Use better connection error object in browser

Author: t2t2

src/base.ts

@@ -78,11 +78,18 @@ export abstract class BaseOBSWebSocket extends EventEmitter<MapValueToArgsArray<
 this.emit('Hello', hello);
 return this.identify(hello, password, identificationParams);
 })(),
-connectionClosedPromise.then(e => {
-throw e;
-}),
-connectionErrorPromise.then(e => {
-throw e;
+// Choose the best promise for connection error/close
+// In browser connection close has close code + reason,
+// while in node error event has these
+new Promise<never>((resolve, reject) => {
+void connectionErrorPromise.then(e => {
+if (e.message) {
+reject(e);
+}
+});
+void connectionClosedPromise.then(e => {
+reject(e);
+});
 }),
 ]);
 } catch (error: unknown) {

tests/invalid-server.test.ts

@@ -85,3 +85,32 @@ test('server returns wrong protocol', async t => {
 
 await obs.disconnect();
 });
+
+test('no server listening', async t => {
+const obs = new OBSWebSocket();
+
+// Temporarily create a websocket server to guarantee an unused port
+const port = await new Promise<number>(resolve => {
+const server = new WebSocketServer({
+port: 0,
+handleProtocols() {
+return 'dummy';
+},
+}, () => {
+const {port} = server.address() as AddressInfo;
+server.close(() => {
+resolve(port);
+});
+});
+});
+
+t.false(obs.identified);
+await t.throwsAsync(obs.connect(`ws://127.0.0.1:${port}`), {
+instanceOf: OBSWebSocketError,
+message: `connect ECONNREFUSED 127.0.0.1:${port}`,
+code: -1,
+});
+t.false(obs.identified);
+
+await obs.disconnect();
+});