Implement #[property(rpc = "mode")]

Author: chitoyuu

gdnative-derive/src/lib.rs

@@ -13,6 +13,7 @@ use syn::{parse::Parser, AttributeArgs, DeriveInput, ItemFn, ItemImpl, ItemType}
 mod methods;
 mod native_script;
 mod profiled;
+mod syntax;
 mod utils;
 mod varargs;
 mod variant;
@@ -268,6 +269,11 @@ pub fn profiled(meta: TokenStream, input: TokenStream) -> TokenStream {
 ///
 ///   Hides the property from the editor. Does not prevent it from being sent over network or saved in storage.
 ///
+/// - `rpc = "selected_rpc"`
+///
+///   Sets the [Multiplayer API RPC Mode](https://docs.godotengine.org/en/stable/classes/class_multiplayerapi.html?highlight=RPC#enumerations) for the property.
+///   See the `#[method]` documentation below for possible values and their semantics.
+///
 /// ### `#[methods]`
 /// Adds the necessary information to a an `impl` block to register the properties and methods with Godot.
 ///

gdnative-derive/src/methods.rs

@@ -7,58 +7,13 @@ use proc_macro2::TokenStream as TokenStream2;
 use quote::{quote, ToTokens};
 use std::boxed::Box;
 
+use crate::syntax::rpc_mode::RpcMode;
 use crate::utils::find_non_concrete;
 
 use self::mixin_args::{MixinArgsBuilder, MixinKind};
 
 mod mixin_args;
 
-#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug)]
-pub enum RpcMode {
-    Disabled,
-    Remote,
-    RemoteSync,
-    Master,
-    Puppet,
-    MasterSync,
-    PuppetSync,
-}
-
-impl RpcMode {
-    fn parse(s: &str) -> Option<Self> {
-        match s {
-            "remote" => Some(RpcMode::Remote),
-            "remote_sync" => Some(RpcMode::RemoteSync),
-            "master" => Some(RpcMode::Master),
-            "puppet" => Some(RpcMode::Puppet),
-            "disabled" => Some(RpcMode::Disabled),
-            "master_sync" => Some(RpcMode::MasterSync),
-            "puppet_sync" => Some(RpcMode::PuppetSync),
-            _ => None,
-        }
-    }
-}
-
-impl Default for RpcMode {
-    fn default() -> Self {
-        RpcMode::Disabled
-    }
-}
-
-impl ToTokens for RpcMode {
-    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
-        match self {
-            RpcMode::Disabled => tokens.extend(quote!(RpcMode::Disabled)),
-            RpcMode::Remote => tokens.extend(quote!(RpcMode::Remote)),
-            RpcMode::RemoteSync => tokens.extend(quote!(RpcMode::RemoteSync)),
-            RpcMode::Master => tokens.extend(quote!(RpcMode::Master)),
-            RpcMode::Puppet => tokens.extend(quote!(RpcMode::Puppet)),
-            RpcMode::MasterSync => tokens.extend(quote!(RpcMode::MasterSync)),
-            RpcMode::PuppetSync => tokens.extend(quote!(RpcMode::PuppetSync)),
-        }
-    }
-}
-
 pub(crate) struct ClassMethodExport {
     pub(crate) class_ty: Box<Type>,
     pub(crate) methods: Vec<ExportMethod>,

gdnative-derive/src/native_script/mod.rs

@@ -100,6 +100,8 @@ pub(crate) fn derive_native_class(derive_input: &DeriveInput) -> Result<TokenStr
                     .map(|default_value| quote!(.with_default(#default_value)));
                 let with_hint = config.hint.map(|hint_fn| quote!(.with_hint(#hint_fn())));
                 let with_usage = config.no_editor.then(|| quote!(.with_usage(#gdnative_core::export::PropertyUsage::NOEDITOR)));
+                let with_rpc_mode = config.rpc_mode.map(|rpc_mode| quote!(.with_rpc_mode(#gdnative_core::export::#rpc_mode)));
+
                 // check whether this property type is `Property<T>`. if so, extract T from it.
                 let property_ty = match config.ty {
                     Type::Path(ref path) => path
@@ -176,6 +178,7 @@ pub(crate) fn derive_native_class(derive_input: &DeriveInput) -> Result<TokenStr
                         #with_default
                         #with_hint
                         #with_usage
+                        #with_rpc_mode
                         #with_getter
                         #with_setter
                         .done();

gdnative-derive/src/native_script/property_args.rs

@@ -2,6 +2,8 @@ use proc_macro2::Span;
 use std::fmt::Debug;
 use syn::spanned::Spanned;
 
+use crate::syntax::rpc_mode::RpcMode;
+
 #[derive(Debug)]
 pub enum PropertyGet {
     Default,
@@ -22,6 +24,7 @@ pub struct PropertyAttrArgs {
     pub hint: Option<syn::Path>,
     pub get: Option<PropertyGet>,
     pub set: Option<PropertySet>,
+    pub rpc_mode: Option<RpcMode>,
     pub no_editor: bool,
 }
 
@@ -32,6 +35,7 @@ pub struct PropertyAttrArgsBuilder {
     hint: Option<syn::Path>,
     get: Option<PropertyGet>,
     set: Option<PropertySet>,
+    rpc_mode: Option<RpcMode>,
     no_editor: bool,
 }
 
@@ -44,6 +48,7 @@ impl PropertyAttrArgsBuilder {
             hint: None,
             get: None,
             set: None,
+            rpc_mode: None,
             no_editor: false,
         }
     }
@@ -125,6 +130,18 @@ impl PropertyAttrArgsBuilder {
             "get" => process_path_input!(get, PropertyGet::Owned),
             "get_ref" => process_path_input!(get, PropertyGet::Ref),
             "set" => process_path_input!(set, PropertySet::WithPath),
+            "rpc" => {
+                let rpc = Self::extract_lit_str(&pair.lit)
+                    .ok_or_else(|| Self::err_attr_not_a_string_literal(pair.span(), "rpc"))?;
+                let rpc = rpc.value();
+                let rpc = RpcMode::parse(&rpc).ok_or_else(|| {
+                    syn::Error::new(
+                        pair.lit.span(),
+                        format!("unexpected value for `rpc`: {rpc}"),
+                    )
+                })?;
+                update_prop!(rpc_mode, rpc)
+            }
             _ => {
                 return Err(syn::Error::new(
                     pair.span(),
@@ -167,6 +184,7 @@ impl PropertyAttrArgsBuilder {
             hint: self.hint,
             get: self.get,
             set: self.set,
+            rpc_mode: self.rpc_mode,
             no_editor: self.no_editor,
         }
     }

gdnative-derive/src/syntax.rs

@@ -0,0 +1 @@
+pub mod rpc_mode;

gdnative-derive/src/syntax/rpc_mode.rs

@@ -0,0 +1,47 @@
+use quote::{quote, ToTokens};
+
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug)]
+pub enum RpcMode {
+    Disabled,
+    Remote,
+    RemoteSync,
+    Master,
+    Puppet,
+    MasterSync,
+    PuppetSync,
+}
+
+impl RpcMode {
+    pub fn parse(s: &str) -> Option<Self> {
+        match s {
+            "remote" => Some(RpcMode::Remote),
+            "remote_sync" => Some(RpcMode::RemoteSync),
+            "master" => Some(RpcMode::Master),
+            "puppet" => Some(RpcMode::Puppet),
+            "disabled" => Some(RpcMode::Disabled),
+            "master_sync" => Some(RpcMode::MasterSync),
+            "puppet_sync" => Some(RpcMode::PuppetSync),
+            _ => None,
+        }
+    }
+}
+
+impl Default for RpcMode {
+    fn default() -> Self {
+        RpcMode::Disabled
+    }
+}
+
+impl ToTokens for RpcMode {
+    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
+        match self {
+            RpcMode::Disabled => tokens.extend(quote!(RpcMode::Disabled)),
+            RpcMode::Remote => tokens.extend(quote!(RpcMode::Remote)),
+            RpcMode::RemoteSync => tokens.extend(quote!(RpcMode::RemoteSync)),
+            RpcMode::Master => tokens.extend(quote!(RpcMode::Master)),
+            RpcMode::Puppet => tokens.extend(quote!(RpcMode::Puppet)),
+            RpcMode::MasterSync => tokens.extend(quote!(RpcMode::MasterSync)),
+            RpcMode::PuppetSync => tokens.extend(quote!(RpcMode::PuppetSync)),
+        }
+    }
+}