Merge pull request #747 from Dheatly23/fix-incorrect-itrait-impl

Constraint `ITrait` Bound to it's Corresponding Class

Author: Bromeon

godot-codegen/src/generator/virtual_traits.rs

@@ -23,6 +23,7 @@ pub fn make_virtual_methods_trait(
     view: &ApiView,
 ) -> TokenStream {
     let trait_name = ident(trait_name_str);
+    let class_name = &class.name().rust_ty;
 
     let virtual_method_fns = make_all_virtual_methods(class, all_base_names, view);
     let special_virtual_methods = make_special_virtual_methods(notification_enum_name);
@@ -34,7 +35,7 @@ pub fn make_virtual_methods_trait(
         #[allow(unused_variables)]
         #[allow(clippy::unimplemented)]
         #cfg_attributes
-        pub trait #trait_name: crate::obj::GodotClass + crate::private::You_forgot_the_attribute__godot_api {
+        pub trait #trait_name: crate::obj::GodotClass<Base = #class_name> + crate::private::You_forgot_the_attribute__godot_api {
             #special_virtual_methods
             #( #virtual_method_fns )*
         }

godot-macros/src/lib.rs

@@ -547,6 +547,21 @@ pub fn derive_godot_class(input: TokenStream) -> TokenStream {
 /// }
 /// ```
 ///
+/// Using _any_ trait other than the one corresponding with the base class will result in compilation failure.
+///
+/// ```compile_fail
+/// # use godot::prelude::*;
+/// #[derive(GodotClass)]
+/// #[class(init, base=Node3D)]
+/// pub struct My3DNode;
+///
+/// #[godot_api]
+/// impl INode for My3DNode {
+///     fn ready(&mut self) {
+///         godot_print!("Hello World!");
+///     }
+/// }
+/// ```
 ///
 /// # User-defined functions
 ///