Question

我正在编写一个小型测试，以检查是否某些代码确实写入了我的mongo数据库。我收到来自Jest的以下错误消息，该代码确实有效。

Timeout - Async callback was not invoked within the 5000ms timeout specified by jest.setTimeout.Error: Timeout - Async callback was not invoked within the 5000ms timeout specified by jest.setTimeout.

对于我的测试，我只调用函数并期望一个对象属性，该属性指定操作是否成功

const {clearDataBase, loadData} = require('../src/utils/dataloader')

beforeEach(clearDataBase)
test('Should write all data into database', () => {   
    jest.setTimeout(30000);
    const result = loadData() 
    expect(result.status).toBe(201)
})

原始函数解析JSON文件并将某些参数保存到数据库中：

const loadData = () => {
    try{
        request(url, async (err, res, body) => {
            const data = JSON.parse(body)
            // ... Loads a lot of data, removed for this post only!
        })
        return { error: undefined, status: 201 }
    } catch(e){
        return { error: e, status: undefined }
    }
}

Answer 1

您应该使用Promises来确保仅在执行expect()函数之后调用loadData。 Jest Async doc

在下面修改您的代码以使用promises

const {clearDataBase, loadData} = require('../src/utils/dataloader')

beforeEach(clearDataBase)
test('Should write all data into database', () => {   
    jest.setTimeout(30000);
    loadData().then(result => expect(result.status).toBe(201));
})


const loadData = () => new Promise((resolve, reject) => {
  return request(url, async (err, res, body) => {
    if (err) return reject({error: err})
    const data = JSON.parse(body)
    // ... Loads alot of data, removed for this post only!
    return resolve({ error: undefined, status: 201 })
  })
})

5000ms超时内未调用异步回调

1 个答案: