backend files

backend/app.test.js

@@ -0,0 +1,35 @@
+const request = require('supertest');
+const app = require('./index');
+
+describe('Backend API', () => {
+  it('should return health check message on /', async () => {
+    const res = await request(app).get('/');
+    expect(res.statusCode).toEqual(200);
+    expect(res.text).toContain('Todo API is running');
+  });
+
+  it('should fetch all todos', async () => {
+    const res = await request(app).get('/api/todos');
+    expect(res.statusCode).toEqual(200);
+    expect(Array.isArray(res.body)).toBeTruthy();
+    expect(res.body.length).toBeGreaterThanOrEqual(2);
+  });
+
+  it('should add a new todo', async () => {
+    const newTodo = { task: 'Test task' };
+    const res = await request(app)
+      .post('/api/todos')
+      .send(newTodo);
+    expect(res.statusCode).toEqual(201);
+    expect(res.body.task).toEqual('Test task');
+    expect(res.body).toHaveProperty('id');
+  });
+
+  it('should fail to add a todo without a task', async () => {
+    const res = await request(app)
+      .post('/api/todos')
+      .send({});
+    expect(res.statusCode).toEqual(400);
+    expect(res.body.error).toEqual('Task is required');
+  });
+});