Make WorldQuery meta types unnameable (bevyengine#7964)

shfty-rust · Mar 19, 2023 · 3ac8069 · 3ac8069
1 parent bfe079c
commit 3ac8069
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Showing 2 changed files with 33 additions and 28 deletions.
diff --git a/crates/bevy_ecs/macros/src/fetch.rs b/crates/bevy_ecs/macros/src/fetch.rs
@@ -176,7 +176,7 @@ pub fn derive_world_query_impl(ast: DeriveInput) -> TokenStream {
             &field_types
         };
 
-        quote! {
+        let item_struct = quote! {
             #derive_macro_call
             #[doc = "Automatically generated [`WorldQuery`] item type for [`"]
             #[doc = stringify!(#struct_name)]
@@ -186,7 +186,9 @@ pub fn derive_world_query_impl(ast: DeriveInput) -> TokenStream {
                 #(#(#field_attrs)* #field_visibilities #field_idents: <#field_types as #path::query::WorldQuery>::Item<'__w>,)*
                 #(#(#ignored_field_attrs)* #ignored_field_visibilities #ignored_field_idents: #ignored_field_types,)*
             }
+        };
 
+        let query_impl = quote! {
             #[doc(hidden)]
             #[doc = "Automatically generated internal [`WorldQuery`] fetch type for [`"]
             #[doc = stringify!(#struct_name)]
@@ -324,13 +326,14 @@ pub fn derive_world_query_impl(ast: DeriveInput) -> TokenStream {
                     true #(&& <#field_types>::matches_component_set(&state.#field_idents, _set_contains_id))*
                 }
             }
-        }
+        };
+        (item_struct, query_impl)
     };
 
-    let mutable_impl = impl_fetch(false);
-    let readonly_impl = if fetch_struct_attributes.is_mutable {
-        let world_query_impl = impl_fetch(true);
-        quote! {
+    let (mutable_struct, mutable_impl) = impl_fetch(false);
+    let (read_only_struct, read_only_impl) = if fetch_struct_attributes.is_mutable {
+        let (readonly_state, read_only_impl) = impl_fetch(true);
+        let read_only_structs = quote! {
             #[doc = "Automatically generated [`WorldQuery`] type for a read-only variant of [`"]
             #[doc = stringify!(#struct_name)]
             #[doc = "`]."]
@@ -340,10 +343,11 @@ pub fn derive_world_query_impl(ast: DeriveInput) -> TokenStream {
                 #(#(#ignored_field_attrs)* #ignored_field_visibilities #ignored_field_idents: #ignored_field_types,)*
             }
 
-            #world_query_impl
-        }
+            #readonly_state
+        };
+        (read_only_structs, read_only_impl)
     } else {
-        quote! {}
+        (quote! {}, quote! {})
     };
 
     let read_only_asserts = if fetch_struct_attributes.is_mutable {
@@ -367,24 +371,30 @@ pub fn derive_world_query_impl(ast: DeriveInput) -> TokenStream {
     };
 
     TokenStream::from(quote! {
-        #mutable_impl
-
-        #readonly_impl
-
-        #[doc(hidden)]
-        #[doc = "Automatically generated internal [`WorldQuery`] state type for [`"]
-        #[doc = stringify!(#struct_name)]
-        #[doc = "`], used for caching."]
-        #[automatically_derived]
-        #visibility struct #state_struct_name #user_impl_generics #user_where_clauses {
-            #(#field_idents: <#field_types as #path::query::WorldQuery>::State,)*
-            #(#ignored_field_idents: #ignored_field_types,)*
-        }
+        #mutable_struct
+
+        #read_only_struct
 
         /// SAFETY: we assert fields are readonly below
         unsafe impl #user_impl_generics #path::query::ReadOnlyWorldQuery
             for #read_only_struct_name #user_ty_generics #user_where_clauses {}
 
+        const _: () = {
+            #[doc(hidden)]
+            #[doc = "Automatically generated internal [`WorldQuery`] state type for [`"]
+            #[doc = stringify!(#struct_name)]
+            #[doc = "`], used for caching."]
+            #[automatically_derived]
+            #visibility struct #state_struct_name #user_impl_generics #user_where_clauses {
+                #(#field_idents: <#field_types as #path::query::WorldQuery>::State,)*
+                #(#ignored_field_idents: #ignored_field_types,)*
+            }
+
+            #mutable_impl
+
+            #read_only_impl
+        };
+
         #[allow(dead_code)]
         const _: () = {
             fn assert_readonly<T>()
@@ -412,7 +422,6 @@ pub fn derive_world_query_impl(ast: DeriveInput) -> TokenStream {
                 #(q.#ignored_field_idents;)*
                 #(q2.#field_idents;)*
                 #(q2.#ignored_field_idents;)*
-
             }
         };
     })

diff --git a/crates/bevy_ecs/src/query/fetch.rs b/crates/bevy_ecs/src/query/fetch.rs
@@ -92,16 +92,13 @@ use std::{cell::UnsafeCell, marker::PhantomData};
 ///
 /// ## Macro expansion
 ///
-/// Expanding the macro will declare three or six additional structs, depending on whether or not the struct is marked as mutable.
+/// Expanding the macro will declare one or three additional structs, depending on whether or not the struct is marked as mutable.
 /// For a struct named `X`, the additional structs will be:
 ///
 /// |Struct name|`mutable` only|Description|
 /// |:---:|:---:|---|
-/// |`XState`|---|Used as the [`State`] type for `X` and `XReadOnly`|
 /// |`XItem`|---|The type of the query item for `X`|
-/// |`XFetch`|---|Used as the [`Fetch`] type for `X`|
 /// |`XReadOnlyItem`|✓|The type of the query item for `XReadOnly`|
-/// |`XReadOnlyFetch`|✓|Used as the [`Fetch`] type for `XReadOnly`|
 /// |`XReadOnly`|✓|[`ReadOnly`] variant of `X`|
 ///
 /// ## Adding mutable references
@@ -296,7 +293,6 @@ use std::{cell::UnsafeCell, marker::PhantomData};
 /// [`Added`]: crate::query::Added
 /// [`fetch`]: Self::fetch
 /// [`Changed`]: crate::query::Changed
-/// [`Fetch`]: crate::query::WorldQuery::Fetch
 /// [`matches_component_set`]: Self::matches_component_set
 /// [`Or`]: crate::query::Or
 /// [`Query`]: crate::system::Query