From 8e4f30abcb83ab5ca920f8d545adbe15aaf4053a Mon Sep 17 00:00:00 2001
From: Lukas Wirth <lukas@zed.dev>
Date: Thu, 14 Aug 2025 10:16:25 +0200
Subject: [PATCH] project: Print error causes when failing to spawn lsp command
 (#36163)

cc https://github.com/zed-industries/zed/issues/34666

Display printing anyhow errors only renders the error itself, but not
any of its causes so we've been dropping the important context when
showing the issue to the users.

Release Notes:

- N/A
---
 crates/lsp/src/lsp.rs           |  4 ++--
 crates/project/src/lsp_store.rs | 14 +++++++++-----
 2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/crates/lsp/src/lsp.rs b/crates/lsp/src/lsp.rs
index 22a227c2310b8c6aa61d8d1509bdd87cfa5a2e8d..ce9e2fe229c0aded6fac31c260e334445f987f03 100644
--- a/crates/lsp/src/lsp.rs
+++ b/crates/lsp/src/lsp.rs
@@ -318,6 +318,8 @@ impl LanguageServer {
         } else {
             root_path.parent().unwrap_or_else(|| Path::new("/"))
         };
+        let root_uri = Url::from_file_path(&working_dir)
+            .map_err(|()| anyhow!("{working_dir:?} is not a valid URI"))?;
 
         log::info!(
             "starting language server process. binary path: {:?}, working directory: {:?}, args: {:?}",
@@ -345,8 +347,6 @@ impl LanguageServer {
         let stdin = server.stdin.take().unwrap();
         let stdout = server.stdout.take().unwrap();
         let stderr = server.stderr.take().unwrap();
-        let root_uri = Url::from_file_path(&working_dir)
-            .map_err(|()| anyhow!("{working_dir:?} is not a valid URI"))?;
         let server = Self::new_internal(
             server_id,
             server_name,
diff --git a/crates/project/src/lsp_store.rs b/crates/project/src/lsp_store.rs
index 827341d60dff0d7882f05664e1fec12b8d1f6d28..60d847023fbcf1d0839dfd53f688a7a11eb156bb 100644
--- a/crates/project/src/lsp_store.rs
+++ b/crates/project/src/lsp_store.rs
@@ -390,13 +390,17 @@ impl LocalLspStore {
                         delegate.update_status(
                             adapter.name(),
                             BinaryStatus::Failed {
-                                error: format!("{err}\n-- stderr--\n{log}"),
+                                error: if log.is_empty() {
+                                    format!("{err:#}")
+                                } else {
+                                    format!("{err:#}\n-- stderr --\n{log}")
+                                },
                             },
                         );
-                        let message =
-                            format!("Failed to start language server {server_name:?}: {err:#?}");
-                        log::error!("{message}");
-                        log::error!("server stderr: {log}");
+                        log::error!("Failed to start language server {server_name:?}: {err:?}");
+                        if !log.is_empty() {
+                            log::error!("server stderr: {log}");
+                        }
                         None
                     }
                 }