RenderResource derive correctly propogating generics

bevyengine · Apr 30, 2021 · a306d1d · a306d1d
1 parent ad15982
commit a306d1d
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Showing 3 changed files with 54 additions and 3 deletions.
diff --git a/crates/bevy_derive/src/render_resource.rs b/crates/bevy_derive/src/render_resource.rs
@@ -11,9 +11,10 @@ pub fn derive_render_resource(input: TokenStream) -> TokenStream {
     let bevy_asset_path: Path = get_path(&modules.bevy_asset);
     let bevy_core_path: Path = get_path(&modules.bevy_core);
     let struct_name = &ast.ident;
+    let (impl_generics, type_generics, where_clause) = &ast.generics.split_for_impl();
 
     TokenStream::from(quote! {
-        impl #bevy_render_path::renderer::RenderResource for #struct_name {
+        impl #impl_generics #bevy_render_path::renderer::RenderResource for #struct_name #type_generics #where_clause {
             fn resource_type(&self) -> Option<#bevy_render_path::renderer::RenderResourceType> {
                 Some(#bevy_render_path::renderer::RenderResourceType::Buffer)
             }

diff --git a/crates/bevy_derive/src/render_resources.rs b/crates/bevy_derive/src/render_resources.rs
@@ -42,11 +42,12 @@ pub fn derive_render_resources(input: TokenStream) -> TokenStream {
             attributes
         });
     let struct_name = &ast.ident;
+    let (impl_generics, type_generics, where_clause) = &ast.generics.split_for_impl();
     let struct_name_string = struct_name.to_string();
 
     if attributes.from_self {
         TokenStream::from(quote! {
-            impl #bevy_render_path::renderer::RenderResources for #struct_name {
+            impl #impl_generics #bevy_render_path::renderer::RenderResources for #struct_name #type_generics #where_clause {
                 fn render_resources_len(&self) -> usize {
                     1
                 }
@@ -154,7 +155,7 @@ pub fn derive_render_resources(input: TokenStream) -> TokenStream {
                 #(#render_resource_hints,)*
             ];
 
-            impl #bevy_render_path::renderer::RenderResources for #struct_name {
+            impl #impl_generics #bevy_render_path::renderer::RenderResources for #struct_name #type_generics #where_clause {
                 fn render_resources_len(&self) -> usize {
                     #render_resource_count
                 }

diff --git a/crates/bevy_render/src/renderer/render_resource/render_resource.rs b/crates/bevy_render/src/renderer/render_resource/render_resource.rs
@@ -273,3 +273,52 @@ impl RenderResources for bevy_transform::prelude::GlobalTransform {
         RenderResourceIterator::new(self)
     }
 }
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[derive(RenderResource, Bytes)]
+    #[as_crate(bevy_render)]
+    struct GenericRenderResource<T>
+    where
+        T: Bytes + Send + Sync + 'static,
+    {
+        value: T,
+    }
+
+    #[derive(RenderResources)]
+    #[as_crate(bevy_render)]
+    struct GenericRenderResources<T>
+    where
+        T: RenderResource + Send + Sync + 'static,
+    {
+        resource: T,
+    }
+
+    #[derive(Bytes, RenderResource, RenderResources)]
+    #[render_resources(from_self)]
+    #[as_crate(bevy_render)]
+    struct FromSelfGenericRenderResources<T>
+    where
+        T: Bytes + Send + Sync + 'static,
+    {
+        value: T,
+    }
+
+    fn test_impl_render_resource(_: &impl RenderResource) {}
+    fn test_impl_render_resources(_: &impl RenderResources) {}
+
+    #[test]
+    fn test_generic_render_resource_derive() {
+        let resource = GenericRenderResource { value: 42 };
+        test_impl_render_resource(&resource);
+
+        let resources = GenericRenderResources { resource };
+        test_impl_render_resources(&resources);
+
+        let from_self_resources = FromSelfGenericRenderResources { value: 42 };
+        test_impl_render_resource(&from_self_resources);
+        test_impl_render_resources(&from_self_resources);
+    }
+}