使用Mocha Chai和Sinon测试去抖的Vue方法

Question

If I have a Vue component like:

import lodash from 'lodash';

export default {

  //...data, props etc

  methods: {
    someFunction: lodash.debounce(function debouncedsomeFunction() {
      return 'test';
    }, 200)
  }

};

How would I go about testing someFunction with Mocha + Chai + Sinon?

Answer 1

There are several potential approaches, but it sounds like you want to mock lodash. I'll list the steps linearly for ease of presentation, but you'll probably want to distribute them appropriately within your test blocks and hooks. I'm also assuming the only call to debounce is the method in question. If not, adjust the following accordingly.

import * as Lodash from "lodash";
const debounce = sinon.stub(Lodash, "debounce").returns(() => {});
// create your component
expect(debounce.calledOnce).to.equal(true);
expect(debounce.firstCall.args[0]).to.be.a("function");
expect(debounce.firstCall.args[0]()).to.equal("test");
Lodash.debounce.restore();