> For the complete documentation index, see [llms.txt](https://tdd.shujuwajue.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://tdd.shujuwajue.com/ju-ti-shi-jian/javascript-ce-shi-kuang-jia/chai.md).

# Chai

[官方网站](http://www.chaijs.com/)

CHAI是一个断言库，类似于节点的内置断言。它使测试变得更容易，因为您可以通过代码来运行大量的断言。

* 对数组的单元测试

```javascript
res.body.should.to.be.an.instanceof(Array);
res.body.should.to.have.lengthOf(1);
res.body.should.to.have.deep.nested.property("[0].ean", data.ean);
```