From 85d264c3e21e9df9a82985d8fbf7961899547c93 Mon Sep 17 00:00:00 2001
From: Dmitry Stepanov <d1maxa@yandex.ru>
Date: Tue, 9 Jan 2024 12:31:22 +0300
Subject: [PATCH] proc-macro for TypeUuidProvider

- allows to add `#[type_uuid(id = "15a8ecd6-a09f-4c5d-b9f9-b7f0e8a44ac9")]` attribute to types that `#[derive(TypeUuidProvider)]`
---
 fyrox-core-derive/src/lib.rs       | 10 +++++
 fyrox-core-derive/src/uuid.rs      | 28 ++++++++++++
 fyrox-core-derive/tests/it/main.rs |  1 +
 fyrox-core-derive/tests/it/uuid.rs | 12 ++++++
 fyrox-core/src/lib.rs              | 66 ++--------------------------
 fyrox-core/src/type_traits.rs      | 69 ++++++++++++++++++++++++++++++
 6 files changed, 123 insertions(+), 63 deletions(-)
 create mode 100644 fyrox-core-derive/src/uuid.rs
 create mode 100644 fyrox-core-derive/tests/it/uuid.rs
 create mode 100644 fyrox-core/src/type_traits.rs

diff --git a/fyrox-core-derive/src/lib.rs b/fyrox-core-derive/src/lib.rs
index 069c8409b..39654930b 100644
--- a/fyrox-core-derive/src/lib.rs
+++ b/fyrox-core-derive/src/lib.rs
@@ -1,4 +1,5 @@
 mod reflect;
+mod uuid;
 mod visit;
 
 use darling::FromDeriveInput;
@@ -43,3 +44,12 @@ pub fn impl_reflect(input: TokenStream) -> TokenStream {
 
     TokenStream::from(reflect_impl)
 }
+
+/// Implements `TypeUuidProvider` trait
+///
+/// User has to import `TypeUuidProvider` trait to use this macro.
+#[proc_macro_derive(TypeUuidProvider, attributes(type_uuid))]
+pub fn type_uuid(input: TokenStream) -> TokenStream {
+    let ast = parse_macro_input!(input as DeriveInput);
+    TokenStream::from(uuid::impl_type_uuid_provider(ast))
+}
diff --git a/fyrox-core-derive/src/uuid.rs b/fyrox-core-derive/src/uuid.rs
new file mode 100644
index 000000000..e14a7f2ec
--- /dev/null
+++ b/fyrox-core-derive/src/uuid.rs
@@ -0,0 +1,28 @@
+use darling::*;
+use proc_macro2::TokenStream as TokenStream2;
+use quote::*;
+use syn::*;
+
+#[derive(FromDeriveInput)]
+#[darling(attributes(type_uuid), supports(struct_any, enum_any))]
+pub struct TypeArgs {
+    pub ident: Ident,
+    pub generics: Generics,
+    pub id: String,
+}
+
+pub fn impl_type_uuid_provider(ast: DeriveInput) -> TokenStream2 {
+    let ty_args = TypeArgs::from_derive_input(&ast).unwrap();
+    let ty_ident = &ty_args.ident;
+    let id = &ty_args.id;
+
+    let (impl_generics, ty_generics, where_clause) = ty_args.generics.split_for_impl();
+
+    quote! {
+        impl #impl_generics TypeUuidProvider for #ty_ident #ty_generics #where_clause {
+            fn type_uuid() -> Uuid {
+                uuid!(#id)
+            }
+        }
+    }
+}
diff --git a/fyrox-core-derive/tests/it/main.rs b/fyrox-core-derive/tests/it/main.rs
index 547afb7ef..21762ffc5 100644
--- a/fyrox-core-derive/tests/it/main.rs
+++ b/fyrox-core-derive/tests/it/main.rs
@@ -6,4 +6,5 @@
 // trace_macros!(true);
 
 pub mod reflect;
+pub mod uuid;
 pub mod visit;
diff --git a/fyrox-core-derive/tests/it/uuid.rs b/fyrox-core-derive/tests/it/uuid.rs
new file mode 100644
index 000000000..24fa6e7ad
--- /dev/null
+++ b/fyrox-core-derive/tests/it/uuid.rs
@@ -0,0 +1,12 @@
+use fyrox_core::type_traits::prelude::*;
+use std::marker::PhantomData;
+
+#[derive(TypeUuidProvider)]
+#[type_uuid(id = "5fb10a22-4ea9-4a13-a58c-82f2734aefd8")]
+struct Foo {}
+
+#[derive(TypeUuidProvider)]
+#[type_uuid(id = "5fb10a22-4ea9-4a13-a58c-82f2734aefd9")]
+struct Bar<T> {
+    phantom: PhantomData<T>,
+}
diff --git a/fyrox-core/src/lib.rs b/fyrox-core/src/lib.rs
index 6642bbc4b..0c6d2b1d6 100644
--- a/fyrox-core/src/lib.rs
+++ b/fyrox-core/src/lib.rs
@@ -45,6 +45,7 @@ pub mod reflect;
 pub mod sparse;
 pub mod sstorage;
 pub mod task;
+pub mod type_traits;
 pub mod variable;
 pub mod visitor;
 pub mod watcher;
@@ -58,7 +59,6 @@ pub use notify;
 pub use js_sys;
 use std::iter::FromIterator;
 use std::marker::PhantomData;
-use uuid::Uuid;
 #[cfg(target_arch = "wasm32")]
 pub use wasm_bindgen;
 #[cfg(target_arch = "wasm32")]
@@ -66,6 +66,8 @@ pub use wasm_bindgen_futures;
 #[cfg(target_arch = "wasm32")]
 pub use web_sys;
 
+pub use type_traits::prelude::*;
+
 /// Defines as_(variant), as_mut_(variant) and is_(variant) methods.
 #[macro_export]
 macro_rules! define_is_as {
@@ -298,68 +300,6 @@ pub fn make_relative_path<P: AsRef<Path>>(path: P) -> Result<PathBuf, std::io::E
     }
 }
 
-/// A trait for an entity that has unique type identifier.
-pub trait TypeUuidProvider: Sized {
-    /// Return type UUID.
-    fn type_uuid() -> Uuid;
-}
-
-#[macro_export]
-macro_rules! uuid_provider {
-    ($type:ident $(<$($generics:tt),*>)? = $uuid:expr) => {
-        impl$(<$($generics),*>)? $crate::TypeUuidProvider for $type $(<$($generics),*>)? {
-            fn type_uuid() -> $crate::uuid::Uuid {
-                $crate::uuid::uuid!($uuid)
-            }
-        }
-    };
-}
-
-#[macro_export]
-macro_rules! stub_uuid_provider {
-    ($type:ty) => {
-        impl $crate::TypeUuidProvider for $type {
-            fn type_uuid() -> $crate::uuid::Uuid {
-                unimplemented!()
-            }
-        }
-    };
-}
-
-uuid_provider!(u8 = "7a8c337c-0219-466b-92b5-81460fa9c836");
-uuid_provider!(i8 = "3036f00e-5986-4ac3-8763-19e51d0889d7");
-uuid_provider!(u16 = "c662169d-cc3b-453c-bdf3-e0104ac3b966");
-uuid_provider!(i16 = "abce35a9-5e7b-4f7e-a729-2620a9806a6b");
-uuid_provider!(u32 = "8c4d2541-76a5-4dd8-9eb1-10222d2d6912");
-uuid_provider!(i32 = "7413ddd4-71ce-484d-a808-4f3479f5712d");
-uuid_provider!(u64 = "d1a45bd5-5066-4b28-b103-95c59c230e77");
-uuid_provider!(i64 = "35b89368-805f-486d-b3b1-fd3e86b5d645");
-uuid_provider!(f32 = "479e29c6-85fd-4bb8-b311-7b98793b8bf6");
-uuid_provider!(f64 = "dac09d54-d069-47f4-aa0e-aa0057cc2b52");
-uuid_provider!(usize = "620e24e3-fb51-48c6-a885-91d65135c5c9");
-uuid_provider!(isize = "0a06591a-1c66-4299-ba6f-2b205b795575");
-uuid_provider!(bool = "3b104074-9d39-4a2b-b974-da8cc1759fe8");
-
-impl<T: TypeUuidProvider> TypeUuidProvider for Option<T> {
-    fn type_uuid() -> Uuid {
-        combine_uuids(
-            uuid::uuid!("ffe06d3b-0d07-42cd-886b-5248f6ca7f7d"),
-            T::type_uuid(),
-        )
-    }
-}
-
-#[inline]
-pub fn combine_uuids(a: Uuid, b: Uuid) -> Uuid {
-    let mut combined_bytes = a.into_bytes();
-
-    for (src, dest) in b.into_bytes().into_iter().zip(combined_bytes.iter_mut()) {
-        *dest ^= src;
-    }
-
-    Uuid::from_bytes(combined_bytes)
-}
-
 /// "Transmutes" array of any sized type to a slice of bytes.
 pub fn array_as_u8_slice<T: Sized>(v: &[T]) -> &'_ [u8] {
     // SAFETY: It is safe to reinterpret data to read it.
diff --git a/fyrox-core/src/type_traits.rs b/fyrox-core/src/type_traits.rs
new file mode 100644
index 000000000..60fa978be
--- /dev/null
+++ b/fyrox-core/src/type_traits.rs
@@ -0,0 +1,69 @@
+pub use fyrox_core_derive::TypeUuidProvider;
+use uuid::Uuid;
+
+pub mod prelude {
+    pub use super::{combine_uuids, TypeUuidProvider};
+    pub use uuid::{uuid, Uuid};
+}
+
+/// A trait for an entity that has unique type identifier.
+pub trait TypeUuidProvider: Sized {
+    /// Return type UUID.
+    fn type_uuid() -> Uuid;
+}
+
+#[macro_export]
+macro_rules! uuid_provider {
+    ($type:ident $(<$($generics:tt),*>)? = $uuid:expr) => {
+        impl$(<$($generics),*>)? $crate::type_traits::TypeUuidProvider for $type $(<$($generics),*>)? {
+            fn type_uuid() -> $crate::uuid::Uuid {
+                $crate::uuid::uuid!($uuid)
+            }
+        }
+    };
+}
+
+#[macro_export]
+macro_rules! stub_uuid_provider {
+    ($type:ty) => {
+        impl $crate::TypeUuidProvider for $type {
+            fn type_uuid() -> $crate::uuid::Uuid {
+                unimplemented!()
+            }
+        }
+    };
+}
+
+uuid_provider!(u8 = "7a8c337c-0219-466b-92b5-81460fa9c836");
+uuid_provider!(i8 = "3036f00e-5986-4ac3-8763-19e51d0889d7");
+uuid_provider!(u16 = "c662169d-cc3b-453c-bdf3-e0104ac3b966");
+uuid_provider!(i16 = "abce35a9-5e7b-4f7e-a729-2620a9806a6b");
+uuid_provider!(u32 = "8c4d2541-76a5-4dd8-9eb1-10222d2d6912");
+uuid_provider!(i32 = "7413ddd4-71ce-484d-a808-4f3479f5712d");
+uuid_provider!(u64 = "d1a45bd5-5066-4b28-b103-95c59c230e77");
+uuid_provider!(i64 = "35b89368-805f-486d-b3b1-fd3e86b5d645");
+uuid_provider!(f32 = "479e29c6-85fd-4bb8-b311-7b98793b8bf6");
+uuid_provider!(f64 = "dac09d54-d069-47f4-aa0e-aa0057cc2b52");
+uuid_provider!(usize = "620e24e3-fb51-48c6-a885-91d65135c5c9");
+uuid_provider!(isize = "0a06591a-1c66-4299-ba6f-2b205b795575");
+uuid_provider!(bool = "3b104074-9d39-4a2b-b974-da8cc1759fe8");
+
+impl<T: TypeUuidProvider> TypeUuidProvider for Option<T> {
+    fn type_uuid() -> Uuid {
+        combine_uuids(
+            uuid::uuid!("ffe06d3b-0d07-42cd-886b-5248f6ca7f7d"),
+            T::type_uuid(),
+        )
+    }
+}
+
+#[inline]
+pub fn combine_uuids(a: Uuid, b: Uuid) -> Uuid {
+    let mut combined_bytes = a.into_bytes();
+
+    for (src, dest) in b.into_bytes().into_iter().zip(combined_bytes.iter_mut()) {
+        *dest ^= src;
+    }
+
+    Uuid::from_bytes(combined_bytes)
+}