Reorganize proc-macro-srv more, add --format and --version args

crates/load-cargo/src/lib.rs

@@ -533,7 +533,7 @@ impl ProcMacroExpander for Expander {
             current_dir,
         ) {
             Ok(Ok(subtree)) => Ok(subtree),
-            Ok(Err(err)) => Err(ProcMacroExpansionError::Panic(err.0)),
+            Ok(Err(err)) => Err(ProcMacroExpansionError::Panic(err)),
             Err(err) => Err(ProcMacroExpansionError::System(err.to_string())),
         }
     }

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

@@ -0,0 +1,172 @@
+//! The initial proc-macro-srv protocol, soon to be deprecated.
+
+pub mod json;
+pub mod msg;
+
+use std::{
+    io::{BufRead, Write},
+    sync::Arc,
+};
+
+use paths::AbsPath;
+use span::Span;
+
+use crate::{
+    ProcMacro, ProcMacroKind, ServerError,
+    legacy_protocol::{
+        json::{read_json, write_json},
+        msg::{
+            ExpandMacro, ExpandMacroData, ExpnGlobals, FlatTree, Message, Request, Response,
+            ServerConfig, SpanDataIndexMap, deserialize_span_data_index_map,
+            flat::serialize_span_data_index_map,
+        },
+    },
+    process::ProcMacroServerProcess,
+    version,
+};
+
+pub(crate) use crate::legacy_protocol::msg::SpanMode;
+
+/// Legacy span type, only defined here as it is still used by the proc-macro server.
+/// While rust-analyzer doesn't use this anymore at all, RustRover relies on the legacy type for
+/// proc-macro expansion.
+#[derive(Clone, Copy, PartialEq, Eq, Hash)]
+pub struct SpanId(pub u32);
+
+impl std::fmt::Debug for SpanId {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+pub(crate) fn version_check(srv: &ProcMacroServerProcess) -> Result<u32, ServerError> {
+    let request = Request::ApiVersionCheck {};
+    let response = send_task(srv, request)?;
+
+    match response {
+        Response::ApiVersionCheck(version) => Ok(version),
+        _ => Err(ServerError { message: "unexpected response".to_owned(), io: None }),
+    }
+}
+
+/// Enable support for rust-analyzer span mode if the server supports it.
+pub(crate) fn enable_rust_analyzer_spans(
+    srv: &ProcMacroServerProcess,
+) -> Result<SpanMode, ServerError> {
+    let request = Request::SetConfig(ServerConfig { span_mode: SpanMode::RustAnalyzer });
+    let response = send_task(srv, request)?;
+
+    match response {
+        Response::SetConfig(ServerConfig { span_mode }) => Ok(span_mode),
+        _ => Err(ServerError { message: "unexpected response".to_owned(), io: None }),
+    }
+}
+
+/// Finds proc-macros in a given dynamic library.
+pub(crate) fn find_proc_macros(
+    srv: &ProcMacroServerProcess,
+    dylib_path: &AbsPath,
+) -> Result<Result<Vec<(String, ProcMacroKind)>, String>, ServerError> {
+    let request = Request::ListMacros { dylib_path: dylib_path.to_path_buf().into() };
+
+    let response = send_task(srv, request)?;
+
+    match response {
+        Response::ListMacros(it) => Ok(it),
+        _ => Err(ServerError { message: "unexpected response".to_owned(), io: None }),
+    }
+}
+
+pub(crate) fn expand(
+    proc_macro: &ProcMacro,
+    subtree: tt::SubtreeView<'_, Span>,
+    attr: Option<tt::SubtreeView<'_, Span>>,
+    env: Vec<(String, String)>,
+    def_site: Span,
+    call_site: Span,
+    mixed_site: Span,
+    current_dir: String,
+) -> Result<Result<tt::TopSubtree<span::SpanData<span::SyntaxContext>>, String>, crate::ServerError>
+{
+    let version = proc_macro.process.version();
+    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 {
+        data: ExpandMacroData {
+            macro_body: FlatTree::new(subtree, version, &mut span_data_table),
+            macro_name: proc_macro.name.to_string(),
+            attributes: attr.map(|subtree| FlatTree::new(subtree, version, &mut span_data_table)),
+            has_global_spans: ExpnGlobals {
+                serialize: version >= version::HAS_GLOBAL_SPANS,
+                def_site,
+                call_site,
+                mixed_site,
+            },
+            span_data_table: if proc_macro.process.rust_analyzer_spans() {
+                serialize_span_data_index_map(&span_data_table)
+            } else {
+                Vec::new()
+            },
+        },
+        lib: proc_macro.dylib_path.to_path_buf().into(),
+        env,
+        current_dir: Some(current_dir),
+    };
+
+    let response = send_task(&proc_macro.process, Request::ExpandMacro(Box::new(task)))?;
+
+    match response {
+        Response::ExpandMacro(it) => Ok(it
+            .map(|tree| {
+                let mut expanded = FlatTree::to_subtree_resolved(tree, version, &span_data_table);
+                if proc_macro.needs_fixup_change() {
+                    proc_macro.change_fixup_to_match_old_server(&mut expanded);
+                }
+                expanded
+            })
+            .map_err(|msg| msg.0)),
+        Response::ExpandMacroExtended(it) => Ok(it
+            .map(|resp| {
+                let mut expanded = FlatTree::to_subtree_resolved(
+                    resp.tree,
+                    version,
+                    &deserialize_span_data_index_map(&resp.span_data_table),
+                );
+                if proc_macro.needs_fixup_change() {
+                    proc_macro.change_fixup_to_match_old_server(&mut expanded);
+                }
+                expanded
+            })
+            .map_err(|msg| msg.0)),
+        _ => Err(ServerError { message: "unexpected response".to_owned(), io: None }),
+    }
+}
+
+/// Sends a request to the proc-macro server and waits for a response.
+fn send_task(srv: &ProcMacroServerProcess, req: Request) -> Result<Response, ServerError> {
+    if let Some(server_error) = srv.exited() {
+        return Err(server_error.clone());
+    }
+
+    srv.send_task(send_request, req)
+}
+
+/// Sends a request to the server and reads the response.
+fn send_request(
+    mut writer: &mut dyn Write,
+    mut reader: &mut dyn BufRead,
+    req: Request,
+    buf: &mut String,
+) -> Result<Option<Response>, ServerError> {
+    req.write(write_json, &mut writer).map_err(|err| ServerError {
+        message: "failed to write request".into(),
+        io: Some(Arc::new(err)),
+    })?;
+    let res = Response::read(read_json, &mut reader, buf).map_err(|err| ServerError {
+        message: "failed to read response".into(),
+        io: Some(Arc::new(err)),
+    })?;
+    Ok(res)
+}