunction` constraint to allow the system to be built.
 macro_rules! impl_build_system {
-    ($($param: ident),*) => {
+    ($(#[$meta:meta])* $($param: ident),*) => {
+        $(#[$meta])*
         impl<$($param: SystemParam),*> SystemState<($($param,)*)> {
             /// Create a [`FunctionSystem`] from a [`SystemState`].
             /// This method signature allows type inference of closure parameters for a system with no input.
@@ -256,7 +257,13 @@ macro_rules! impl_build_system {
     }
 }
 
-all_tuples!(impl_build_system, 0, 16, P);
+all_tuples!(
+    #[doc(fake_variadic)]
+    impl_build_system,
+    0,
+    16,
+    P
+);
 
 impl<Param: SystemParam> SystemState<Param> {
     /// Creates a new [`SystemState`] with default state.
@@ -809,7 +816,8 @@ pub trait SystemParamFunction<Marker>: Send + Sync + 'static {
 pub struct HasSystemInput;
 
 macro_rules! impl_system_function {
-    ($($param: ident),*) => {
+    ($(#[$meta:meta])* $($param: ident),*) => {
+        $(#[$meta])*
         #[allow(non_snake_case)]
         impl<Out, Func, $($param: SystemParam),*> SystemParamFunction<fn($($param,)*) -> Out> for Func
         where
@@ -871,7 +879,13 @@ macro_rules! impl_system_function {
 
 // Note that we rely on the highest impl to be <= the highest order of the tuple impls
 // of `SystemParam` created.
-all_tuples!(impl_system_function, 0, 16, F);
+all_tuples!(
+    #[doc(fake_variadic)]
+    impl_system_function,
+    0,
+    16,
+    F
+);
 
 #[cfg(test)]
 mod tests {
diff --git a/crates/bevy_ecs/src/system/observer_system.rs b/crates/bevy_ecs/src/system/observer_system.rs
index 55173ccf4f22a..044c0e5901df9 100644
--- a/crates/bevy_ecs/src/system/observer_system.rs
+++ b/crates/bevy_ecs/src/system/observer_system.rs
@@ -51,6 +51,43 @@ where
     }
 }
 
+macro_rules! impl_system_function {
+    ($($param: ident),*) => {
+        #[allow(non_snake_case)]
+        impl<E: 'static, B: Bundle, Out, Func: Send + Sync + 'static, $($param: SystemParam),*> SystemParamFunction<fn(Trigger<E, B>, $($param,)*)> for Func
+        where
+        for <'a> &'a mut Func:
+                FnMut(Trigger<E, B>, $($param),*) -> Out +
+                FnMut(Trigger<E, B>, $(SystemParamItem<$param>),*) -> Out, Out: 'static
+        {
+            type In = Trigger<'static, E, B>;
+            type Out = Out;
+            type Param = ($($param,)*);
+            #[inline]
+            fn run(&mut self, input: Trigger<'static, E, B>, param_value: SystemParamItem< ($($param,)*)>) -> Out {
+                #[allow(clippy::too_many_arguments)]
+                fn call_inner<E: 'static, B: Bundle, Out, $($param,)*>(
+                    mut f: impl FnMut(Trigger<'static, E, B>, $($param,)*) -> Out,
+                    input: Trigger<'static, E, B>,
+                    $($param: $param,)*
+                ) -> Out{
+                    f(input, $($param,)*)
+                }
+                let ($($param,)*) = param_value;
+                call_inner(self, input, $($param),*)
+            }
+        }
+    }
+}
+
+all_tuples!(
+    #[doc(fake_variadic)]
+    impl_system_function,
+    0,
+    16,
+    F
+);
+
 #[cfg(test)]
 mod tests {
     use crate::{
diff --git a/crates/bevy_reflect/src/func/info.rs b/crates/bevy_reflect/src/func/info.rs
index 39accdf52dceb..0a9d6084124e0 100644
--- a/crates/bevy_reflect/src/func/info.rs
+++ b/crates/bevy_reflect/src/func/info.rs
@@ -231,8 +231,9 @@ pub trait TypedFunction<Marker> {
 /// - `FnMut(&mut Receiver, arg0, arg1, ..., argN) -> &mut R`
 /// - `FnMut(&mut Receiver, arg0, arg1, ..., argN) -> &R`
 macro_rules! impl_typed_function {
-    ($(($Arg:ident, $arg:ident)),*) => {
+    ($(#[$meta:meta])* $(($Arg:ident, $arg:ident)),*) => {
         // === (...) -> ReturnType === //
+        $(#[$meta])*
         impl<$($Arg,)* ReturnType, Function> TypedFunction<fn($($Arg),*) -> [ReturnType]> for Function
         where
             $($Arg: TypePath + GetOwnership,)*
@@ -332,7 +333,14 @@ macro_rules! impl_typed_function {
     };
 }
 
-all_tuples!(impl_typed_function, 0, 15, Arg, arg);
+all_tuples!(
+    #[doc(fake_variadic)]
+    impl_typed_function,
+    0,
+    15,
+    Arg,
+    arg
+);
 
 /// Helper function for creating [`FunctionInfo`] with the proper name value.
 ///
diff --git a/crates/bevy_reflect/src/func/reflect_fn.rs b/crates/bevy_reflect/src/func/reflect_fn.rs
index 6e29fd4e075eb..f66a7ce709700 100644
--- a/crates/bevy_reflect/src/func/reflect_fn.rs
+++ b/crates/bevy_reflect/src/func/reflect_fn.rs
@@ -76,8 +76,9 @@ pub trait ReflectFn<'env, Marker>: ReflectFnMut<'env, Marker> {
 /// - `Fn(&mut Receiver, arg0, arg1, ..., argN) -> &mut R`
 /// - `Fn(&mut Receiver, arg0, arg1, ..., argN) -> &R`
 macro_rules! impl_reflect_fn {
-    ($(($Arg:ident, $arg:ident)),*) => {
+    ($(#[$meta:meta])* $(($Arg:ident, $arg:ident)),*) => {
         // === (...) -> ReturnType === //
+        $(#[$meta])*
         impl<'env, $($Arg,)* ReturnType, Function> ReflectFn<'env, fn($($Arg),*) -> [ReturnType]> for Function
         where
             $($Arg: FromArg,)*
@@ -197,4 +198,11 @@ macro_rules! impl_reflect_fn {
     };
 }
 
-all_tuples!(impl_reflect_fn, 0, 15, Arg, arg);
+all_tuples!(
+    #[doc(fake_variadic)]
+    impl_reflect_fn,
+    0,
+    15,
+    Arg,
+    arg
+);
diff --git a/crates/bevy_reflect/src/func/reflect_fn_mut.rs b/crates/bevy_reflect/src/func/reflect_fn_mut.rs
index be73aca79b6bb..008e52f334a64 100644
--- a/crates/bevy_reflect/src/func/reflect_fn_mut.rs
+++ b/crates/bevy_reflect/src/func/reflect_fn_mut.rs
@@ -82,8 +82,9 @@ pub trait ReflectFnMut<'env, Marker> {
 /// - `FnMut(&mut Receiver, arg0, arg1, ..., argN) -> &mut R`
 /// - `FnMut(&mut Receiver, arg0, arg1, ..., argN) -> &R`
 macro_rules! impl_reflect_fn_mut {
-    ($(($Arg:ident, $arg:ident)),*) => {
+    ($(#[$meta:meta])* $(($Arg:ident, $arg:ident)),*) => {
         // === (...) -> ReturnType === //
+        $(#[$meta])*
         impl<'env, $($Arg,)* ReturnType, Function> ReflectFnMut<'env, fn($($Arg),*) -> [ReturnType]> for Function
         where
             $($Arg: FromArg,)*
@@ -203,4 +204,11 @@ macro_rules! impl_reflect_fn_mut {
     };
 }
 
-all_tuples!(impl_reflect_fn_mut, 0, 15, Arg, arg);
+all_tuples!(
+    #[doc(fake_variadic)]
+    impl_reflect_fn_mut,
+    0,
+    15,
+    Arg,
+    arg
+);
diff --git a/crates/bevy_reflect/src/tuple.rs b/crates/bevy_reflect/src/tuple.rs
index 6ec53efa514e4..20df0362fae1e 100644
--- a/crates/bevy_reflect/src/tuple.rs
+++ b/crates/bevy_reflect/src/tuple.rs
@@ -737,7 +737,13 @@ const _: () = {
     };
 }
 
-    all_tuples!(impl_get_ownership_tuple, 0, 12, P);
+    all_tuples!(
+        #[doc(fake_variadic)]
+        impl_get_ownership_tuple,
+        0,
+        12,
+        P
+    );
 
     macro_rules! impl_from_arg_tuple {
     ($($name: ident),*) => {
@@ -745,7 +751,13 @@ const _: () = {
     };
 }
 
-    all_tuples!(impl_from_arg_tuple, 0, 12, P);
+    all_tuples!(
+        #[doc(fake_variadic)]
+        impl_from_arg_tuple,
+        0,
+        12,
+        P
+    );
 
     macro_rules! impl_into_return_tuple {
     ($($name: ident),+) => {
@@ -754,7 +766,13 @@ const _: () = {
 }
 
     // The unit type (i.e. `()`) is special-cased, so we skip implementing it here.
-    all_tuples!(impl_into_return_tuple, 1, 12, P);
+    all_tuples!(
+        #[doc(fake_variadic)]
+        impl_into_return_tuple,
+        1,
+        12,
+        P
+    );
 };
 
 #[cfg(test)]

From 2ca4e15050ef7a9cda97bf29640f640260f319fa Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 13:28:55 +0200
Subject: [PATCH 02/20] fix error

---
 crates/bevy_reflect/src/lib.rs   | 2 +-
 crates/bevy_reflect/src/tuple.rs | 9 ++++++---
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/crates/bevy_reflect/src/lib.rs b/crates/bevy_reflect/src/lib.rs
index 021971a33a68c..f575c345ea425 100644
--- a/crates/bevy_reflect/src/lib.rs
+++ b/crates/bevy_reflect/src/lib.rs
@@ -520,7 +520,7 @@
 //! [the language feature for dyn upcasting coercion]: https://github.com/rust-lang/rust/issues/65991
 //! [derive macro]: derive@crate::Reflect
 //! [`'static` lifetime]: https://doc.rust-lang.org/rust-by-example/scope/lifetime/static_lifetime.html#trait-bound
-//! [`Function`]: func::Function
+//! [`Function`]: crate::func::Function
 //! [derive macro documentation]: derive@crate::Reflect
 //! [deriving `Reflect`]: derive@crate::Reflect
 //! [type data]: TypeData
diff --git a/crates/bevy_reflect/src/tuple.rs b/crates/bevy_reflect/src/tuple.rs
index 20df0362fae1e..e824c323907cf 100644
--- a/crates/bevy_reflect/src/tuple.rs
+++ b/crates/bevy_reflect/src/tuple.rs
@@ -732,7 +732,8 @@ all_tuples!(
 #[cfg(feature = "functions")]
 const _: () = {
     macro_rules! impl_get_ownership_tuple {
-    ($($name: ident),*) => {
+    ($(#[$meta:meta])* $($name: ident),*) => {
+        $(#[$meta])*
         $crate::func::args::impl_get_ownership!(($($name,)*); <$($name),*>);
     };
 }
@@ -746,7 +747,8 @@ const _: () = {
     );
 
     macro_rules! impl_from_arg_tuple {
-    ($($name: ident),*) => {
+    ($(#[$meta:meta])* $($name: ident),*) => {
+        $(#[$meta])*
         $crate::func::args::impl_from_arg!(($($name,)*); <$($name: FromReflect + MaybeTyped + TypePath + GetTypeRegistration),*>);
     };
 }
@@ -760,7 +762,8 @@ const _: () = {
     );
 
     macro_rules! impl_into_return_tuple {
-    ($($name: ident),+) => {
+    ($(#[$meta:meta])* $($name: ident),+) => {
+        $(#[$meta])*
         $crate::func::impl_into_return!(($($name,)*); <$($name: FromReflect + MaybeTyped + TypePath + GetTypeRegistration),*>);
     };
 }

From 6be5d4b26f85d613872bf92af58e3d5d7027e3cd Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 13:35:27 +0200
Subject: [PATCH 03/20] fix error

---
 crates/bevy_ecs/src/lib.rs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/crates/bevy_ecs/src/lib.rs b/crates/bevy_ecs/src/lib.rs
index 5b0ea69cb88be..69dfea19f5bda 100644
--- a/crates/bevy_ecs/src/lib.rs
+++ b/crates/bevy_ecs/src/lib.rs
@@ -9,9 +9,6 @@
     html_logo_url = "https://bevyengine.org/assets/icon.png",
     html_favicon_url = "https://bevyengine.org/assets/icon.png"
 )]
-// `rustdoc_internals` is needed for `#[doc(fake_variadics)]`
-#![allow(internal_features)]
-#![cfg_attr(any(docsrs, docsrs_dep), feature(rustdoc_internals))]
 
 #[cfg(target_pointer_width = "16")]
 compile_error!("bevy_ecs cannot safely compile for a 16-bit platform.");

From b86eba7b506d143e5805d5dc8d70e4e7f457bd78 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 19:24:50 +0200
Subject: [PATCH 04/20] wip

---
 crates/bevy_app/src/plugin.rs      | 12 +++++++++--
 crates/bevy_ecs/src/query/fetch.rs | 12 +++++++++--
 crates/bevy_reflect/src/tuple.rs   | 34 ++++++++++++++++++------------
 3 files changed, 40 insertions(+), 18 deletions(-)

diff --git a/crates/bevy_app/src/plugin.rs b/crates/bevy_app/src/plugin.rs
index 0659c6a311884..c264264695c63 100644
--- a/crates/bevy_app/src/plugin.rs
+++ b/crates/bevy_app/src/plugin.rs
@@ -162,7 +162,8 @@ mod sealed {
     }
 
     macro_rules! impl_plugins_tuples {
-        ($(($param: ident, $plugins: ident)),*) => {
+        ($(#[$meta:meta])* $(($param: ident, $plugins: ident)),*) => {
+            $(#[$meta])*
             impl<$($param, $plugins),*> Plugins<(PluginsTupleMarker, $($param,)*)> for ($($plugins,)*)
             where
                 $($plugins: Plugins<$param>),*
@@ -179,5 +180,12 @@ mod sealed {
         }
     }
 
-    all_tuples!(impl_plugins_tuples, 0, 15, P, S);
+    all_tuples!(
+        #[doc(fake_variadic)]
+        impl_plugins_tuples,
+        0,
+        15,
+        P,
+        S
+    );
 }
diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
index e2140a36912ff..8cb0a0b96d8ec 100644
--- a/crates/bevy_ecs/src/query/fetch.rs
+++ b/crates/bevy_ecs/src/query/fetch.rs
@@ -2025,7 +2025,7 @@ macro_rules! impl_tuple_query_data {
 }
 
 macro_rules! impl_anytuple_fetch {
-    ($(($name: ident, $state: ident)),*) => {
+    ($(#[$meta:meta])* $(($name: ident, $state: ident)),*) => {
 
         #[allow(non_snake_case)]
         #[allow(clippy::unused_unit)]
@@ -2034,6 +2034,7 @@ macro_rules! impl_anytuple_fetch {
         /// This is sound because `update_component_access` and `update_archetype_component_access` adds accesses according to the implementations of all the subqueries.
         /// `update_component_access` replaces the filters with a disjunction where every element is a conjunction of the previous filters and the filters of one of the subqueries.
         /// This is sound because `matches_component_set` returns a disjunction of the results of the subqueries' implementations.
+        $(#[$meta])*
         unsafe impl<$($name: WorldQuery),*> WorldQuery for AnyOf<($($name,)*)> {
             type Fetch<'w> = ($(($name::Fetch<'w>, bool),)*);
             type Item<'w> = ($(Option<$name::Item<'w>>,)*);
@@ -2168,7 +2169,14 @@ all_tuples!(
     F,
     S
 );
-all_tuples!(impl_anytuple_fetch, 0, 15, F, S);
+all_tuples!(
+    #[doc(fake_variadic)]
+    impl_anytuple_fetch,
+    0,
+    15,
+    F,
+    S
+);
 
 /// [`WorldQuery`] used to nullify queries by turning `Query<D>` into `Query<NopWorldQuery<D>>`
 ///
diff --git a/crates/bevy_reflect/src/tuple.rs b/crates/bevy_reflect/src/tuple.rs
index e824c323907cf..1994ad06b9c77 100644
--- a/crates/bevy_reflect/src/tuple.rs
+++ b/crates/bevy_reflect/src/tuple.rs
@@ -469,7 +469,8 @@ pub fn tuple_debug(dyn_tuple: &dyn Tuple, f: &mut Formatter<'_>) -> core::fmt::R
 }
 
 macro_rules! impl_reflect_tuple {
-    {$($index:tt : $name:tt),*} => {
+    {$(#[$meta:meta])* $($index:tt : $name:tt),*} => {
+        $(#[$meta])*
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> Tuple for ($($name,)*) {
             #[inline]
             fn field(&self, index: usize) -> Option<&dyn PartialReflect> {
@@ -521,6 +522,7 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
+        $(#[$meta])*
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> PartialReflect for ($($name,)*) {
             fn get_represented_type_info(&self) -> Option<&'static TypeInfo> {
                 Some(<Self as Typed>::type_info())
@@ -584,6 +586,7 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
+        $(#[$meta])*
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> Reflect for ($($name,)*) {
             fn into_any(self: Box<Self>) -> Box<dyn Any> {
                 self
@@ -615,6 +618,7 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
+        $(#[$meta])*
         impl <$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> Typed for ($($name,)*) {
             fn type_info() -> &'static TypeInfo {
                 static CELL: $crate::utility::GenericTypeInfoCell = $crate::utility::GenericTypeInfoCell::new();
@@ -628,6 +632,7 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
+        $(#[$meta])*
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> GetTypeRegistration for ($($name,)*) {
             fn get_type_registration() -> TypeRegistration {
                 TypeRegistration::of::<($($name,)*)>()
@@ -638,6 +643,7 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
+        $(#[$meta])*
         impl<$($name: FromReflect + MaybeTyped + TypePath + GetTypeRegistration),*> FromReflect for ($($name,)*)
         {
             fn from_reflect(reflect: &dyn PartialReflect) -> Option<Self> {
@@ -655,19 +661,19 @@ macro_rules! impl_reflect_tuple {
     }
 }
 
-impl_reflect_tuple! {}
-impl_reflect_tuple! {0: A}
-impl_reflect_tuple! {0: A, 1: B}
-impl_reflect_tuple! {0: A, 1: B, 2: C}
-impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D}
-impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E}
-impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F}
-impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G}
-impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H}
-impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I}
-impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J}
-impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K}
-impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K, 11: L}
+impl_reflect_tuple! {#[doc(fake_variadic)]}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K}
+impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K, 11: L}
 
 macro_rules! impl_type_path_tuple {
     ($(#[$meta:meta])*) => {

From 194db24896b160ddccaca9839b581f88804b4df7 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 19:25:52 +0200
Subject: [PATCH 05/20] undo

---
 crates/bevy_reflect/src/func/info.rs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/crates/bevy_reflect/src/func/info.rs b/crates/bevy_reflect/src/func/info.rs
index 0a9d6084124e0..404053ee0c7fc 100644
--- a/crates/bevy_reflect/src/func/info.rs
+++ b/crates/bevy_reflect/src/func/info.rs
@@ -231,9 +231,8 @@ pub trait TypedFunction<Marker> {
 /// - `FnMut(&mut Receiver, arg0, arg1, ..., argN) -> &mut R`
 /// - `FnMut(&mut Receiver, arg0, arg1, ..., argN) -> &R`
 macro_rules! impl_typed_function {
-    ($(#[$meta:meta])* $(($Arg:ident, $arg:ident)),*) => {
+    ($(($Arg:ident, $arg:ident)),*) => {
         // === (...) -> ReturnType === //
-        $(#[$meta])*
         impl<$($Arg,)* ReturnType, Function> TypedFunction<fn($($Arg),*) -> [ReturnType]> for Function
         where
             $($Arg: TypePath + GetOwnership,)*
@@ -334,7 +333,6 @@ macro_rules! impl_typed_function {
 }
 
 all_tuples!(
-    #[doc(fake_variadic)]
     impl_typed_function,
     0,
     15,

From 737cd0894f7686230cdcf5c5f43e23065db3c5e2 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 19:26:11 +0200
Subject: [PATCH 06/20] fmt

---
 crates/bevy_reflect/src/func/info.rs | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/crates/bevy_reflect/src/func/info.rs b/crates/bevy_reflect/src/func/info.rs
index 404053ee0c7fc..39accdf52dceb 100644
--- a/crates/bevy_reflect/src/func/info.rs
+++ b/crates/bevy_reflect/src/func/info.rs
@@ -332,13 +332,7 @@ macro_rules! impl_typed_function {
     };
 }
 
-all_tuples!(
-    impl_typed_function,
-    0,
-    15,
-    Arg,
-    arg
-);
+all_tuples!(impl_typed_function, 0, 15, Arg, arg);
 
 /// Helper function for creating [`FunctionInfo`] with the proper name value.
 ///

From 3da56be4902b1805df29c5d3fed3cb08aeb4295b Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 21:09:24 +0200
Subject: [PATCH 07/20] temp

---
 crates/bevy_reflect/src/tuple.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/bevy_reflect/src/tuple.rs b/crates/bevy_reflect/src/tuple.rs
index 1994ad06b9c77..a32190dfc307e 100644
--- a/crates/bevy_reflect/src/tuple.rs
+++ b/crates/bevy_reflect/src/tuple.rs
@@ -469,7 +469,7 @@ pub fn tuple_debug(dyn_tuple: &dyn Tuple, f: &mut Formatter<'_>) -> core::fmt::R
 }
 
 macro_rules! impl_reflect_tuple {
-    {$(#[$meta:meta])* $($index:tt : $name:tt),*} => {
+    {$(#[$meta:meta]) $($index:tt : $name:tt),*} => {
         $(#[$meta])*
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> Tuple for ($($name,)*) {
             #[inline]

From 1cc17aa0f743443eefdd6e82c09d5f39c88e0c3b Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 21:30:15 +0200
Subject: [PATCH 08/20] wip

---
 crates/bevy_reflect/src/tuple.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/bevy_reflect/src/tuple.rs b/crates/bevy_reflect/src/tuple.rs
index a32190dfc307e..cbd4d5af25d1c 100644
--- a/crates/bevy_reflect/src/tuple.rs
+++ b/crates/bevy_reflect/src/tuple.rs
@@ -469,7 +469,7 @@ pub fn tuple_debug(dyn_tuple: &dyn Tuple, f: &mut Formatter<'_>) -> core::fmt::R
 }
 
 macro_rules! impl_reflect_tuple {
-    {$(#[$meta:meta]) $($index:tt : $name:tt),*} => {
+    {$(#[$meta:meta])+ $($index:tt : $name:tt),*} => {
         $(#[$meta])*
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> Tuple for ($($name,)*) {
             #[inline]

From f011ed94bf6813789f5b3896acfce56cdffe34dd Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 23:04:05 +0200
Subject: [PATCH 09/20] cleanup

---
 crates/bevy_reflect/src/tuple.rs | 34 +++++++++++++-------------------
 1 file changed, 14 insertions(+), 20 deletions(-)

diff --git a/crates/bevy_reflect/src/tuple.rs b/crates/bevy_reflect/src/tuple.rs
index cbd4d5af25d1c..02be82faa18ab 100644
--- a/crates/bevy_reflect/src/tuple.rs
+++ b/crates/bevy_reflect/src/tuple.rs
@@ -469,8 +469,7 @@ pub fn tuple_debug(dyn_tuple: &dyn Tuple, f: &mut Formatter<'_>) -> core::fmt::R
 }
 
 macro_rules! impl_reflect_tuple {
-    {$(#[$meta:meta])+ $($index:tt : $name:tt),*} => {
-        $(#[$meta])*
+    {$($index:tt : $name:tt),*} => {
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> Tuple for ($($name,)*) {
             #[inline]
             fn field(&self, index: usize) -> Option<&dyn PartialReflect> {
@@ -522,7 +521,6 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
-        $(#[$meta])*
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> PartialReflect for ($($name,)*) {
             fn get_represented_type_info(&self) -> Option<&'static TypeInfo> {
                 Some(<Self as Typed>::type_info())
@@ -586,7 +584,6 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
-        $(#[$meta])*
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> Reflect for ($($name,)*) {
             fn into_any(self: Box<Self>) -> Box<dyn Any> {
                 self
@@ -618,7 +615,6 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
-        $(#[$meta])*
         impl <$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> Typed for ($($name,)*) {
             fn type_info() -> &'static TypeInfo {
                 static CELL: $crate::utility::GenericTypeInfoCell = $crate::utility::GenericTypeInfoCell::new();
@@ -632,7 +628,6 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
-        $(#[$meta])*
         impl<$($name: Reflect + MaybeTyped + TypePath + GetTypeRegistration),*> GetTypeRegistration for ($($name,)*) {
             fn get_type_registration() -> TypeRegistration {
                 TypeRegistration::of::<($($name,)*)>()
@@ -643,7 +638,6 @@ macro_rules! impl_reflect_tuple {
             }
         }
 
-        $(#[$meta])*
         impl<$($name: FromReflect + MaybeTyped + TypePath + GetTypeRegistration),*> FromReflect for ($($name,)*)
         {
             fn from_reflect(reflect: &dyn PartialReflect) -> Option<Self> {
@@ -661,19 +655,19 @@ macro_rules! impl_reflect_tuple {
     }
 }
 
-impl_reflect_tuple! {#[doc(fake_variadic)]}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K}
-impl_reflect_tuple! {#[doc(fake_variadic)] 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K, 11: L}
+impl_reflect_tuple! {}
+impl_reflect_tuple! { 0: A}
+impl_reflect_tuple! { 0: A, 1: B}
+impl_reflect_tuple! { 0: A, 1: B, 2: C}
+impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D}
+impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E}
+impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F}
+impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G}
+impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H}
+impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I}
+impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J}
+impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K}
+impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K, 11: L}
 
 macro_rules! impl_type_path_tuple {
     ($(#[$meta:meta])*) => {

From 1e6fb99a09ba4e7e839b7d1dd8981be42e219ef2 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Mon, 23 Sep 2024 23:12:57 +0200
Subject: [PATCH 10/20] fix

---
 crates/bevy_ecs/src/query/fetch.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
index 8cb0a0b96d8ec..b8f54203111ba 100644
--- a/crates/bevy_ecs/src/query/fetch.rs
+++ b/crates/bevy_ecs/src/query/fetch.rs
@@ -2029,12 +2029,12 @@ macro_rules! impl_anytuple_fetch {
 
         #[allow(non_snake_case)]
         #[allow(clippy::unused_unit)]
+        $(#[$meta])*
         /// SAFETY:
         /// `fetch` accesses are a subset of the subqueries' accesses
         /// This is sound because `update_component_access` and `update_archetype_component_access` adds accesses according to the implementations of all the subqueries.
         /// `update_component_access` replaces the filters with a disjunction where every element is a conjunction of the previous filters and the filters of one of the subqueries.
         /// This is sound because `matches_component_set` returns a disjunction of the results of the subqueries' implementations.
-        $(#[$meta])*
         unsafe impl<$($name: WorldQuery),*> WorldQuery for AnyOf<($($name,)*)> {
             type Fetch<'w> = ($(($name::Fetch<'w>, bool),)*);
             type Item<'w> = ($(Option<$name::Item<'w>>,)*);

From 4405f16b09196d2981bc405b140d76abb928bd31 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Wed, 25 Sep 2024 10:21:51 +0200
Subject: [PATCH 11/20] add unused meta

---
 crates/bevy_ecs/src/system/exclusive_function_system.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/bevy_ecs/src/system/exclusive_function_system.rs b/crates/bevy_ecs/src/system/exclusive_function_system.rs
index 636a8ad928135..3075f3c55772e 100644
--- a/crates/bevy_ecs/src/system/exclusive_function_system.rs
+++ b/crates/bevy_ecs/src/system/exclusive_function_system.rs
@@ -219,7 +219,7 @@ pub struct HasExclusiveSystemInput;
 macro_rules! impl_exclusive_system_function {
     ($($param: ident),*) => {
         #[allow(non_snake_case)]
-        impl<Out, Func: Send + Sync + 'static, $($param: ExclusiveSystemParam),*> ExclusiveSystemParamFunction<fn($($param,)*) -> Out> for Func
+        impl<Out, Func, $($param: ExclusiveSystemParam),*> ExclusiveSystemParamFunction<fn($($param,)*) -> Out> for Func
         where
             Func: Send + Sync + 'static,
             for <'a> &'a mut Func:

From 819bcf1683a6ca83278b43bfd6b421e196d03691 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Wed, 25 Sep 2024 15:05:36 +0200
Subject: [PATCH 12/20] doc errors

---
 crates/bevy_app/src/lib.rs                    |  3 +++
 crates/bevy_ecs/src/query/fetch.rs            | 24 ++++---------------
 crates/bevy_ecs/src/system/builder.rs         | 13 ++--------
 crates/bevy_ecs/src/system/function_system.rs | 22 ++++-------------
 4 files changed, 13 insertions(+), 49 deletions(-)

diff --git a/crates/bevy_app/src/lib.rs b/crates/bevy_app/src/lib.rs
index 830772803bec0..bcbd0afd9bc58 100644
--- a/crates/bevy_app/src/lib.rs
+++ b/crates/bevy_app/src/lib.rs
@@ -1,4 +1,7 @@
 #![cfg_attr(docsrs, feature(doc_auto_cfg))]
+// `rustdoc_internals` is needed for `#[doc(fake_variadics)]`
+#![allow(internal_features)]
+#![cfg_attr(any(docsrs, docsrs_dep), feature(doc_auto_cfg, rustdoc_internals))]
 #![forbid(unsafe_code)]
 #![doc(
     html_logo_url = "https://bevyengine.org/assets/icon.png",
diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
index b8f54203111ba..c9ca4adf0194e 100644
--- a/crates/bevy_ecs/src/query/fetch.rs
+++ b/crates/bevy_ecs/src/query/fetch.rs
@@ -2008,11 +2008,10 @@ unsafe impl<T: Component> ReadOnlyQueryData for Has<T> {}
 pub struct AnyOf<T>(PhantomData<T>);
 
 macro_rules! impl_tuple_query_data {
-    ($(#[$meta:meta])* $(($name: ident, $state: ident)),*) => {
+    ($(($name: ident, $state: ident)),*) => {
 
         #[allow(non_snake_case)]
         #[allow(clippy::unused_unit)]
-        $(#[$meta])*
         // SAFETY: defers to soundness `$name: WorldQuery` impl
         unsafe impl<$($name: QueryData),*> QueryData for ($($name,)*) {
             type ReadOnly = ($($name::ReadOnly,)*);
@@ -2025,11 +2024,10 @@ macro_rules! impl_tuple_query_data {
 }
 
 macro_rules! impl_anytuple_fetch {
-    ($(#[$meta:meta])* $(($name: ident, $state: ident)),*) => {
+    ($(($name: ident, $state: ident)),*) => {
 
         #[allow(non_snake_case)]
         #[allow(clippy::unused_unit)]
-        $(#[$meta])*
         /// SAFETY:
         /// `fetch` accesses are a subset of the subqueries' accesses
         /// This is sound because `update_component_access` and `update_archetype_component_access` adds accesses according to the implementations of all the subqueries.
@@ -2161,22 +2159,8 @@ macro_rules! impl_anytuple_fetch {
     };
 }
 
-all_tuples!(
-    #[doc(fake_variadic)]
-    impl_tuple_query_data,
-    0,
-    15,
-    F,
-    S
-);
-all_tuples!(
-    #[doc(fake_variadic)]
-    impl_anytuple_fetch,
-    0,
-    15,
-    F,
-    S
-);
+all_tuples!(impl_tuple_query_data, 0, 15, F, S);
+all_tuples!(impl_anytuple_fetch, 0, 15, F, S);
 
 /// [`WorldQuery`] used to nullify queries by turning `Query<D>` into `Query<NopWorldQuery<D>>`
 ///
diff --git a/crates/bevy_ecs/src/system/builder.rs b/crates/bevy_ecs/src/system/builder.rs
index 27956eb1e27d6..21f1756ce8852 100644
--- a/crates/bevy_ecs/src/system/builder.rs
+++ b/crates/bevy_ecs/src/system/builder.rs
@@ -233,8 +233,7 @@ unsafe impl<P: SystemParam, B: SystemParamBuilder<P>> SystemParamBuilder<Vec<P>>
 pub struct ParamSetBuilder<T>(pub T);
 
 macro_rules! impl_param_set_builder_tuple {
-        ($(#[$meta2:meta])* $(($param: ident, $builder: ident, $meta: ident)),*) => {
-        $(#[$meta2])*
+        ($(($param: ident, $builder: ident, $meta: ident)),*) => {
         // SAFETY: implementors of each `SystemParamBuilder` in the tuple have validated their impls
         unsafe impl<'w, 's, $($param: SystemParam,)* $($builder: SystemParamBuilder<$param>,)*> SystemParamBuilder<ParamSet<'w, 's, ($($param,)*)>> for ParamSetBuilder<($($builder,)*)> {
             #[allow(non_snake_case)]
@@ -268,15 +267,7 @@ macro_rules! impl_param_set_builder_tuple {
     };
 }
 
-all_tuples!(
-    #[doc(fake_variadic)]
-    impl_param_set_builder_tuple,
-    1,
-    8,
-    P,
-    B,
-    meta
-);
+all_tuples!(impl_param_set_builder_tuple, 1, 8, P, B, meta);
 
 // SAFETY: Relevant parameter ComponentId and ArchetypeComponentId access is applied to SystemMeta. If any ParamState conflicts
 // with any prior access, a panic will occur.
diff --git a/crates/bevy_ecs/src/system/function_system.rs b/crates/bevy_ecs/src/system/function_system.rs
index 2b5653827011f..0614d7339ca4b 100644
--- a/crates/bevy_ecs/src/system/function_system.rs
+++ b/crates/bevy_ecs/src/system/function_system.rs
@@ -218,8 +218,7 @@ pub struct SystemState<Param: SystemParam + 'static> {
 // So, generate a function for each arity with an explicit `FnMut` constraint to enable higher-order lifetimes,
 // along with a regular `SystemParamFunction` constraint to allow the system to be built.
 macro_rules! impl_build_system {
-    ($(#[$meta:meta])* $($param: ident),*) => {
-        $(#[$meta])*
+    ($($param: ident),*) => {
         impl<$($param: SystemParam),*> SystemState<($($param,)*)> {
             /// Create a [`FunctionSystem`] from a [`SystemState`].
             /// This method signature allows type inference of closure parameters for a system with no input.
@@ -257,13 +256,7 @@ macro_rules! impl_build_system {
     }
 }
 
-all_tuples!(
-    #[doc(fake_variadic)]
-    impl_build_system,
-    0,
-    16,
-    P
-);
+all_tuples!(impl_build_system, 0, 16, P);
 
 impl<Param: SystemParam> SystemState<Param> {
     /// Creates a new [`SystemState`] with default state.
@@ -816,8 +809,7 @@ pub trait SystemParamFunction<Marker>: Send + Sync + 'static {
 pub struct HasSystemInput;
 
 macro_rules! impl_system_function {
-    ($(#[$meta:meta])* $($param: ident),*) => {
-        $(#[$meta])*
+    ($($param: ident),*) => {
         #[allow(non_snake_case)]
         impl<Out, Func, $($param: SystemParam),*> SystemParamFunction<fn($($param,)*) -> Out> for Func
         where
@@ -879,13 +871,7 @@ macro_rules! impl_system_function {
 
 // Note that we rely on the highest impl to be <= the highest order of the tuple impls
 // of `SystemParam` created.
-all_tuples!(
-    #[doc(fake_variadic)]
-    impl_system_function,
-    0,
-    16,
-    F
-);
+all_tuples!(impl_system_function, 0, 16, F);
 
 #[cfg(test)]
 mod tests {

From d9a3b03fe505183a775ab72bcdbfc8bbc3afdceb Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Wed, 25 Sep 2024 15:21:54 +0200
Subject: [PATCH 13/20] fix feature decl

---
 crates/bevy_app/src/lib.rs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/crates/bevy_app/src/lib.rs b/crates/bevy_app/src/lib.rs
index bcbd0afd9bc58..aac1cfddff875 100644
--- a/crates/bevy_app/src/lib.rs
+++ b/crates/bevy_app/src/lib.rs
@@ -1,4 +1,3 @@
-#![cfg_attr(docsrs, feature(doc_auto_cfg))]
 // `rustdoc_internals` is needed for `#[doc(fake_variadics)]`
 #![allow(internal_features)]
 #![cfg_attr(any(docsrs, docsrs_dep), feature(doc_auto_cfg, rustdoc_internals))]

From d16b04c0bf84ff1c2639bdcf3848a0599e577056 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Wed, 25 Sep 2024 18:06:16 +0200
Subject: [PATCH 14/20] feedback

---
 crates/bevy_ecs/src/query/fetch.rs            | 19 ++++++++++++++++---
 crates/bevy_reflect/src/func/reflect_fn.rs    | 12 ++----------
 .../bevy_reflect/src/func/reflect_fn_mut.rs   | 12 ++----------
 crates/bevy_reflect/src/tuple.rs              |  1 +
 4 files changed, 21 insertions(+), 23 deletions(-)

diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
index c9ca4adf0194e..15382058b63ed 100644
--- a/crates/bevy_ecs/src/query/fetch.rs
+++ b/crates/bevy_ecs/src/query/fetch.rs
@@ -2024,10 +2024,11 @@ macro_rules! impl_tuple_query_data {
 }
 
 macro_rules! impl_anytuple_fetch {
-    ($(($name: ident, $state: ident)),*) => {
+    ($(#[$meta:meta])* $(($name: ident, $state: ident)),*) => {
 
         #[allow(non_snake_case)]
         #[allow(clippy::unused_unit)]
+        $(#[$meta])*
         /// SAFETY:
         /// `fetch` accesses are a subset of the subqueries' accesses
         /// This is sound because `update_component_access` and `update_archetype_component_access` adds accesses according to the implementations of all the subqueries.
@@ -2159,8 +2160,20 @@ macro_rules! impl_anytuple_fetch {
     };
 }
 
-all_tuples!(impl_tuple_query_data, 0, 15, F, S);
-all_tuples!(impl_anytuple_fetch, 0, 15, F, S);
+all_tuples!(
+    impl_tuple_query_data,
+    0,
+    15,
+    F,
+    S
+);
+all_tuples!(
+    impl_anytuple_fetch,
+    0,
+    15,
+    F,
+    S
+);
 
 /// [`WorldQuery`] used to nullify queries by turning `Query<D>` into `Query<NopWorldQuery<D>>`
 ///
diff --git a/crates/bevy_reflect/src/func/reflect_fn.rs b/crates/bevy_reflect/src/func/reflect_fn.rs
index f66a7ce709700..6e29fd4e075eb 100644
--- a/crates/bevy_reflect/src/func/reflect_fn.rs
+++ b/crates/bevy_reflect/src/func/reflect_fn.rs
@@ -76,9 +76,8 @@ pub trait ReflectFn<'env, Marker>: ReflectFnMut<'env, Marker> {
 /// - `Fn(&mut Receiver, arg0, arg1, ..., argN) -> &mut R`
 /// - `Fn(&mut Receiver, arg0, arg1, ..., argN) -> &R`
 macro_rules! impl_reflect_fn {
-    ($(#[$meta:meta])* $(($Arg:ident, $arg:ident)),*) => {
+    ($(($Arg:ident, $arg:ident)),*) => {
         // === (...) -> ReturnType === //
-        $(#[$meta])*
         impl<'env, $($Arg,)* ReturnType, Function> ReflectFn<'env, fn($($Arg),*) -> [ReturnType]> for Function
         where
             $($Arg: FromArg,)*
@@ -198,11 +197,4 @@ macro_rules! impl_reflect_fn {
     };
 }
 
-all_tuples!(
-    #[doc(fake_variadic)]
-    impl_reflect_fn,
-    0,
-    15,
-    Arg,
-    arg
-);
+all_tuples!(impl_reflect_fn, 0, 15, Arg, arg);
diff --git a/crates/bevy_reflect/src/func/reflect_fn_mut.rs b/crates/bevy_reflect/src/func/reflect_fn_mut.rs
index 008e52f334a64..be73aca79b6bb 100644
--- a/crates/bevy_reflect/src/func/reflect_fn_mut.rs
+++ b/crates/bevy_reflect/src/func/reflect_fn_mut.rs
@@ -82,9 +82,8 @@ pub trait ReflectFnMut<'env, Marker> {
 /// - `FnMut(&mut Receiver, arg0, arg1, ..., argN) -> &mut R`
 /// - `FnMut(&mut Receiver, arg0, arg1, ..., argN) -> &R`
 macro_rules! impl_reflect_fn_mut {
-    ($(#[$meta:meta])* $(($Arg:ident, $arg:ident)),*) => {
+    ($(($Arg:ident, $arg:ident)),*) => {
         // === (...) -> ReturnType === //
-        $(#[$meta])*
         impl<'env, $($Arg,)* ReturnType, Function> ReflectFnMut<'env, fn($($Arg),*) -> [ReturnType]> for Function
         where
             $($Arg: FromArg,)*
@@ -204,11 +203,4 @@ macro_rules! impl_reflect_fn_mut {
     };
 }
 
-all_tuples!(
-    #[doc(fake_variadic)]
-    impl_reflect_fn_mut,
-    0,
-    15,
-    Arg,
-    arg
-);
+all_tuples!(impl_reflect_fn_mut, 0, 15, Arg, arg);
diff --git a/crates/bevy_reflect/src/tuple.rs b/crates/bevy_reflect/src/tuple.rs
index 02be82faa18ab..caf59fd518870 100644
--- a/crates/bevy_reflect/src/tuple.rs
+++ b/crates/bevy_reflect/src/tuple.rs
@@ -671,6 +671,7 @@ impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J
 
 macro_rules! impl_type_path_tuple {
     ($(#[$meta:meta])*) => {
+        $(#[$meta])*
         impl TypePath for () {
             fn type_path() -> &'static str {
                 "()"

From 5d4351d76d542c0872753efc56db60ab22371a7a Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Wed, 25 Sep 2024 18:37:34 +0200
Subject: [PATCH 15/20] fmt

---
 crates/bevy_ecs/src/query/fetch.rs | 16 ++--------------
 1 file changed, 2 insertions(+), 14 deletions(-)

diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
index 15382058b63ed..da8ea9fe122b9 100644
--- a/crates/bevy_ecs/src/query/fetch.rs
+++ b/crates/bevy_ecs/src/query/fetch.rs
@@ -2160,20 +2160,8 @@ macro_rules! impl_anytuple_fetch {
     };
 }
 
-all_tuples!(
-    impl_tuple_query_data,
-    0,
-    15,
-    F,
-    S
-);
-all_tuples!(
-    impl_anytuple_fetch,
-    0,
-    15,
-    F,
-    S
-);
+all_tuples!(impl_tuple_query_data, 0, 15, F, S);
+all_tuples!(impl_anytuple_fetch, 0, 15, F, S);
 
 /// [`WorldQuery`] used to nullify queries by turning `Query<D>` into `Query<NopWorldQuery<D>>`
 ///

From 6292b91dc2b48c689b8ad41d35c372a1aaf95734 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Fri, 27 Sep 2024 14:35:23 +0200
Subject: [PATCH 16/20] feedback

---
 crates/bevy_ecs/src/query/fetch.rs | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
index da8ea9fe122b9..725252a9184bb 100644
--- a/crates/bevy_ecs/src/query/fetch.rs
+++ b/crates/bevy_ecs/src/query/fetch.rs
@@ -2008,10 +2008,10 @@ unsafe impl<T: Component> ReadOnlyQueryData for Has<T> {}
 pub struct AnyOf<T>(PhantomData<T>);
 
 macro_rules! impl_tuple_query_data {
-    ($(($name: ident, $state: ident)),*) => {
-
+    ($(#[$meta:meta])* $(($name: ident, $state: ident)),*) => {
         #[allow(non_snake_case)]
         #[allow(clippy::unused_unit)]
+        $(#[$meta])*
         // SAFETY: defers to soundness `$name: WorldQuery` impl
         unsafe impl<$($name: QueryData),*> QueryData for ($($name,)*) {
             type ReadOnly = ($($name::ReadOnly,)*);
@@ -2024,11 +2024,10 @@ macro_rules! impl_tuple_query_data {
 }
 
 macro_rules! impl_anytuple_fetch {
-    ($(#[$meta:meta])* $(($name: ident, $state: ident)),*) => {
+    ($(($name: ident, $state: ident)),*) => {
 
         #[allow(non_snake_case)]
         #[allow(clippy::unused_unit)]
-        $(#[$meta])*
         /// SAFETY:
         /// `fetch` accesses are a subset of the subqueries' accesses
         /// This is sound because `update_component_access` and `update_archetype_component_access` adds accesses according to the implementations of all the subqueries.

From 06a681a9ba2b952d182fec3c55ada991ee40e8d7 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Fri, 27 Sep 2024 14:36:45 +0200
Subject: [PATCH 17/20] feedback and fixes

---
 crates/bevy_ecs/src/bundle.rs      | 1 +
 crates/bevy_ecs/src/query/fetch.rs | 1 +
 2 files changed, 2 insertions(+)

diff --git a/crates/bevy_ecs/src/bundle.rs b/crates/bevy_ecs/src/bundle.rs
index bbe114a2fee87..5eeb01c8699cc 100644
--- a/crates/bevy_ecs/src/bundle.rs
+++ b/crates/bevy_ecs/src/bundle.rs
@@ -280,6 +280,7 @@ macro_rules! tuple_impl {
             }
         }
 
+        $(#[$meta])*
         impl<$($name: Bundle),*> DynamicBundle for ($($name,)*) {
             #[allow(unused_variables, unused_mut)]
             #[inline(always)]
diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
index 725252a9184bb..76c2274a6fbb1 100644
--- a/crates/bevy_ecs/src/query/fetch.rs
+++ b/crates/bevy_ecs/src/query/fetch.rs
@@ -2017,6 +2017,7 @@ macro_rules! impl_tuple_query_data {
             type ReadOnly = ($($name::ReadOnly,)*);
         }
 
+        $(#[$meta])*
         /// SAFETY: each item in the tuple is read only
         unsafe impl<$($name: ReadOnlyQueryData),*> ReadOnlyQueryData for ($($name,)*) {}
 

From 26bc84d2dcd7fe686fcb7e8f9558686b3ead340a Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Sun, 29 Sep 2024 03:56:55 +0200
Subject: [PATCH 18/20] undo accidental changes

---
 crates/bevy_ecs/src/query/fetch.rs    | 9 ++++++++-
 crates/bevy_ecs/src/system/builder.rs | 2 +-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
index 24fb22291fb58..17d92fc97930a 100644
--- a/crates/bevy_ecs/src/query/fetch.rs
+++ b/crates/bevy_ecs/src/query/fetch.rs
@@ -2165,7 +2165,14 @@ macro_rules! impl_anytuple_fetch {
     };
 }
 
-all_tuples!(impl_tuple_query_data, 0, 15, F, S);
+all_tuples!(
+    #[doc(fake_variadic)]
+    impl_tuple_query_data,
+    0,
+    15,
+    F,
+    S
+);
 all_tuples!(impl_anytuple_fetch, 0, 15, F, S);
 
 /// [`WorldQuery`] used to nullify queries by turning `Query<D>` into `Query<NopWorldQuery<D>>`
diff --git a/crates/bevy_ecs/src/system/builder.rs b/crates/bevy_ecs/src/system/builder.rs
index 21f1756ce8852..279cc41381af5 100644
--- a/crates/bevy_ecs/src/system/builder.rs
+++ b/crates/bevy_ecs/src/system/builder.rs
@@ -233,7 +233,7 @@ unsafe impl<P: SystemParam, B: SystemParamBuilder<P>> SystemParamBuilder<Vec<P>>
 pub struct ParamSetBuilder<T>(pub T);
 
 macro_rules! impl_param_set_builder_tuple {
-        ($(($param: ident, $builder: ident, $meta: ident)),*) => {
+    ($(($param: ident, $builder: ident, $meta: ident)),*) => {
         // SAFETY: implementors of each `SystemParamBuilder` in the tuple have validated their impls
         unsafe impl<'w, 's, $($param: SystemParam,)* $($builder: SystemParamBuilder<$param>,)*> SystemParamBuilder<ParamSet<'w, 's, ($($param,)*)>> for ParamSetBuilder<($($builder,)*)> {
             #[allow(non_snake_case)]

From 80e5379e911191cfc69fa07a88930c12863c3c19 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Sun, 29 Sep 2024 03:58:54 +0200
Subject: [PATCH 19/20] undo strange change

---
 crates/bevy_ecs/src/system/observer_system.rs | 37 -------------------
 1 file changed, 37 deletions(-)

diff --git a/crates/bevy_ecs/src/system/observer_system.rs b/crates/bevy_ecs/src/system/observer_system.rs
index 044c0e5901df9..55173ccf4f22a 100644
--- a/crates/bevy_ecs/src/system/observer_system.rs
+++ b/crates/bevy_ecs/src/system/observer_system.rs
@@ -51,43 +51,6 @@ where
     }
 }
 
-macro_rules! impl_system_function {
-    ($($param: ident),*) => {
-        #[allow(non_snake_case)]
-        impl<E: 'static, B: Bundle, Out, Func: Send + Sync + 'static, $($param: SystemParam),*> SystemParamFunction<fn(Trigger<E, B>, $($param,)*)> for Func
-        where
-        for <'a> &'a mut Func:
-                FnMut(Trigger<E, B>, $($param),*) -> Out +
-                FnMut(Trigger<E, B>, $(SystemParamItem<$param>),*) -> Out, Out: 'static
-        {
-            type In = Trigger<'static, E, B>;
-            type Out = Out;
-            type Param = ($($param,)*);
-            #[inline]
-            fn run(&mut self, input: Trigger<'static, E, B>, param_value: SystemParamItem< ($($param,)*)>) -> Out {
-                #[allow(clippy::too_many_arguments)]
-                fn call_inner<E: 'static, B: Bundle, Out, $($param,)*>(
-                    mut f: impl FnMut(Trigger<'static, E, B>, $($param,)*) -> Out,
-                    input: Trigger<'static, E, B>,
-                    $($param: $param,)*
-                ) -> Out{
-                    f(input, $($param,)*)
-                }
-                let ($($param,)*) = param_value;
-                call_inner(self, input, $($param),*)
-            }
-        }
-    }
-}
-
-all_tuples!(
-    #[doc(fake_variadic)]
-    impl_system_function,
-    0,
-    16,
-    F
-);
-
 #[cfg(test)]
 mod tests {
     use crate::{

From 0e3999dcfb69a6faa02322e70a29510425fbe971 Mon Sep 17 00:00:00 2001
From: Benjamin Brienen <Benjamin.Brienen@outlook.com>
Date: Sun, 29 Sep 2024 04:00:08 +0200
Subject: [PATCH 20/20] undo accidental change

---
 crates/bevy_reflect/src/tuple.rs | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/crates/bevy_reflect/src/tuple.rs b/crates/bevy_reflect/src/tuple.rs
index caf59fd518870..af0e8c9348170 100644
--- a/crates/bevy_reflect/src/tuple.rs
+++ b/crates/bevy_reflect/src/tuple.rs
@@ -656,18 +656,18 @@ macro_rules! impl_reflect_tuple {
 }
 
 impl_reflect_tuple! {}
-impl_reflect_tuple! { 0: A}
-impl_reflect_tuple! { 0: A, 1: B}
-impl_reflect_tuple! { 0: A, 1: B, 2: C}
-impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D}
-impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E}
-impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F}
-impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G}
-impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H}
-impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I}
-impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J}
-impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K}
-impl_reflect_tuple! { 0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K, 11: L}
+impl_reflect_tuple! {0: A}
+impl_reflect_tuple! {0: A, 1: B}
+impl_reflect_tuple! {0: A, 1: B, 2: C}
+impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D}
+impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E}
+impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F}
+impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G}
+impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H}
+impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I}
+impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J}
+impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K}
+impl_reflect_tuple! {0: A, 1: B, 2: C, 3: D, 4: E, 5: F, 6: G, 7: H, 8: I, 9: J, 10: K, 11: L}
 
 macro_rules! impl_type_path_tuple {
     ($(#[$meta:meta])*) => {