async-await - mocha async/await 测试因超时而失败

Question

我想用 Mocha 测试异步代码.

我跟着这个教程testing-promises-with-mocha .最后，它说最好的方法是 async/await。

以下是我的代码，我打算将 setTimeout 设置为比 Mocha 默认值更长的时间。

describe('features', () => {
  it('assertion success', async() => {
    const resolvingPromise = new Promise( resolve => {
      setTimeout(() => {
        resolve('promise resolved')
      }, 3000)
    })

    const result = await resolvingPromise
    expect(result).to.equal('promise resolved')
  })
})

Mocha 给我的错误如下:

Error: Timeout of 2000ms exceeded. For async tests and hooks, 
ensure "done()" is called; if returning a Promise, ensure it resolves...

如何解决错误？简单套装 mocha --timeout 10000更长？

谢谢你的时间!

Mocha: 5.2.0
Chai: 4.2.0

Answer 1

对于异步测试，您应该调用 done()打回来。

describe('features', () => {
  it('assertion success', async(done) => { // pass done here
    const resolvingPromise = new Promise( resolve => {
      setTimeout(() => {
        resolve('promise resolved')
      }, 3000)
    })

    const result = await resolvingPromise
    expect(result).to.equal('promise resolved')
    done() // invoke at end
  })
})