From 3f544bf76a25245737d5de016cc0651b2c97fb20 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 9 Jan 2026 16:43:41 +0000
Subject: [PATCH 1/2] Initial plan


From 4039b4fbe5375eacb414797726339890182f3758 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 9 Jan 2026 16:47:30 +0000
Subject: [PATCH 2/2] Fix race condition in notifyVisibilityChange

Add isRunning() check before sending notifications to the language
client to prevent "Client is not running" errors in test environments
where the client may not have fully started yet.

Co-authored-by: cklin <1418580+cklin@users.noreply.github.com>
---
 extensions/ql-vscode/src/language-support/language-client.ts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/extensions/ql-vscode/src/language-support/language-client.ts b/extensions/ql-vscode/src/language-support/language-client.ts
index 07a3296b1af..df060c21944 100644
--- a/extensions/ql-vscode/src/language-support/language-client.ts
+++ b/extensions/ql-vscode/src/language-support/language-client.ts
@@ -45,6 +45,10 @@ export class CodeQLLanguageClient extends LanguageClient {
   }
 
   notifyVisibilityChange(editors: readonly TextEditor[]) {
+    // Only send notification if the language client is running to avoid race conditions
+    if (!this.isRunning()) {
+      return;
+    }
     const files = editors
       .filter((e) => e.document.uri.scheme === "file")
       .map((e) => e.document.uri.toString());