Do not use the sysroot proc-macro server when a server path is given explicitly

Author: Veykril

crates/rust-analyzer/src/config.rs

@@ -7,7 +7,7 @@
 //! configure the server itself, feature flags are passed into analysis, and
 //! tweak things like automatic insertion of `()` in completions.
 
-use std::{ffi::OsString, fmt, iter, path::PathBuf};
+use std::{fmt, iter, path::PathBuf};
 
 use flycheck::FlycheckConfig;
 use ide::{
@@ -975,15 +975,17 @@ impl Config {
         self.data.lru_capacity
     }
 
-    pub fn proc_macro_srv(&self) -> Option<(AbsPathBuf, Vec<OsString>)> {
+    pub fn proc_macro_srv(&self) -> Option<(AbsPathBuf, /* is path explicitly set */ bool)> {
         if !self.data.procMacro_enable {
             return None;
         }
-        let path = match &self.data.procMacro_server {
-            Some(it) => self.root_path.join(it),
-            None => AbsPathBuf::assert(std::env::current_exe().ok()?),
-        };
-        Some((path, vec!["proc-macro".into()]))
+        Some(match &self.data.procMacro_server {
+            Some(it) => (
+                AbsPathBuf::try_from(it.clone()).unwrap_or_else(|path| self.root_path.join(path)),
+                true,
+            ),
+            None => (AbsPathBuf::assert(std::env::current_exe().ok()?), false),
+        })
     }
 
     pub fn dummy_replacements(&self) -> &FxHashMap<Box<str>, Box<[Box<str>]>> {

crates/rust-analyzer/src/reload.rs

@@ -306,41 +306,50 @@ impl GlobalState {
             format!("rust-analyzer-proc-macro-srv{}", std::env::consts::EXE_SUFFIX);
 
         if self.proc_macro_clients.is_empty() {
-            if let Some((path, args)) = self.config.proc_macro_srv() {
+            if let Some((path, path_manually_set)) = self.config.proc_macro_srv() {
                 tracing::info!("Spawning proc-macro servers");
                 self.proc_macro_clients = self
                     .workspaces
                     .iter()
                     .map(|ws| {
-                        let mut args = args.clone();
-                        let mut path = path.clone();
-
-                        if let ProjectWorkspace::Cargo { sysroot, .. }
-                        | ProjectWorkspace::Json { sysroot, .. } = ws
-                        {
-                            tracing::debug!("Found a cargo workspace...");
-                            if let Some(sysroot) = sysroot.as_ref() {
-                                tracing::debug!("Found a cargo workspace with a sysroot...");
-                                let server_path =
-                                    sysroot.root().join("libexec").join(&standalone_server_name);
-                                if std::fs::metadata(&server_path).is_ok() {
-                                    tracing::debug!(
-                                        "And the server exists at {}",
-                                        server_path.display()
-                                    );
-                                    path = server_path;
-                                    args = vec![];
-                                } else {
-                                    tracing::debug!(
-                                        "And the server does not exist at {}",
-                                        server_path.display()
-                                    );
+                        let (path, args) = if path_manually_set {
+                            tracing::debug!(
+                                "Pro-macro server path explicitly set: {}",
+                                path.display()
+                            );
+                            (path.clone(), vec![])
+                        } else {
+                            let mut sysroot_server = None;
+                            if let ProjectWorkspace::Cargo { sysroot, .. }
+                            | ProjectWorkspace::Json { sysroot, .. } = ws
+                            {
+                                if let Some(sysroot) = sysroot.as_ref() {
+                                    let server_path = sysroot
+                                        .root()
+                                        .join("libexec")
+                                        .join(&standalone_server_name);
+                                    if std::fs::metadata(&server_path).is_ok() {
+                                        tracing::debug!(
+                                            "Sysroot proc-macro server exists at {}",
+                                            server_path.display()
+                                        );
+                                        sysroot_server = Some(server_path);
+                                    } else {
+                                        tracing::debug!(
+                                            "Sysroot proc-macro server does not exist at {}",
+                                            server_path.display()
+                                        );
+                                    }
                                 }
                             }
-                        }
+                            sysroot_server.map_or_else(
+                                || (path.clone(), vec!["proc-macro".to_owned()]),
+                                |path| (path, vec![]),
+                            )
+                        };
 
                         tracing::info!(?args, "Using proc-macro server at {}", path.display(),);
-                        ProcMacroServer::spawn(path.clone(), args.clone()).map_err(|err| {
+                        ProcMacroServer::spawn(path.clone(), args).map_err(|err| {
                             let error = format!(
                                 "Failed to run proc-macro server from path {}, error: {:?}",
                                 path.display(),