mocha测试中的共享功能

// 引入所需模块和资源
const assert = require('assert');
const { MongoClient } = require('mongodb');

// 设置共享资源
let db;

// 在before钩子中创建数据库连接
before(async () => {
  const client = new MongoClient('mongodb://localhost:27017');
  await client.connect();
  db = client.db('test');
});

// 在after钩子中关闭数据库连接
after(async () => {
  await db.client.close();
});

// 在beforeEach钩子中设置初始状态
beforeEach(async () => {
  await db.collection('users').deleteMany({});
  await db.collection('users').insertOne({ name: 'Alice', age: 25 });
});

// 测试用例
describe('User', () => {
  it('should return the correct user count', async function () {
    const count = await db.collection('users').countDocuments();
    assert.strictEqual(count, 1);
  });

  it('should return the correct user age', async function () {
    const user = await db.collection('users').findOne({ name: 'Alice' });
    assert.strictEqual(user.age, 25);
  });
});