Auto merge of rust-lang#17520 - Veykril:slim-proc-macro-api, r=Veykril

internal: Cleanup proc-macro-srv some more

crates/base-db/src/lib.rs

@@ -1,7 +1,5 @@
 //! base_db defines basic database traits. The concrete DB is defined by ide.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 mod change;
 mod input;
 

crates/cfg/src/lib.rs

@@ -1,7 +1,5 @@
 //! cfg defines conditional compiling options, `cfg` attribute parser and evaluator
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 mod cfg_expr;
 mod dnf;
 #[cfg(test)]

crates/flycheck/src/lib.rs

@@ -6,8 +6,6 @@
 // addition to `cargo check`. Either split it into 3 crates (one for test, one for check
 // and one common utilities) or change its name and docs to reflect the current state.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 use std::{fmt, io, process::Command, time::Duration};
 
 use crossbeam_channel::{never, select, unbounded, Receiver, Sender};

crates/hir-def/src/lib.rs

@@ -7,7 +7,6 @@
 //! Note that `hir_def` is a work in progress, so not all of the above is
 //! actually true.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
 #![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
 
 #[cfg(feature = "in-rust-tree")]

crates/hir-expand/src/lib.rs

@@ -4,7 +4,6 @@
 //! tree originates not from the text of some `FileId`, but from some macro
 //! expansion.
 #![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
-#![warn(rust_2018_idioms, unused_lifetimes)]
 
 pub mod attrs;
 pub mod builtin_attr_macro;

crates/hir-ty/src/lib.rs

@@ -1,6 +1,6 @@
 //! The type system. We currently use this to infer types for completion, hover
 //! information and various assists.
-#![warn(rust_2018_idioms, unused_lifetimes)]
+
 #![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
 
 #[cfg(feature = "in-rust-tree")]

crates/hir/src/lib.rs

@@ -17,7 +17,6 @@
 //! from the ide with completions, hovers, etc. It is a (soft, internal) boundary:
 //! <https://www.tedinski.com/2018/02/06/system-boundaries.html>.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
 #![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
 #![recursion_limit = "512"]
 

crates/ide-assists/src/lib.rs

@@ -58,8 +58,6 @@
 //! See also this post:
 //! <https://rust-analyzer.github.io/blog/2020/09/28/how-to-make-a-light-bulb.html>
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 mod assist_config;
 mod assist_context;
 #[cfg(test)]

crates/ide-completion/src/lib.rs

@@ -1,7 +1,5 @@
 //! `completions` crate provides utilities for generating completions of user input.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 mod completions;
 mod config;
 mod context;

crates/ide-db/src/lib.rs

@@ -2,8 +2,6 @@
 //!
 //! It is mainly a `HirDatabase` for semantic analysis, plus a `SymbolsDatabase`, for fuzzy search.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 mod apply_change;
 
 pub mod active_parameter;

crates/ide-diagnostics/src/lib.rs

@@ -23,8 +23,6 @@
 //! There are also a couple of ad-hoc diagnostics implemented directly here, we
 //! don't yet have a great pattern for how to do them properly.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 mod handlers {
     pub(crate) mod break_outside_of_loop;
     pub(crate) mod expected_function;

crates/ide-ssr/src/lib.rs

@@ -3,8 +3,6 @@
 //! Allows searching the AST for code that matches one or more patterns and then replacing that code
 //! based on a template.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 // Feature: Structural Search and Replace
 //
 // Search and replace with named wildcards that will match any expression, type, path, pattern or item.

crates/ide/src/lib.rs

@@ -8,7 +8,7 @@
 //! in this crate.
 
 // For proving that RootDatabase is RefUnwindSafe.
-#![warn(rust_2018_idioms, unused_lifetimes)]
+
 #![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
 #![recursion_limit = "128"]
 

crates/limit/src/lib.rs

@@ -1,7 +1,5 @@
 //! limit defines a struct to enforce limits.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 #[cfg(feature = "tracking")]
 use std::sync::atomic::AtomicUsize;
 

crates/mbe/src/lib.rs

@@ -6,8 +6,6 @@
 //! The tests for this functionality live in another crate:
 //! `hir_def::macro_expansion_tests::mbe`.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 mod expander;
 mod parser;
 mod syntax_bridge;

crates/parser/src/lib.rs

@@ -17,7 +17,6 @@
 //!
 //! [`Parser`]: crate::parser::Parser
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
 #![allow(rustdoc::private_intra_doc_links)]
 #![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
 

crates/paths/src/lib.rs

@@ -1,8 +1,6 @@
 //! Thin wrappers around `std::path`/`camino::path`, distinguishing between absolute and
 //! relative paths.
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
 use std::{
     borrow::Borrow,
     ffi::OsStr,

crates/proc-macro-api/Cargo.toml

@@ -15,7 +15,6 @@ doctest = false
 serde.workspace = true
 serde_json = { workspace = true, features = ["unbounded_depth"] }
 tracing.workspace = true
-triomphe.workspace = true
 rustc-hash.workspace = true
 indexmap.workspace = true
 

crates/proc-macro-api/src/json.rs

@@ -0,0 +1,35 @@
+//! Protocol functions for json.
+use std::io::{self, BufRead, Write};
+
+pub fn read_json<'a>(
+    inp: &mut impl BufRead,
+    buf: &'a mut String,
+) -> io::Result<Option<&'a String>> {
+    loop {
+        buf.clear();
+
+        inp.read_line(buf)?;
+        buf.pop(); // Remove trailing '\n'
+
+        if buf.is_empty() {
+            return Ok(None);
+        }
+
+        // Some ill behaved macro try to use stdout for debugging
+        // We ignore it here
+        if !buf.starts_with('{') {
+            tracing::error!("proc-macro tried to print : {}", buf);
+            continue;
+        }
+
+        return Ok(Some(buf));
+    }
+}
+
+pub fn write_json(out: &mut impl Write, msg: &str) -> io::Result<()> {
+    tracing::debug!("> {}", msg);
+    out.write_all(msg.as_bytes())?;
+    out.write_all(b"\n")?;
+    out.flush()?;
+    Ok(())
+}

crates/proc-macro-api/src/lib.rs

@@ -5,27 +5,23 @@
 //! is used to provide basic infrastructure for communication between two
 //! processes: Client (RA itself), Server (the external program)
 
-#![warn(rust_2018_idioms, unused_lifetimes)]
-
+pub mod json;
 pub mod msg;
 mod process;
 
 use base_db::Env;
-use indexmap::IndexSet;
 use paths::{AbsPath, AbsPathBuf};
-use rustc_hash::FxHashMap;
 use span::Span;
-use std::{
-    fmt, io,
-    sync::{Arc, Mutex},
-};
+use std::{fmt, io, sync::Arc};
+use tt::SmolStr;
 
 use serde::{Deserialize, Serialize};
 
 use crate::{
     msg::{
         deserialize_span_data_index_map, flat::serialize_span_data_index_map, ExpandMacro,
-        ExpnGlobals, FlatTree, PanicMessage, HAS_GLOBAL_SPANS, RUST_ANALYZER_SPAN_SUPPORT,
+        ExpnGlobals, FlatTree, PanicMessage, SpanDataIndexMap, HAS_GLOBAL_SPANS,
+        RUST_ANALYZER_SPAN_SUPPORT,
     },
     process::ProcMacroProcessSrv,
 };
@@ -48,9 +44,7 @@ pub struct ProcMacroServer {
     ///
     /// That means that concurrent salsa requests may block each other when expanding proc macros,
     /// which is unfortunate, but simple and good enough for the time being.
-    ///
-    /// Therefore, we just wrap the `ProcMacroProcessSrv` in a mutex here.
-    process: Arc<Mutex<ProcMacroProcessSrv>>,
+    process: Arc<ProcMacroProcessSrv>,
     path: AbsPathBuf,
 }
 
@@ -70,9 +64,9 @@ impl MacroDylib {
 /// we share a single expander process for all macros.
 #[derive(Debug, Clone)]
 pub struct ProcMacro {
-    process: Arc<Mutex<ProcMacroProcessSrv>>,
-    dylib_path: AbsPathBuf,
-    name: String,
+    process: Arc<ProcMacroProcessSrv>,
+    dylib_path: Arc<AbsPathBuf>,
+    name: SmolStr,
     kind: ProcMacroKind,
 }
 
@@ -81,15 +75,14 @@ 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.dylib_path, &other.dylib_path)
             && Arc::ptr_eq(&self.process, &other.process)
     }
 }
 
 #[derive(Clone, Debug)]
 pub struct ServerError {
     pub message: String,
-    // io::Error isn't Clone for some reason
     pub io: Option<Arc<io::Error>>,
 }
 
@@ -104,21 +97,15 @@ impl fmt::Display for ServerError {
     }
 }
 
-pub struct MacroPanic {
-    pub message: String,
-}
-
 impl ProcMacroServer {
     /// Spawns an external process as the proc macro server and returns a client connected to it.
     pub fn spawn(
         process_path: &AbsPath,
-        env: &FxHashMap<String, String>,
+        env: impl IntoIterator<Item = (impl AsRef<std::ffi::OsStr>, impl AsRef<std::ffi::OsStr>)>
+            + Clone,
     ) -> io::Result<ProcMacroServer> {
         let process = ProcMacroProcessSrv::run(process_path, env)?;
-        Ok(ProcMacroServer {
-            process: Arc::new(Mutex::new(process)),
-            path: process_path.to_owned(),
-        })
+        Ok(ProcMacroServer { process: Arc::new(process), path: process_path.to_owned() })
     }
 
     pub fn path(&self) -> &AbsPath {
@@ -127,17 +114,17 @@ impl ProcMacroServer {
 
     pub fn load_dylib(&self, dylib: MacroDylib) -> Result<Vec<ProcMacro>, ServerError> {
         let _p = tracing::info_span!("ProcMacroServer::load_dylib").entered();
-        let macros =
-            self.process.lock().unwrap_or_else(|e| e.into_inner()).find_proc_macros(&dylib.path)?;
+        let macros = self.process.find_proc_macros(&dylib.path)?;
 
+        let dylib_path = Arc::new(dylib.path);
         match macros {
             Ok(macros) => Ok(macros
                 .into_iter()
                 .map(|(name, kind)| ProcMacro {
                     process: self.process.clone(),
-                    name,
+                    name: name.into(),
                     kind,
-                    dylib_path: dylib.path.clone(),
+                    dylib_path: dylib_path.clone(),
                 })
                 .collect()),
             Err(message) => Err(ServerError { message, io: None }),
@@ -163,38 +150,37 @@ impl ProcMacro {
         call_site: Span,
         mixed_site: Span,
     ) -> Result<Result<tt::Subtree<Span>, PanicMessage>, ServerError> {
-        let version = self.process.lock().unwrap_or_else(|e| e.into_inner()).version();
+        let version = self.process.version();
         let current_dir = env.get("CARGO_MANIFEST_DIR");
 
-        let mut span_data_table = IndexSet::default();
+        let mut span_data_table = SpanDataIndexMap::default();
         let def_site = span_data_table.insert_full(def_site).0;
         let call_site = span_data_table.insert_full(call_site).0;
         let mixed_site = span_data_table.insert_full(mixed_site).0;
         let task = ExpandMacro {
-            macro_body: FlatTree::new(subtree, version, &mut span_data_table),
-            macro_name: self.name.to_string(),
-            attributes: attr.map(|subtree| FlatTree::new(subtree, version, &mut span_data_table)),
+            data: msg::ExpandMacroData {
+                macro_body: FlatTree::new(subtree, version, &mut span_data_table),
+                macro_name: self.name.to_string(),
+                attributes: attr
+                    .map(|subtree| FlatTree::new(subtree, version, &mut span_data_table)),
+                has_global_spans: ExpnGlobals {
+                    serialize: version >= HAS_GLOBAL_SPANS,
+                    def_site,
+                    call_site,
+                    mixed_site,
+                },
+                span_data_table: if version >= RUST_ANALYZER_SPAN_SUPPORT {
+                    serialize_span_data_index_map(&span_data_table)
+                } else {
+                    Vec::new()
+                },
+            },
             lib: self.dylib_path.to_path_buf().into(),
             env: env.into(),
             current_dir,
-            has_global_spans: ExpnGlobals {
-                serialize: version >= HAS_GLOBAL_SPANS,
-                def_site,
-                call_site,
-                mixed_site,
-            },
-            span_data_table: if version >= RUST_ANALYZER_SPAN_SUPPORT {
-                serialize_span_data_index_map(&span_data_table)
-            } else {
-                Vec::new()
-            },
         };
 
-        let response = self
-            .process
-            .lock()
-            .unwrap_or_else(|e| e.into_inner())
-            .send_task(msg::Request::ExpandMacro(Box::new(task)))?;
+        let response = self.process.send_task(msg::Request::ExpandMacro(Box::new(task)))?;
 
         match response {
             msg::Response::ExpandMacro(it) => {