From df484168b238ef1e7ec993eae915e2ed4c96a479 Mon Sep 17 00:00:00 2001
From: Sysix <3897725+Sysix@users.noreply.github.com>
Date: Fri, 17 Oct 2025 20:18:32 +0000
Subject: [PATCH] perf(language_server): return `Diagnostic` when relinting all
 files (#14737)

When relinting the files, the `PossibleFixContent` is not relevant for the processes.
These are:
- changing language server configuration
- changing oxlint configuration
---
 crates/oxc_language_server/src/backend.rs     | 12 ++---------
 .../src/linter/server_linter.rs               | 20 ++++++++++---------
 crates/oxc_language_server/src/worker.rs      | 13 +++++-------
 3 files changed, 18 insertions(+), 27 deletions(-)

diff --git a/crates/oxc_language_server/src/backend.rs b/crates/oxc_language_server/src/backend.rs
index d911a5020bf1c..13a1c9ad4f155 100644
--- a/crates/oxc_language_server/src/backend.rs
+++ b/crates/oxc_language_server/src/backend.rs
@@ -335,12 +335,7 @@ impl LanguageServer for Backend {
             }
 
             if let Some(diagnostics) = diagnostics {
-                for (uri, reports) in &diagnostics.pin() {
-                    new_diagnostics.push((
-                        uri.clone(),
-                        reports.iter().map(|d| d.diagnostic.clone()).collect(),
-                    ));
-                }
+                new_diagnostics.extend(diagnostics);
             }
 
             if let Some(watchers) = watchers
@@ -412,10 +407,7 @@ impl LanguageServer for Backend {
                 continue;
             };
 
-            for (uri, reports) in &diagnostics.pin() {
-                all_diagnostics
-                    .push((uri.clone(), reports.iter().map(|d| d.diagnostic.clone()).collect()));
-            }
+            all_diagnostics.extend(diagnostics);
         }
 
         if !all_diagnostics.is_empty() {
diff --git a/crates/oxc_language_server/src/linter/server_linter.rs b/crates/oxc_language_server/src/linter/server_linter.rs
index 6bb7e81eae486..92d316b29b78d 100644
--- a/crates/oxc_language_server/src/linter/server_linter.rs
+++ b/crates/oxc_language_server/src/linter/server_linter.rs
@@ -7,7 +7,7 @@ use log::{debug, warn};
 use oxc_linter::{AllowWarnDeny, LintIgnoreMatcher};
 use rustc_hash::{FxBuildHasher, FxHashMap, FxHashSet};
 use tokio::sync::Mutex;
-use tower_lsp_server::lsp_types::Uri;
+use tower_lsp_server::lsp_types::{Diagnostic, Uri};
 
 use oxc_linter::{
     Config, ConfigStore, ConfigStoreBuilder, ExternalPluginStore, LintOptions, Oxlintrc,
@@ -283,17 +283,19 @@ impl ServerLinter {
             .collect()
     }
 
-    pub async fn revalidate_diagnostics(
-        &self,
-        uris: Vec<Uri>,
-    ) -> ConcurrentHashMap<String, Vec<DiagnosticReport>> {
-        let map = ConcurrentHashMap::default();
+    pub async fn revalidate_diagnostics(&self, uris: Vec<Uri>) -> Vec<(String, Vec<Diagnostic>)> {
+        let mut diagnostics = Vec::with_capacity(uris.len());
         for uri in uris {
-            if let Some(diagnostics) = self.run_single(&uri, None, ServerLinterRun::Always).await {
-                map.pin().insert(uri.to_string(), diagnostics);
+            if let Some(file_diagnostic) =
+                self.run_single(&uri, None, ServerLinterRun::Always).await
+            {
+                diagnostics.push((
+                    uri.to_string(),
+                    file_diagnostic.into_iter().map(|d| d.diagnostic).collect(),
+                ));
             }
         }
-        map
+        diagnostics
     }
 
     fn is_ignored(&self, uri: &Uri) -> bool {
diff --git a/crates/oxc_language_server/src/worker.rs b/crates/oxc_language_server/src/worker.rs
index ce4b78a536bf0..4d12e9aaadd34 100644
--- a/crates/oxc_language_server/src/worker.rs
+++ b/crates/oxc_language_server/src/worker.rs
@@ -11,7 +11,7 @@ use tower_lsp_server::{
 };
 
 use crate::{
-    ConcurrentHashMap, FORMAT_CONFIG_FILE,
+    FORMAT_CONFIG_FILE,
     code_actions::{apply_all_fix_code_action, apply_fix_code_actions, fix_all_text_edit},
     formatter::{options::FormatOptions, server_formatter::ServerFormatter},
     linter::{
@@ -215,12 +215,9 @@ impl WorkspaceWorker {
 
     /// Revalidate diagnostics for the given URIs
     /// This will re-lint all opened files and return the new diagnostics
-    async fn revalidate_diagnostics(
-        &self,
-        uris: Vec<Uri>,
-    ) -> ConcurrentHashMap<String, Vec<DiagnosticReport>> {
+    async fn revalidate_diagnostics(&self, uris: Vec<Uri>) -> Vec<(String, Vec<Diagnostic>)> {
         let Some(server_linter) = &*self.server_linter.read().await else {
-            return ConcurrentHashMap::default();
+            return Vec::new();
         };
 
         server_linter.revalidate_diagnostics(uris).await
@@ -319,7 +316,7 @@ impl WorkspaceWorker {
     pub async fn did_change_watched_files(
         &self,
         _file_event: &FileEvent,
-    ) -> Option<ConcurrentHashMap<String, Vec<DiagnosticReport>>> {
+    ) -> Option<Vec<(String, Vec<Diagnostic>)>> {
         // TODO: the tools should implement a helper function to detect if the changed file is relevant
         let files = {
             let server_linter_guard = self.server_linter.read().await;
@@ -348,7 +345,7 @@ impl WorkspaceWorker {
         changed_options: &Options,
     ) -> (
         // Diagnostic reports that need to be revalidated
-        Option<ConcurrentHashMap<String, Vec<DiagnosticReport>>>,
+        Option<Vec<(String, Vec<Diagnostic>)>>,
         // File system watcher for lint/fmt config changes
         // - `None` if no watcher changes are needed
         // - empty vector if all watchers should be removed