unittesting a plugin, "Cannot set properties of null"

[jamercee]

Having trouble unit testing a specific vuejs plugin, but I think my problem is more of a general lack of understanding unit testing in the vuejs framework. The plugin is the vue3-recaptcha-v2 plugin. I have a component App.vue with the following

<script setup>
import { ref } from "vue"
import { VueRecaptcha } from "vue3-recaptcha-v2"
const recaptchaWidget = ref(null)
</script>

<template>
<vue-recaptcha @widget-id="recaptchaWidget = $event" />
</template>

The little app works as expected, but I can't develop a unit test harness to test my app. My unit test is this:

import { describe, it } from 'vitest'
import { mount, config } from '@vue/test-utils'
import VueRecaptcha from 'vue3-recaptcha-v2'
import App from '../App.vue'

config.plugins.VueWrapper.install(VueRecaptcha, { siteKey: 'fake-key'})

describe('App test', () => {
  it('mount properly', () => {
    mount(App)
  })
})

A run of npm run test:unit

Yields the error:

stderr | src/__tests__/App.test.js > App test > mount properly
[Vue warn]: injection "Symbol(recaptchaSiteKey)" not found.
  at <VueRecaptcha onWidgetId=fn >
  at <App ref="VTU_COMPONENT" >
  at <VTUROOT>

 ❯ src/__tests__/App.test.js (1)
   ❯ App test (1)
     × mount properly

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ Failed Tests 1 ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯

 FAIL  src/__tests__/App.test.js > App test > mount properly
TypeError: Cannot set properties of null (setting 'onload')
 ❯ node_modules/vue3-recaptcha-v2/dist/vue3-recaptcha-v2.js:1:1342

I believe the onload reference is because the VueRecaptcha plugin is attempting to set an onload event-handler on the dom which must not yet be setup correctly? Sorry, I'm lost and have been working on this for several days. If anyone could point me in the right direction, it would be much appreciated.

Versions

"dependencies": {
    "vue": "^3.2.47",
    "vue3-recaptcha-v2": "^1.0.1"
  },
  "devDependencies": {
    "@vitejs/plugin-vue": "^4.0.0",
    "@vue/test-utils": "^2.3.0",
    "jsdom": "^21.1.0",
    "vite": "^4.1.4",
    "vitest": "^0.29.1"
  }

[liulinboyi]

Can you provide a minimum reproduction or a repository? Thanks.