fix(eio-client): prevent infinite loop with Node.js built-in WebSocket

.github/workflows/ci.yml

@@ -60,3 +60,7 @@ jobs:
       - name: Run tests with fetch instead of XHR (engine.io-client)
         run: npm run test:node-fetch --workspace=engine.io-client
         if: ${{ matrix.node-version == '18' }}
+
+      - name: Run tests with Node.js native WebSocket (engine.io-client)
+        run: npm run test:node-builtin-ws --workspace=engine.io-client
+        if: ${{ matrix.node-version == '22' }}

packages/engine.io-client/lib/transports/websocket.ts

@@ -123,6 +123,7 @@ export abstract class BaseWS extends Transport {
 
   override doClose() {
     if (typeof this.ws !== "undefined") {
+      this.ws.onerror = () => {};
       this.ws.close();
       this.ws = null;
     }

packages/engine.io-client/package.json

@@ -63,6 +63,7 @@
     "test": "npm run format:check && npm run compile && if test \"$BROWSERS\" = \"1\" ; then npm run test:browser; else npm run test:node; fi",
     "test:node": "mocha --bail --require test/support/hooks.js test/index.js test/webtransport.mjs",
     "test:node-fetch": "USE_FETCH=1 npm run test:node",
+    "test:node-builtin-ws": "USE_BUILTIN_WS=1 npm run test:node",
     "test:browser": "zuul test/index.js",
     "build": "rimraf ./dist && rollup -c support/rollup.config.umd.js && rollup -c support/rollup.config.esm.js",
     "bundle-size": "node support/bundle-size.js",

packages/engine.io-client/test/connection.js

@@ -17,6 +17,19 @@ describe("connection", function () {
     });
   });
 
+  it("should connect to localhost (ws)", (done) => {
+    const socket = new Socket({
+      transports: ["websocket"]
+    });
+    socket.on("open", () => {
+      socket.on("message", (data) => {
+        expect(data).to.equal("hi");
+        socket.close();
+        done();
+      });
+    });
+  });
+
   it("should receive multibyte utf-8 strings with polling", (done) => {
     const socket = new Socket();
     socket.on("open", () => {

packages/engine.io-client/test/support/env.js

@@ -35,3 +35,11 @@ if (exports.useFetch) {
   const { transports, Fetch } = require("../..");
   transports.polling = Fetch;
 }
+
+exports.useBuiltinWs = process.env.USE_BUILTIN_WS !== undefined;
+
+if (exports.useBuiltinWs) {
+  console.warn("testing with built-in WebSocket object");
+  const { transports, WebSocket } = require("../..");
+  transports.websocket = WebSocket;
+}

packages/engine.io-client/test/transport.js

@@ -210,7 +210,10 @@ describe("Transport", () => {
   // these are server only
   if (!env.browser) {
     describe("options", () => {
-      it("should accept an `agent` option for WebSockets", (done) => {
+      it("should accept an `agent` option for WebSockets", function (done) {
+        if (env.useBuiltinWs) {
+          return this.skip();
+        }
         const polling = new eio.transports.websocket({
           path: "/engine.io",
           hostname: "localhost",
@@ -269,7 +272,10 @@ describe("Transport", () => {
       });
 
       describe("perMessageDeflate", () => {
-        it("should set threshold", (done) => {
+        it("should set threshold", function (done) {
+          if (env.useBuiltinWs) {
+            return this.skip();
+          }
           const socket = new eio.Socket({
             transports: ["websocket"],
             perMessageDeflate: { threshold: 0 },
@@ -289,7 +295,10 @@ describe("Transport", () => {
           });
         });
 
-        it("should not compress when the byte size is below threshold", (done) => {
+        it("should not compress when the byte size is below threshold", function (done) {
+          if (env.useBuiltinWs) {
+            return this.skip();
+          }
           const socket = new eio.Socket({ transports: ["websocket"] });
           socket.on("open", () => {
             const ws = socket.transport.ws;