feat(macros): add support for rename command macro in tauri-macros #14173 (#14473)

* feat(macros): add support for alias command macro in tauri-macros #14173

* feat(macro): rename alias command to improve clarity in tauri-macros

* feat(wrapper): refactor rename handling in WrapperAttributes for improved clarity

* feat(wrapper): update rename policy to use TokenStream2 for improved flexibility

* feat(handler): streamline command definition parsing for improved efficiency

* feat(wrapper): simplify macro export logic in wrapper function for clarity

* fix(handler): optimize command zipping for improved readability

* fix: code style compectiable with rust 1.77.2

* fix const not in scope when command is defined in another mod

* update examples

* update change file

* fmt

* style: fix pnpm:check errors

---------

Co-authored-by: Lucas Nogueira <lucas@tauri.app>

.changes/add-macros-allow-rename-command.md

@@ -0,0 +1,6 @@
+---
+"tauri-macros": minor:feat
+"tauri": minor:feat
+---
+
+Add support for the `rename` attribute in the `tauri::command` macro to allow renaming the command to something other than the function name.

crates/tauri-macros/src/command/handler.rs

@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: Apache-2.0
 // SPDX-License-Identifier: MIT
 
-use quote::format_ident;
+use quote::{format_ident, quote};
 use syn::{
   parse::{Parse, ParseBuffer, ParseStream},
   Attribute, Ident, Path, Token,
@@ -151,14 +151,30 @@ impl From<Handler> for proc_macro::TokenStream {
   ) -> Self {
     let cmd = format_ident!("__tauri_cmd__");
     let invoke = format_ident!("__tauri_invoke__");
-    let (paths, attrs): (Vec<Path>, Vec<Vec<Attribute>>) = command_defs
-      .into_iter()
-      .map(|def| (def.path, def.attrs))
-      .unzip();
+    let mut paths: Vec<Path> = Vec::new();
+    let mut attrs: Vec<Vec<Attribute>> = Vec::new();
+    let mut command_name_macros: Vec<proc_macro2::TokenStream> = Vec::new();
+    for (def, command) in command_defs.into_iter().zip(commands) {
+      let path = def.path;
+      let attrs_vec = def.attrs;
+
+      let mut command_name_macro_path = path.clone();
+      let last = command_name_macro_path
+        .segments
+        .last_mut()
+        .expect("path has at least one segment");
+      last.ident = format_ident!("__tauri_command_name_{command}");
+
+      paths.push(path);
+      attrs.push(attrs_vec);
+      // Call the macro to get the command name string literal
+      command_name_macros.push(quote!(#command_name_macro_path!()));
+    }
+
     quote::quote!(move |#invoke| {
       let #cmd = #invoke.message.command();
       match #cmd {
-        #(#(#attrs)* stringify!(#commands) => #wrappers!(#paths, #invoke),)*
+        #(#(#attrs)* #command_name_macros => #wrappers!(#paths, #invoke),)*
         _ => {
           return false;
         },

crates/tauri-macros/src/command/wrapper.rs

@@ -40,6 +40,7 @@ struct WrapperAttributes {
   root: TokenStream2,
   execution_context: ExecutionContext,
   argument_case: ArgumentCase,
+  rename: RenamePolicy,
 }
 
 impl Parse for WrapperAttributes {
@@ -48,6 +49,7 @@ impl Parse for WrapperAttributes {
       root: quote!(::tauri),
       execution_context: ExecutionContext::Blocking,
       argument_case: ArgumentCase::Camel,
+      rename: RenamePolicy::Keep,
     };
 
     let attrs = Punctuated::<WrapperAttributeKind, Token![,]>::parse_terminated(input)?;
@@ -74,6 +76,19 @@ impl Parse for WrapperAttributes {
                 }
               };
             }
+          } else if v.path.is_ident("rename") {
+            if let Expr::Lit(ExprLit {
+              lit: Lit::Str(s), ..
+            }) = v.value
+            {
+              let lit = s.value();
+              wrapper_attributes.rename = RenamePolicy::Rename(quote!(#lit));
+            } else {
+              return Err(syn::Error::new(
+                v.span(),
+                "expected string literal for rename",
+              ));
+            }
           } else if v.path.is_ident("root") {
             if let Expr::Lit(ExprLit {
               lit: Lit::Str(s),
@@ -94,7 +109,7 @@ impl Parse for WrapperAttributes {
         WrapperAttributeKind::Meta(Meta::Path(_)) => {
           return Err(syn::Error::new(
             input.span(),
-            "unexpected input, expected one of `rename_all`, `root`, `async`",
+            "unexpected input, expected one of `rename_all`, `rename`, `root`, `async`",
           ));
         }
         WrapperAttributeKind::Async => {
@@ -120,6 +135,12 @@ enum ArgumentCase {
   Camel,
 }
 
+/// The rename policy for the command.
+enum RenamePolicy {
+  Keep,
+  Rename(TokenStream2),
+}
+
 /// The bindings we attach to `tauri::Invoke`.
 struct Invoke {
   message: Ident,
@@ -138,9 +159,11 @@ pub fn wrapper(attributes: TokenStream, item: TokenStream) -> TokenStream {
     attrs.execution_context = ExecutionContext::Async;
   }
 
-  // macros used with `pub use my_macro;` need to be exported with `#[macro_export]`
+  // macros used with `pub use my_macro;` need to be exported with `#[macro_export]`.
   let maybe_macro_export = match &function.vis {
-    Visibility::Public(_) | Visibility::Restricted(_) => quote!(#[macro_export]),
+    Visibility::Public(_) | Visibility::Restricted(_) => {
+      quote!(#[macro_export])
+    }
     _ => TokenStream2::default(),
   };
 
@@ -270,6 +293,17 @@ pub fn wrapper(attributes: TokenStream, item: TokenStream) -> TokenStream {
     TokenStream2::default()
   };
 
+  // Always define a hidden macro that returns the externally invoked command name.
+  // This lets the handler match on the renamed string while the original function
+  // identifier remains usable in `generate_handler![original_fn_name]`.
+  let command_name_macro_ident = format_ident!("__tauri_command_name_{}", function.sig.ident);
+  let command_name_value = if let RenamePolicy::Rename(ref rename) = attrs.rename {
+    quote!(#rename)
+  } else {
+    let ident = &function.sig.ident;
+    quote!(stringify!(#ident))
+  };
+
   // Rely on rust 2018 edition to allow importing a macro from a path.
   quote!(
     #async_command_check
@@ -277,6 +311,17 @@ pub fn wrapper(attributes: TokenStream, item: TokenStream) -> TokenStream {
     #maybe_allow_unused
     #function
 
+    // Command name macro used by the handler for pattern matching.
+    // This macro returns the command name string literal (renamed or original).
+    #maybe_allow_unused
+    #maybe_macro_export
+    #[doc(hidden)]
+    macro_rules! #command_name_macro_ident {
+      () => {
+        #command_name_value
+      };
+    }
+
     #maybe_allow_unused
     #maybe_macro_export
     #[doc(hidden)]
@@ -303,7 +348,7 @@ pub fn wrapper(attributes: TokenStream, item: TokenStream) -> TokenStream {
 
     // allow the macro to be resolved with the same path as the command function
     #[allow(unused_imports)]
-    #visibility use #wrapper;
+    #visibility use {#wrapper, #command_name_macro_ident};
   )
   .into()
 }
@@ -467,11 +512,16 @@ fn parse_arg(
   }
 
   let root = &attributes.root;
+  let command_name = if let RenamePolicy::Rename(r) = &attributes.rename {
+    quote!(stringify!(#r))
+  } else {
+    quote!(stringify!(#command))
+  };
 
   Ok(quote!(#root::ipc::CommandArg::from_command(
     #root::ipc::CommandItem {
       plugin: #plugin_name,
-      name: stringify!(#command),
+      name: #command_name,
       key: #key,
       message: &#message,
       acl: &#acl,

examples/commands/commands.rs

@@ -25,3 +25,8 @@ pub fn simple_command(the_argument: String) {
 pub fn stateful_command(the_argument: Option<String>, state: State<'_, super::MyState>) {
   println!("{:?} {:?}", the_argument, state.inner());
 }
+
+#[command(rename = "renamed_command_in_mod_new")]
+pub fn renamed_command_in_mod() {
+  println!("renamed command in mod called");
+}

examples/commands/index.html

@@ -63,7 +63,11 @@
         {
           name: 'command_arguments_tuple_struct',
           args: { inlinePerson: ['ferris', 6] }
-        }
+        },
+        { name: 'renamed_command' },
+        { name: 'renamed_command_new' },
+        { name: 'renamed_command_in_mod' },
+        { name: 'renamed_command_in_mod_new' }
       ]
 
       for (const command of commands) {

examples/commands/main.rs

@@ -6,7 +6,7 @@
 
 // we move some basic commands to a separate module just to show it works
 mod commands;
-use commands::{cmd, invoke, message, resolver};
+use commands::{cmd, invoke, message, renamed_command_in_mod, resolver};
 
 use serde::Deserialize;
 use tauri::{
@@ -188,6 +188,11 @@ fn command_arguments_wild(_: Window) {
   println!("we saw the wildcard!")
 }
 
+#[command(rename = "renamed_command_new")]
+fn renamed_command() {
+  println!("renamed command called")
+}
+
 #[derive(Deserialize)]
 struct Person<'a> {
   name: &'a str,
@@ -246,6 +251,8 @@ fn main() {
       future_simple_command,
       async_stateful_command,
       command_arguments_wild,
+      renamed_command,
+      renamed_command_in_mod,
       command_arguments_struct,
       simple_command_with_result,
       async_simple_command_snake,