feat: Add TypedThrough and IntoScript derive macros (#294)

Author: Joakker

crates/bevy_mod_scripting_derive/src/derive/into_script.rs

@@ -0,0 +1,25 @@
+use proc_macro2::TokenStream;
+use quote::quote;
+use syn::DeriveInput;
+
+pub fn into_script(input: TokenStream) -> TokenStream {
+    let (ident, generics) = match syn::parse2(input) {
+        Ok(DeriveInput {
+            ident, generics, ..
+        }) => (ident, generics),
+        Err(err) => return err.to_compile_error(),
+    };
+
+    let (impl_generics, type_generics, where_clause) = generics.split_for_impl();
+
+    quote! {
+        impl #impl_generics ::bevy_mod_scripting::bindings::function::into::IntoScript for #ident #type_generics #where_clause {
+            fn into_script(self, world: ::bevy_mod_scripting::core::bindings::WorldGuard) -> Result<::bevy_mod_scripting::core::bindings::script_value::ScriptValue, ::bevy_mod_scripting::core::error::InteropError> {
+                ::bevy_mod_scripting::core::bindings::function::into::IntoScript::into_script(
+                    ::bevy_mod_scripting::core::bindings::function::from::Val(self),
+                    world,
+                )
+            }
+        }
+    }
+}

crates/bevy_mod_scripting_derive/src/derive/mod.rs

@@ -0,0 +1,4 @@
+mod into_script;
+mod typed_through;
+
+pub use self::{into_script::into_script, typed_through::typed_through};

crates/bevy_mod_scripting_derive/src/derive/typed_through.rs

@@ -0,0 +1,23 @@
+use proc_macro2::TokenStream;
+use quote::quote;
+use syn::DeriveInput;
+
+pub fn typed_through(input: TokenStream) -> TokenStream {
+    let (ident, generics) = match syn::parse2(input) {
+        Ok(DeriveInput {
+            ident, generics, ..
+        }) => (ident, generics),
+        Err(err) => return err.to_compile_error(),
+    };
+
+    let (impl_generics, type_generics, where_clause) = generics.split_for_impl();
+
+    let turbofish = type_generics.as_turbofish();
+    quote! {
+        impl #impl_generics ::bevy_mod_scripting::core::docgen::typed_through::TypedThrough for #ident #type_generics #where_clause {
+            fn through_type_info() -> ::bevy_mod_scripting::core::docgen::typed_through::ThroughTypeInfo {
+                ::bevy_mod_scripting::core::docgen::typed_through::ThroughTypeInfo::TypeInfo(#ident #turbofish ::type_info())
+            }
+        }
+    }
+}

crates/bevy_mod_scripting_derive/src/lib.rs

@@ -4,6 +4,20 @@ use proc_macro2::{Span, TokenStream};
 use quote::{format_ident, quote_spanned, ToTokens};
 use syn::{spanned::Spanned, ImplItemFn, ItemImpl};
 
+mod derive;
+
+#[proc_macro_derive(TypedThrough)]
+/// Default implementation for the `TypedThrough` trait
+pub fn typed_through(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    derive::typed_through(input.into()).into()
+}
+
+#[proc_macro_derive(IntoScript)]
+/// Default implementation for the `IntoScript` trait
+pub fn into_script(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    derive::into_script(input.into()).into()
+}
+
 /// Derive macro for generating script bindings from an impl block.
 ///
 /// Does not support generics.