Merge pull request #27 from godot-rust/feature/api-string-names

GDExtension catch-up: class registration via `StringName`

.github/workflows/minimal-ci.yml

@@ -18,6 +18,8 @@ name: Minimal CI
 
 on:
   push:
+    branches:
+      - master
   pull_request:
 #    branches:
 #      - master

godot-codegen/src/central_generator.rs

@@ -124,7 +124,7 @@ fn make_sys_code(central_items: &CentralItems) -> String {
 
         impl VariantType {
             #[doc(hidden)]
-            pub fn from_ord(enumerator: crate::GDNativeVariantType) -> Self {
+            pub fn from_sys(enumerator: crate::GDNativeVariantType) -> Self {
                 // Annoying, but only stable alternative is transmute(), which dictates enum size
                 match enumerator {
                     0 => Self::Nil,
@@ -136,7 +136,7 @@ fn make_sys_code(central_items: &CentralItems) -> String {
             }
 
             #[doc(hidden)]
-            pub fn to_ord(self) -> crate::GDNativeVariantType {
+            pub fn sys(self) -> crate::GDNativeVariantType {
                 self as _
             }
         }
@@ -155,7 +155,7 @@ fn make_sys_code(central_items: &CentralItems) -> String {
 
         impl VariantOperator {
             #[doc(hidden)]
-            pub fn from_ord(enumerator: crate::GDNativeVariantOperator) -> Self {
+            pub fn from_sys(enumerator: crate::GDNativeVariantOperator) -> Self {
                 match enumerator {
                     #(
                         #variant_op_enumerators_ord => Self::#variant_op_enumerators_pascal,
@@ -165,7 +165,7 @@ fn make_sys_code(central_items: &CentralItems) -> String {
             }
 
             #[doc(hidden)]
-            pub fn to_ord(self) -> crate::GDNativeVariantOperator {
+            pub fn sys(self) -> crate::GDNativeVariantOperator {
                 self as _
             }
         }

godot-codegen/src/class_generator.rs

@@ -6,12 +6,12 @@
 
 //! Generates a file for each Godot class
 
-use proc_macro2::TokenStream;
+use proc_macro2::{Literal, TokenStream};
 use quote::{format_ident, quote};
 use std::path::{Path, PathBuf};
 
 use crate::api_parser::*;
-use crate::util::{c_str, ident, safe_ident, strlit, to_module_name, to_rust_type};
+use crate::util::{ident, safe_ident, strlit, to_module_name, to_rust_type};
 use crate::{special_cases, util, Context, GeneratedClass, GeneratedModule, RustTy};
 
 pub(crate) fn generate_class_files(
@@ -59,7 +59,7 @@ pub(crate) fn generate_class_files(
     out_files.push(out_path);
 }
 
-fn make_constructor(class: &Class, ctx: &Context, class_name_cstr: TokenStream) -> TokenStream {
+fn make_constructor(class: &Class, ctx: &Context, class_name_str: &Literal) -> TokenStream {
     if ctx.is_singleton(&class.name) {
         // Note: we cannot return &'static mut Self, as this would be very easy to mutably alias.
         // &'static Self would be possible, but we would lose the whole mutability information (even if that
@@ -69,7 +69,8 @@ fn make_constructor(class: &Class, ctx: &Context, class_name_cstr: TokenStream)
         quote! {
             pub fn singleton() -> Gd<Self> {
                 unsafe {
-                    let object_ptr = sys::interface_fn!(global_get_singleton)(#class_name_cstr);
+                    let class_name = StringName::from(#class_name_str);
+                    let object_ptr = sys::interface_fn!(global_get_singleton)(class_name.string_sys());
                     Gd::from_obj_sys(object_ptr)
                 }
             }
@@ -82,7 +83,8 @@ fn make_constructor(class: &Class, ctx: &Context, class_name_cstr: TokenStream)
         quote! {
             pub fn new() -> Gd<Self> {
                 unsafe {
-                    let object_ptr = sys::interface_fn!(classdb_construct_object)(#class_name_cstr);
+                    let class_name = StringName::from(#class_name_str);
+                    let object_ptr = sys::interface_fn!(classdb_construct_object)(class_name.string_sys());
                     //let instance = Self { object_ptr };
                     Gd::from_obj_sys(object_ptr)
                 }
@@ -94,7 +96,8 @@ fn make_constructor(class: &Class, ctx: &Context, class_name_cstr: TokenStream)
             #[must_use]
             pub fn new_alloc() -> Gd<Self> {
                 unsafe {
-                    let object_ptr = sys::interface_fn!(classdb_construct_object)(#class_name_cstr);
+                    let class_name = StringName::from(#class_name_str);
+                    let object_ptr = sys::interface_fn!(classdb_construct_object)(class_name.string_sys());
                     Gd::from_obj_sys(object_ptr)
                 }
             }
@@ -114,9 +117,8 @@ fn make_class(class: &Class, ctx: &mut Context) -> GeneratedClass {
 
     let name = ident(&class.name);
     let name_str = strlit(&class.name);
-    let name_cstr = c_str(&class.name);
 
-    let constructor = make_constructor(class, ctx, name_cstr);
+    let constructor = make_constructor(class, ctx, &name_str);
 
     let methods = make_methods(&class.methods, &class.name, ctx);
     let enums = make_enums(&class.enums, &class.name, ctx);
@@ -356,7 +358,7 @@ fn make_method_definition(method: &Method, class_name: &str, ctx: &mut Context)
     let is_varcall = method.is_vararg;
     let (params, arg_exprs) = make_params(&method.arguments, is_varcall, ctx);
 
-    let method_name = special_cases::maybe_renamed(class_name, &method.name);
+    let method_name_str = special_cases::maybe_renamed(class_name, &method.name);
     /*if method.map_args(|args| args.is_empty()) {
         // Getters (i.e. 0 arguments) will be stripped of their `get_` prefix, to conform to Rust convention
         if let Some(remainder) = method_name.strip_prefix("get_") {
@@ -367,10 +369,7 @@ fn make_method_definition(method: &Method, class_name: &str, ctx: &mut Context)
             }
         }
     }*/
-    let method_name = safe_ident(method_name);
-
-    let c_method_name = c_str(&method.name);
-    let c_class_name = c_str(class_name);
+    let method_name = safe_ident(method_name_str);
     let hash = method.hash;
 
     // TODO &mut safety
@@ -393,7 +392,13 @@ fn make_method_definition(method: &Method, class_name: &str, ctx: &mut Context)
         quote! {
             #vis fn #method_name( #receiver #(, #params )*, varargs: &[Variant]) #return_decl {
                 unsafe {
-                    let method_bind = sys::interface_fn!(classdb_get_method_bind)(#c_class_name, #c_method_name, #hash);
+                    let class_name = StringName::from(#class_name);
+                    let method_name = StringName::from(#method_name_str);
+                    let method_bind = sys::interface_fn!(classdb_get_method_bind)(
+                        class_name.string_sys(),
+                        method_name.string_sys(),
+                        #hash
+                    );
                     let call_fn = sys::interface_fn!(object_method_bind_call);
 
                     let explicit_args = [
@@ -414,7 +419,13 @@ fn make_method_definition(method: &Method, class_name: &str, ctx: &mut Context)
         quote! {
             #vis fn #method_name( #receiver, #( #params ),* ) #return_decl {
                 unsafe {
-                    let method_bind = sys::interface_fn!(classdb_get_method_bind)(#c_class_name, #c_method_name, #hash);
+                    let class_name = StringName::from(#class_name);
+                    let method_name = StringName::from(#method_name_str);
+                    let method_bind = sys::interface_fn!(classdb_get_method_bind)(
+                        class_name.string_sys(),
+                        method_name.string_sys(),
+                        #hash
+                    );
                     let call_fn = sys::interface_fn!(object_method_bind_ptrcall);
 
                     let args = [
@@ -441,16 +452,17 @@ pub(crate) fn make_function_definition(
     let is_vararg = function.is_vararg;
     let (params, arg_exprs) = make_params(&function.arguments, is_vararg, ctx);
 
-    let function_name = safe_ident(&function.name);
-    let c_function_name = c_str(&function.name);
+    let function_name_str = &function.name;
+    let function_name = safe_ident(function_name_str);
     let hash = function.hash;
 
     let (return_decl, call) = make_utility_return(&function.return_type, ctx);
 
     quote! {
         pub fn #function_name( #( #params ),* ) #return_decl {
             let result = unsafe {
-                let call_fn = sys::interface_fn!(variant_get_ptr_utility_function)(#c_function_name, #hash);
+                let function_name = StringName::from(#function_name_str);
+                let call_fn = sys::interface_fn!(variant_get_ptr_utility_function)(function_name.string_sys(), #hash);
                 let call_fn = call_fn.unwrap_unchecked();
 
                 let args = [

godot-codegen/src/util.rs

@@ -218,14 +218,6 @@ pub fn safe_ident(s: &str) -> Ident {
     }
 }
 
-// Code duplicated between here and godot-macros
-pub fn c_str(s: &str) -> TokenStream {
-    let s = Literal::string(&format!("{}\0", s));
-    quote! {
-        #s.as_ptr() as *const i8
-    }
-}
-
 pub fn strlit(s: &str) -> Literal {
     Literal::string(s)
 }

godot-core/src/builtin/macros.rs

@@ -6,12 +6,16 @@
 
 #![macro_use]
 
-macro_rules! impl_basic_trait_as_sys {
-    ( Drop for $Type:ty => $gd_method:ident ) => {
-        impl Drop for $Type {
+macro_rules! impl_builtin_traits_inner {
+    ( Default for $Type:ty => $gd_method:ident ) => {
+        impl Default for $Type {
             #[inline]
-            fn drop(&mut self) {
-                unsafe { (get_api().$gd_method)(self.sys_mut()) }
+            fn default() -> Self {
+                unsafe {
+                    let mut gd_val = sys::$GdType::default();
+                    (sys::method_table().$gd_method)(&mut gd_val);
+                    <$Type>::from_sys(gd_val)
+                }
             }
         }
     };
@@ -21,22 +25,23 @@ macro_rules! impl_basic_trait_as_sys {
             #[inline]
             fn clone(&self) -> Self {
                 unsafe {
-                    let mut result = sys::$GdType::default();
-                    (get_api().$gd_method)(&mut result, self.sys());
-                    <$Type>::from_sys(result)
+                    Self::from_sys_init(|self_ptr| {
+                        let ctor = sys::method_table().$gd_method;
+                        let args = [self.sys()];
+                        ctor(self_ptr, args.as_ptr());
+                    })
                 }
             }
         }
     };
 
-    ( Default for $Type:ty => $gd_method:ident ) => {
-        impl Default for $Type {
+    ( Drop for $Type:ty => $gd_method:ident ) => {
+        impl Drop for $Type {
             #[inline]
-            fn default() -> Self {
+            fn drop(&mut self) {
                 unsafe {
-                    let mut gd_val = sys::$GdType::default();
-                    (get_api().$gd_method)(&mut gd_val);
-                    <$Type>::from_sys(gd_val)
+                    let destructor = sys::method_table().$gd_method;
+            	    destructor(self.sys_mut());
                 }
             }
         }
@@ -58,7 +63,7 @@ macro_rules! impl_basic_trait_as_sys {
     };
 
     ( Eq for $Type:ty => $gd_method:ident ) => {
-		impl_basic_trait_as_sys!(PartialEq for $Type => $gd_method);
+		impl_builtin_traits_inner!(PartialEq for $Type => $gd_method);
         impl Eq for $Type {}
     };
 
@@ -86,7 +91,7 @@ macro_rules! impl_basic_trait_as_sys {
     };
 
     ( Ord for $Type:ty => $gd_method:ident ) => {
-        impl_basic_trait_as_sys!(PartialOrd for $Type => $gd_method);
+        impl_builtin_traits_inner!(PartialOrd for $Type => $gd_method);
         impl Ord for $Type {
             #[inline]
             fn cmp(&self, other: &Self) -> std::cmp::Ordering {
@@ -96,16 +101,16 @@ macro_rules! impl_basic_trait_as_sys {
     };
 }
 
-macro_rules! impl_traits_as_sys {
+macro_rules! impl_builtin_traits {
     (
         for $Type:ty {
             $( $Trait:ident => $gd_method:ident; )*
         }
     ) => (
         $(
-            impl_basic_trait_as_sys!(
+            impl_builtin_traits_inner! {
                 $Trait for $Type => $gd_method
-            );
+            }
         )*
     )
 }

godot-core/src/builtin/meta/class_name.rs

@@ -0,0 +1,43 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+use godot_ffi as sys;
+
+use std::fmt::{Display, Formatter, Result as FmtResult};
+
+use crate::builtin::*;
+use crate::obj::GodotClass;
+
+/// Utility to construct class names known at compile time.
+/// Cannot be a function since the backing string must be retained.
+#[derive(Eq, PartialEq, Hash, Clone, Debug)]
+pub struct ClassName {
+    backing: StringName,
+}
+
+impl ClassName {
+    pub fn new<T: GodotClass>() -> Self {
+        Self {
+            backing: StringName::from(T::CLASS_NAME),
+        }
+    }
+
+    pub fn from_static(string: &'static str) -> Self {
+        Self {
+            backing: StringName::from(string),
+        }
+    }
+
+    pub fn string_sys(&self) -> sys::GDNativeStringNamePtr {
+        self.backing.string_sys()
+    }
+}
+
+impl Display for ClassName {
+    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
+        self.backing.fmt(f)
+    }
+}