Small changes

src/client.ts

@@ -176,6 +176,13 @@ async function send<T>(
    Public API
 ────────────────────────── */
 
+export async function closeClient() {
+  if (!socket) return;
+  socket.close();
+  socket = null;
+  connecting = null;
+}
+
 export async function addRun(
   useLocalhost: boolean,
   problem: string,

src/extension.ts

@@ -4,6 +4,7 @@ import { startServer, stopServer } from "./server";
 import os from "os";
 import { exec } from "child_process";
 import net from "net";
+import { closeClient } from "./client";
 
 var globalStatusBarItem: vscode.StatusBarItem | undefined;
 
@@ -105,6 +106,7 @@ export function activate(context: vscode.ExtensionContext) {
 
 export function deactivate() {
   stopServer(globalStatusBarItem as any);
+  closeClient();
 }
 
 export function canConnect(

src/move.ts

@@ -129,7 +129,7 @@ export function startMonitoring(useLocalhost: boolean, runId: string) {
           moveId: moveId++,
           changes: {
             from: 0,
-            to: serverText.length,
+            to: serverText?.length || 0,
             insert: editorText,
           },
         },