websocket: do not close when protocol supports it

This commit updates the WebSocket handler to not call ws.close()
when stdin is closed but the ws protocol already supports
closing (v5 protocol for example).

Author: cjihrig

src/web-socket-handler.ts

@@ -96,6 +96,7 @@ export class WebSocketHandler implements WebSocketInterface {
                 buff.writeUint8(this.CloseStream, 0);
                 buff.writeUint8(this.StdinStream, 1);
                 ws.send(buff);
+                return;
             }
             ws.close();
         });

src/web-socket-handler_test.ts

@@ -404,8 +404,10 @@ describe('V5 protocol support', () => {
             send: (data) => {
                 sent = data;
             },
-            close: () => {},
-        } as WebSocket;
+            close: () => {
+                throw new Error('should not be called');
+            },
+        } as unknown as WebSocket;
         const stdinStream = new ReadableStreamBuffer();
         WebSocketHandler.handleStandardInput(ws, stdinStream);
         stdinStream.emit('end');