✅(frontend) switch to vitest and enhance testability

Migrated from jest to vitest for server/y-provider, gaining faster runs,
esm-native support and cleaner mocking.

Signed-off-by: Stephan Meijer <me@stephanmeijer.com>

src/frontend/servers/y-provider/__tests__/convert.test.ts

@@ -1,66 +1,93 @@
+import { Hocuspocus } from '@hocuspocus/server';
 import request from 'supertest';
+import { describe, expect, test, vi } from 'vitest';
+import { mock } from 'vitest-mock-extended';
 
-const port = 5556;
-const origin = 'http://localhost:3000';
-
-jest.mock('../src/env', () => {
+vi.mock('../src/env', async (importOriginal) => {
   return {
-    PORT: port,
-    COLLABORATION_SERVER_ORIGIN: origin,
+    ...(await importOriginal()),
+    COLLABORATION_SERVER_ORIGIN: 'http://localhost:3000',
     Y_PROVIDER_API_KEY: 'yprovider-api-key',
   };
 });
 
-import { initServer } from '../src/servers/appServer';
+import { initApp } from '@/servers';
 
-console.error = jest.fn();
-const { app, server } = initServer();
+import {
+  Y_PROVIDER_API_KEY as apiKey,
+  COLLABORATION_SERVER_ORIGIN as origin,
+} from '../src/env';
+
+console.error = vi.fn();
+
+const mockOpts = {
+  fallbackMockImplementation: () => {
+    throw new Error('Unexpected call.');
+  },
+};
 
 describe('Server Tests', () => {
-  afterAll(() => {
-    server.close();
-  });
+  test('POST /api/convert with incorrect API key should responds with 403', async () => {
+    const hocuspocus = mock<Hocuspocus>({}, mockOpts);
+    const app = initApp(hocuspocus);
 
-  test('POST /api/convert with incorrect API key should return 403', async () => {
-    const response = await request(app as any)
+    const response = await request(app)
       .post('/api/convert')
       .set('Origin', origin)
       .set('Authorization', 'wrong-api-key');
 
     expect(response.status).toBe(403);
-    expect(response.body.error).toBe('Forbidden: Invalid API Key');
+    expect(response.body).toStrictEqual({
+      error: 'Forbidden: Invalid API Key',
+    });
   });
 
   test('POST /api/convert with a Bearer token', async () => {
-    const response = await request(app as any)
+    const hocuspocus = mock<Hocuspocus>({}, mockOpts);
+    const app = initApp(hocuspocus);
+
+    const response = await request(app)
       .post('/api/convert')
       .set('Origin', origin)
       .set('Authorization', 'Bearer test-secret-api-key');
 
     // Warning: Changing the authorization header to Bearer token format will break backend compatibility with this microservice.
     expect(response.status).toBe(403);
+    expect(response.body).toStrictEqual({
+      error: 'Forbidden: Invalid API Key',
+    });
   });
 
   test('POST /api/convert with missing body param content', async () => {
-    const response = await request(app as any)
+    const hocuspocus = mock<Hocuspocus>({}, mockOpts);
+    const app = initApp(hocuspocus);
+
+    const response = await request(app)
       .post('/api/convert')
       .set('Origin', origin)
-      .set('Authorization', 'yprovider-api-key');
+      .set('Authorization', apiKey);
 
     expect(response.status).toBe(400);
-    expect(response.body.error).toBe('Invalid request: missing content');
+    expect(response.body).toStrictEqual({
+      error: 'Invalid request: missing content',
+    });
   });
 
   test('POST /api/convert with body param content being an empty string', async () => {
-    const response = await request(app as any)
+    const hocuspocus = mock<Hocuspocus>({}, mockOpts);
+    const app = initApp(hocuspocus);
+
+    const response = await request(app)
       .post('/api/convert')
       .set('Origin', origin)
-      .set('Authorization', 'yprovider-api-key')
+      .set('Authorization', apiKey)
       .send({
         content: '',
       });
 
     expect(response.status).toBe(400);
-    expect(response.body.error).toBe('Invalid request: missing content');
+    expect(response.body).toStrictEqual({
+      error: 'Invalid request: missing content',
+    });
   });
 });