Add test to chat example (#160)

* Add test to chat example

* Add test to chat example

Author: simon-johansson

ts/streaming-chat/README.md

@@ -33,6 +33,12 @@ You can also access Encore's [local developer dashboard](https://encore.dev/docs
 
 In you change the frontend then run `npm run build` to build a new frontend in the `dist` folder.
 
+## Testing
+
+```bash
+encore test
+```
+
 ## Deployment
 
 Deploy your application to a staging environment in Encore's free development cloud:

ts/streaming-chat/chat/chat.test.ts

@@ -0,0 +1,35 @@
+import { describe, expect, test } from "vitest";
+import { chat } from "~encore/clients";
+
+describe("chat", () => {
+  test("should get back own message with correct parameters", async () => {
+    // Connect to the chat server
+    const stream = await chat.chat({ id: "user-id" });
+
+    // Send a message to the server
+    await stream.send({ username: "foo", msg: "hello" });
+
+    // Receive a message from the server
+    const { msg, userID, username } = await stream.recv();
+    expect(userID).toBe("user-id");
+    expect(msg).toBe("hello");
+    expect(username).toBe("foo");
+  });
+
+  test("should get other users message", async () => {
+    // Connect clients to the chat server
+    const stream1 = await chat.chat({ id: "user-1" });
+    const stream2 = await chat.chat({ id: "user-2" });
+    const stream3 = await chat.chat({ id: "user-3" });
+
+    // Send a message from one client
+    await stream1.send({ username: "foo", msg: "hello" });
+
+    // Receive the message from the other clients
+    const stream2Results = await stream2.recv();
+    const stream3Results = await stream3.recv();
+
+    expect(stream2Results.userID).toBe("user-1");
+    expect(stream3Results.userID).toBe("user-1");
+  });
+});