Merge pull request #891 from godot-rust/feature/unicode-class-names

Support Unicode class names (Godot 4.4+)

Author: Bromeon

godot-codegen/src/generator/classes.rs

@@ -218,7 +218,7 @@ fn make_class(class: &Class, ctx: &mut Context, view: &ApiView) -> GeneratedClas
                     // Optimization note: instead of lazy init, could use separate static which is manually initialized during registration.
                     static CLASS_NAME: std::sync::OnceLock<ClassName> = std::sync::OnceLock::new();
 
-                    let name: &'static ClassName = CLASS_NAME.get_or_init(|| ClassName::alloc_next(#class_name_cstr));
+                    let name: &'static ClassName = CLASS_NAME.get_or_init(|| ClassName::alloc_next_ascii(#class_name_cstr));
                     *name
                 }
 

godot-core/src/meta/class_name.rs

@@ -134,12 +134,41 @@ impl ClassName {
     }
 
     #[doc(hidden)]
-    pub fn alloc_next(class_name_cstr: &'static CStr) -> Self {
+    pub fn alloc_next_ascii(class_name_cstr: &'static CStr) -> Self {
+        let utf8 = class_name_cstr
+            .to_str()
+            .expect("class name is invalid UTF-8");
+
+        assert!(
+            utf8.is_ascii(),
+            "ClassName::alloc_next_ascii() with non-ASCII Unicode string '{}'",
+            utf8
+        );
+
         let global_index = insert_class(ClassNameSource::Borrowed(class_name_cstr));
 
         Self { global_index }
     }
 
+    #[doc(hidden)]
+    pub fn alloc_next_unicode(class_name_str: &'static str) -> Self {
+        assert!(
+            cfg!(since_api = "4.4"),
+            "Before Godot 4.4, class names must be ASCII, but '{class_name_str}' is not.\nSee https://github.com/godotengine/godot/pull/96501."
+        );
+
+        assert!(
+            !class_name_str.is_ascii(),
+            "ClassName::alloc_next_unicode() with ASCII string '{}'",
+            class_name_str
+        );
+
+        // StringNames use optimized 1-byte-per-char layout for Latin-1/ASCII, so Unicode can as well use the regular constructor.
+        let global_index = insert_class(ClassNameSource::Owned(class_name_str.to_owned()));
+
+        Self { global_index }
+    }
+
     #[doc(hidden)]
     pub fn is_none(&self) -> bool {
         self.global_index == 0

godot-core/src/registry/class.rs

@@ -399,7 +399,7 @@ fn register_class_raw(mut info: ClassRegistrationInfo) {
     // This can happen during hot reload if a class changes base type in an incompatible way (e.g. RefCounted -> Node).
     if registration_failed {
         godot_error!(
-            "Failed to register class `{class_name}`; check preceding Godot stderr messages"
+            "Failed to register class `{class_name}`; check preceding Godot stderr messages."
         );
     }
 

godot-macros/src/class/derive_godot_class.rs

@@ -34,7 +34,14 @@ pub fn derive_godot_class(item: venial::Item) -> ParseResult<TokenStream> {
         .map_or_else(|| class.name.clone(), |rename| rename)
         .to_string();
 
-    let class_name_cstr = util::c_str(&class_name_str);
+    // Determine if we can use ASCII for the class name (in most cases).
+    let class_name_allocation = if class_name_str.is_ascii() {
+        let c_str = util::c_str(&class_name_str);
+        quote! { ClassName::alloc_next_ascii(#c_str) }
+    } else {
+        quote! { ClassName::alloc_next_unicode(#class_name_str) }
+    };
+
     let class_name_obj = util::class_name_obj(class_name);
 
     let is_internal = struct_cfg.is_internal;
@@ -123,7 +130,7 @@ pub fn derive_godot_class(item: venial::Item) -> ParseResult<TokenStream> {
                 // Optimization note: instead of lazy init, could use separate static which is manually initialized during registration.
                 static CLASS_NAME: std::sync::OnceLock<ClassName> = std::sync::OnceLock::new();
 
-                let name: &'static ClassName = CLASS_NAME.get_or_init(|| ClassName::alloc_next(#class_name_cstr));
+                let name: &'static ClassName = CLASS_NAME.get_or_init(|| #class_name_allocation);
                 *name
             }
         }

itest/rust/src/register_tests/mod.rs

@@ -10,7 +10,7 @@ mod conversion_test;
 mod derive_godotconvert_test;
 mod func_test;
 mod gdscript_ffi_test;
-mod keyword_parameters_test;
+mod naming_tests;
 mod option_ffi_test;
 mod var_test;
 

itest/rust/src/register_tests/keyword_parameters_test.rs renamed to itest/rust/src/register_tests/naming_tests.rs

@@ -26,3 +26,8 @@ impl IEditorExportPlugin for KeywordParameterEditorExportPlugin {
     fn get_customization_configuration_hash(&self) -> u64 { unreachable!() }
     fn get_name(&self) -> GString { unreachable!() }
 }
+
+#[cfg(since_api = "4.4")]
+#[derive(GodotClass)]
+#[class(no_init)]
+struct 统一码 {}