Vue.js单元测试-如何检查组件是否具有方法？

Question

I have a simple component with one method in it. I would like to check if a method in it exists. I know that I can check, if a component contains a certain class or a string, but can't figure out how to check for a method's name. Couldn't find any simple explanation.

Component to test:

<template>
    <div>
      <a id="returnButton" href="#" @click="toMainList" class="d-flex align-items-center back-to-button">
          <font-awesome-icon :icon="['fas', 'arrow-left']" class="fontBasicIcon back-to-button-icon" />
          <div>Back</div>
      </a>
    </div>
</template>

<script>
    import router from '@/router'

    export default {
        name: 'back-to-button',
        data () {
            return {
            }
        },
        methods:{
            toMainList(){
                $router.push('/mainlist');
            }
        }
    }
</script>

Answer 1

Assuming you use Jest and mount your component to test via shallowMount or mount , the wrapper returned gives you access to the Vue instance (including all it's methods)

const wrapper = shallowMount(Foo)
let instance = wrapper.vm // <- the Vue instance
let myMethod = instance.myMethod // <- a method callend 'myMethod' on the Vue instance

if(myMethod != undefined) {
  console.log("method 'myMethod' exists")
}