<template>
    <form @submit.prevent="$emit('submitEventTriggered')">
        <button type="submit">Submit Form</button>
    </form>
</template>

<script>
    export default {}
</script>

import {shallowMount} from '@vue/test-utils'
import {assert} from 'chai'
import Form from '@/components/Form.vue'

describe.only('Form', () => {

    it('button click triggers submit event', () => {
        const wrapper = shallowMount(Form)

        wrapper.find('[type='submit']').trigger('click')

        assert.exists(wrapper.emitted('submitEventTriggered'), 'Form submit not triggered')
    })

})

AssertionError: Form submit event triggered: expected undefined to exist