minor: improve readability

naming, layout & comments help!

crates/proc_macro_api/src/lib.rs

@@ -26,58 +26,10 @@
 };
 pub use version::{read_dylib_info, RustCInfo};
 
-#[derive(Debug, Clone)]
-pub struct ProcMacroProcessExpander {
-    process: Arc<Mutex<ProcMacroProcessSrv>>,
-    dylib_path: AbsPathBuf,
-    name: SmolStr,
-    kind: ProcMacroKind,
-}
-
-impl Eq for ProcMacroProcessExpander {}
-impl PartialEq for ProcMacroProcessExpander {
-    fn eq(&self, other: &Self) -> bool {
-        self.name == other.name
-            && self.kind == other.kind
-            && self.dylib_path == other.dylib_path
-            && Arc::ptr_eq(&self.process, &other.process)
-    }
-}
-
-impl ProcMacroProcessExpander {
-    pub fn name(&self) -> &str {
-        &self.name
-    }
-
-    pub fn kind(&self) -> ProcMacroKind {
-        self.kind
-    }
-
-    pub fn expand(
-        &self,
-        subtree: &Subtree,
-        attr: Option<&Subtree>,
-        env: Vec<(String, String)>,
-    ) -> Result<Subtree, tt::ExpansionError> {
-        let task = ExpansionTask {
-            macro_body: FlatTree::new(subtree),
-            macro_name: self.name.to_string(),
-            attributes: attr.map(FlatTree::new),
-            lib: self.dylib_path.to_path_buf().into(),
-            env,
-        };
-
-        let result: ExpansionResult = self
-            .process
-            .lock()
-            .unwrap_or_else(|e| e.into_inner())
-            .send_task(msg::Request::ExpansionMacro(task))?;
-        Ok(result.expansion.to_subtree())
-    }
-}
-
+/// A handle to an external process which load dylibs with macros (.so or .dll)
+/// and runs actual macro expansion functions.
 #[derive(Debug)]
-pub struct ProcMacroClient {
+pub struct ProcMacroServer {
     /// Currently, the proc macro process expands all procedural macros sequentially.
     ///
     /// That means that concurrent salsa requests may block each other when expanding proc macros,
@@ -87,17 +39,39 @@ pub struct ProcMacroClient {
     process: Arc<Mutex<ProcMacroProcessSrv>>,
 }
 
-impl ProcMacroClient {
+/// A handle to a specific macro (a `#[proc_macro]` annotated function).
+///
+/// It exists withing a context of a specific [`ProcMacroProcess`] -- currently
+/// we share a single expander process for all macros.
+#[derive(Debug, Clone)]
+pub struct ProcMacro {
+    process: Arc<Mutex<ProcMacroProcessSrv>>,
+    dylib_path: AbsPathBuf,
+    name: SmolStr,
+    kind: ProcMacroKind,
+}
+
+impl Eq for ProcMacro {}
+impl PartialEq for ProcMacro {
+    fn eq(&self, other: &Self) -> bool {
+        self.name == other.name
+            && self.kind == other.kind
+            && self.dylib_path == other.dylib_path
+            && Arc::ptr_eq(&self.process, &other.process)
+    }
+}
+
+impl ProcMacroServer {
     /// Spawns an external process as the proc macro server and returns a client connected to it.
-    pub fn extern_process(
+    pub fn spawn(
         process_path: AbsPathBuf,
         args: impl IntoIterator<Item = impl AsRef<OsStr>>,
-    ) -> io::Result<ProcMacroClient> {
+    ) -> io::Result<ProcMacroServer> {
         let process = ProcMacroProcessSrv::run(process_path, args)?;
-        Ok(ProcMacroClient { process: Arc::new(Mutex::new(process)) })
+        Ok(ProcMacroServer { process: Arc::new(Mutex::new(process)) })
     }
 
-    pub fn by_dylib_path(&self, dylib_path: &AbsPath) -> Vec<ProcMacroProcessExpander> {
+    pub fn load_dylib(&self, dylib_path: &AbsPath) -> Vec<ProcMacro> {
         let _p = profile::span("ProcMacroClient::by_dylib_path");
         match version::read_dylib_info(dylib_path) {
             Ok(info) => {
@@ -129,7 +103,7 @@ pub fn by_dylib_path(&self, dylib_path: &AbsPath) -> Vec<ProcMacroProcessExpande
 
         macros
             .into_iter()
-            .map(|(name, kind)| ProcMacroProcessExpander {
+            .map(|(name, kind)| ProcMacro {
                 process: self.process.clone(),
                 name: name.into(),
                 kind,
@@ -138,3 +112,35 @@ pub fn by_dylib_path(&self, dylib_path: &AbsPath) -> Vec<ProcMacroProcessExpande
             .collect()
     }
 }
+
+impl ProcMacro {
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn kind(&self) -> ProcMacroKind {
+        self.kind
+    }
+
+    pub fn expand(
+        &self,
+        subtree: &Subtree,
+        attr: Option<&Subtree>,
+        env: Vec<(String, String)>,
+    ) -> Result<Subtree, tt::ExpansionError> {
+        let task = ExpansionTask {
+            macro_body: FlatTree::new(subtree),
+            macro_name: self.name.to_string(),
+            attributes: attr.map(FlatTree::new),
+            lib: self.dylib_path.to_path_buf().into(),
+            env,
+        };
+
+        let result: ExpansionResult = self
+            .process
+            .lock()
+            .unwrap_or_else(|e| e.into_inner())
+            .send_task(msg::Request::ExpansionMacro(task))?;
+        Ok(result.expansion.to_subtree())
+    }
+}

crates/rust-analyzer/src/cli/load_cargo.rs

@@ -7,7 +7,7 @@
 use hir::db::DefDatabase;
 use ide::{AnalysisHost, Change};
 use ide_db::base_db::CrateGraph;
-use proc_macro_api::ProcMacroClient;
+use proc_macro_api::ProcMacroServer;
 use project_model::{CargoConfig, ProjectManifest, ProjectWorkspace};
 use vfs::{loader::Handle, AbsPath, AbsPathBuf};
 
@@ -28,7 +28,7 @@ pub fn load_workspace_at(
     cargo_config: &CargoConfig,
     load_config: &LoadCargoConfig,
     progress: &dyn Fn(String),
-) -> Result<(AnalysisHost, vfs::Vfs, Option<ProcMacroClient>)> {
+) -> Result<(AnalysisHost, vfs::Vfs, Option<ProcMacroServer>)> {
     let root = AbsPathBuf::assert(std::env::current_dir()?.join(root));
     let root = ProjectManifest::discover_single(&root)?;
     let mut workspace = ProjectWorkspace::load(root, cargo_config, progress)?;
@@ -49,7 +49,7 @@ pub fn load_workspace_at(
 pub fn load_workspace(
     ws: ProjectWorkspace,
     load_config: &LoadCargoConfig,
-) -> Result<(AnalysisHost, vfs::Vfs, Option<ProcMacroClient>)> {
+) -> Result<(AnalysisHost, vfs::Vfs, Option<ProcMacroServer>)> {
     let (sender, receiver) = unbounded();
     let mut vfs = vfs::Vfs::default();
     let mut loader = {
@@ -60,7 +60,7 @@ pub fn load_workspace(
 
     let proc_macro_client = if load_config.with_proc_macro {
         let path = AbsPathBuf::assert(std::env::current_exe()?);
-        Some(ProcMacroClient::extern_process(path, &["proc-macro"]).unwrap())
+        Some(ProcMacroServer::spawn(path, &["proc-macro"]).unwrap())
     } else {
         None
     };

crates/rust-analyzer/src/global_state.rs

@@ -11,7 +11,7 @@
 use ide_db::base_db::CrateId;
 use lsp_types::{SemanticTokens, Url};
 use parking_lot::{Mutex, RwLock};
-use proc_macro_api::ProcMacroClient;
+use proc_macro_api::ProcMacroServer;
 use project_model::{CargoWorkspace, ProjectWorkspace, Target, WorkspaceBuildScripts};
 use rustc_hash::FxHashMap;
 use vfs::AnchoredPathBuf;
@@ -60,7 +60,7 @@ pub(crate) struct GlobalState {
     pub(crate) shutdown_requested: bool,
     pub(crate) last_reported_status: Option<lsp_ext::ServerStatusParams>,
     pub(crate) source_root_config: SourceRootConfig,
-    pub(crate) proc_macro_client: Option<ProcMacroClient>,
+    pub(crate) proc_macro_client: Option<ProcMacroServer>,
 
     pub(crate) flycheck: Vec<FlycheckHandle>,
     pub(crate) flycheck_sender: Sender<flycheck::Message>,

crates/rust-analyzer/src/reload.rs

@@ -7,7 +7,7 @@
 use ide_db::base_db::{
     CrateGraph, Env, ProcMacro, ProcMacroExpander, ProcMacroKind, SourceRoot, VfsPath,
 };
-use proc_macro_api::ProcMacroClient;
+use proc_macro_api::ProcMacroServer;
 use project_model::{ProjectWorkspace, WorkspaceBuildScripts};
 use vfs::{file_set::FileSetConfig, AbsPath, AbsPathBuf, ChangeKind};
 
@@ -329,7 +329,7 @@ fn eq_ignore_build_data<'a>(
         if self.proc_macro_client.is_none() {
             self.proc_macro_client = match self.config.proc_macro_srv() {
                 None => None,
-                Some((path, args)) => match ProcMacroClient::extern_process(path.clone(), args) {
+                Some((path, args)) => match ProcMacroServer::spawn(path.clone(), args) {
                     Ok(it) => Some(it),
                     Err(err) => {
                         tracing::error!(
@@ -556,15 +556,15 @@ pub(crate) fn partition(&self, vfs: &vfs::Vfs) -> Vec<SourceRoot> {
     }
 }
 
-pub(crate) fn load_proc_macro(client: Option<&ProcMacroClient>, path: &AbsPath) -> Vec<ProcMacro> {
+pub(crate) fn load_proc_macro(client: Option<&ProcMacroServer>, path: &AbsPath) -> Vec<ProcMacro> {
     return client
-        .map(|it| it.by_dylib_path(path))
+        .map(|it| it.load_dylib(path))
         .unwrap_or_default()
         .into_iter()
         .map(expander_to_proc_macro)
         .collect();
 
-    fn expander_to_proc_macro(expander: proc_macro_api::ProcMacroProcessExpander) -> ProcMacro {
+    fn expander_to_proc_macro(expander: proc_macro_api::ProcMacro) -> ProcMacro {
         let name = expander.name().into();
         let kind = match expander.kind() {
             proc_macro_api::ProcMacroKind::CustomDerive => ProcMacroKind::CustomDerive,
@@ -576,7 +576,7 @@ fn expander_to_proc_macro(expander: proc_macro_api::ProcMacroProcessExpander) ->
     }
 
     #[derive(Debug)]
-    struct Expander(proc_macro_api::ProcMacroProcessExpander);
+    struct Expander(proc_macro_api::ProcMacro);
 
     impl ProcMacroExpander for Expander {
         fn expand(