🧪 Add tests for testUrls edge cases and fix fallback

Co-authored-by: sunnylqm <615282+sunnylqm@users.noreply.github.com>

Author: google-labs-jules[bot]

src/utils/http-helper.ts

@@ -57,7 +57,12 @@ export const testUrls = async (urls?: string[]) => {
   if (!urls?.length) {
     return null;
   }
-  const ret = await promiseAny(urls.map(ping));
+  let ret: string | null = null;
+  try {
+    ret = await promiseAny(urls.map(ping));
+  } catch (e) {
+    // fallback to urls[0]
+  }
   if (ret) {
     return ret;
   }

tests/http-helper.test.ts

@@ -1,4 +1,11 @@
-import { describe, expect, test } from 'bun:test';
+
+import { describe, expect, test, beforeEach, afterEach, mock } from 'bun:test';
+
+const runtimeFetchMock = mock(() => Promise.resolve({ status: 200 }));
+mock.module('../src/utils/runtime', () => ({
+  runtimeFetch: runtimeFetchMock,
+}));
+
 import { promiseAny, testUrls } from '../src/utils/http-helper';
 
 describe('promiseAny', () => {
@@ -41,3 +48,45 @@ describe('testUrls', () => {
     expect(result).toBeNull();
   });
 });
+
+describe('testUrls edge cases', () => {
+  afterEach(() => {
+    runtimeFetchMock.mockReset();
+  });
+
+  test('Happy Path: returns successful URL', async () => {
+    runtimeFetchMock.mockImplementation((url: string) => {
+      if (url === 'http://success.local') {
+        return Promise.resolve({ status: 200 });
+      }
+      return Promise.reject(new Error('fail'));
+    });
+
+    const result = await testUrls(['http://fail.local', 'http://success.local']);
+    expect(result).toBe('http://success.local');
+  });
+
+  test('Fastest Response: returns the URL that resolves first', async () => {
+    runtimeFetchMock.mockImplementation((url: string) => {
+      if (url === 'http://fast.local') {
+        return new Promise((resolve) => setTimeout(() => resolve({ status: 200 }), 10));
+      }
+      if (url === 'http://slow.local') {
+        return new Promise((resolve) => setTimeout(() => resolve({ status: 200 }), 50));
+      }
+      return Promise.reject(new Error('fail'));
+    });
+
+    const result = await testUrls(['http://slow.local', 'http://fast.local']);
+    expect(result).toBe('http://fast.local');
+  });
+
+  test('All Failures (Fallback): returns urls[0] without throwing', async () => {
+    runtimeFetchMock.mockImplementation(() => {
+      return Promise.resolve({ status: 500 });
+    });
+
+    const result = await testUrls(['http://fail1.local', 'http://fail2.local']);
+    expect(result).toBe('http://fail1.local');
+  });
+});