From 6b5289bd5eafc2981e829ef8921766a05c6715e4 Mon Sep 17 00:00:00 2001
From: theotherphil <phil.j.ellison@gmail.com>
Date: Sun, 8 Jun 2025 17:28:31 +0100
Subject: [PATCH] deny(missing_docs) for bevy_ecs_macros (#19523)

# Objective

Deny missing docs for bevy_ecs_macros, towards
https://github.com/bevyengine/bevy/issues/3492.

## Solution

More docs of the form

```
/// Does the thing
fn do_the_thing() {}
```

But I don't think the derive macros are where anyone is going to be
looking for details of these concepts and deny(missing_docs) inevitably
results in some items having noddy docs.
---
 crates/bevy_ecs/macros/src/lib.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/crates/bevy_ecs/macros/src/lib.rs b/crates/bevy_ecs/macros/src/lib.rs
index 114aff642b..133e5e9eaa 100644
--- a/crates/bevy_ecs/macros/src/lib.rs
+++ b/crates/bevy_ecs/macros/src/lib.rs
@@ -1,4 +1,5 @@
-#![expect(missing_docs, reason = "Not all docs are written yet, see #3492.")]
+//! Macros for deriving ECS traits.
+
 #![cfg_attr(docsrs, feature(doc_auto_cfg))]
 
 extern crate proc_macro;
@@ -29,6 +30,7 @@ enum BundleFieldKind {
 const BUNDLE_ATTRIBUTE_NAME: &str = "bundle";
 const BUNDLE_ATTRIBUTE_IGNORE_NAME: &str = "ignore";
 
+/// Implement the `Bundle` trait.
 #[proc_macro_derive(Bundle, attributes(bundle))]
 pub fn derive_bundle(input: TokenStream) -> TokenStream {
     let ast = parse_macro_input!(input as DeriveInput);
@@ -187,6 +189,7 @@ pub fn derive_bundle(input: TokenStream) -> TokenStream {
     })
 }
 
+/// Implement the `MapEntities` trait.
 #[proc_macro_derive(MapEntities, attributes(entities))]
 pub fn derive_map_entities(input: TokenStream) -> TokenStream {
     let ast = parse_macro_input!(input as DeriveInput);
@@ -522,16 +525,19 @@ pub(crate) fn bevy_ecs_path() -> syn::Path {
     BevyManifest::shared().get_path("bevy_ecs")
 }
 
+/// Implement the `Event` trait.
 #[proc_macro_derive(Event, attributes(event))]
 pub fn derive_event(input: TokenStream) -> TokenStream {
     component::derive_event(input)
 }
 
+/// Implement the `Resource` trait.
 #[proc_macro_derive(Resource)]
 pub fn derive_resource(input: TokenStream) -> TokenStream {
     component::derive_resource(input)
 }
 
+/// Implement the `Component` trait.
 #[proc_macro_derive(
     Component,
     attributes(component, require, relationship, relationship_target, entities)
@@ -540,6 +546,7 @@ pub fn derive_component(input: TokenStream) -> TokenStream {
     component::derive_component(input)
 }
 
+/// Implement the `FromWorld` trait.
 #[proc_macro_derive(FromWorld, attributes(from_world))]
 pub fn derive_from_world(input: TokenStream) -> TokenStream {
     let bevy_ecs_path = bevy_ecs_path();