Auto merge of rust-lang#12881 - Veykril:proc-srv, r=Veykril

fix: Fix server panicking on project loading when proc-macros are disabled

Fixes rust-lang/rust-analyzer#12879

Author: bors

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

@@ -66,7 +66,9 @@ pub fn load_workspace(
     };
 
     let crate_graph = ws.to_crate_graph(
-        &mut |_, path: &AbsPath| load_proc_macro(proc_macro_client.as_ref(), path, &[]),
+        &mut |_, path: &AbsPath| {
+            load_proc_macro(proc_macro_client.as_ref().map_err(|e| &**e), path, &[])
+        },
         &mut |path: &AbsPath| {
             let contents = loader.load_sync(path);
             let path = vfs::VfsPath::from(path.to_path_buf());

crates/rust-analyzer/src/reload.rs

@@ -390,7 +390,10 @@ impl GlobalState {
 
             let mut crate_graph = CrateGraph::default();
             for (idx, ws) in self.workspaces.iter().enumerate() {
-                let proc_macro_client = self.proc_macro_clients[idx].as_ref();
+                let proc_macro_client = match self.proc_macro_clients.get(idx) {
+                    Some(res) => res.as_ref().map_err(|e| &**e),
+                    None => Err("Proc macros are disabled"),
+                };
                 let mut load_proc_macro = move |crate_name: &str, path: &AbsPath| {
                     load_proc_macro(
                         proc_macro_client,
@@ -574,7 +577,7 @@ impl SourceRootConfig {
 /// Load the proc-macros for the given lib path, replacing all expanders whose names are in `dummy_replace`
 /// with an identity dummy expander.
 pub(crate) fn load_proc_macro(
-    server: Result<&ProcMacroServer, &String>,
+    server: Result<&ProcMacroServer, &str>,
     path: &AbsPath,
     dummy_replace: &[Box<str>],
 ) -> ProcMacroLoadResult {