Version

3.0.2

Reproduction link

https://github.com/alperkay/vue-3-default-unit-test-error

Steps to reproduce

-Make sure you have the latest vue cli which is 4.5.8 as of this writing. -Run vue create example-app -Select "Manually select features" -Select Babel, Typescript, unit testing -Select 3.x preview -Select use class-style component syntax "yes" -use Babel "yes" -pick Jest for unit testing

Once the app is created, cd into the directory and run npm run test:unit.

The sample test fails with the following error:

  console.warn node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:40
    [Vue warn]: Property "msg" was accessed during render but is not defined on instance.
      at <Anonymous msg="new message" ref="VTU_COMPONENT" >
      at <VTUROOT>

What is expected?

The unit test should recognize the prop being passed to the HelloWorld.vue component.

What is actually happening?

It doesn't detect / take into account the prop provided inside the example.spec.ts file. It fails with this error:

 console.warn node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:40
    [Vue warn]: Property "msg" was accessed during render but is not defined on instance.
      at <Anonymous msg="new message" ref="VTU_COMPONENT" >
      at <VTUROOT>

Please open the issue on the relevant repository like vue-class-component if this was already fixed in https://github.com/vuejs/vue-cli/issues/5974

Please open the issue on the relevant repository like vue-class-component if this was already fixed in vuejs/vue-cli#5974

You're totally right. I didn't realise that this was happening due to vue-class-component. I'll open the issue there. Thanks for noticing.