From e06a7a3c81c8c0eb9214c536a4139e2b77f0f1ea Mon Sep 17 00:00:00 2001
From: Julian Hofer <julianhofer@gnome.org>
Date: Wed, 14 Feb 2024 21:31:57 +0100
Subject: [PATCH] Support analysis / types with Rust Analyzer

Fixes #881
It still takes a bit until diagnostics arrive, but this way error messages from `cargo` are included as well.
---
 src/langs/rust/rust.js | 8 ++++++--
 src/lsp/LSPClient.js   | 7 ++++---
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/src/langs/rust/rust.js b/src/langs/rust/rust.js
index 29bd494cb..2b5c046c8 100644
--- a/src/langs/rust/rust.js
+++ b/src/langs/rust/rust.js
@@ -22,8 +22,12 @@ export function setup({ document }) {
       code_view.handleDiagnostics(params.diagnostics);
     },
   );
-
-  lspc.start().catch(console.error);
+  const cacheDir = GLib.get_user_cache_dir();
+  const rustAnalyzerCache = `${cacheDir}/rust_analyzer_cache`;
+  // It shouldn't be necessary to disable `useRustcWrapper`, stop doing that as soon as that issue is fixed
+  // https://github.com/rust-lang/rust-analyzer/issues/16565#issuecomment-1944354758
+  const initializationOptions = {"cargo": {"buildScripts": {"useRustcWrapper": false}}, "rust": {"analyzerTargetDir": rustAnalyzerCache}};
+  lspc.start(initializationOptions).catch(console.error);
 
   buffer.connect("modified-changed", () => {
     if (!buffer.get_modified()) return;
diff --git a/src/lsp/LSPClient.js b/src/lsp/LSPClient.js
index d5207ac42..67f13beae 100644
--- a/src/lsp/LSPClient.js
+++ b/src/lsp/LSPClient.js
@@ -45,10 +45,10 @@ export default class LSPClient {
     };
   }
 
-  async start() {
+  async start(initializationOptions = {}) {
     this._start_process();
 
-    await this._initialize();
+    await this._initialize(initializationOptions);
     await this._didOpen();
 
     this.ready = true;
@@ -65,7 +65,7 @@ export default class LSPClient {
     return once(this, "ready");
   }
 
-  async _initialize() {
+  async _initialize(initializationOptions = {}) {
     const { capabilities, rootUri } = this;
 
     // https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#initialize
@@ -74,6 +74,7 @@ export default class LSPClient {
       clientInfo,
       capabilities,
       rootUri,
+      initializationOptions,
       locale: "en",
     });