diff --git a/crates/language/src/buffer.rs b/crates/language/src/buffer.rs
index b106110c33..6a28d777a0 100644
--- a/crates/language/src/buffer.rs
+++ b/crates/language/src/buffer.rs
@@ -1569,11 +1569,25 @@ impl Buffer {
         self.send_operation(op, true, cx);
     }
 
-    pub fn get_diagnostics(&self, server_id: LanguageServerId) -> Option<&DiagnosticSet> {
-        let Ok(idx) = self.diagnostics.binary_search_by_key(&server_id, |v| v.0) else {
-            return None;
-        };
-        Some(&self.diagnostics[idx].1)
+    /// Retrieve the diagnostics entries for the given language server, or all
+    /// diagnostics if `server_id` is `None`.
+    pub fn get_diagnostics(
+        &self,
+        server_id: Option<LanguageServerId>,
+    ) -> Option<Vec<&DiagnosticEntry<Anchor>>> {
+        if let Some(server_id) = server_id {
+            let Ok(idx) = self.diagnostics.binary_search_by_key(&server_id, |v| v.0) else {
+                return None;
+            };
+            Some(self.diagnostics[idx].1.iter().collect::<Vec<_>>())
+        } else {
+            let diag = self
+                .diagnostics
+                .iter()
+                .flat_map(|(_, diags)| (*diags).iter())
+                .collect::<Vec<_>>();
+            Some(diag)
+        }
     }
 
     fn request_autoindent(&mut self, cx: &mut Context<Self>) {
diff --git a/crates/project/src/lsp_store.rs b/crates/project/src/lsp_store.rs
index d2958dce01..ea96dae5ec 100644
--- a/crates/project/src/lsp_store.rs
+++ b/crates/project/src/lsp_store.rs
@@ -7588,9 +7588,8 @@ impl LspStore {
                 let snapshot = buffer_handle.read(cx).snapshot();
                 let buffer = buffer_handle.read(cx);
                 let reused_diagnostics = buffer
-                    .get_diagnostics(server_id)
-                    .into_iter()
-                    .flat_map(|diag| {
+                    .get_diagnostics(Some(server_id))
+                    .map(|diag| {
                         diag.iter()
                             .filter(|v| merge(buffer, &v.diagnostic, cx))
                             .map(|v| {
@@ -7601,8 +7600,9 @@ impl LspStore {
                                     diagnostic: v.diagnostic.clone(),
                                 }
                             })
+                            .collect::<Vec<_>>()
                     })
-                    .collect::<Vec<_>>();
+                    .unwrap_or_default();
 
                 self.as_local_mut()
                     .context("cannot merge diagnostics on a remote LspStore")?