Suppress another logged backtrace (#44896)

Kirill Bulatov created 1 week ago

Do not log any error when the binary is not found, do not show any
backtrace when logging errors.

<img width="2032" height="1161" alt="bad"
src="https://github.com/user-attachments/assets/3f379c90-e61f-447f-9e46-fed989380164"
/>


Release Notes:

- N/A

Change summary

crates/languages/src/rust.rs | 32 ++++++++++++++++++++++++--------
1 file changed, 24 insertions(+), 8 deletions(-)

Detailed changes

crates/languages/src/rust.rs

@@ -1126,9 +1126,11 @@ fn package_name_from_pkgid(pkgid: &str) -> Option<&str> {
 }
 
 async fn get_cached_server_binary(container_dir: PathBuf) -> Option<LanguageServerBinary> {
-    maybe!(async {
+    let binary_result = maybe!(async {
         let mut last = None;
-        let mut entries = fs::read_dir(&container_dir).await?;
+        let mut entries = fs::read_dir(&container_dir)
+            .await
+            .with_context(|| format!("listing {container_dir:?}"))?;
         while let Some(entry) = entries.next().await {
             let path = entry?.path();
             if path.extension().is_some_and(|ext| ext == "metadata") {
@@ -1137,20 +1139,34 @@ async fn get_cached_server_binary(container_dir: PathBuf) -> Option<LanguageServ
             last = Some(path);
         }
 
-        let path = last.context("no cached binary")?;
+        let path = match last {
+            Some(last) => last,
+            None => return Ok(None),
+        };
         let path = match RustLspAdapter::GITHUB_ASSET_KIND {
             AssetKind::TarGz | AssetKind::Gz => path, // Tar and gzip extract in place.
             AssetKind::Zip => path.join("rust-analyzer.exe"), // zip contains a .exe
         };
 
-        anyhow::Ok(LanguageServerBinary {
+        anyhow::Ok(Some(LanguageServerBinary {
             path,
             env: None,
-            arguments: Default::default(),
-        })
+            arguments: Vec::new(),
+        }))
     })
-    .await
-    .log_err()
+    .await;
+
+    match binary_result {
+        Ok(Some(binary)) => Some(binary),
+        Ok(None) => {
+            log::info!("No cached rust-analyzer binary found");
+            None
+        }
+        Err(e) => {
+            log::error!("Failed to look up cached rust-analyzer binary: {e:#}");
+            None
+        }
+    }
 }
 
 fn test_fragment(variables: &TaskVariables, path: &Path, stem: &str) -> String {